Code of Federal Regulations, 2010 CFR
2010-10-01
... chapter for exceptions on bolting used in fluid power and control systems. (b) Carbon steel bolts or bolt... less than that at the root of the threads. They must have heavy semifinished hexagonal nuts in...
NASA Technical Reports Server (NTRS)
Bishop, R.
1983-01-01
Threaded fastener locks parts securely together despite together large loosening torques, even under conditions of high temperature and vibration. Positive locking action is suitable for use where conventional fasteners tend to work loose--for example, on high-speed rotating machinery. Bolt, nut and key are joined together so key occupies alined slots in bolt and nut and prevents nut from rotating off bolt.
A One-Hand Nut and Bolt Assembly Tool
NASA Technical Reports Server (NTRS)
Spencer, J. M.
1984-01-01
Special wrench speeds nut and bolt assembly when insufficient room to hold nut behind bolthole with standard tool. C-clamp shaped box-andsocket-wrench assembly holds nut on blind side in alinement to receive bolt from open side.
Suitable pitch difference to realize anti-loosening performance for various bolts-nuts diameter
NASA Astrophysics Data System (ADS)
Kubo, S.; Tateishi, K.; Noda, N.-A.; Sano, Y.; Takase, Y.; Honda, K.
2018-06-01
In bolt-nut connection, the anti-loosening performance and high fatigue strength are always required with low cost to ensure the connected structure’s safety. In the previous study, a suitable pitch difference between the bolt-nut was obtained as α = 33 μm for M16 JIS bolt- nut through loosening experiment and FEM simulation for tightening process. However, other bolt-nut diameters have not been considered yet. In this paper, therefore, suitable pitch difference is considered for various diameters to realize anti-loosening performance. Since bolt-nut thread geometries are different depending on the diameter, they are expressed as approximate formula. Then, loosening force and anti-loosening force are considered by varying the diameter. Finally, suitable pitch difference {α }minsuit< α < {α }maxsuit was determined from mechanical condition.
More Nuts and Bolts of Michaelis-Menten Enzyme Kinetics
ERIC Educational Resources Information Center
Lechner, Joseph H.
2011-01-01
Several additions to a classroom activity are proposed in which an "enzyme" (the student) converts "substrates" (nut-bolt assemblies) into "products" (separated nuts and bolts) by unscrewing them. (Contains 1 table.)
International Space Station Powered Bolt Nut Anomaly and Failure Analysis Summary
NASA Technical Reports Server (NTRS)
Sievers, Daniel E.; Warden, Harry K.
2010-01-01
A key mechanism used in the on-orbit assembly of the International Space Station (ISS) pressurized elements is the Common Berthing Mechanism. The mechanism that effects the structural connection of the Common Berthing Mechanism halves is the Powered Bolt Assembly. There are sixteen Powered Bolt Assemblies per Common Berthing Mechanism. The Common Berthing Mechanism has a bolt which engages a self aligning Powered Bolt Nut (PBN) on the mating interface (Figure 1). The Powered Bolt Assemblies are preloaded to approximately 84.5 kN (19000 lb) prior to pressurization of the CBM. The PBNs mentioned below, manufactured in 2009, will be used on ISS future missions. An on orbit functional failure of this hardware would be unacceptable and in some instances catastrophic due to the failure of modules to mate and seal the atmosphere, risking loss of crew and ISS functions. The manufacturing processes that create the PBNs need to be strictly controlled. Functional (torque vs. tension) acceptance test failures will be the result of processes not being strictly followed. Without the proper knowledge of thread tolerances, fabrication techniques, and dry film lubricant application processes, PBNs will be, and have been manufactured improperly. The knowledge gained from acceptance test failures and the resolution of those failures, thread fabrication techniques and thread dry film lubrication processes can be applied to many aerospace mechanisms to enhance their performance. Test data and manufactured PBN thread geometry will be discussed for both failed and successfully accepted PBNs.
International Space Station Powered Bolt Nut Anomaly and Failure Analysis Summary
NASA Technical Reports Server (NTRS)
Sievers, Daniel E.; Warden, Harry K.
2010-01-01
A key mechanism used in the on-orbit assembly of the International Space Station (ISS) pressurized elements is the Common Berthing Mechanism (CBM). The mechanism that effects the structural connection of the CBM halves is the Powered Bolt Assembly. There are sixteen Powered Bolt Assemblies per CBM. The CBM has a bolt which engages a self aligning Powered Bolt Nut (PBN) on the mating interface; see Figure 1. The Powered Bolt Assemblies are preloaded to approximately 19 kilo pounds (KIPs) prior to pressurization of the CBM. The PBNs mentioned below, manufactured in 2009, will be used on ISS future missions. An on orbit functional failure of this hardware would be unacceptable and in some instances catastrophic due to the failure of modules to mate and seal the atmosphere, risking loss of crew and ISS functions. The manufacturing processes which create the PBNs need to be strictly controlled. Functional (torque vs. tension) acceptance test failures will be the result of processes not being strictly followed. Without the proper knowledge of thread tolerances, fabrication techniques, and dry film lubricant application processes, PBNs will be, and have been manufactured improperly. The knowledge gained from acceptance test failures and the resolution of those failures, thread fabrication techniques and thread dry film lubrication processes can be applied to many aerospace mechanisms to enhance their performance. Test data and manufactured PBN thread geometry will be discussed for both failed and successfully accepted PBNs.
Matching nuts and bolts in O(n log n) time
DOE Office of Scientific and Technical Information (OSTI.GOV)
Komlos, J.; Ma, Yuan; Szemeredi, E.
Given a set of n nuts of distinct widths and a set of n bolts such that each nut corresponds to a unique bolt of the same width, how should we match every nut with its corresponding bolt by comparing nuts with bolts (no comparison is allowed between two nuts or between two bolts)? The problem can be naturally viewed as a variant of the classic sorting problem as follows. Given two lists of n numbers each such that one list is a permutation of the other, how should we sort the lists by comparisons only between numbers in differentmore » lists? We give an O(n log n)-time deterministic algorithm for the problem. This is optimal up to a constant factor and answers an open question posed by Alon, Blum, Fiat, Kannan, Naor, and Ostrovsky. Moreover, when copies of nuts and bolts are allowed, our algorithm runs in optimal O(log n) time on n processors in Valiant`s parallel comparison tree model. Our algorithm is based on the AKS sorting algorithm with substantial modifications.« less
Fixtures Hold Nuts During Tightening Of Bolts
NASA Technical Reports Server (NTRS)
Gyekenyesi, John Z.
1993-01-01
Two fixtures designed for use on cross-head of tensile testing machine simplify adjustments of crosshead to accommodate specimens of various lengths. Two cagelike fixtures hold pairs of nuts, preventing nuts from turning while bolts are tightened. Enable one person acting alone to tighten bolts.
Bolt installation tool for tightening large nuts and bolts
NASA Technical Reports Server (NTRS)
Mcdougal, A. R.; Norman, R. M.
1974-01-01
Large bolts and nuts are accurately tightened to structures without damaging torque stresses. There are two models of bolt installation tool. One is rigidly mounted and one is hand held. Each model includes torque-multiplier unit.
Automatic, computerized testing of bolts
NASA Technical Reports Server (NTRS)
Carlucci, J., Jr.; Lobb, V. B.; Stoller, F. W.
1970-01-01
System for testing bolts with various platings, lubricants, nuts, and tightening procedures tests 200 fasteners, and processes and summarizes the results, within one month. System measures input torque, nut rotation, bolt clamping force, bolt shank twist, and bolt elongation, data is printed in report form. Test apparatus is described.
Code of Federal Regulations, 2011 CFR
2011-10-01
..., Blanks, Flange Facings, Gaskets, and Bolting § 56.25-20 Bolting. (a) General. (1) Bolts, studs, nuts, and....01-2). (2) Bolts and studs must extend completely through the nuts. (3) See § 58.30-15(c) of this... steel stud bolts must be threaded full length or, if desired, may have reduced shanks of a diameter not...
The Nuts and Bolts of Michaelis-Menten Enzyme Kinetics: Suggestions and Clarifications
ERIC Educational Resources Information Center
Silverstein, Todd
2011-01-01
Matthew Junker's recent article describes a useful and effective enzyme kinetics application and analogy in which students simulate enzyme activity by unscrewing nut-bolt "substrate molecules", thus, converting them into separate nuts and bolts "products". A number of suggestions and corrections are presented that improve the clarity and accuracy…
3D finite element analysis of tightening process of bolt and nut connections with pitch difference
NASA Astrophysics Data System (ADS)
Liu, X.; Noda, N.-A.; Sano, Y.; Huang, Y. T.; Takase, Y.
2018-06-01
In a wide industrial field, the bolt-nut joint is unitized as an important machine element and anti-loosening performance is always required. In this paper, the effect of a slight pitch difference between a bolt and nut is studied. Firstly, by varying the pitch difference, the prevailing torque required for the nut rotation, before the nut touches the clamped body, is measured experimentally. Secondly, the tightening torque is determined as a function of the axial force of the bolt after the nut touches the clamped body. The results show that a large value of pitch difference may provide large prevailing torque that causes an anti-loosening effect although a very large pitch difference may deteriorate the bolt axial force under a certain tightening torque. Thirdly, a suitable pitch difference is determined taking into account the anti-loosening and clamping abilities. Furthermore, the chamfered corners at nut ends are considered, and it is found that the 3D finite element analysis with considering the chamfered nut threads has a good agreement with the experimental observation. Finally, the most desirable pitch difference required for improving anti-loosening is proposed.
Metal-to-ceramic attachment device
Pavelka, Edwin A.; Grindstaff, Quirinus G.; Scheppele, Stuart E.
1985-01-01
A metal-to-ceramic fastening device is disclosed for securing a metal member to a ceramic member with respective confronting surfaces thereon clamped together, comprising a threaded bolt adapted to extend through a bolt hole in the metal member and into an aligned opening in the ceramic member, a rod nut threadedly receiving the bolt and adapted to span the opening in the ceramic member, and a pressure limiting member received on the bolt between the nut and the confronting surface of the metal member for limiting the movement of the nut toward the metal member when the bolt is tightened, so as to limit the pressure applied by the nut to the ceramic member to avoid damage thereto. The fastening device also prevents damage to the ceramic member due to thermal stresses. The pressure limiting member may have a shallow dish-shaped depression facing the rod nut to assist in accommodating thermal stresses.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-01-11
... installed, one-time torquing of the nut and bolt, and corrective actions if necessary. This proposed AD... nut and bolt, and corrective actions if necessary. That AD resulted from reports of parts coming off... of the slat track hardware (i.e., the bolt, washers, downstops, stop location, and nut shown in...
Single wrench separates nuts from free-floating bolts
NASA Technical Reports Server (NTRS)
Thompson, C.
1967-01-01
Pneumatic impact wrench removes the nuts from freely turning bolts when the heads cannot be reached or the shafts anchored. It uses a fixed screwdriver blade that fits a slot cut into the threaded end of the bolt shaft.
Pneumatic wrench retains or discharges nuts or bolts as desired
NASA Technical Reports Server (NTRS)
Bouille, J. R.
1966-01-01
Pneumatic wrench grips, screws or unscrews, and discharges a nut or bolt as desired. The device consists of a standard pneumatic wrench modified with a special hex bolt head socket assembly and a diaphragm air cylinder.
Fatigue testing of metric bolts fitted with lip-type nuts
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dragoni, E.
This paper addresses the effect of the external shape of lip-type nuts on the fatigue strength of commercial M10 bolts loaded in tension. Evolving from the standard configuration, six nut geometries are compared, characterized by lips of different shape (cylindrical, tapered or both) and length. Testing and statistical treatment of the data are performed in accordance with a JSME standard involving 14 specimens for each geometry. Within the class of merely cylindrical lips, only limited advantages over the standard assembly are detected. In particular, the bolt strength remains mostly unaffected by lengthening of the lip beyond one third of themore » nut height. Conversely, tapering of the lip end so as to thin its wall around the entry section of the bolt results in substantial improvements. In this case, the strength increase is roughly proportional to the taper length. Adoption of a tapered lip covering two thirds of the nut height enhances the bolt strength by about one fourth with respect to the standard geometry.« less
Behaviour of steel-concrete composite beams using bolts as shear connectors
NASA Astrophysics Data System (ADS)
Tran, Minh-Tung; Nguyen Van Do, Vuong; Nguyen, Tuan-Anh
2018-04-01
The paper presents an experimental program on the application of bolts as shear connectors for steel-composite beams. Four steel- concrete composite beams and a reference steel beam were made and tested. The aim of the testing program is to examine which forms of the steel bolts can be used effectively for steel-composite beams. The four types of the bolts include: Type 1 the bolt with the nut at the end; Type 2 the bolt bending at 900 hook; Type 3 the bolt without the nut at the end and Type 4 the bolt with the nut at the end but connected with the steel beam by hand welding in other to be connected with the steel beam by bolt connection as in the first three types. The test results showed that beside the traditional shear connectors like shear studs, angle type, channel type, bolts can be used effectively as the shear connectors in steel-composite beams and the application of bolts in Types 1 and 2 in the composite beams gave the better performance for the tested beam.
NASA Technical Reports Server (NTRS)
Oconnor, J. W.; Orem, V. C. (Inventor)
1973-01-01
A description is given of a fastener stretcher used to apply a substantial pure axial tensile force to a structural bolt or similar fastening element. The system is comprised of a pair of telescoping elements, one of which is temporarily secured to the bolt. By spreading the telescoping elements axially, the bolt is tensioned axially to permit a nut or the like to be threaded with a minimum of torque; when the elements are then removed from the bolt, the axial forces on the bolt are taken up by the nut to retain the bolt in its stressed state.
NASA Technical Reports Server (NTRS)
Kerley, James J. (Inventor); Burkhardt, Raymond (Inventor); White, Steven (Inventor)
1994-01-01
A device for testing fasteners such as nuts and bolts is described which consists of a fixed base plate having a number of threaded and unthreaded holes of varying size for receiving the fasteners to be tested, a torque marking paper taped on top the fixed base plate for marking torque-angle indicia, a torque wrench for applying torque to the fasteners being tested, and an indicator for showing the torque applied to the fastener. These elements provide a low cost, nondestructive device for verifying the strength of bolts and nuts.
75 FR 17887 - Airworthiness Directives; The Boeing Company Model 767 Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2010-04-08
... torque to the nut and bolt of the main track downstop assembly. The corrective actions include: Installing a bolt and spacer with a new nut (including applying torque to make sure that it has been.... Tightening the existing nut. Boeing Special Attention Service Bulletin 767-57-0118, dated October 8, 2009...
3-Dimensional Analysis of Deformation of Disk Wheels and Transverse Force of Wheel Bolts
NASA Astrophysics Data System (ADS)
Kagiwada, Tadao; Harada, Hiroyuki
Loosening of the wheel nuts, which fix the disk wheels of automobiles to the wheel hub, may be the cause of accidents where the wheel falls off while the automobile is running. When the transverse force of wheel bolts exceeds a certain proportion of the bolt shaft force, the wheel nut begins to loosen. Further, the force on the bolt shaft may also be influenced by the loads acting to the wheel through the moment caused by the offset of the wheel. This study determined the 3-dimensional deformation of the disk wheels and the transverse forces on the wheel bolt by 3-dimensional numerical analysis. The results established that the transverse force was influenced by the bolt shaft force caused by the bolt fastening and was superposed on that due to the load, and that it fluctuated greatly during the revolution of the wheel. This phenomenon may be a large factor in the loosening of wheel nuts.
An ultrasonic technique for measuring stress in fasteners
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stevens, K. J.; Day, P.; Byron, D.
1999-12-02
High temperature bolting alloys are extensively used in the thermal power generation industry as for example, reheat ESV and Governor valve studs. Remnant life assessment methodologies and plant maintenance procedures require the monitoring of the operational stress levels in these fasteners. Some conventional ultrasonic techniques require longitudinal wave measurements to be undertaken when the nut on the bolt is loosened and then re-tightened. Other techniques use a combination of shear waves and longitudinal waves. In this paper, the problems and pitfalls associated with various ultrasonic techniques for measuring stress in bolts, is discussed. An ultrasonic technique developed for measuring themore » stress in Durehete 1055 bolts is presented. Material from a textured rolled bar has been used as a test bed in the development work. The technique uses shear wave birefringence and compression waves at several frequencies to measure texture, fastener length and the average stress. The technique was developed by making ultrasonic measurements on bolts tensioned in universal testing machines and a hydraulic nut. The ultrasonic measurements of residual stress have been checked against strain gauge measurements. The Durehete bolts have a hollow cylinder geometry of restricted dimensions, which significantly alters compression and shear wave velocities from bulk values and introduces hoop stresses which can be measured by rotating the polarization of the shear wave probe. Modelling of the experimental results has been undertaken using theories for the elastic wave propagation through waveguides. The dispersion equations allow the velocity and length of the fastener to be measured ultrasonically in some situations where the length of the fastener can not be measured directly with a vernier caliper or micrometer and/or where it is undesirable to loosen nuts to take calibration readings of the shear and compression wave velocities.« less
Experimental study on the effect of shape of bolt and nut on fatigue strength for bolted joint
NASA Astrophysics Data System (ADS)
Matsunari, T.; Oda, K.; Tsutsumi, N.; Yakushiji, T.; Noda, N. A.; Sano, Y.
2018-06-01
In this study, the effect of curvature radius of the thread bottom and the pitch difference between of M16 bolt and nut on fatigue strength for bolted joint is considered experimentally. The M16 bolt-nut specimens having the two kinds of thread bottom radii and the pitch differences are prepared. The S-N curves for bolted specimens with different thread shapes are obtained by the stress-controlled fatigue test (stress ratio R>0). The experimental results are compared and discussed in terms of stress analysis. The finite element method is used to make a simulation of the fatigue experiment and the mean stress and stress amplitude at each thread bottom of bolt are analysed. It is found that the initiation and propagation of crack are changed by introducing the pitch difference of α=15 μm from the crack observation in cross section of the bolt specimens after the experiment. Furthermore, the fatigue life can be extended by increasing curvature radius of thread bottom and introducing the pitch difference.
Experiments in Aligning Threaded Parts Using a Robot Hand
NASA Technical Reports Server (NTRS)
Diftler, M. A.; Walker, I. D.
1999-01-01
Techniques for determining and correcting threaded part alignment using force and angular position data are developed to augment currently limited techniques for align- ing threaded parts. These new techniques are based on backspinning a nut with respect to a bolt and measuring the force change that occurs when the bolt "falls" into the nut. Kinematic models that describe the relationship between threaded parts during backspinning are introduced and are used to show how angular alignment may be determined. The models indicate how to distinguish between the aligned and misaligned cases of a bolt and a nut connection by using axial force data only. In addition, by tracking the in-plane relative attitude of the bolt during spinning, data can be obtained on the direction of the angular misalignment which, in turn, is used to correct the misalignment. Results from experiments using a bolt held in a specialized fixture and a three fingers Stanford/JPL hand are presented.
Steel shear strength of anchors with stand-off base plates.
DOT National Transportation Integrated Search
2013-09-01
Sign and signal structures are often connected to concrete foundations through a stand-off annular base plate with a double-nut anchor bolt connection, which leaves exposed anchor bolt lengths below leveling nuts used in these connections. Cantilever...
NASA Technical Reports Server (NTRS)
1978-01-01
In photo, an engineer is using a new Ultrasonic Bolt Stress Monitor developed by NASA's Langley Research Center to determine whether a bolt is properly tightened. A highly accurate device, the monitor is an important tool in construction of such structures as pressure vessels, bridges and power plants, wherein precise measurement of the stress on a tightened bolt is critical. Overtightened or undertightened bolts can fail and cause serious industrial accidents or costly equipment break-downs. There are a number of methods for measuring bolt stress. Most widely used and least costly is the torque wrench, which is inherently inaccurate; it does not take into account the friction between nut and bolt, which has an influence on stress. At the other end of the spectrum, there are accurate stress-measuring systems, but they are expensive and not portable. The battery-powered Langley monitor fills a need; it is inexpensive, lightweight, portable and extremely accurate because it is not subject to friction error. Sound waves are transmitted to the bolt and a return signal is received. As the bolt is tightened, it undergoes changes in resonance due to stress, in the manner that a violin string changes tone when it is tightened. The monitor measures the changes in resonance and provides a reading of real stress on the bolt. The device, patented by NASA, has aroused wide interest and a number of firms have applied for licenses to produce it for the commercial market.
High Powered Rocketry: Design, Construction, and Launching Experience and Analysis
ERIC Educational Resources Information Center
Paulson, Pryce; Curtis, Jarret; Bartel, Evan; Cyr, Waycen Owens; Lamsal, Chiranjivi
2018-01-01
In this study, the nuts and bolts of designing and building a high powered rocket have been presented. A computer simulation program called RockSim was used to design the rocket. Simulation results are consistent with time variations of altitude, velocity, and acceleration obtained in the actual flight. The actual drag coefficient was determined…
NASA Technical Reports Server (NTRS)
Wood, C. M.
1984-01-01
The object of this investigation was to evaluate Vespel for potential application on the Solid Rocket Booster to replace all-metal deformed self-locking nuts and anchor nuts and be used as self-locking elements for bolts and screws. The Vespel self-locking elements were tested for prevailing torque retention at room temperature, after heating to 450 F and exposure for 3 hr, breakaway torque at 450 F and for vibration at a level consistent with the maximum expected on the SRB at lift-off and reentry. The investigation revealed Vespel has properties that can provide a self-locking capability for threaded fasteners up to 450 F and it can be used in nuts and anchor nuts for installation on the SRB. Vespel elements in bolts did not meet all our SRB requirements for reuse, however, we have defined a design for Vespel elements in nuts/anchor nuts that fully meets all requirements. It is recommended that No. 1, 1/4 in. and 5/16 in. nuts/anchor nuts be procured for use on the SRB. This system will eliminate the galling problems now encountered and achieve a much higher reuse life than the present deformed nut design.
Lubricating Holes for Corroded Nuts and Bolts
NASA Technical Reports Server (NTRS)
Penn, B. G.; Clemons, J. M.; Ledbetter, Frank E., III
1986-01-01
Corroded fasteners taken apart more easily. Lubricating holes bored to thread from three of flats. Holes facilitate application of penetrating oil to help loosen nut when rusted onto bolt. Holes make it possible to apply lubricants and rust removers directly to more of thread than otherwise reachable.
Quick-Connect, Slow-Disconnect Bolt
NASA Technical Reports Server (NTRS)
Weddendorf, Bruce
1995-01-01
Proposed bolt functions similarly to device described in article "Quick-Connect, Slow-Disconnect Nut" (MFS-28833). Bolt installed in standard threaded hole simply by pushing it into hole. Once inserted, bolt withdrawn only by turning it in conventional way.
NASA Technical Reports Server (NTRS)
2000-01-01
A licensing agreement between Marshall Space Flight Center and M&A Screw and Machineworks has brought the quick connect nut to the commerical market. Originally designed as part of a project seeking in-space assembly techniques, the quick connect nut is secured around a bolt merely by pushing it onto the bolt and giving it a single twist. Applications for the nuts include oil drilling platforms, mining industry, and other practices that rely on speedy assembly for success.
NASA Technical Reports Server (NTRS)
Crispell, C.
1978-01-01
Data for specific joint design, utilizing various combinations of bolt, nut and lubricants in typical structure of the shuttle booster rocket is obtained. Requirements of the structure performance criteria were to withstand temperatures of 260 C (500 F) and to provide a nut lubricant which would be compatible with sealants used in the joint. Cadmium plating and dry film lubricant meeting the requirements of MIL-L-8937 were the lubricants specified. In a follow up effort, cadmium plating and cetyl alcohol were further specified The materials for the bolt and nut combinations were MP35N and A-286. These materials demand a lubricant to be used to prevent galling of the thread when tightened and also to help reduce the scatter of clamping load in application.
DRAFT one year extension of the short-term national product waiver for stainless steel nuts and bolts used in pipe couplings, restraints, joints, flanges and saddles for State Revolving Fund projects.
Turning caring into business: the nuts and bolts of starting a private-duty home care business.
Smith, Cheryl
2007-10-01
As baby boomers age and home care grows in popularity as an alternative to institutionalized care, opportunities abound for entrepreneurs to meet the demand through professional private-duty businesses. This article examines the nuts and bolts of launching and operating a successful private-duty agency.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-15
... link, bores, bolts, and nuts for corrosion. Corrective actions include installing wing-to-fuselage... lists required parts costs that are covered under warranty, we have assumed that there will be no charge... geometry measurements, and inspecting the wing link, bores, bolts, and nuts for corrosion. Corrective...
NUTS and BOLTS: Applications of Fluorescence Detected Sedimentation
Kroe, Rachel R.; Laue, Thomas M.
2008-01-01
Analytical ultracentrifugation is a widely used method for characterizing the solution behavior of macromolecules. However, the two commonly used detectors (absorbance and interference) impose some fundamental restrictions on the concentrations and complexity of the solutions that can be analyzed. The recent addition of a fluorescence detector for the XL-I analytical ultracentrifuge (AU-FDS) enables two different types of sedimentation experiments. First, the AU-FDS can detect picomolar concentrations of labeled solutes allowing the characterization of very dilute solutions of macromolecules, applications we call Normal Use Tracer Sedimentation (NUTS). The great sensitivity of NUTS analysis allows the characterization of small quantities of materials and high affinity interactions. Second, AU-FDS allows characterization of trace quantities of labeled molecules in solutions containing high concentrations and complex mixtures of unlabeled molecules, applications we call Biological On Line Tracer Sedimentation (BOLTS). The discrimination of BOLTS enables the size distribution of a labeled macromolecule to be determined in biological milieu such as cell lysates and serum. Examples are presented that embody features of both NUTS and BOLTS applications, along with our observations on these applications. PMID:19103145
Self-locking washer and method of use
Vodila, James M.; Huyett, John D.
1991-01-01
A self-locking washer made of a flat elongated piece of material having a slot in one end of it. The washer is designed so that it can be placed underneath bolts or nuts which are already installed without completely removing the bolt or nut. A method of use of the self-locking washer is also disclosed.
A Hands-On Classroom Simulation to Demonstrate Concepts in Enzyme Kinetics
ERIC Educational Resources Information Center
Junker, Matthew
2010-01-01
A classroom exercise is described to introduce enzyme kinetics in an undergraduate biochemistry or chemistry course. The exercise is a simulation in which a student acts as an enzyme that "catalyzes" the unscrewing of a nut from a bolt. With other students assisting, the student enzyme carries out reactions with bolt-nut substrates under different…
NASA Technical Reports Server (NTRS)
Cortes, R. G.
1986-01-01
Less space needed for installation and removal. Nut for use with short bolts torqued with allen wrench. In contrast with standard hexagonal nuts, new nut requires no external wrench clearance on installation surface. Nut has many uses in assemblies where space is limited, especially in automotive and aircraft industries.
ERIC Educational Resources Information Center
Swain, Amy
2013-01-01
Schools of education have seen many changes over the last 100 years (Labaree 2004). More recent modifications have included the slow and steady elimination of the social foundations of education in lieu of a more direct attention to teacher skills and basic training. The increased focus on the so-called "nuts and bolts" of teacher…
Development of Anti-Loosening Performance of Hyper Lock Nut
NASA Astrophysics Data System (ADS)
Nishiyama, Shuji; Migita, Hiroaki; Kataoka, Mitumasa; Nakasaki, Nobuyuki; Murano, Kohshi
Bolted joints are widely used in mechanical structures as they allow easy disassembly for maintenance without high cost. However, vibration-induced loosening due to dynamic loading remains a long-unresolved issue. We have developed a new type of nut named the hyper lock nut (HLN) that offers anti-loosening performance without a complicated tightening process and tools. In this study, we investigated the mechanisms of joints bolted with the HLN, and tightening behavior was analyzed using the three-dimensional finite element method. The analytical results were compared with the experimental results for the HLN, and close qualitative agreement was observed between the two with respect to displacement, tightening force and tightening torque. We found a number of new aspects and plus points for joints bolted with the HLN in comparison to those fastened with JIS standard nuts. It was found that the tightening torque of the HLN is higher than that of JIS standard nuts, and that satisfactory anti-loosening performance can be realized through the thread contact force at the slit region and the angular face of the bearing surface.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Khodam-Mohammadi, A.; Monshizadeh, M.
We give a review of the existence of Taub-NUT/bolt solutions in Einstein Gauss-Bonnet gravity with the parameter {alpha} in six dimensions. Although the spacetime with base space S{sup 2}xS{sup 2} has a curvature singularity at r=N, which does not admit NUT solutions, we may proceed with the same computations as in the CP{sup 2} case. The investigation of thermodynamics of NUT/bolt solutions in six dimensions is carried out. We compute the finite action, mass, entropy, and temperature of the black hole. Then the validity of the first law of thermodynamics is demonstrated. It is shown that in NUT solutions allmore » thermodynamic quantities for both base spaces are related to each other by substituting {alpha}{sup CP{sup k}}=[(k+1)/k]{alpha}{sup S{sup 2}}{sup xS{sup 2}}{sup x...S{sub k}{sup 2}}. So, no further information is given by investigating NUT solutions in the S{sup 2}xS{sup 2} case. This relation is not true for bolt solutions. A generalization of the thermodynamics of black holes to arbitrary even dimensions is made using a new method based on the Gibbs-Duhem relation and Gibbs free energy for NUT solutions. According to this method, the finite action in Einstein Gauss-Bonnet is obtained by considering the generalized finite action in Einstein gravity with an additional term as a function of {alpha}. Stability analysis is done by investigating the heat capacity and entropy in the allowed range of {alpha}, {lambda}, and N. For NUT solutions in d dimensions, there exists a stable phase at a narrow range of {alpha}. In six-dimensional bolt solutions, the metric is completely stable for B=S{sup 2}xS{sup 2} and is completely unstable for the B=CP{sup 2} case.« less
Lowery, Guy B.
1991-01-01
A collar nut comprises a hollow cylinder having fine interior threads at one end for threadably engaging a pump mechanical seal assembly and an inwardly depending flange at the other end. The flange has an enlarged portion with a groove for receiving an O-ring for sealing against the intrusion of pumpage from the exterior. The enlarged portion engages a thrust ring about the pump shaft for crushing a hard O-ring, such as a graphite O-ring. The hard O-ring seals the interior of the mechanical seal assembly and pump housing against the loss of lubricants or leakage of pumpage. The fine threads of the hollow cylinder provide the mechanical advantage for crushing the hard O-ring evenly and easily with a hand tool from the side of the collar nut rather than by tightening a plurality of bolts from the end and streamlines the exterior surface of the mechanical seal. The collar nut avoids the spatial requirements of bolt heads at the end of a seal and associated bolt head turbulence.
Long, Kimberly; Wodarski, John S
2010-05-01
Over the past three decades, existing literature has demanded, and continues to demand, accountability in the delivery of social services through empirically based research and implementation of established norms: this is, and of itself, the true basis of social work. It is through these norms and empirically established models and theories of treatment that a social worker can really do what he/she wants to do: help the client. This article will describe the nuts and bolts of social work; i.e. those theories, models, and the established norms of practice. It is the desire of the author's that all social workers be educated in the nuts and bolts (basics) and that education will be based on empirical evidence that supports behavioral change through intervention and modification.
Cable clamp bolt fixture facilitates assembly in close quarters
NASA Technical Reports Server (NTRS)
Sunderland, G. H.
1967-01-01
Cable clamp bolt holding fixture facilitates forming of electrical cable runs in limited equipment space. The fixture engages the threads of the short clamp bolt through the clamp and maintains tension against clamp tendency to open while the operator installs the nut without difficulty.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dehghani, M.H.; Department of Physics, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, N2L 3G1; Perimeter Institute for Theoretical Physics, 35 Caroline Street North, Waterloo, Ontario
We investigate the existence of Taub-NUT (Newman-Unti-Tamburino) and Taub-bolt solutions in Gauss-Bonnet gravity and obtain the general form of these solutions in d dimensions. We find that for all nonextremal NUT solutions of Einstein gravity having no curvature singularity at r=N, there exist NUT solutions in Gauss-Bonnet gravity that contain these solutions in the limit that the Gauss-Bonnet parameter {alpha} goes to zero. Furthermore there are no NUT solutions in Gauss-Bonnet gravity that yield nonextremal NUT solutions to Einstein gravity having a curvature singularity at r=N in the limit {alpha}{yields}0. Indeed, we have nonextreme NUT solutions in 2+2k dimensions withmore » nontrivial fibration only when the 2k-dimensional base space is chosen to be CP{sup 2k}. We also find that the Gauss-Bonnet gravity has extremal NUT solutions whenever the base space is a product of 2-torii with at most a two-dimensional factor space of positive curvature. Indeed, when the base space has at most one positively curved two-dimensional space as one of its factor spaces, then Gauss-Bonnet gravity admits extreme NUT solutions, even though there a curvature singularity exists at r=N. We also find that one can have bolt solutions in Gauss-Bonnet gravity with any base space with factor spaces of zero or positive constant curvature. The only case for which one does not have bolt solutions is in the absence of a cosmological term with zero curvature base space.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
This standard covers alloy steel nuts for bolting for high-pressure and high-temperature service in nuclear and associated applications. This standard does not cover bar or other starting materials. The only implied special considerations for starting materials are that they be capable of passing the required tests when processed into finished products in accordance with this standard.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fukuoka, T.
Many studies have been devoted to investigate how the maximum stress occurring in the bolted joint could be reduced. Patterson and Kenny suggest that a modified nut with a straight bevel at the bearing surface is effective. However, they only dealt with M30, and estimations on the nut geometry had not been necessarily sufficient. In this study, an extensive finite element approach for solving general multi-body contact problem is proposed by incorporating a regularization method into stiffness matrices with singularity involved; thus, numerical analyses are executed to accurately determine the optimal shape of the modified nut for various design factors.more » A modified nut with a curved bevel is also treated, and it is concluded that the modified nuts are significantly effective for bolts with larger nominal diameter and fine pitch, and are practically useful compared to pitch modification and tapered thread methods.« less
Currie and Krikalev pull launch restraint bolts in the FGB/Zarya module
2013-11-19
STS088-359-037 (4-15 Dec. 1998) --- Astronaut Nancy J. Currie and cosmonaut Sergei K. Krikalev, both mission specialists, use rechargeable power tools to manipulate nuts and bolts on the Russian-built Zarya module. Astronaut Robert D. Cabana, mission commander, translates along the rail network in the background. The six STS-88 crew members had earlier entered the module through the U.S.-built Unity connecting module. Rails, straps and tools indicate the crewmembers had been working awhile when this photo was taken. Krikalev, representing the Russian Space Agency (RSA), has been assigned as a member of the three-man initial International Space Station (ISS) crew.
Steel shear strength of anchors with stand-off base plates : [technical summary].
DOT National Transportation Integrated Search
2013-09-01
Sign and signal structures are often connected : to concrete foundations through an annular base : plate set on anchor bolts. The plate is leveled : with nuts beneath it and secured with nuts : above it a double-nut connection. In many : in...
Tapping and listening: a new approach to bolt looseness monitoring
NASA Astrophysics Data System (ADS)
Kong, Qingzhao; Zhu, Junxiao; Ho, Siu Chun Michael; Song, Gangbing
2018-07-01
Bolted joints are among the most common building blocks used across different types of structures, and are often the key components that sew all other structural parts together. Monitoring and assessment of looseness in bolted structures is one of the most attractive topics in mechanical, aerospace, and civil engineering. This paper presents a new percussion-based non-destructive approach to determine the health condition of bolted joints with the help of machine learning. The proposed method is very similar to the percussive diagnostic techniques used in clinical examinations to diagnose the health of patients. Due to the different interfacial properties among the bolts, nuts and the host structure, bolted joints can generate unique sounds when it is excited by impacts, such as from tapping. Power spectrum density, as a signal feature, was used to recognize and classify recorded tapping data. A machine learning model using the decision tree method was employed to identify the bolt looseness level. Experiments demonstrated that the newly proposed method for bolt looseness detection is very easy to implement by ‘listening to tapping’ and the monitoring accuracy is very high. With the rapid in robotics, the proposed approach has great potential to be implemented with intimately weaving robotics and machine learning to produce a cyber-physical system that can automatically inspect and determine the health of a structure.
2010-09-13
CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, a left-side main separation bolt attaches the bottom of space shuttle Discovery to its external fuel tank in the Vehicle Assembly Building. As technicians were attaching the bolt Sept. 10, a bolt nut slipped back into Discovery's aft compartment. To retrieve it, technicians entered Discovery’s aft section through an access door. They then moved the nut back into position to finish attaching the bolt, which is used to separate Discovery from the external tank once the shuttle is in orbit. Discovery is scheduled to roll out to Launch Pad 39A later this month for its STS-133 launch to the International Space Station. Targeted to lift off Nov. 1, Discovery will take the Permanent Multipurpose Module (PMM) packed with supplies and critical spare parts, as well as Robonaut 2 (R2) to the station. Photo credit: NASA/Dimitri Gerondidakis
2010-09-13
CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, a Vehicle Assembly Building technician adjusts a left-side main separation bolt that attaches the bottom of space shuttle Discovery to its external fuel tank. As technicians were attaching the bolt Sept. 10, a bolt nut slipped back into Discovery's aft compartment. To retrieve it, technicians entered Discovery’s aft section through an access door. They then moved the nut back into position to finish attaching the bolt, which is used to separate Discovery from the external tank once the shuttle is in orbit. Discovery is scheduled to roll out to Launch Pad 39A later this month for its STS-133 launch to the International Space Station. Targeted to lift off Nov. 1, Discovery will take the Permanent Multipurpose Module (PMM) packed with supplies and critical spare parts, as well as Robonaut 2 (R2) to the station. Photo credit: NASA/Dimitri Gerondidakis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dehghani, M.H.; Research Institute for Astrophysics and Astronomy of Maragha; Khodam-Mohammadi, A.
First, we construct the Taub-NUT/bolt solutions of (2k+2)-dimensional Einstein-Maxwell gravity, when all the factor spaces of 2k-dimensional base space B have positive curvature. These solutions depend on two extra parameters, other than the mass and the NUT charge. These are electric charge q and electric potential at infinity V. We investigate the existence of Taub-NUT solutions and find that in addition to the two conditions of uncharged NUT solutions, there exist two extra conditions. These two extra conditions come from the regularity of vector potential at r=N and the fact that the horizon at r=N should be the outer horizonmore » of the NUT charged black hole. We find that the NUT solutions in 2k+2 dimensions have no curvature singularity at r=N, when the 2k-dimensional base space is chosen to be CP{sup 2k}. For bolt solutions, there exists an upper limit for the NUT parameter which decreases as the potential parameter increases. Second, we study the thermodynamics of these spacetimes. We compute temperature, entropy, charge, electric potential, action and mass of the black hole solutions, and find that these quantities satisfy the first law of thermodynamics. We perform a stability analysis by computing the heat capacity, and show that the NUT solutions are not thermally stable for even k's, while there exists a stable phase for odd k's, which becomes increasingly narrow with increasing dimensionality and wide with increasing V. We also study the phase behavior of the 4 and 6 dimensional bolt solutions in canonical ensemble and find that these solutions have a stable phase, which becomes smaller as V increases.« less
Hydrodynamics of bacteriophages
NASA Astrophysics Data System (ADS)
Katsamba, Panayiota; Lauga, Eric
2017-11-01
Bacteriophage viruses, one of the most abundant entities in our planet, lack the ability to move independently. Instead, they crowd fluid environments in anticipation of a random encounter with bacteria. Once they 'land' on their victim's surface, they eject their genetic material inside the host cell. A big fraction of phage species, however, first attach to the flagella of bacteria. Being immotile, these so-called flagellotropic phages still manage to reach the cell body for infection, and the process by which they move up the flagellum has intrigued the scientific community for over four decades. In 1973 Berg and Anderson proposed the nut-and-bolt mechanism in which, just like a nut being rotated moves along a bolt, the phage wraps itself around a flagellum possessing helical grooves (due to the helical rows of flagellin molecules) and exploits the rotation of the flagellum in order to passively travel along it. We provide here a first-principle theoretical model for this nut-and-bolt mechanism and show that it is able to predict experiment observations.
Filtration System for Removal of Depleted Uranium from Water.
1988-02-01
PVC, 3-Way 65 1 1" Pressure Control Valve, Posacon #677, PVC Body, EPDM Diaphragm, Threaded Union Ends Valves with Actuators 29 2 1" PVC 3-Way Multi...Gaskets/Clamps 14 24 1/2" x 2 1/4" LG. Machine Bolts 15 32 1,2" Hex Nuts 16 64 1/2" Washer 17 8 1 1" Full Face Black Rubber Gasket 36 8 5/8" x 3" LG...Machine Bolts 37 8 5/8" Hex Nuts 38 16 5/8" Washers 39 6 3" Full Face Black Rubber Gasket 45 8 1/2" x 2 1/4" Machine Bolts 78 6 1 1/2" K40 Gasket 79 2 2
Currie and Krikalev remove launch restraint bolts in FGB/Zarya module
1998-12-11
S88-E-5085 (12-11-98) --- Nancy J. Currie and Sergei Krikalev use rechargeable power tools to tighten and loosen nuts onboard the Russian-built Zarya module which they entered on Flight Day 8. The two are mission specialists, with Krikalev representing the Russian Space Agency (RSA). The photo was taken with an electronic still camera (ESC) at 05:28:53 GMT, Dec. 11.
NASA Technical Reports Server (NTRS)
Kerley, James J.
1987-01-01
The method of retroduction, adapted from the doctoral thesis of Dr. A. Croce, relies on a process of dialectic questioning that begins with the information sought, proceeds to Given items (either in the form of dimensions or limits of research). and to Known mathematical forms of analysis in design or to principles of study in research. Finally, analysis and synthesis are used to abstract the dielectic questions and to arrive at the information desired. This method is used to solve the engineering design problem of a beam and to determine why bolts and nuts vibrate apart. Both mathematical analysis and dialectic logical analysis are utilized. Results are provided of tests conducted to check the retroductive study of why and how nuts back off.
Comparison of release torques of tightened bolts in vacuum and air
NASA Technical Reports Server (NTRS)
Demorest, K. E.
1970-01-01
Various combinations of stainless steel, mild steel, and aluminum bolt-nut couples are tightened to 60 lb-ft in partial vacuum and in air. Results are given for tests with and without two lubricants /a fluorosilicone and a sodium silicate bonded dry-film/.
76 FR 19719 - Airworthiness Directives; Saab AB, Saab Aerosystems Model SAAB 2000 Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-08
... fretting corrosion; a detailed inspection of the actuator mounting bracket and shock struts for damage, cracks, and signs of corrosion; and doing corrective actions if necessary. Corrective actions include removing corrosion, replacing affected bolts with new bolts, tightening loose nuts, repairing, and...
Inedible Nuts and Non-Lightning Bolts
ERIC Educational Resources Information Center
Rynone, William
2010-01-01
In this article, the author provides detailed information on a wide variety of commonly used screws, bolts, and other fasteners. The information has been gathered in his engineering career and outside interests (maintenance on his car and airplane, and woodworking). The topic should be of interest to students and educators in many technical…
Coupling for joining a ball nut to a machine tool carriage
Gerth, Howard L.
1979-01-01
The present invention relates to an improved coupling for joining a lead screw ball nut to a machine tool carriage. The ball nut is coupled to the machine tool carriage by a plurality of laterally flexible bolts which function as hinges during the rotation of the lead screw for substantially reducing lateral carriage movement due to wobble in the lead screw.
Experimental analysis of thread movement in bolted connections due to vibrations
NASA Technical Reports Server (NTRS)
Ramey, G. ED; Jenkins, Robert C.
1994-01-01
The objective of this study was to identify the main design parameters contributing to loosening of bolts due to vibration and to identify their relative importance and degree of contribution to bolt loosening. Vibration testing was conducted on a shaketable with a controlled-random input in the dynamic testing laboratory of the Structural Test Division of MSFC. Test specimens which contained one test bolt were vibrated for a fixed amount of time and percentage of pre-load loss was measured. Each specimen tested implemented some combination of eleven design parameters as dictated by the design of experiment methodology employed. The eleven design parameters were: bolt size (diameter), lubrication on bolt, hole tolerance, initial pre-load, nut locking device, grip length, thread pitch, lubrication between mating materials, class of fit, joint configuration and mass of configuration. These parameters were chosen for this experiment because they are believed to be the design parameters having the greatest impact on bolt loosening. Two values of each design parameter were used and each combination of parameters tested was subjected to two different directions of vibration and two different g-levels of vibration. One replication was made for each test to gain some indication of experimental error and repeatability and to give some degree of statistical credibility to the data, resulting in a total of 96 tests being performed. The results of the investigation indicated that nut locking devices, joint configuration, fastener size, and mass of configuration were significant in bolt loosening due to vibration. The results of this test can be utilized to further research the complex problem of bolt loosening due to vibration.
2010-09-13
CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, space shuttle Discovery is attached to its external fuel tank and solid rocket boosters in the Vehicle Assembly Building. As technicians were attaching the left-side main separation bolt on the bottom of the shuttle to the external tank Sept. 10 a bolt nut slipped back into Discovery's aft compartment. To retrieve it, technicians entered Discovery’s aft section through an access door. They then moved the nut back into position to finish attaching the bolt, which is used to separate Discovery from the external tank once the shuttle is in orbit. Discovery is scheduled to roll out to Launch Pad 39A later this month for its STS-133 launch to the International Space Station. Targeted to lift off Nov. 1, Discovery will take the Permanent Multipurpose Module (PMM) packed with supplies and critical spare parts, as well as Robonaut 2 (R2) to the station. Photo credit: NASA/Dimitri Gerondidakis
2010-09-13
CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, technicians in the Vehicle Assembly Building inspect space shuttle Discovery, its external fuel tank and solid rocket boosters. As technicians were attaching the left-side main separation bolt on the bottom of the shuttle to the external tank Sept. 10 a bolt nut slipped back into Discovery's aft compartment. To retrieve it, technicians entered Discovery’s aft section through an access door. They then moved the nut back into position to finish attaching the bolt, which is used to separate Discovery from the external tank once the shuttle is in orbit. Discovery is scheduled to roll out to Launch Pad 39A later this month for its STS-133 launch to the International Space Station. Targeted to lift off Nov. 1, Discovery will take the Permanent Multipurpose Module (PMM) packed with supplies and critical spare parts, as well as Robonaut 2 (R2) to the station. Photo credit: NASA/Dimitri Gerondidakis
2010-09-13
CAPE CANAVERAL, Fla. -- At NASA's Kennedy Space Center in Florida, space shuttle Discovery is attached to its external fuel tank and solid rocket boosters in the Vehicle Assembly Building. As technicians were attaching the left-side main separation bolt on the bottom of the shuttle to the external tank Sept. 10 a bolt nut slipped back into Discovery's aft compartment. To retrieve it, technicians entered Discovery’s aft section through an access door. They then moved the nut back into position to finish attaching the bolt, which is used to separate Discovery from the external tank once the shuttle is in orbit. Discovery is scheduled to roll out to Launch Pad 39A later this month for its STS-133 launch to the International Space Station. Targeted to lift off Nov. 1, Discovery will take the Permanent Multipurpose Module (PMM) packed with supplies and critical spare parts, as well as Robonaut 2 (R2) to the station. Photo credit: NASA/Dimitri Gerondidakis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Galambos, Paul C.; Crenshaw, Thomas B.; Nishida, Erik E.
The various technologies presented herein relate to a sensor for measurement of high forces and/or high load shock rate(s), whereby the sensor utilizes silicon as the sensing element. A plate of Si can have a thinned region formed therein on which can be formed a number of traces operating as a Wheatstone bridge. The brittle Si can be incorporated into a layered structure comprising ductile and/or compliant materials. The sensor can have a washer-like configuration which can be incorporated into a nut and bolt configuration, whereby tightening of the nut and bolt can facilitate application of a compressive preload uponmore » the sensor. Upon application of an impact load on the bolt, the compressive load on the sensor can be reduced (e.g., moves towards zero-load), however the magnitude of the preload can be such that the load on the sensor does not translate to tensile stress being applied to the sensor.« less
Tensile testing grips ensure uniform loading of bimetal tubing specimens
NASA Technical Reports Server (NTRS)
Driscol, S. D.; Hunt, V.
1968-01-01
Tensile testing grip uniformly distributes stresses to the internal and external tube of bimetal tubing specimens. The grip is comprised of a slotted external tube grip, a slotted internal tube grip, a machine bolt and nut, an internal grip expansion cone, and an external grip compression nut.
Solid Rocket Booster Hydraulic Pump Port Cap Joint Load Testing
NASA Technical Reports Server (NTRS)
Gamwell, W. R.; Murphy, N. C.
2004-01-01
The solid rocket booster uses hydraulic pumps fabricated from cast C355 aluminum alloy, with 17-4 PH stainless steel pump port caps. Corrosion-resistant steel, MS51830 CA204L self-locking screw thread inserts are installed into C355 pump housings, with A286 stainless steel fasteners installed into the insert to secure the pump port cap to the housing. In the past, pump port cap fasteners were installed to a torque of 33 Nm (300 in-lb). However, the structural analyses used a significantly higher nut factor than indicated during tests conducted by Boeing Space Systems. When the torque values were reassessed using Boeing's nut factor, the fastener preload had a factor of safety of less than 1, with potential for overloading the joint. This paper describes how behavior was determined for a preloaded joint with a steel bolt threaded into steel inserts in aluminum parts. Finite element models were compared with test results. For all initial bolt preloads, bolt loads increased as external applied loads increased. For higher initial bolt preloads, less load was transferred into the bolt, due to external applied loading. Lower torque limits were established for pump port cap fasteners and additional limits were placed on insert axial deformation under operating conditions after seating the insert with an initial preload.
NASA Technical Reports Server (NTRS)
1999-01-01
Marshall Space Flight Center (MSFC) has developed a specially-designed nut, called the Quick-Connect Nut, for quick and easy assembly of components in the harsh environment of space, as in assembly of International Space Station. The design permits nuts to be installed simply by pushing them onto standard bolts, then giving a quick twist. To remove, they are unscrewed like conventional nuts. Possible applications include the mining industry for erecting support barriers, assembling underwater oil drilling platforms, fire-fighting equipment, scaffolding, assembly-line machinery, industrial cranes, and even changing lug nuts on race cars. The speed of assembly can make the difference between life and death in different aspects of life on Earth.
49 CFR 572.86 - Test conditions and dummy adjustment.
Code of Federal Regulations, 2012 CFR
2012-10-01
... lying on a horizontal surface and the neck assembly mounted and shoulders on the edge of the surface... surface with the shoulders on the edge of the surface, mount the head and tighten the head bolt and nut... upper arm and tighten firmly the adjustment bolts for the shoulder joint with the upper arm placed in a...
49 CFR 572.86 - Test conditions and dummy adjustment.
Code of Federal Regulations, 2014 CFR
2014-10-01
... lying on a horizontal surface and the neck assembly mounted and shoulders on the edge of the surface... surface with the shoulders on the edge of the surface, mount the head and tighten the head bolt and nut... upper arm and tighten firmly the adjustment bolts for the shoulder joint with the upper arm placed in a...
49 CFR 572.86 - Test conditions and dummy adjustment.
Code of Federal Regulations, 2011 CFR
2011-10-01
... lying on a horizontal surface and the neck assembly mounted and shoulders on the edge of the surface... surface with the shoulders on the edge of the surface, mount the head and tighten the head bolt and nut... upper arm and tighten firmly the adjustment bolts for the shoulder joint with the upper arm placed in a...
49 CFR 572.86 - Test conditions and dummy adjustment.
Code of Federal Regulations, 2010 CFR
2010-10-01
... lying on a horizontal surface and the neck assembly mounted and shoulders on the edge of the surface... surface with the shoulders on the edge of the surface, mount the head and tighten the head bolt and nut... upper arm and tighten firmly the adjustment bolts for the shoulder joint with the upper arm placed in a...
49 CFR 572.86 - Test conditions and dummy adjustment.
Code of Federal Regulations, 2013 CFR
2013-10-01
... lying on a horizontal surface and the neck assembly mounted and shoulders on the edge of the surface... surface with the shoulders on the edge of the surface, mount the head and tighten the head bolt and nut... upper arm and tighten firmly the adjustment bolts for the shoulder joint with the upper arm placed in a...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-10-14
... the fitting and wing structure. Checking the nuts with a suitable torque spanner to the specifications in the torque figures shown in Table 2. of the Accomplishment Instructions of BAE SYSTEMS (OPERATIONS... installed, and Doing either an ultrasonic inspection for damaged bolts or torque check of the tension bolts...
Reversible fastener clamp load monitor with continuous visual or remote readout
NASA Astrophysics Data System (ADS)
Hodge, Malcolm H.; Kausel, Theodore C., Jr.; Begley, Matthew R.
1998-03-01
SIMS has developed a simple means for detecting and monitoring both absolute and relative clamp load, or bolt tension, in fastener systems. More than twenty-five percent of automotive failures are known to be due to undetected loss of fastener clamp load. While the equivalent aerospace maintenance statistics are not known, the average automobile has 3,500 fasteners while a Boeing 747 has closer to one million. It is therefore anticipated that the new SensaBolt clamp load tracking system could find wide applications in the aerospace arena. We describe a visually-evident and retrofitted clamp load monitoring design which is based on the differential joint substrate compression at, and immediately adjacent to, the fastener location. This intrinsically-accurate indicator does not necessarily require alteration in either the bolt or nut geometries, thereby facilitating product introduction and retrofit in aging aircraft applications. In addition, SensaBolt's sole reliance on substrate compression renders it more accurate then torque wrench or turn-of-nut techniques. Readout may be accomplished by any of three principal methods: for those applications with ease of access to the sensor, loss of tension can be determined by direct visual inspection. Application of a standard wrench can then be made to restore the fastener's proper tightness, per the SensaBolt indicators. In those instances where line-of-sight is unimpeded and more formal inspection is desired, the SensaBolt may be interrogated by a laser scanner bar code reader. Finally, SensaBolt may be addressed by the SIMS fiber optic harness for those instances where full-time remote interrogation is desired.
Faying Surface Lubrication Effects on Nut Factors
NASA Technical Reports Server (NTRS)
Taylor, Deneen M.; Morrison, Raymond F.
2006-01-01
Bolted joint analysis typically is performed using nut factors derived from textbooks and procedures from program requirement documents. Joint specific testing was performed for a critical International Space Station (ISS) joint. Test results indicate that for some configurations the nut factor may be significantly different than accepted textbook values. This paper presents results of joint specific testing to aid in determining if joint specific testing should be performed to insure required preloads are obtained.
Standard specification for carbon and alloy steel nuts. ASTM standard
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
This specification is under the jurisdiction of ASTM Committee F-16 on Fasteners and is the responsibility of Subcommittee F16.02 on Steel Bolts, Nuts, Rivets, and Washers. Current edition approved Dec. 10, 1997. Published July 1998. Originally published as A 563-66. Last previous edition A 563-96.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
This standard covers alloy steel nuts for bolting for high-pressure and high-temperature service in nuclear and associated applications. This standard does not cover bar or other starting materials. The only implied special considerations for starting materials are that they be capable of passing the required tests when processed into finished products in accordance with this standard. Material shall conform to the requirements of ASME SA-194; to the requirements of the ASME Boiler and Pressure Vessel Code (ASME Code), Section III, Article NB-2000; to the requirements of NE E 8-18; and to the additional requirements of this standard.
Heating and cooling gas-gun targets: nuts and bolts
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gustavsen, Richard L; Bartram, Brian D; Gehr, Russell J
The nuts and bolts of a system used to heat and cool gas-gun targets is described. We have now used the system for more than 35 experiments, all of which have used electromagnetic gauging. Features of the system include a cover which is removed (remotely) just prior to projectile impact and the widespread use of metal/polymer insulations. Both the cover and insulation were required to obtain uniform temperatures in samples with low thermal conductivity. The use of inexpensive video cameras to make remote observations of the cover removal was found to be very useful. A brief catalog of useful glue,more » adhesive tape, insulation, and seal materials is given.« less
Standard specification for anchor bolts, steel, 36, 55, and 105-ksi yield strength. ASTM standard
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1998-07-01
This specification is under the jurisdiction of ASTM Committee F-16 on Fasteners and is the direct responsibility of Subcommittee F16.02 on Steel Bolts, Nuts, Rivets, and Washers. Current edition approved Dec. 10, 1997 and published July 1998. Originally published as F 1554-94. Last previous edition was F 1554-94.
Experimental analysis of thread movement in bolted connections due to vibrations
NASA Technical Reports Server (NTRS)
Ramsey, G. ED; Jenkins, Robert C.
1995-01-01
This is the final report of research project NAS8-39131 #33 sponsored by NASA's George C. Marshall Space Flight Center (MSFC) and carried out by the Civil Engineering Department of Auburn University (Auburn, Alabama) and personnel of MSFC. The objective of this study was to identify the main design parameters contributing to the loosening of bolts due to vibration and to identify their relative importance and degree of contribution to bolt loosening. Vibration testing was conducted on a shaketable with a controlled-random input in the dynamic testing laboratory of the Structural Test Division of MSFC. Test specimens which contained one test bolt were vibrated for a fixed amount of time and a percentage of pre-load loss was measured. Each specimen tested implemented some combination of eleven design parameters as dictated by the design of experiment methodology employed. The eleven design parameters were: bolt size (diameter), lubrication on bolt, hole tolerance, initial pre-load, nut locking device, grip length, thread pitch, lubrication between mating materials, class of fit, joint configuration, and mass of configuration. These parameters were chosen for this experiment because they are believed to be the design parameters having the greatest impact on bolt loosening. Two values of each design parameter were used and each combination of parameters tested was subjected to two different directions of vibration and two different g-levels of vibration. One replication was made for each test to gain some indication of experimental error and repeatability and to give some degree of statistical credibility to the data, resulting in a total of 96 tests being performed. The results of the investigation indicated that nut locking devices, joint configuration, fastener size, and mass of configuration were significant in bolt loosening due to vibration. The results of this test can be utilized to further research the complex problem of bolt loosening due to vibration.
Silicon force sensor and method of using the same
DOE Office of Scientific and Technical Information (OSTI.GOV)
Galambos, Paul C.; Crenshaw, Thomas B.; Nishida, Erik E.
The various technologies presented herein relate to a sensor for measurement of high forces and/or high load shock rate(s), whereby the sensor utilizes silicon as the sensing element. A plate of Si can have a thinned region formed therein on which can be formed a number of traces operating as a Wheatstone bridge. The brittle Si can be incorporated into a layered structure comprising ductile and/or compliant materials. The sensor can have a washer-like configuration which can be incorporated into a nut and bolt configuration, whereby tightening of the nut and bolt can facilitate application of a compressive preload uponmore » the sensor. Upon application of an impact load on the bolt, the compressive load on the sensor can be reduced (e.g., moves towards zero-load), however the magnitude of the preload can be such that the load on the sensor does not translate to tensile stress being applied to the sensor.« less
1999-10-12
Marshall Space Flight Center (MSFC) has developed a specially-designed nut, called the Quick-Connect Nut, for quick and easy assembly of components in the harsh environment of space, as in assembly of International Space Station. The design permits nuts to be installed simply by pushing them onto standard bolts, then giving a quick twist. To remove, they are unscrewed like conventional nuts. Possible applications include the mining industry for erecting support barriers, assembling underwater oil drilling platforms, fire-fighting equipment, scaffolding, assembly-line machinery, industrial cranes, and even changing lug nuts on race cars. The speed of assembly can make the difference between life and death in different aspects of life on Earth.
Art across the Curriculum: Out of the Box
ERIC Educational Resources Information Center
Sartorius, Tara Cady
2009-01-01
Rick Beck works in cast glass; his large-scale work ranges in scale from 15 inches to around 7 feet tall. His medium--glass--makes the scale of Beck's pieces very impressive. He is probably best-known for his oversized cast glass sculptures of common hardware: nuts, bolts, screws, measuring spoons, saws, eating utensils, eye hooks, wing nuts and…
Tooling Converts Stock Bearings To Custom Bearings
NASA Technical Reports Server (NTRS)
Fleenor, E. N., Jr.
1983-01-01
Technique for reworking stock bearings saves time and produces helicopter-rotor bearings ground more precisely. Split tapered ring at one end of threaded bolt expands to hold inside of inner race bearing assembly; nut, at other end of bolt, adjusts amount of spring tension. Piece of hardware grasps bearing firmly without interfering with grinding operation. Operation produces bearing of higher quality than commercially available bearings.
Preload Loss in a Spacecraft Fastener via Vibration-Induced Unwinding
NASA Technical Reports Server (NTRS)
DellaCorte, Christopher; Howard, S. Adam; Hess, Daniel P.
2018-01-01
Sound engineering practice requires that fasteners and bolted joints maintain preload in service. NASA recently concluded a series of vibration tests of a multicomponent structure intended to simulate an upper stage section of a launch vehicle. The stacked components were joined through six circumferentially placed bolted cup-cone-style pyrotechnic joint mechanisms designed to share spacecraft structural loads and then enable separation during ascent. Over the course of the vibration test campaign, all six bolted cup-cone mechanisms experienced some degree of preload loss with two mechanisms losing half of their original bolt preload. A subsequent forensic anomaly investigation concluded that vibration-induced unwinding of the preload nut-and-bolt assemblies occurred despite the use of safety wire and high levels of thread friction. A series of experiments were done to better understand how large, heavily preloaded fasteners could unwind. Additionally, thread friction torque was measured and the fastener locking capability of safety wire was evaluated. The friction coefficient between the clamped cup-cone components was characterized and finally a highly instrumented mechanism-level vibration test was done to reproduce the unwinding phenomenon to better understand the mechanism's behavior. The conclusion drawn was that vibration and structural forces led to relative motion (sliding) of the clamped components, resulting in self-loosening and unwinding effects on the nut-and-bolt assembly. To counter this phenomenon, more effective fastener locking methodologies were recommended and a follow-on effort was initiated to quantify the relationship between preload, component motion, and resulting unwinding forces. It is hoped that elucidation of these effects can be used to design more effective fastener locking features.
NASA Technical Reports Server (NTRS)
Ahmed, Rafiq (Inventor); Wingate, Robert J. (Inventor)
2005-01-01
In the aerospace field spacecraft components are held together by separation systems until a specific time when they must be separated or deployed. Customarily a threaded joining bolt engages one of the components to be joined, and a threaded nut is placed on that bolt against the other component so they can be drawn together by a releasable locking assembly. The releasable locking assembly herein includes a plunger having one end coupled to one end of a plunger bolt. The other end is flanged to abut and compress a coil spring when the plunger is advanced toward the interface plane between the two components. When the plunger is so advanced toward the interface plane, the end of the plunger bolt can be connected to the joining bolt. Thus during retraction the joining bolt is drawn to one side of the interface plane by the force of the expanding spring.
NASA Technical Reports Server (NTRS)
Ahmed, Rafiq (Inventor); Wingate, Robert J. (Inventor)
2005-01-01
In the aerospace field spacecraft components are held together by separation systems until a specific time when they must be separated or deployed. Customarily a threaded joining bolt engages one of the components to be joined, and a threaded nut is placed on that bolt against the other component so they can be drawn together by a releasable locking assembly. The releasable locking assembly herein includes a plunger having one end coupled to one end of a plunger bolt. The other end is flanged to abut and compress a coil spring when the plunger is advanced toward the interface plane between the two components. When the plunger is so advanced toward the interface plane, the end of the plunger bolt can be connected to the joining bolt. Thus during retraction the joining bolt is drawn to one side of the interface plane by the force of the expanding spring.
Ballas, Gary J.; Fife, Alex Blair; Ganz, Israel
1998-01-01
A shroud for a nuclear reactor is described. In one embodiment, the shroud includes first and second shroud sections, and each shroud section includes a substantially cylindrical main body having a first end and a second end. With respect to each shroud section, a flange is located at the main body first end, and the flange has a plurality of bolt openings therein and a plurality of scalloped regions. The first shroud section is welded to the second shroud section, and at least some of the bolt openings in the first shroud section flange align with respective bolt openings in the second shroud section flange. In the event that the onset of inter-granular stress corrosion cracking is ever detected in the weld between the shroud section, bolts are inserted through bolt openings in the first shroud section flange and through aligned bolt openings the second shroud section flange. Each bolt, in one embodiment, has a shank section and first and second threaded end sections. Nuts are threadedly engaged to the threaded end sections and tightened against the respective flanges.
High powered rocketry: design, construction, and launching experience and analysis
NASA Astrophysics Data System (ADS)
Paulson, Pryce; Curtis, Jarret; Bartel, Evan; Owens Cyr, Waycen; Lamsal, Chiranjivi
2018-01-01
In this study, the nuts and bolts of designing and building a high powered rocket have been presented. A computer simulation program called RockSim was used to design the rocket. Simulation results are consistent with time variations of altitude, velocity, and acceleration obtained in the actual flight. The actual drag coefficient was determined by using altitude back-tracking method and found to be 0.825. Speed of the exhaust determined to be 2.5 km s-1 by analyzing the thrust curve of the rocket. Acceleration in the coasting phase of the flight, represented by the second-degree polynomial of a small leading coefficient, have been found to approach ‘-g’ asymptotically.
Spline screw payload fastening system
NASA Technical Reports Server (NTRS)
Vranish, John M. (Inventor)
1993-01-01
A system for coupling an orbital replacement unit (ORU) to a space station structure via the actions of a robot and/or astronaut is described. This system provides mechanical and electrical connections both between the ORU and the space station structure and between the ORU and the ORU and the robot/astronaut hand tool. Alignment and timing features ensure safe, sure handling and precision coupling. This includes a first female type spline connector selectively located on the space station structure, a male type spline connector positioned on the orbital replacement unit so as to mate with and connect to the first female type spline connector, and a second female type spline connector located on the orbital replacement unit. A compliant drive rod interconnects the second female type spline connector and the male type spline connector. A robotic special end effector is used for mating with and driving the second female type spline connector. Also included are alignment tabs exteriorally located on the orbital replacement unit for berthing with the space station structure. The first and second female type spline connectors each include a threaded bolt member having a captured nut member located thereon which can translate up and down the bolt but are constrained from rotation thereabout, the nut member having a mounting surface with at least one first type electrical connector located on the mounting surface for translating with the nut member. At least one complementary second type electrical connector on the orbital replacement unit mates with at least one first type electrical connector on the mounting surface of the nut member. When the driver on the robotic end effector mates with the second female type spline connector and rotates, the male type spline connector and the first female type spline connector lock together, the driver and the second female type spline connector lock together, and the nut members translate up the threaded bolt members carrying the first type electrical connector up to the complementary second type connector for interconnection therewith.
The design and development of a spacecraft appendage tie down mechanism
NASA Technical Reports Server (NTRS)
Nygren, W. D.; Head, R.
1985-01-01
The design and evolution is described of a spacecraft Appendage Tie Down Mechanism (ATDM). Particular emphasis is paid to the mechanical aspects of using dry lubricants to increase the efficiency of acme threads and worm gearing. The ATDM consists of five major components. These are a dc torque motor, a worm gear speed reducer, the tension bolt (or T-bolt), nut capture and centering jaws and the capture nut. In addition, there are several minor components such as limit switch assemblies and an antibackdrive mechanism which couples the drive motor to the worm shaft. A development model of the ATDM in various configurations was under test for some time. In its latest version, it has successfully completed thermal vacuum testing, vibration testing, and extended life testing.
NASA Astrophysics Data System (ADS)
Omar, R.; Rani, M. N. Abdul; Yunus, M. A.; Mirza, W. I. I. Wan Iskandar; Zin, M. S. Mohd
2018-04-01
A simple structure with bolted joints consists of the structural components, bolts and nuts. There are several methods to model the structures with bolted joints, however there is no reliable, efficient and economic modelling methods that can accurately predict its dynamics behaviour. Explained in this paper is an investigation that was conducted to obtain an appropriate modelling method for bolted joints. This was carried out by evaluating four different finite element (FE) models of the assembled plates and bolts namely the solid plates-bolts model, plates without bolt model, hybrid plates-bolts model and simplified plates-bolts model. FE modal analysis was conducted for all four initial FE models of the bolted joints. Results of the FE modal analysis were compared with the experimental modal analysis (EMA) results. EMA was performed to extract the natural frequencies and mode shapes of the test physical structure with bolted joints. Evaluation was made by comparing the number of nodes, number of elements, elapsed computer processing unit (CPU) time, and the total percentage of errors of each initial FE model when compared with EMA result. The evaluation showed that the simplified plates-bolts model could most accurately predict the dynamic behaviour of the structure with bolted joints. This study proved that the reliable, efficient and economic modelling of bolted joints, mainly the representation of the bolting, has played a crucial element in ensuring the accuracy of the dynamic behaviour prediction.
Behavior of a tapered hub flange with a bolted flat cover in transient temperature field
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sawa, T.; Nakagomi, Y.; Hirose, T.
1996-02-01
When bolted flange connections with gaskets are used in mechanical structures such as pipe connections, bolted covers of casks, and pressure vessels in nuclear and chemical plants and cylinder heads in internal combustion engines, they are usually subjected to transient thermal conditions. An experimental and analytical study was made on a bolted connection subjected to thermal loading. The connection consists of an aluminum alloy tapered hub flange and a flat cover, including a gasket fastened by steel bolts and nuts. Temperature distribution in the connection was measured with thermocouples, and the axial bolt force, the maximum bolt stress, and themore » hub stress were measured by strain gages under a thermal condition that the inner surface of the flanges was heated and the outer surfaces of the flanges and the cover were held at room temperature. Finite difference analysis was made to obtain the temperature distributions in the connection due to a transient thermal condition. This paper demonstrates the method for obtaining an increment in axial bolt force and the maximum bolt stress. In all cases, the analytical results were fairly consistent with the experimental results.« less
77 FR 11416 - Airworthiness Directives; The Boeing Company Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-27
.... This proposed AD would require modifying COS boxes by installing new brackets, stiffeners, and hardware... installing new brackets, stiffeners, and hardware (bolts, washers, and nuts) as needed. FAA's Determination...
Cleanup Verification Package for the 300-18 Waste Site
DOE Office of Scientific and Technical Information (OSTI.GOV)
J. M. Capron
This cleanup verification package documents completion of remedial action for the 300-18 waste site. This site was identified as containing radiologically contaminated soil, metal shavings, nuts, bolts, and concrete.
High-Torque, Lightweight, Pneumatically Driven Wrench For Small Spaces
NASA Technical Reports Server (NTRS)
Miller, Thomas W.
1995-01-01
Pneumatically driven wrench provides torque up to 3,000 lb. per ft. in small space. Designed to reach into 2.6 x 2.75 x 6 in. pocket. Weighs approximately 25 lbs. Includes reversible pneumatic motor (electric motor could be used instead) and slip clutch. Also includes device indicating total angle through which wrench turned bolt or nut. This feature used for turn-of-the-nut tightening method.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ballas, G.J.; Fife, A.B.; Ganz, I.
1998-04-07
A shroud for a nuclear reactor is described. In one embodiment, the shroud includes first and second shroud sections, and each shroud section includes a substantially cylindrical main body having a first end and a second end. With respect to each shroud section, a flange is located at the main body first end, and the flange has a plurality of bolt openings therein and a plurality of scalloped regions. The first shroud section is welded to the second shroud section, and at least some of the bolt openings in the first shroud section flange align with respective bolt openings inmore » the second shroud section flange. In the event that the onset of inter-granular stress corrosion cracking is ever detected in the weld between the shroud section, bolts are inserted through bolt openings in the first shroud section flange and through aligned bolt openings the second shroud section flange. Each bolt, in one embodiment, has a shank section and first and second threaded end sections. Nuts are threadedly engaged to the threaded end sections and tightened against the respective flanges. 4 figs.« less
Ballas, G.J.; Fife, A.B.; Ganz, I.
1998-04-07
A shroud for a nuclear reactor is described. In one embodiment, the shroud includes first and second shroud sections, and each shroud section includes a substantially cylindrical main body having a first end and a second end. With respect to each shroud section, a flange is located at the main body first end, and the flange has a plurality of bolt openings therein and a plurality of scalloped regions. The first shroud section is welded to the second shroud section, and at least some of the bolt openings in the first shroud section flange align with respective bolt openings in the second shroud section flange. In the event that the onset of inter-granular stress corrosion cracking is ever detected in the weld between the shroud section, bolts are inserted through bolt openings in the first shroud section flange and through aligned bolt openings the second shroud section flange. Each bolt, in one embodiment, has a shank section and first and second threaded end sections. Nuts are threadedly engaged to the threaded end sections and tightened against the respective flanges. 4 figs.
The Nuts and Bolts of Product Service. The Product Service Industry. Resources in Technology.
ERIC Educational Resources Information Center
Technology Teacher, 1991
1991-01-01
Reviews repair and maintenance services, qualifications for technicians, sociocultural impacts of customer service, and consumer and manufacturer responsibilities. Presents a technology learning activity on product failure. (SK)
Source of the slippage in the universal joints of the Hoffmann external fixator.
Drijber, F L; Finlay, J B; Moroz, T K; Rorabeck, C H
1990-01-01
An investigation was conducted to determine what improvements in the resistance to slippage could be obtained in selected interfaces (rod/clip torsional, cheek/bowl and cheek/clip) of the Hoffmann external fixator. The modification involved changing the standard wing-nut clamp for a bolt with a thread of 7 mm and a 1 mm pitch and placing an FAG 28-303 thrust-bearing (needle roller and cage assembly) between the bolt and the cheek. The results showed a significant improvement in the slippage values of all interfaces; increases of approximately six times were obtained at all torque values of the wing-nut clamp or fastener tested. Such improvements would markedly increase the reliability of external fixation systems and thus reduce the incidence of loss-of-reduction of fracture due to slippage of the universal joint.
Hydraulic Apparatus for Mechanical Testing of Nuts
NASA Technical Reports Server (NTRS)
Hinkel, Todd J.; Dean, Richard J.; Hacker, Scott C.; Harrington, Douglas W.; Salazar, Frank
2004-01-01
The figure depicts an apparatus for mechanical testing of nuts. In the original application for which the apparatus was developed, the nuts are of a frangible type designed for use with pyrotechnic devices in spacecraft applications in which there are requirements for rapid, one-time separations of structures that are bolted together. The apparatus can also be used to test nonfrangible nuts engaged without pyrotechnic devices. This apparatus was developed to replace prior testing systems that were extremely heavy and immobile and characterized by long setup times (of the order of an hour for each nut to be tested). This apparatus is mobile, and the setup for each test can now be completed in about five minutes. The apparatus can load a nut under test with a static axial force of as much as 6.8 x 10(exp 5) lb (3.0 MN) and a static moment of as much as 8.5 x 10(exp 4) lb in. (9.6 x 10(exp 3) N(raised dot)m) for a predetermined amount of time. In the case of a test of a frangible nut, the pyrotechnic devices can be exploded to break the nut while the load is applied, in which case the breakage of the nut relieves the load. The apparatus can be operated remotely for safety during an explosive test. The load-generating portion of the apparatus is driven by low-pressure compressed air; the remainder of the apparatus is driven by 110-Vac electricity. From its source, the compressed air is fed to the apparatus through a regulator and a manually operated valve. The regulated compressed air is fed to a pneumatically driven hydraulic pump, which pressurizes oil in a hydraulic cylinder, thereby causing a load to be applied via a hydraulic nut (not to be confused with the nut under test). During operation, the hydraulic pressure is correlated with the applied axial load, which is verified by use of a load cell. Prior to operation, one end of a test stud (which could be an ordinary threaded rod or bolt) is installed in the hydraulic nut. The other end of the test stud passes through a bearing plate; a load cell is slid onto that end, and then the nut to be tested is threaded onto that end and tightened until the nut and load cell press gently against the bearing plate.
ERIC Educational Resources Information Center
Franzen, Mark; Gorrell, Kyle
2002-01-01
Based on one school district's experience, discusses raised access flooring systems for schools. Addresses the nuts and bolts of such flooring systems, integrating an air delivery system below the flooring, advantages of floor-level air supply, and design issues. (EV)
A simple and inexpensive external fixator.
Noor, M A
1988-11-01
A simple and inexpensive external fixator has been designed. It is constructed of galvanized iron pipe and mild steel bolts and nuts. It can easily be manufactured in a hospital workshop with a minimum of tools.
Motor-driven screwing and transporting tool for reactor pressure vessel head retaining fastenings
DOE Office of Scientific and Technical Information (OSTI.GOV)
Scholz, M.
1977-09-13
The invention concerns a motor-driven screwing and transporting tool for tightening or loosening the threaded studs and associated tightening nuts of the head bolting of pressure vessels. After the tightening nuts are loosened or before they are tightened, the weight of the studs is taken over by rotating bearings that can be lifted, so that the studs with their tightening nuts can be screwed in or out, the screw threads of the studs being thus weight-relieved. The invention is intended primarily for nuclear reactor pressure vessels. 21 claims, 6 figures.
Effect of thread shape on screw stress concentration by photoelastic measurements
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dragoni, E.
1994-11-01
The screw stress concentration for six nut-bolt connections embodying three different thread profiles and two nut shapes is measured photoelastically. Buttress (nearly zero flank angle), trapezoidal (15-deg flank angle), and triangular (30-deg flank angle) thread forms are examined in combination with standard and lip-type nuts. The effect of the thread profile on the screw stress concentration appears to be dependent upon the kind of nut considered. If the fastening incorporates a standard nut, the buttress thread is stronger than the triangular one, which, in turn, behaves better than the trapezoidal contour. The improvement is roughly a 20% reduction in themore » stress concentration factor from the trapezoidal to the buttress thread. In the case of lip nut, conversely, this tendency is somewhat reversed, with the trapezoidal thread performing slightly (but not decidedly) better than the other two shapes. Finally, averaged over all three thread forms, the lip nut exhibits a stress concentration factor which is about 50% lower than that of the standard nut.« less
NASA Technical Reports Server (NTRS)
Belrose, Charles R. (Inventor)
1994-01-01
A saddle clamp assembly is presented. The assembly is comprised of a hollow cylindrical body centered about a longitudinal axis and being diametrically split into semicircular top and bottom sections. Each section has a pair of connection flanges, at opposite ends, that project radially outward. A pair of bolts are retained on the top section flanges and are threadable into nuts retained on the bottom section flanges. A base member is anchored to a central underside portion of the bottom clamp body section and has a pair of connection tabs positioned beneath the bottom clamp body section connection flanges on opposite sides of the clamp axis. A pair of bolts are retained on the base member connection tabs and are threadable into a pair of nuts retainable on a support structure. The connection tab and connection flanges on each side of the clamp body are axially offset in a manner permitting downward installation/removable tool access to the lower bolts past the connection flanges. An elongated retention tether is used to connect the top clamp body section to the balance of the clamp assembly. This prevents loss of the top clamp body section when it is removed from the bottom clamp body section.
Full-Scale Evaluation of DuraDeck (registered trademark) and MegaDeck (trademark) Matting Systems
2013-07-01
plates studded with threaded bolts were placed ERDC/GSL TR-13-27 10 underneath two pre-drilled corners of the panel. The plates were positioned so...metal plates studded with threaded ERDC/GSL TR-13-27 4 Figure 1. DuraDeck® mat panel, top surface. Figure 2. DuraDeck® mat panel, bottom surface...ERDC/GSL TR-13-27 5 bolts , as shown in Figure 3, underneath the mat corners and then installing special connector nuts from the top surface
Bzorgi, Fariborz M.
2010-03-09
An apparatus for clipping a protrusion of material is provided. The protrusion may, for example, be a bolt head, a nut, a rivet, a weld bead, or a temporary assembly alignment tab protruding from a substrate surface of assembled components. The apparatus typically includes a cleaver having a cleaving edge and a cutting blade having a cutting edge. Generally, a mounting structure configured to confine the cleaver and the cutting blade and permit a range of relative movement between the cleaving edge and the cutting edge is provided. Also typically included is a power device coupled to the cutting blade. The power device is configured to move the cutting edge toward the cleaving edge. In some embodiments the power device is activated by a momentary switch. A retraction device is also generally provided, where the retraction device is configured to move the cutting edge away from the cleaving edge.
Remotely serviced filter and housing
Ross, M.J.; Zaladonis, L.A.
1987-07-22
A filter system for a hot cell comprises a housing adapted for input of air or other gas to be filtered, flow of the air through a filter element, and exit of filtered air. The housing is tapered at the top to make it easy to insert a filter cartridge holds the filter element while the air or other gas is passed through the filter element. Captive bolts in trunnion nuts are readily operated by electromechanical manipulators operating power wrenches to secure and release the filter cartridge. The filter cartridge is adapted to make it easy to change a filter element by using a master-slave manipulator at a shielded window station. 6 figs.
Monitoring of Pre-Load on Rock Bolt Using Piezoceramic-Transducer Enabled Time Reversal Method.
Huo, Linsheng; Wang, Bo; Chen, Dongdong; Song, Gangbing
2017-10-27
Rock bolts ensure structural stability for tunnels and many other underground structures. The pre-load on a rock bolt plays an important role in the structural reinforcement and it is vital to monitor the pre-load status of rock bolts. In this paper, a rock bolt pre-load monitoring method based on the piezoceramic enabled time reversal method is proposed. A lead zirconate titanate (PZT) patch transducer, which works as an actuator to generate stress waves, is bonded onto the anchor plate of the rock bolt. A smart washer, which is fabricated by sandwiching a PZT patch between two metal rings, is installed between the hex nut and the anchor plate along the rock bolt. The smart washer functions as a sensor to detect the stress wave. With the increase of the pre-load values on the rock bolt, the effective contact surface area between the smart washer and the anchor plate, benefiting the stress wave propagation crossing the contact surface. With the help of time reversal technique, experimental results reveal that the magnitude of focused signal clearly increases with the increase of the pre-load on a rock bolt before the saturation which happens beyond a relatively high value of the pre-load. The proposed method provides an innovative and real time means to monitor the pre-load level of a rock bolt. By employing this method, the pre-load degradation process on a rock bolt can be clearly monitored. Please note that, currently, the proposed method applies to only new rock bolts, on which it is possible to install the PZT smart washer.
Testing and Evaluation of the Bear Medical Systems, Inc. Bear 33 Volume Ventilator System
1990-12-01
approved for publication. RICHARD J. KNECHT, Lt Col, USAF, NC ROGER L STORK , Col, USAF, BSC Project Scientist Chief, Crew Systems Branch EORCHENDER...no problems. After the vibration tests, a visual inspection of the humidifier revealed that a screw and metal clip from a terminal on the incoming...hexagonal J-bolt nuts, which secure the sled to the litter, with larger wing nuts. This modification will allow the sled to be adequately secured by
Code of Federal Regulations, 2010 CFR
2010-01-01
... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fasteners. 27.607 Section 27.607 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... bolt, screw, nut, pin, or other fastener whose loss could jeopardize the safe operation of the...
Code of Federal Regulations, 2011 CFR
2011-01-01
... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Fasteners. 27.607 Section 27.607 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS... bolt, screw, nut, pin, or other fastener whose loss could jeopardize the safe operation of the...
Building Tomorrow's Business Today
ERIC Educational Resources Information Center
Ryan, Jim
2010-01-01
Modern automobile maintenance, like most skilled-trades jobs, is more than simple nuts and bolts. Today, skilled-trades jobs might mean hydraulics, computerized monitoring equipment, electronic blueprints, even lasers. As chief executive officer of Grainger, a business-to-business maintenance, repair, and operating supplies company that…
Trends in mechanical fasteners. [considering optimum metric fastener system
NASA Technical Reports Server (NTRS)
Levy, J. B.
1972-01-01
Some of the specialty fasteners which are enjoying increasing usage are: thread rolling screws, self drilling and tapping screws, locking screws, tamperproof fasteners, and flanged bolts and nuts. The development of an optimum metric fastener system is recommended for future fastener manufacturing.
The nuts and bolts of carbon sequestration in forests
The nature of carbon in forests is discussed from the perspective of carbon trading as an incentive for conserving private forest lands. The presentation addresses carbon sequestration in forests and its significance for global warming. Carbon inventories, specifically in the are...
NASA Astrophysics Data System (ADS)
Parvasi, Seyed Mohammad; Ho, Siu Chun Michael; Kong, Qingzhao; Mousavi, Reza; Song, Gangbing
2016-08-01
Bolted joints are ubiquitous structural elements, and form critical connections in mechanical and civil structures. As such, loosened bolted joints may lead to catastrophic failures of these structures, thus inspiring a growing interest in monitoring of bolted joints. A novel energy based wave method is proposed in this study to monitor the axial load of bolted joint connections. In this method, the time reversal technique was used to focus the energy of a piezoelectric (PZT)-generated ultrasound wave from one side of the interface to be measured as a signal peak by another PZT transducer on the other side of the interface. A tightness index (TI) was defined and used to correlate the peak amplitude to the bolt axial load. The TI bypasses the need for more complex signal processing required in other energy-based methods. A coupled, electro-mechanical analysis with elasto-plastic finite element method was used to simulate and analyze the PZT based ultrasonic wave propagation through the interface of two steel plates connected by a single nut and bolt connection. Numerical results, backed by experimental results from testing on a bolted connection between two steel plates, revealed that the peak amplitude of the focused signal increases as the bolt preload (torque level) increases due to the enlarging true contact area of the steel plates. The amplitude of the focused peak saturates and the TI reaches unity as the bolt axial load reaches a threshold value. These conditions are associated with the maximum possible true contact area between the surfaces of the bolted connection.
Device for cutting protrusions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bzorgi, Fariborz M
An apparatus for clipping a protrusion of material is provided. The protrusion may, for example, be a bolt head, a nut, a rivet, a weld bead, or a temporary assembly alignment tab protruding from a substrate surface of assembled components. The apparatus typically includes a cleaver having a cleaving edge and a cutting blade having a cutting edge. Generally, a mounting structure configured to confine the cleaver and the cutting blade and permit a range of relative movement between the cleaving edge and the cutting edge is provided. Also typically included is a power device coupled to the cutting blade.more » The power device is configured to move the cutting edge toward the cleaving edge. In some embodiments the power device is activated by a momentary switch. A retraction device is also generally provided, where the retraction device is configured to move the cutting edge away from the cleaving edge.« less
Survival of biofilm-forming Salmonella on stainless steel bolt threads under dry conditions.
Morita, Yukio; Komoda, Emiko; Ono, Kazuaki; Kumagai, Susumu
2011-01-01
We examined the survival of two biofilm-forming strains and two biofilm-deficient strains of non typhoid Salmonella (NTS) on stainless steel bolt threads under dry conditions. Five µL of tryptone soya broth or egg yolke mulsion containing NTS strains at a concentration of 9 log cfu/mL was dropped onto the thread surfaces of hexagonal bolts. After inoculation, the bolts were screwed into the nuts, and then removed (Separate type) or not removed (Unit type). The two types of samples were kept in a dry environment (20.0-25.0°C, 2-15% humidity) and bacteria on the surfaces were periodically counted. Biofilm-forming strains were recovered from all samples after 336 days of incubation, but biofilm-deficient strains were isolated from only two of 8 samples after 336 days. This finding demonstrates that NTS can survive for approximately one year on bolt threads, providing direct evidence of the potential risk of constructions having crevices or uneven surfaces as possible contamination sources. The risk of cross-contamination may be higher for biofilm-forming strains than for biofilm-deficient strains.
ERIC Educational Resources Information Center
Dessoff, Alan
2011-01-01
The role of a district's technology leader, known by a variety of titles including "chief technology officer" (CTO), "chief information officer" (CIO), "director of technology" and others, is changing rapidly in school systems around the country. These administrators principally have managed the nuts and bolts of…
Remotely operated pipe connector
Josefiak, Leonard J.; Cramer, Charles E.
1988-01-01
An apparatus for remotely assembling and disassembling a Graylock type coctor between a pipe and a closure for the pipe includes a base and a receptacle on the base for the closure. The pipe is moved into position vertically above the closure by a suitable positioning device such that the flange on the pipe is immediately adjacent and concentric with the flange on the closure. A moving device then moves two semicircular collars from a position free of the closure to a position such that the interior cam groove of each collar contacts the two flanges. Finally, a tensioning device automatically allows remote tightening and loosening of a nut and bolt assembly on each side of the collar to cause a seal ring located between the flanges to be compressed and to seal the closure. Release of the pipe and the connector is accomplished in the reverse order. Preferably, the nut and bolt assembly includes an elongate shaft portion on which a removable sleeve is located.
Impact resistance of spar-shell composite fan blades
NASA Technical Reports Server (NTRS)
Graff, J.; Stoltze, L.; Varholak, E. M.
1973-01-01
Composite spar-shell fan blades for a 1.83 meter (6 feet) diameter fan stage were fabricated and tested in a whirling arm facility to evaluate foreign object damage (FOD) resistance. The blades were made by adhesively bonding boron-epoxy shells on titanium spars and then adhesively bonding an Inconel 625 sheath on the leading edge. The rotating blades were individually tested at a tip speed of 800 feet per second. Impacting media used were gravel, rivets, bolt, nut, ice balls, simulated birds, and a real bird. Incidence angles were typical of those which might be experienced by STOL aircraft. The tests showed that blades of the design tested in this program have satisfactory impact resistance to small objects such as gravel, rivets, nuts, bolts, and two inch diameter ice balls. The blades suffered nominal damage when impacted with one-pound birds (9 to 10 ounce slice size). However, the shell was removed from the spar for a larger slice size.
Remotely serviced filter and housing
Ross, Maurice J.; Zaladonis, Larry A.
1988-09-27
A filter system for a hot cell comprises a housing adapted for input of air or other gas to be filtered, flow of the air through a filter element, and exit of filtered air. The housing is tapered at the top to make it easy to insert a filter cartridge using an overhead crane. The filter cartridge holds the filter element while the air or other gas is passed through the filter element. Captive bolts in trunnion nuts are readily operated by electromechanical manipulators operating power wrenches to secure and release the filter cartridge. The filter cartridge is adapted to make it easy to change a filter element by using a master-slave manipulator at a shielded window station.
MACHINING ELIMINATION THROUGH APPLICATION OF THREAD FORMING FASTENERS IN NET SHAPED CAST HOLES
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cleaver, Ryan J; Cleaver, Todd H; Talbott, Richard
The ultimate objective of this work was to eliminate approximately 30% of the machining performed in typical automotive engine and transmission plants by using thread forming fasteners in as-cast holes of aluminum and magnesium cast components. The primary issues at the source of engineers reluctance to implementing thread forming fasteners in lightweight castings are: * Little proof of consistency of clamp load vs. input torque in either aluminum or magnesium castings. * No known data to understand the effect on consistency of clamp load as casting dies wear. The clamp load consistency concern is founded in the fact that amore » portion of the input torque used to create clamp load is also used to create threads. The torque used for thread forming may not be consistent due to variations in casting material, hole size and shape due to tooling wear and process variation (thermal and mechanical). There is little data available to understand the magnitude of this concern or to form the basis of potential solutions if the range of clamp load variation is very high (> +/- 30%). The range of variation that can be expected in as-cast hole size and shape over the full life cycle of a high pressure die casting die was established in previous work completed by Pacific Northwest National Laboratory, (PNNL). This established range of variation was captured in a set of 12 cast bosses by designing core pins at the size and draft angles identified in the sited previous work. The cast bosses were cut into nuts that could be used in the Ford Fastener Laboratory test-cell to measure clamp load when a thread forming fastener was driven into a cast nut. There were two sets of experiments run. First, a series of cast aluminum nuts were made reflecting the range of shape and size variations to be expected over the life cycle of a die casting die. Taptite thread forming fasteners, (a widely used thread forming fastener suitable for aluminum applications), were driven into the various cored, as-cast nuts at a constant input torque and resulting clamp loads were recorded continuously. The clamp load data was used to determine the range of clamp loads to be expected. The bolts were driven to failure. The clamp load corresponding to the target input of 18.5 Nm was recorded for each fastener. In a like fashion, a second set of experiments were run with cast magnesium nuts and ALtracs thread forming fasteners, (a widely used thread forming fastener suitable for magnesium applications). Again all clamp loads were recorded and analyzed similarly to the Taptites in aluminum cast nuts. Results from previous work performed on the same test cell for a Battelle project using standard M8 bolts into standard M8 nuts were included as a comparator for a standard bolt and nut application. The results for the thread forming fasteners in aluminum cast holes were well within industry expectations of +/- 30% for out of the box and robustness range testing. The results for the dry and lubed extreme conditions were only slightly higher than industry expectations at +/- 35.6%. However, when compared to the actual Battelle results (+/- 40%) for a standard bolt and nut the tread forming fasteners performed slightly better. The results for the thread forming fasteners in magnesium cast holes were all well within industry expectations of +/- 30% for all three conditions. The robustness range (.05mm larger and smaller holes than the expected wear pattern of a die casting die at full life cycle) results also fell within the industry expectations for standard threaded fasteners. These results were very encouraging. It was concluded that this work showed that clamp load variation with thread forming fasteners is consistent with industry expectations for standard steel bolts and nuts at +/- 30%. There does not appear to be any significant increase in clamp load variation due to the application of thread forming fasteners in as-cast holes of aluminum or magnesium over the effective life of a die casting mold. The fully implemented potential benefit of thread forming fasteners in as-cast holes of aluminum and magnesium is estimated to be 6 trillion Btu per year for North America. Economic benefit is estimated to be nearly $800 million per year. Environmental benefits and quality improvements will also result from full implementation of this technology.« less
1993-04-29
characteristics such as intuition, telepathy , ESP, PSI, subconscious creativity and the likz. "Don’t do it Ruskey," they told me, "give them nuts and bolts." Nuts...basic shape of the homogeneous media response ( i.e. the primary wave). The synthetic waveforms 72 show good conformance with the field data. The minor...as a fracture halo surrounding the tunnel which is unaccounted for in the simulation. Figure 5 shows a suite of synthetic waveforms for an air tilled
Development of a Laminar Flame Test Facility for Bio-Diesel Characterization
2009-12-01
heat from the fuel injector during operation. NPT Threaded Holes Bolts and Nuts Stainless Steel Pipes 17 Figure 3. Top Flange of the...3 2. Pre- Heat Temperature... Piping Systems........................... 37 2. Leak Test for Combustion Chamber .................................... 38 3. Calibration of High Speed
Use of chemoinformatics tools- nuts and bolts; Challenges in their regulatory application
Cheminformatics spans a continuum of components from data storage to uncovering new insights that are useful for different decision making contexts. It covers the input, retrieval of data, the manipulation and integration of data through to the visualisation and analysis to trans...
Teaching Mathematics to Middle School Students with Learning Difficulties
ERIC Educational Resources Information Center
Montague, Marjorie, Ed.; Jitendra, Asha K., Ed.
2006-01-01
A highly practical resource for special educators and classroom teachers, this book provides specific instructional guidance illustrated with vignettes, examples, and sample lesson plans. Every chapter is grounded in research and addresses the nuts and bolts of teaching math to students who are not adequately prepared for the challenging middle…
Solution-Focused Counseling in Schools, Third Edition
ERIC Educational Resources Information Center
Murphy, John J.
2015-01-01
The third edition of this text covers the philosophical foundations and nuts and bolts of using solution focused counseling to help preschool-12 students resolve problems. Dr. Murphy's practical and respectful approach has been successfully applied throughout the world by school counselors, counselors in training, psychologists, social workers,…
Social and Emotional Learning in the Classroom: Promoting Mental Health and Academic Success
ERIC Educational Resources Information Center
Merrell, Kenneth W.; Gueldner, Barbara A.
2010-01-01
This highly engaging, eminently practical book provides essential resources for implementing social and emotional learning (SEL) in any K-12 setting. Numerous vivid examples illustrate the nuts and bolts of this increasingly influential approach to supporting students' mental health, behavior, and academic performance. Helpful reproducibles are…
Continuity and Change in India’s Foreign Policy: The Next Five Years,
1984-01-01
mainly of food products (tea, coffee, rice, cashews , pepper), tobacco, leather goods, cotton textiles, jute products, light engineering goods, and...industrial fasteners ( nuts and bolts), for example, have drawn strong Indian protests, and the protectionist mood in the United States, as reflected in
Experiencing Organizational Work Design: Beyond Hackman and Oldham
ERIC Educational Resources Information Center
Fornaciari, Charles J.; Dean, Kathy Lund
2005-01-01
Standard organizational behavior survey courses usually introduce students to the "nuts and bolts" of organizational work design and models that mechanize work. This article develops an experiential exercise that simulates working conditions that can foster greater student understanding of the affective, ethical, and human aspects of work design.…
Seasonal Variation in Epidemiology
ERIC Educational Resources Information Center
Marrero, Osvaldo
2013-01-01
Seasonality analyses are important in medical research. If the incidence of a disease shows a seasonal pattern, then an environmental factor must be considered in its etiology. We discuss a method for the simultaneous analysis of seasonal variation in multiple groups. The nuts and bolts are explained using simple trigonometry, an elementary…
Teaching Strategic Processes in Reading. Second Edition
ERIC Educational Resources Information Center
Almasi, Janice F.; Fullerton, Susan King
2012-01-01
This accessible teacher resource and course text shows how to incorporate strategy instruction into the K-8 classroom every day. Cutting-edge theory and research are integrated with practical guidance and reflections from experienced teachers of novice and struggling readers. The book describes the nuts and bolts of creating classroom contexts…
Religion's Return to Higher Education: A Primer
ERIC Educational Resources Information Center
Jacobsen, Douglas; Jacobsen, Rhonda Hustedt
2013-01-01
Board meetings usually focus on nuts-and-bolts issues--action items and financial matters that require immediate discussion and prompt decisions. But larger philosophical issues also sometimes float to the surface--matters having to do with institutional mission, campus ethos, or educational styles--and when these kinds of issues arise, it is…
77 FR 52315 - North Pacific Fishery Management Council; Public Meetings
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-29
... the final rule; Getting the nuts and bolts in place for implementation; Planned outreach and education... version will be posted at http://www.alaskafisheries.noaa.gov/npfmc/ . Although non-emergency issues not... formal action during these meetings. Actions will be restricted to those issues specifically identified...
Effectively Using IEP Goal Banks
ERIC Educational Resources Information Center
Kowalski, Ellen; McCall, Renee; Aiello, Rocco; Lieberman, Lauren
2009-01-01
For students with disabilities, annual goals are the nuts and bolts of the everyday program outlined in their individualized education program (IEP). According to the Individuals with Disabilities Education Improvement Act (IDEA) of 2004, a present level of performance with measurable annual goals must be outlined in a student's IEP. Goals should…
Handbook of Art Therapy. Second Edition
ERIC Educational Resources Information Center
Malchiodi, Cathy A., Ed.
2011-01-01
Providing a complete overview of art therapy, from theory and research to practical applications, this is the definitive handbook in the field. Leading practitioners demonstrate the nuts and bolts of arts-based intervention with children, adults, families, couples, and groups dealing with a wide range of clinical issues. Rich with illustrative…
Ten common errors beginning substance abuse workers make in group treatment.
Greif, G L
1996-01-01
Beginning therapists sometimes make mistakes when working with substance abusers in groups. This article discusses ten common errors that the author has observed. Five center on the therapist's approach and five center on the nuts and bolts of group leadership. Suggestions are offered for how to avoid them.
Mentoring Students with Mild Disabilities: The "Nuts and Bolts" of Program Development.
ERIC Educational Resources Information Center
Campbell-Whatley, Gloria D.
2001-01-01
This article provides step-by-step guidelines for developing a mentoring program for students with disabilities. The benefits of mentoring, role of the mentor, mentor screening, and program development are discussed. Suggested mentor and student activities are outlined, including communication, reading, leisure, and academic activities. (Contains…
NASA Technical Reports Server (NTRS)
Bradley, Glen L.
1993-01-01
Wrench ends pivot so it can be used to loosen or tighten nuts or bolts in confined spaces. One end equipped with open-end socket; other end, with double-hexagon socket. Heads pivot on pins. Pins fit tightly so heads do not flop; friction on pins sufficient to hold heads in positions until rotated intentionally.
Bearing Surface Pressure Distribution of Nut with Cone-form Bearing Surface
NASA Astrophysics Data System (ADS)
Okada, Manabu; Kasei, Shinji
Recently, wheel separation accidents in such vehicles as trucks, buses and passenger cars have drawn a social concern. Explications of their causes and adequate practices of countermeasures for them have been urgently required. In relation to this issue, the authors have taken notice of subjects which are concerned in bolted joints at wheels and are especially trying to study the pressure distribution at the bearing surface of nuts. This report deals with the subject of a nut with a cone-form bearing surface. Considerations are based on numerical results derived from finite-element-analysis. Feature of the pressure distribution by this profile and influences from geometrical deviations of the form are mainly discussed, and some other information concerning this issue is presented.
Wosar, Marc A; Marcellin-Little, Denis J; Roe, Simon C
2002-01-01
To evaluate the effects of bolt torque, wire size, and component reuse on the ability to maintain wire tension in 3 external skeletal fixation systems. Biomechanical study. Yield strength in tension of 1.0-, 1.2-, 1.5-, and 1.6-mm-diameter wires, and yield strength in torque of Hofmann Small Bone Fixation (SBF) cannulated and slotted bolts and IMEX regular and miniature bolts were determined on a testing machine. The minimum bolt tightening torque needed to prevent wire slippage at clinically recommended wire tensions was determined. Components were tested 10 times, and loads at slippage were recorded. The IMEX system required a mean of 8 Nm of bolt tightening torque to maintain 900 N (1.6-mm wires). The SBF system required a mean of 3 Nm bolt torque to maintain 300 N (1.0-mm wires) and 5 Nm to maintain 600 N (1.2-mm wires). The SBF cannulated bolt required 9 Nm of torque to maintain 900 N (1.5-mm wires). The SBF slotted bolts could only maintain 800 N before yield. The IMEX miniature system required a mean bolt torque of 1.1 Nm to maintain 300 N. The cannulated and slotted bolts from both manufacturers failed to maintain 70% of initial wire tension after 7 and 4 uses, respectively. The IMEX systems and the SBF system using 1.0- and 1.2-mm wires could maintain clinically recommended wire tension safely. Only the IMEX system could maintain clinically recommended wire tension safely using 1.5- or 1.6-mm wires. The SBF system using 1.0- and 1.2-mm wires and the IMEX system using all wire sizes can maintain clinically relevant wire tension. The SBF system using 1.5-mm wires could not. Cannulated and slotted bolts should not be used more than 6 and 3 times, respectively. Nuts should not be reused. Copyright 2002 by The American College of Veterinary Surgeons
The High Energy Universe: Ultra-High Energy Events in Astrophysics and Cosmology
NASA Astrophysics Data System (ADS)
Mészáros, Péter
2010-09-01
1. Introduction; 2. The nuts and bolts of the Universe; 3. Cosmology; 4. Cosmic structure formation; 5. Active galaxies; 6. Stellar cataclysms; 7. Gamma ray bursts; 8. GeV and TeV gamma rays; 9. Gravitational waves; 10. Cosmic rays; 11. Neutrinos; 12. Dark dreams, Higgs and beyond.
Price, D.
1958-09-01
An improved means is described for removably installing and supporting a collector pocket in a calutron. The salient feature of the invention is the support of the collector pocket by means of suspension bolts engaging the pocket at a point intermediate the top and bottom of the pocket, and having nuts so arranged that by turing the desired predetermined position.
How to Influence the IDEA Regulations
ERIC Educational Resources Information Center
Dale, Richard E.
2011-01-01
Teachers of children with disabilities know how greatly the Individuals With Disabilities Education Act (IDEA) regulations influence their daily practices; and they no doubt have strong opinions about regulations that go too far or not far enough to allow them to help their students succeed. This article offers practical, nuts-and-bolts help for…
(Pea)nuts and Bolts of Visual Narrative: Structure and Meaning in Sequential Image Comprehension
ERIC Educational Resources Information Center
Cohn, Neil; Paczynski, Martin; Jackendoff, Ray; Holcomb, Phillip J.; Kuperberg, Gina R.
2012-01-01
Just as syntax differentiates coherent sentences from scrambled word strings, the comprehension of sequential images must also use a cognitive system to distinguish coherent narrative sequences from random strings of images. We conducted experiments analogous to two classic studies of language processing to examine the contributions of narrative…
Designing and Developing Programs for Gifted Students.
ERIC Educational Resources Information Center
Smutny, Joan Franklin, Ed.
The 13 readings in this book offer guidelines for designing and developing programs for gifted students. An introductory chapter by the editor considers the benefits of special programs for gifted students and the challenges of their development. The following chapters are: (1) "From Needs and Goals to Program Organization: A Nuts-and-Bolts Guide"…
ERIC Educational Resources Information Center
Cash, Terry; Duttweiler, Patricia Cloud
2006-01-01
This truancy prevention publication provides a general background discussion on the issue of truancy but mainly centers on the nuts and bolts of developing and implementing an effective community wide collaborative to address truancy. The first section provides some understanding of the factors associated with truancy and the resulting high costs…
49 CFR 180.509 - Requirements for inspection and test of specification tank cars.
Code of Federal Regulations, 2012 CFR
2012-10-01
... tank car owner can determine by analysis (e.g., finite element analysis, damage-tolerance analysis, or... missing or loose bolts, nuts, or elements that may make the tank car unsafe for transportation; (5) An... must ensure the structural elements on the tank car qualify with the applicable requirements of this...
49 CFR 180.509 - Requirements for inspection and test of specification tank cars.
Code of Federal Regulations, 2013 CFR
2013-10-01
... tank car owner can determine by analysis (e.g., finite element analysis, damage-tolerance analysis, or... missing or loose bolts, nuts, or elements that may make the tank car unsafe for transportation; (5) An... must ensure the structural elements on the tank car qualify with the applicable requirements of this...
49 CFR 180.509 - Requirements for inspection and test of specification tank cars.
Code of Federal Regulations, 2014 CFR
2014-10-01
... tank car owner can determine by analysis (e.g., finite element analysis, damage-tolerance analysis, or... missing or loose bolts, nuts, or elements that may make the tank car unsafe for transportation; (5) An... must ensure the structural elements on the tank car qualify with the applicable requirements of this...
ERIC Educational Resources Information Center
deLisle, Lee
2009-01-01
"Creating Special Events" is organized as a systematic approach to festivals and events for students who seek a career in event management. This book looks at the evolution and history of festivals and events and proceeds to the nuts and bolts of event management. The book presents event management as the means of planning, organizing, directing,…
Statistics and Data Interpretation for Social Work
ERIC Educational Resources Information Center
Rosenthal, James A.
2011-01-01
Written by a social worker for social work students, this is a nuts and bolts guide to statistics that presents complex calculations and concepts in clear, easy-to-understand language. It includes numerous examples, data sets, and issues that students will encounter in social work practice. The first section introduces basic concepts and terms to…
Unit: Model for Matter, Inspection Pack, National Trial Print.
ERIC Educational Resources Information Center
Australian Science Education Project, Toorak, Victoria.
Mental and physical models are treated in the Australian Science Education Project trial unit prepared for students in a transitional stage between concrete and abstract reasoning. Students are introduced to the particle model of matter through a series of core activities, including a combination game using nuts and bolts, culminating in a…
The Key for Holding a Successful ELT Conference: Some Nuts and Bolts
ERIC Educational Resources Information Center
Sadeghi, Karim; Modirkhameneh, Sima
2013-01-01
Conferences are gatherings that attract attendants from various places and serve both academic and social purposes. Organizing an international conference is, accordingly, a very challenging, demanding and time-consuming task. In order for the conference organizers to hold a successful conference, there is a need for a comprehensive guide to use…
District CIO: Not Your Mother's Student Information System
ERIC Educational Resources Information Center
Finkel, Ed
2012-01-01
Like seemingly everyone else connected to K12 education, vendors that offer student information systems are being called upon to do more with less. Where past generations of these systems focused on nuts and bolts such as time, attendance and behavioral issues, the latest generation has created--and drawn inspiration from--districts' desires for…
Homework Help from the Library: In Person and Online
ERIC Educational Resources Information Center
Intner, Carol F.
2011-01-01
Children's and young adult librarians are crucial links to effective learning for students. This straightforward handbook is filled with nuts-and-bolts advice on the best ways to help young people with their homework, no matter what the assignment. Carol F. Intner, a certified English teacher and experienced tutor, concentrates on the practical,…
Building Type Basics for College and University Facilities. Building Type Basics.
ERIC Educational Resources Information Center
Neuman, David J.; Kliment, Stephen A.
This book provides indepth information that is needed to initiate a variety of building projects on a diverse range of college and university campuses. Filled with project photographs, diagrams, floor plans, sections, and details, the book combines highly illustrative, specialized material from industry leaders with nuts-and-bolts design…
Mayers, Pat; Alperstein, Melanie; Duncan, Madeleine; Olckers, Lorna; Gibbs, Trevor
2006-03-01
Multi-professional education has traditionally aimed to develop health professionals who are able to collaborate effectively in comprehensive healthcare delivery. The respective professions learn about their differences in order to work together, rather than developing unity in their commitment to a shared vision of professionalism and service. In this, the second of two papers, the 'nuts and bolts' or practicalities of designing a transformed curriculum for a multi-professional course with a difference is described. Guidelines for the curriculum design process, which seeks to be innovative, grounded in theory and relevant to the learning of the students and the ultimately the health of the patients, include: valuing education; gaining buy-in; securing buy-out; defining of roles; seeking consensus; negotiating difference and expediting decisions. The phases of the design process are described, as well as the educational outcomes envisaged during the process. Reflections of the designers, in particular on what it means to be a multi-professional team, and a reconceptualization of multi-professional education are presented as challenges for educators of health professionals.
Structural Analysis of the Redesigned Ice/Frost Ramp Bracket
NASA Technical Reports Server (NTRS)
Phillips, D. R.; Dawicke, D. S.; Gentz, S. J.; Roberts, P. W.; Raju, I. S.
2007-01-01
This paper describes the interim structural analysis of a redesigned Ice/Frost Ramp bracket for the Space Shuttle External Tank (ET). The proposed redesigned bracket consists of mounts for attachment to the ET wall, supports for the electronic/instrument cables and propellant repressurization lines that run along the ET, an upper plate, a lower plate, and complex bolted connections. The eight nominal bolted connections are considered critical in the summarized structural analysis. Each bolted connection contains a bolt, a nut, four washers, and a non-metallic spacer and block that are designed for thermal insulation. A three-dimensional (3D) finite element model of the bracket is developed using solid 10-node tetrahedral elements. The loading provided by the ET Project is used in the analysis. Because of the complexities associated with accurately modeling the bolted connections in the bracket, the analysis is performed using a global/local analysis procedure. The finite element analysis of the bracket identifies one of the eight bolted connections as having high stress concentrations. A local area of the bracket surrounding this bolted connection is extracted from the global model and used as a local model. Within the local model, the various components of the bolted connection are refined, and contact is introduced along the appropriate interfaces determined by the analysts. The deformations from the global model are applied as boundary conditions to the local model. The results from the global/local analysis show that while the stresses in the bolts are well within yield, the spacers fail due to compression. The primary objective of the interim structural analysis is to show concept viability for static thermal testing. The proposed design concept would undergo continued design optimization to address the identified analytical assumptions and concept shortcomings, assuming successful thermal testing.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Barley, C.D.; Winn, C.B.
1997-12-31
This paper provides an overview of the emerging technology of remote, stand-alone electrical power systems featuring a renewable source (wind or photovoltaics [PV]) as well as a diesel generator, with or without an energy storage device. Other stand-alone power systems are discussed briefly, mainly to emphasize the domain of hybrid systems. The history of hybrid systems is reviewed, beginning with the first wind/diesel system in the late 1970s. Other topics include issues arising from the characteristics of diesel engine/generator sets; simple vs. complex systems; the various energy storage technologies that have been used or proposed; control strategies; modeling; optimization; andmore » some {open_quotes}nuts & bolts{close_quotes} details. The bibliography includes over 130 references which are cited throughout the topical discussions. It is concluded that the technical feasibility of hybrid systems has been demonstrated through many prototype installations, and that areas for further improvements include higher reliability and more economical energy storage devices. 139 refs., 7 figs., 1 tab.« less
ERIC Educational Resources Information Center
Sundet, Marit
2016-01-01
This article seeks to present an original and distinct contribution to the literature on internationalisation of Higher Education, by focusing on the very mundane processes through which agreement is reached on the nuts and bolts of the enactment of "internationalisation," and the nature of "internationalisation" as an…
Handbook of Parenting. Volume 5: Practical Issues in Parenting. Second Edition.
ERIC Educational Resources Information Center
Bornstein, Marc H., Ed.
Concerned with practical aspects of meeting children's needs, this volume, the fifth of five on parenting, describes the nuts and bolts of parenting as well as the promotion of positive parenting practices. The volume consists of the following 19 chapters: (1) "The Ethics of Parenting" (Diana Baumrind and Ross A. Thompson; (2) "Parenting and…
FlagHouse Forum: Ability Switches--The Nuts and Bolts
ERIC Educational Resources Information Center
Exceptional Parent, 2011
2011-01-01
An ability switch, in simple terms, is an alternative to a button that requires fine dexterity to push. Many toys and appliances operate because of fine motor stimulation, prohibiting many people with fine motor challenges from finding independence with daily tasks. Ability switches offer the option to make things work with a simple gesture that…
Cleanup Verification Package for the 600-47 Waste Site
DOE Office of Scientific and Technical Information (OSTI.GOV)
M. J. Cutlip
This cleanup verification package documents completion of interim remedial action for the 600-47 waste site. This site consisted of several areas of surface debris and contamination near the banks of the Columbia River across from Johnson Island. Contaminated material identified in field surveys included four areas of soil, wood, nuts, bolts, and other metal debris.
Remedial Education at Community Colleges in the State University of New York
ERIC Educational Resources Information Center
Romano, Richard M.
2011-01-01
Although much has been written about remedial education, little has actually been published on the "nuts and bolts" of its campus operation. This study helps fill in that information gap. Its main purpose is to provide a descriptive inventory of the policies and procedures found in one of the largest community college systems in the…
ERIC Educational Resources Information Center
Franko, Debra L.
2016-01-01
In this paper, I report the development of a mentoring program in a College of Health Sciences comprised of schools of nursing, pharmacy, and health professions (which include physical therapy, speech pathology and audiology, applied psychology, and physician assistant programs) at a large private university. Although university-wide mentoring…
Stock room, just off the large first floor machine ship. ...
Stock room, just off the large first floor machine ship. Here were stored various cutting edges and drill bits used on the machines. Some raw materials were stored here as well, along with nuts and bolts, machine screws, etc. - Thomas A. Edison Laboratories, Building No. 5, Main Street & Lakeside Avenue, West Orange, Essex County, NJ
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-01
... torque spanner to the specifications in the torque figures shown in Table 2. of the Accomplishment... torque check of the tension bolts. Related investigative actions include: Inspecting the condition of the... of the nut being tightened to the end of the thread. Examining the wear pattern on the seating...
Sonnets, High Tech, Haiku: Teaching Poetry in the CAI Classroom.
ERIC Educational Resources Information Center
Krebs, Cynthia; Nichols, Chloe
This report emphasizes the techniques required today for effective slide construction and contains suggestions about the nuts and bolts of slide preparation. Two instructors developed a presentation at Utah Valley State College to enhance their teaching of the sonnet and the Japanese haiku. Their premise: since poetry is a highly visual art form,…
76 FR 423 - Airworthiness Directives; Fokker Services B.V. Model F.28 Mark 0100 Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2011-01-05
... dog-links was found broken (one on the nut side & one on the head side). In both occasions, the bolt... affected. If a single dog-link connection fails, the complete stabilizer load is taken up by the remaining dog-link connection. * * * To address and correct this unsafe condition EASA [European Aviation Safety...
75 FR 43876 - Airworthiness Directives; Fokker Services B.V. Model F.28 Mark 0100 Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-27
... aeroplanes, one of the bolts that connect the horizontal stabilizer control unit actuator with the dog-links... single dog-link connection fails, the complete stabilizer load is taken up by the remaining dog-link... the horizontal stabilizer control unit actuator with the dog-links was found broken (one on the nut...
Using Media Advocacy to Promote Detention Reform: A Practice Guide to Juvenile Detention Reform
ERIC Educational Resources Information Center
Annie E. Casey Foundation, 2009
2009-01-01
Written specifically for juvenile justice advocates and officials, this handbook provides step-by-step media approaches to promote the system reforms achieved through the Juvenile Detention Alternatives Initiative (JDAI). Those interested in learning all the nuts and bolts of media advocacy may choose to read this guide from cover to cover. Others…
Community Colleges and the State Budget: The Nuts and Bolts.
ERIC Educational Resources Information Center
Lay, Scott
2003-01-01
This article provides insight into the California state budget process and gives an overview of California's growing deficit. The author examines the decline in personal income gained from stock options and capital gains as a means of illustrating the economic factors that resulted in a $28 billion deficit. Next, the author turns his attention to…
An analysis of pipe flange connections using epoxy adhesives/anaerobic sealant instead of gaskets
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sawa, T.; Sasaki, R.; Yoneno, M.
1995-11-01
This paper deals with the strength and the sealing performance of pipe flange connections combining the bonding force of adhesives with the clamping force of bolts. The epoxy adhesives or anaerobic sealants are bonded at the interface partially instead of gaskets in pipe flange connections. The stress distribution in the epoxy adhesives (anaerobic sealant), which governs the sealing performance, and the variations in axial bolt force are analyzed, using an axisymmetrical theory of elasticity, when an internal pressure is applied to a connection in which two pipe flanges are clamped together buy bolts and nuts with an initial clamping forcemore » after being joined by epoxy adhesives or anaerobic sealant. In addition, a method for estimating the strength of the combination connection is demonstrated. Experiments are performed and the analytical results are consistent with the experimental results concerning the variation in axial bolt force and the strength of combination connections. It can be seen that the strength of connections increases with a decrease in the bolt pitch circle diameter. Furthermore, it is seen that the sealing performance of such combination connections in which the interface is bonded partially is improved over that of pipe flange connections with metallic gaskets.« less
Finite element analysis of the Space Shuttle 2.5-inch frangible nut
NASA Technical Reports Server (NTRS)
McKinnis, Darin N.
1994-01-01
Finite element analysis of the Space Shuttle 2.5-inch frangible nut was conducted to improve understanding of the current design and proposed design changes to this explosively-actuated nut. The 2.5-inch frangible nut is used in two places to attach the aft end of the Space Shuttle Orbiter to the External Tank. Both 2.5-inch frangible nuts must function to complete safe separation. The 2.5-inch frangible nut contains two explosive boosters containing RDX explosive each capable of splitting the nut in half, on command from the Orbiter computers. To ensure separation, the boosters are designed to be redundant. The detonation of one booster is sufficient to split the nut in half. However, beginning in 1987 some production lots of 2.5-inch frangible nuts have demonstrated an inability to separate using only a single booster. The cause of the failure has been attributed to differences in the material properties and response of the Inconel 718 from which the 2.5-inch frangible nut is manufactured. Subsequent tests have resulted in design modifications of the boosters and frangible nut. Model development and initial analysis was conducted by Sandia National Laboratories (SNL) under funding from NASA Lyndon B. Johnson Space Center (NASA-JSC) starting in 1992. Modeling codes previously developed by SNL were transferred to NASA-JSC for further analysis on this and other devices. An explosive bolt with NASA Standard Detonator (NSD) charge, a 3/4-inch frangible nut, and the Super*Zip linear separation system are being modeled by NASA-JSC.
Aerospace Threaded Fastener Strength in Combined Shear and Tension Loading
NASA Technical Reports Server (NTRS)
Steeve, B. E.; Wingate, R. J.
2012-01-01
A test program was initiated by Marshall Space Flight Center and sponsored by the NASA Engineering and Safety Center to characterize the failure behavior of a typical high-strength aerospace threaded fastener under a range of shear to tension loading ratios for both a nut and an insert configuration where the shear plane passes through the body and threads, respectively. The testing was performed with a customized test fixture designed to test a bolt with a single shear plane at a discrete range of loading angles. The results provide data to compare against existing combined loading failure criteria and to quantify the bolt strength when the shear plane passes through the threads.
Vibration Monitoring of Power Distribution Poles
DOE Office of Scientific and Technical Information (OSTI.GOV)
Clark Scott; Gail Heath; John Svoboda
2006-04-01
Some of the most visible and least monitored elements of our national security infrastructure are the poles and towers used for the distribution of our nation’s electrical power. Issues surrounding these elements within the United States include safety such as unauthorized climbing and access, vandalism such as nut/bolt removal or destructive small arms fire, and major vandalism such as the downing of power poles and towers by the cutting of the poles with a chainsaw or torches. The Idaho National Laboratory (INL) has an ongoing research program working to develop inexpensive and sensitive sensor platforms for the monitoring and characterizationmore » of damage to the power distribution infrastructure. This presentation covers the results from the instrumentation of a variety of power poles and wires with geophone assemblies and the recording of vibration data when power poles were subjected to a variety of stimuli. Initial results indicate that, for the majority of attacks against power poles, the resulting signal can be seen not only on the targeted pole but on sensors several poles away in the distribution network and a distributed sensor system can be used to monitor remote and critical structures.« less
27 CFR 555.209 - Construction of type 3 magazines.
Code of Federal Regulations, 2010 CFR
2010-04-01
... Construction of type 3 magazines. A type 3 magazine is a “day-box” or other portable magazine. It must be fire...-type hardboard. Doors must overlap sides by at least one inch. Hinges and hasps are to be attached by welding, riveting or bolting (nuts on inside). One steel padlock (which need not be protected by a steel...
27 CFR 555.209 - Construction of type 3 magazines.
Code of Federal Regulations, 2014 CFR
2014-04-01
... Construction of type 3 magazines. A type 3 magazine is a “day-box” or other portable magazine. It must be fire...-type hardboard. Doors must overlap sides by at least one inch. Hinges and hasps are to be attached by welding, riveting or bolting (nuts on inside). One steel padlock (which need not be protected by a steel...
ERIC Educational Resources Information Center
Strike, Kimberly T.
2006-01-01
This CD provides a thorough approach to the nuts and bolts of information that is needed by new faculty and staff. The disc allows administrators or personnel charged with the job of orientation of new staff, a quick and easy template that will provide a thorough orientation to a new building and or district.
49 CFR 571.209 - Standard No. 209; Seat belt assemblies.
Code of Federal Regulations, 2011 CFR
2011-10-01
... anchorage nuts, plates, or washers, need not have such hardware, but shall have 7/16-20 UNF-2A or 1/2-13UNC... plates or washers furnished for universal floor, installations shall be of steel, free from burrs and... 2580 mm2 in projected area. The distance between any edge of the plate and the edge of the bolt hole...
School Boards and the Ballot Box. How To Win Elections for Your Schools and for Yourself.
ERIC Educational Resources Information Center
Etheredge, Forest D.
All aspects of school elections ranging from the nuts and bolts of campaign organization and media relations to effective long-term strategies to sustain community support for school funding and board member leadership comprise the 11 chapters of this two-part book. The first part offers an overview of board member election campaigns and effective…
Fixture for environmental exposure of structural materials under compression load
NASA Technical Reports Server (NTRS)
Clark, R. K.; Lisagor, W. B. (Inventor)
1983-01-01
A device for stressing a deformable material specimen consists of top plate and a bottom plate sandwiching a guide cylinder. The specimen is positioned on the bottom plate and attached to a load piston. Force is applied through the top plate into the guide cylinder. Once the specimen is loaded, the stress is maintained by tightening tie bolt nuts.
Structural aspects of cold-formed steel section designed as U-shape composite beam
NASA Astrophysics Data System (ADS)
Saggaff, Anis; Tahir, Mahmood Md.; Azimi, Mohammadamin; Alhajri, T. M.
2017-11-01
Composite beam construction usually associated with old-style Hot-Rolled Steel Section (HRSS) has proven to act much better in compare with Cold-Formed Steel Section (CFSS) sections due to thicker section. Due, it's getting popular to replace HRSS with CFSS in some aspects as a composite beam. The advantages such as lightweight, cost effective and easy to install have contributed to the apply CFSS as a preferred construction material for composite beam. There is a few technical data available regarding the application of the usage of CFSS as a composite system, despite the potentials use for residential and light-weight industrial constructions. This paper presents an experimental tests results which have been conducted using CFSS as composite beam. Composite action of CFSS arranged as double beam with Self-Compacting Concrete (SCC) slab are integrated together with bolted shear connectors were used. A full-scale test comprised of 3 proposed composite beam specimens with bolted shear connector spaced at 300 mm interval of grade 8.8 was using single nut with washer on flange of CFS, cast to the slab and loaded until failed. The test show that the bolted shear connector yielded better capacity of ultimate strength and ultimate moment for the proposed composite beam. It can be concluded that, bolted shear connectors of 16 mm in diameter performed better than the other diameter size of bolted shear connectors.
The research on delayed fracture behavior of high-strength bolts in steel structure
NASA Astrophysics Data System (ADS)
Li, Guo dong; Li, Nan
2017-07-01
High-strength bolts have been widely used in power plants. However, the high-strength bolts which being employed in pumping station, steel structure and pipeline anti-whip structure have been found delayed fracture for many times in a power plant, this will affect the reliability of steel fracture and bring blow risk caused by falling objects. The high-strength bolt with delayed fracture was carried out fracture analysis, metallurgical analysis, chemical analysis, mechanical analysis, as well as bolts installation analysis, it can be comprehensively confirmed that the direct cause of high-strength bolts delayed fracture is the stress corrosion, and the root cause of high-strength bolts delayed fracture should be the improper installation at the initial and the imperfect routine anti-corrosion maintenance.
ERIC Educational Resources Information Center
Bullock, Bob; And Others
This minicourse was prepared for use with secondary physics students in the Dallas Independent School District and is one option in a physics program which provides for the selection of topics on the basis of student career needs and interests. This minicourse was aimed at two levels in the study of basic machines. The "light" level…
ERIC Educational Resources Information Center
Kerrigan, Seanna M.
2015-01-01
More than four thousand students engage in the community-based learning capstone program every year by enrolling in one of 240 senior-level courses that culminate their undergraduate education. In this article, the author shares the context and history of the program, its foundational principles and processes, and the nuts-and-bolts details of the…
Trouble-Free Transitions for Teachers: 3 CDs for Public Elementary, Middle, and High Schools [CD-ROM
ERIC Educational Resources Information Center
Strike, Kimberly T.
2006-01-01
These CDs provide a thorough approach to the nuts and bolts of information that is needed by new faculty and staff. The discs allow administrators or personnel charged with the job of orientation of new staff a quick and easy template that will provide a thorough orientation to a new building and or district. For personnel directors, principals,…
ERIC Educational Resources Information Center
Gary, Juneau M.; Remolino, Linda
Online support groups provide an alternative vehicle of support for people in distress by linking people who have similar problems. They have the potential to improve the access and delivery of support to a wide range of people, including some who would not seek face-to-face support at all. Online support groups reduce the sense of isolation…
ERIC Educational Resources Information Center
Marmolejo-Ramos, Fernando; Cousineau, Denis
2017-01-01
The number of articles showing dissatisfaction with the null hypothesis statistical testing (NHST) framework has been progressively increasing over the years. Alternatives to NHST have been proposed and the Bayesian approach seems to have achieved the highest amount of visibility. In this last part of the special issue, a few alternative…
Environmental regulations: Technical reference manual TRM 016.01, September 15, 1995
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1995-09-15
This TRM is divided into two primary sections. The first section entitled Environmental Programs provides a synopsis of each environmental Act (Federal Law). The second section of the TRM is entitled Environmental Operations. This section is in effect the nuts and bolts of the regulatory compliance programs. In this section, the program manager can reference specific requirements which will aid in structuring the compliance program.
ERIC Educational Resources Information Center
Pace, Diana; Witucki, Laurie; Blumreich, Kathleen
2008-01-01
This paper describes the rationale and the step by step process for setting up a WISE (Women in Science and Engineering) learning community at one institution. Background information on challenges for women in science and engineering and the benefits of a learning community for female students in these major areas are described. Authors discuss…
A Nuts and Bolts Guide to College Success for Students Who Are Deaf or Hard of Hearing
ERIC Educational Resources Information Center
PEPNet 2, 2012
2012-01-01
Beginning your college education means you'll be exploring a new place, making new friends, learning new things and setting your own priorities. You are going to face a lot of big changes in a short time. That's exciting--and challenging. The more prepared you are for college when you get there, the more ready you'll be to address these new…
NASA Technical Reports Server (NTRS)
Hart, J. F.
1973-01-01
MSFC-STD-486, Threaded Fasteners, Torque Limits For, is a relatively new standard that has not had much user experience. This test was run to provide such experience and verify the values in MSFC-STD-486. This was accomplished by plotting torque-tension curves on aluminum and alloy steel aircraft quality bolts and nuts through 1/2 inch in diameter.
Threaded average temperature thermocouple
NASA Technical Reports Server (NTRS)
Ward, Stanley W. (Inventor)
1990-01-01
A threaded average temperature thermocouple 11 is provided to measure the average temperature of a test situs of a test material 30. A ceramic insulator rod 15 with two parallel holes 17 and 18 through the length thereof is securely fitted in a cylinder 16, which is bored along the longitudinal axis of symmetry of threaded bolt 12. Threaded bolt 12 is composed of material having thermal properties similar to those of test material 30. Leads of a thermocouple wire 20 leading from a remotely situated temperature sensing device 35 are each fed through one of the holes 17 or 18, secured at head end 13 of ceramic insulator rod 15, and exit at tip end 14. Each lead of thermocouple wire 20 is bent into and secured in an opposite radial groove 25 in tip end 14 of threaded bolt 12. Resulting threaded average temperature thermocouple 11 is ready to be inserted into cylindrical receptacle 32. The tip end 14 of the threaded average temperature thermocouple 11 is in intimate contact with receptacle 32. A jam nut 36 secures the threaded average temperature thermocouple 11 to test material 30.
Results of tests of MTA-2 TPS on the SRB hold-down bolt blast container
NASA Technical Reports Server (NTRS)
Dean, W. G.
1982-01-01
The four solid rocket booster (SRB) hold-down posts are fastened to the mobile launch platform (MLP) with four large nuts. At liftoff the nuts are split with explosive changes to release the SRB/Shuttle. A blast container is placed over the nuts to protect the vehicle from flying debris. The blast container is a reusable part and has to be protected from aerodynamic heating during flight. The thermal protection system (TPS) used to protect these blast containers is cork. Fitting the flat cork sheet to this hemispherical shaped blast container is both time consuming and expensive. Another problem is removing the charred cork and epoxy glue from the blast containers. Replacements of this cork with another TPS material such as MTA-2 was examined. Heating rates along the centerline of the forward facing areas of the blast container were determined. The feasibility of using 1/2 in. MTA-2 on the SRB blast containers for protection from ascent, plume impingement and reentry heating is demonstrated.
USSR Report, Military Affairs.
1987-03-04
ordering, it is recom- mended that the JPRS number, title, date and author , if applicable, of publication be cited. Current JPRS publications are...useful. Advise me, what more can I do?" It is difficult to read such letters and also not easy to answer them. The editors are not authorized to...claims of their authors . They propose anything: from a perpetual motion motor to bolts with a round nut. Another aspect to which we should not close
Daly, Rich
2011-11-21
Providers say the administration's growing emphasis on billing audits is pushing them to the limit and threatens to increase their costs. Many billing problems stem from simple errors, not fraud, they say. "When you get into the nuts and bolts of some of these programs you realize it's not as easy as taking the overpayment line out of the budget," says Michael Regier, of VHA.
Design and Verification of Space Station EVA-Operated Truss Attachment System
NASA Technical Reports Server (NTRS)
Katell, Gabriel
2001-01-01
This paper describes the design and verification of a system used to attach two segments of the International Space Station (ISS). This system was first used in space to mate the P6 and Z1 trusses together in December 2000, through a combination of robotic and extravehicular tasks. Features that provided capture, coarse alignment, and fine alignment during the berthing process are described. Attachment of this high value hardware was critical to the ISS's sequential assembly, necessitating the inclusion of backup design and operational features. Astronauts checked for the proper performance of the alignment and bolting features during on-orbit operations. During berthing, the system accommodates truss-to-truss relative displacements that are caused by manufacturing tolerances and on-orbit thermal gradients. After bolt installation, the truss interface becomes statically determinate with respect to in-plane shear loads and isolates attach bolts from bending moments. The approach used to estimate relative displacements and the means of accommodating them is explained. Confidence in system performance was achieved through a cost-effective collection of tests and analyses, including thermal, structural, vibration, misalignment, contact dynamics, underwater simulation, and full-scale functional testing. Design considerations that have potential application to other mechanisms include accommodating variations of friction coefficients in the on-orbit joints, wrench torque tolerances, joint preload, moving element clearances at temperature extremes, and bolt-nut torque reaction.
Pyrotechnic shock at the orbiter/external tank forward attachment
NASA Technical Reports Server (NTRS)
Rogers, W. F.; Grissom, D. S.; Rhodes, L. R.
1980-01-01
During the initial certification test of the forward structural attachment of the space shuttle orbiter to the external tank, pyrotechnic shock from actuation of the separation device resulted in structural failure of the thermal protection tiles surrounding the attachment. Because of the high shock associated with the separation bolt, the development of alternative low shock separation designs was initiated. Two concepts that incorporate a 5.08 centimeter frangible nut as the release device were developed and tested.
Nuts and Bolts of the Ion Band State Theory
NASA Astrophysics Data System (ADS)
Chubb, Scott R.
2005-12-01
The nuts and bolts of our ion band state theory of low energy nuclear reactions (LENR's) in palladium-deuteride (PdD) and palladium-hydride (PdH) are the electrons that hold together or tear apart the bonds (or lack of bonds) between deuterons (d's) or protons (p's) and the host material. In PdDx and PdHx, this bonding is strongly correlated with loading. In ambient loading conditions (x ≲ 0.6), bonding inhibits ion band state occupation. As x → 1, slight increases and decreases in loading can induce "vibrations" (which have conventionally been thought to occur from phonons) that can induce potential losses or increases of p/d. Naive assumptions about phonons fail to include these losses and increases. These effects can occur because neither H or D has core electrons and because in either PdD or PdH, the electrons near the Fermi energy have negligible overlap with the nucleus of either D or H. In the past, implicitly, we have used these facts to justify our ion band state theory. Here, we present a more formal justification, based on the relationship between H(D) ion band states (IBS's) and H(D) phonons that includes a microscopic picture that explains why occupation of IBS's can occur in PdD and PdH and how this can lead to nuclear reactions.
Design and Demonstration of Bolt Retractor Separation System for X-38 Deorbit Propulsion Stage
NASA Technical Reports Server (NTRS)
Ahmed, Raf; Johnston, A. S.; Garrison, J. C.; Gaines, J. L.; Waggoner, J. D.
2003-01-01
A separation system was designed for the X-38 experimental crew return vehicle program to allow the Deorbit Propulsion Stage (DPS) to separate from the X-38 lifting body during reentry operations. The configuration chosen was a spring-loaded plunger, known as the Bolt Retractor Subsystem (BRS), that retracts each of the six DPS-to-lifting body attachment bolts across the interface plane after being triggered by a separation nut mechanism. The system was designed to function on the ground in an atmospheric environment as well as in space. The BRS provides the same functionality as that of a completely pyrotechnic shear separation system that would normally be considered ideal for this application, but at a much lower cost. This system also could potentially be applied to future space station crew return vehicles. The design goal of 40 ms retraction time was successfully met in a series of demonstrations performed at the NASA Marshall Space Flight Center s Pyrotechnic Shock Facility (PSF) and Flight Robotics Laboratory (FRL). It must be emphasized that a full-scale test series was not performed on the BRS due to program schedule and cost constraints.
Design Considerations for Abrasive Blast Rooms and Recovery Systems
2010-02-01
COLUMN BOLT – ALLOWS FOR WIDER ENCLOSURES – STRONG ENOUGH TO SUPPORT MONORAIL Flange Bolt Room Column Bolt Room • Structural steel framework...OVERHEAD MONORAILS • EXTERIOR WORK STATIONS • TURNTABLES • HORIZONTAL ROTATION DEVICES OVERHEAD MONORAIL Workpiece Handling • Powered horizontal rotation
Performance and Long Duration Test of a 30 kw Thermal Arcjet Engine.
1987-11-01
Surface ____________________________ 69 50. SEM Close-up of Cathode Crater Surface Completely Covered with Arc Microspots and Splashed Tung- sten ...gaskets, and possibly stretching the bolts and/or nuts. 17 CL 4- C4 ---- 40 as 00 CiC E 18~ le J .Ir e 5 Figure 11 is a composite picture of the... composition . This transducer was zeroed both electronically and with reference to an ion gauge in a second vacuum system pumped by 26 F6 W. 320 a 280- (n, gis
Methods of Measuring Stress Relaxation in Composite Tape Springs
2015-03-26
plate in order to spread the load evenly and prevent excess torque . The plate also allows for force on the tape spring to be applied to the entire...aluminum squares that can be tightened to the base. The test fixture is secured to the marble base. The tape springs are folded in three locations with...top plate is pressed down by tightening the bolt on each nut. The tightening is complete when the tape spring just begins to create an M shape and
2008-11-01
103 2.3.6 Use of Model 4 for MANPRINT Evaluation of the M1A2 in the IOTE ..........103 iv 3. Conclusions...System (ASAS) Block II Initial Operational Test and Evaluation ( IOTE ) 203 Appendix I. Noise and Temperature Measurements in and Around the HETS...Test and Evaluation (LUTE), Initial Operational Test and Evaluation ( IOTE ) or a Follow-on Test and Evaluation (FOTE)—was being planned, our Field
Testing of Compact Bolted Fasteners with Insulation and Friction-Enhanced Shims for NCSX
DOE Office of Scientific and Technical Information (OSTI.GOV)
L. E. Dudek, J.H. Chrzanowski, G. Gettelfinger, P. Heitzenroeder, S. Jurczynski, M. Viola and K. Freudenberg
The fastening of the National Compact Stellarator Experiment's (NCSX) modular coils presented a number of engineering and manufacturing challenges due to the high magnetic forces, need to control induced currents, tight tolerances and restrictive space envelope. A fastening method using high strength studs, jack nuts, insulating spacers, bushings and alumina coated shims was developed which met the requirements. A test program was conducted to verify the design. The tests included measurements of flatness of the spacers, determination of contact area, torque vs. tension of the studs and jack nuts, friction coefficient tests on the alumina and G-10 insulators, electrical tests,more » and tension relaxation tests due to temperature excursions from room temperature to liquid nitrogen temperatures. This paper will describe the design and the results of the test program.« less
NASA Astrophysics Data System (ADS)
Skrzypkowski, Krzysztof; Korzeniowski, Waldemar; Zagórski, Krzysztof; Dudek, Piotr
2017-09-01
In the underground mines of the Legnica-Głogów Copper District (LGOM) the main way to protect the room excavation is the use of a rock bolt support. For many years, it has proven to be an efficient security measure in excavations which met all safety standards and requirements. The article presents the consumption of the rock bolt support in the Mining Department "Polkowice-Sieroszowice" in the years 2010-2015 as well as the number of bolt supports that were used to secure the excavations. In addition, it shows the percentage of bolt supports that were used to conduct rebuilding work and cover the surface of exposed roofs. One of the factors contributing to the loss of the functionality of bolt supports is corrosion whose occurrence may lead directly to a reduction in the diameter of rock bolt support parts, in particular rods, bearing plates and nuts. The phenomenon of the corrosion of the bolt support and its elements in underground mining is an extremely common phenomenon due to the favorable conditions for its development in mines, namely high temperature and humidity, as well as the presence of highly aggressive water. This involves primarily a decrease in the capacity of bolt support construction, which entails the need for its strengthening, and often the need to perform the reconstruction of the excavation. The article presents an alternative for steel bearing plates, namely plates made using the spatial 3D printing technology. Prototype bearing plates were printed on a 3D printer Formiga P100 using the "Precymit" material. The used printing technology was SLS (Selective Laser Sintering), which is one of the most widely used technologies among all the methods of 3D printing for the short series production of the technical parts of the final product. The article presents the stress-strain characteristic of the long expansion connected rock bolt support OB25 with a length of 3.65 m. A rock bolt support longer than 2.6 m is an additional bolt support in excavations, and it is increasingly frequently used to reinforce roofs and in rebuilding the underground mines of KGHM Polish Copper S.A. In order to conduct the laboratory tests that are most suitable for the mine conditions, and yet are carried out on a laboratory test facility, the Authors used a steel cylinder with an external diameter of 102 mm and a length of 600 mm, which was filled with a core of rock (dolomite) from the roofs of the mine workings. In addition the maximum load that took over the bolt support made of rods and connected with sleeves was determined. For the initial tension, the elastic and plastic range of the maximal displacements, which were measured by the rope encoder, were determined. The statical tests of the expansion rock bolt support were carried out at the laboratory of the Department of Underground Mining in simulated mine conditions. The test facility enables the study of the long bolt rods on a geometric scale of 1:1 for the different ways of fixing. The aim of the laboratory research was to obtain the stress-strain characteristics, of the long expansion rock bolt support with a steel bearing plate and a plate printed on a 3D printer.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tomizawa, Shinya
We show a uniqueness theorem for Kaluza-Klein black holes in the bosonic sector of five-dimensional minimal supergravity. More precisely, under the assumptions of the existence of two commuting axial isometries and a nondegenerate connected event horizon of the cross-section topology S{sup 3}, or lens space, we prove that a stationary charged rotating Kaluza-Klein black hole in five-dimensional minimal supergravity is uniquely characterized by its mass, two independent angular momenta, electric charge, magnetic flux, and nut charge, provided that there exists neither a nut nor a bolt (a bubble) in the domain of outer communication. We also show that under themore » assumptions of the same symmetry, same asymptotics, and the horizon cross section of S{sup 1}xS{sup 2}, a black ring within the same theory--if it exists--is uniquely determined by its dipole charge and rod intervals besides the charges and magnetic flux.« less
High-Precision Coupling Mechanism Operable By Robots
NASA Technical Reports Server (NTRS)
Voellmer, George
1992-01-01
Coupling mechanism has features making it easily operable by hand and suitable for operation by robots: tolerates some initial misalignment, imposes precise final alignment, and protects itself against overtightening. Typically used to mount equipment module on structure. Mechanism includes kinematic mounts, which tolerate small initial misalignment and enforce precise final alignment as two assemblies brought together. Clamping force applied to kinematic mounts via two flexible plates. Bolt and nut tightened on flexible plates to impose spring clamping load. Repeatability of interface tested and found to be better than forty-millionths of inch.
Solving nuts-and-bolts nuclear problems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Olmstead, A.; Schoen, J.
1979-05-01
The Operations and Maintenance Information Service (MIS), created and operated by NUS Corp., was designed to improve plant availability through the exchange of practical information between nuclear plants and a return to an emphasis on the problem-solving process. MIS meetings cover a range of plant problems and have been unique in bringing the rapid feedback of information pertinent to the day-to-day working operation of a total plant. Much of the response is by telephone contact, although the monthly newsletter, semi-annual meetings, and scheduled plant visits are also helpful.
Efficient Bayesian mixed model analysis increases association power in large cohorts
Loh, Po-Ru; Tucker, George; Bulik-Sullivan, Brendan K; Vilhjálmsson, Bjarni J; Finucane, Hilary K; Salem, Rany M; Chasman, Daniel I; Ridker, Paul M; Neale, Benjamin M; Berger, Bonnie; Patterson, Nick; Price, Alkes L
2014-01-01
Linear mixed models are a powerful statistical tool for identifying genetic associations and avoiding confounding. However, existing methods are computationally intractable in large cohorts, and may not optimize power. All existing methods require time cost O(MN2) (where N = #samples and M = #SNPs) and implicitly assume an infinitesimal genetic architecture in which effect sizes are normally distributed, which can limit power. Here, we present a far more efficient mixed model association method, BOLT-LMM, which requires only a small number of O(MN)-time iterations and increases power by modeling more realistic, non-infinitesimal genetic architectures via a Bayesian mixture prior on marker effect sizes. We applied BOLT-LMM to nine quantitative traits in 23,294 samples from the Women’s Genome Health Study (WGHS) and observed significant increases in power, consistent with simulations. Theory and simulations show that the boost in power increases with cohort size, making BOLT-LMM appealing for GWAS in large cohorts. PMID:25642633
Post-Service Examination of PWR Baffle Bolts, Part I. Examination and Test Plan
DOE Office of Scientific and Technical Information (OSTI.GOV)
Leonard, Keith J.; Sokolov, Mikhail A.; Gussev, Maxim N.
2015-04-30
In support of extended service and current operations of the US nuclear reactor plants, the Oak Ridge National Laboratory (ORNL), through the Department of Energy (DOE), Light Water Reactor Sustainability (LWRS) Program, is coordinating with Ginna Nuclear Power Plant, The Westinghouse Electric Company, LLC, and ATI Consulting, the selective procurement of baffle bolts that were withdrawn from service in 2011 and currently stored on site at Ginna. The goal of this program is to perform detailed microstructural and mechanical property characterization of baffle former bolts following in-service exposures. This report outlines the selection criteria of the bolts and the techniquesmore » to be used in this study. The bolts available are the original alloy 347 steel fasteners used in holding the baffle plates to the baffle former structures within the lower portion of the pressurized water reactor vessel. Of the eleven possible bolts made available for this work, none were identified to have specific damage. The bolts, however, did show varying levels of breakaway torque required in their removal. The bolts available for this study varied in peak fluence (highest dose within the head of the bolt) between 9.9 and 27.8x10 21 n/cm 2 (E>1MeV). As no evidence for crack initiation was determined for the available bolts from preliminary visual examination, two bolts with the higher fluence values were selected for further post-irradiation examination. The two bolts showed different breakaway torque levels necessary in their removal. The information from these bolts will be integral to the LWRS program initiatives in evaluating end of life microstructure and properties. Furthermore, valuable data will be obtained that can be incorporated into model predictions of long-term irradiation behavior and compared to results obtained in high flux experimental reactor conditions. The two bolts selected for the ORNL study will be shipped to Westinghouse with bolts of interest to their collaborative efforts with the Electric Power Research Institute. Westinghouse will section the ORNL bolts into samples specified in this report and return them to ORNL. Samples will include bend bars for fracture toughness and crack propagation studies along with thin sections from which specimens for bend testing, subscale tensile and microstructural analysis can be obtained. Additional material from the high stress concentration region at the transition between the bolt head and shank will also be preserved to allow for further investigation of possible crack initiation sites.« less
Evaluation of high-strength Cu-Ni-Mn-Al bolting used in oil and gas service
DOE Office of Scientific and Technical Information (OSTI.GOV)
Andersen, O.; Joosten, M.W.; Murali, J.
1996-08-01
High strength bolts, nuts, studs and screws manufactured from a precipitation hardening Cu-Ni-Mn-Al alloy have experienced several failures in recent years in oilfield installations with varying degrees of severity and consequence. Such failures have been broadly attributed to Stress Corrosion Cracking (SCC) and Liquid Metal Embrittlement (LME) phenomena. A detailed test program using the Slow Strain Rate Testing (SSRT) method has been conducted to identify the various parameters which could contribute to SCC. Results indicate that the Cu-Ni-Mn-Al alloy is susceptible to SCC in a variety of environments commonly found in oilfield equipment manufacturing and field installations such as amine-containingmore » additives, sulfides and even natural seawater at elevated temperatures. SSRT testing indicated, however, that, in seawater environments, low service temperatures and cathodic protection did not adversely affect the alloy`s performance. Discussion of test program results and qualitative correlations with field failures are presented.« less
Top 10 Steps to Business Success
NASA Astrophysics Data System (ADS)
Arnold, Gianna
2013-03-01
What does it really take to build a successful technology based company? This fast paced and interactive discussion will highlite potential missteps as well as actions that increase the likelihood of success. Topics under consideration will include: how to begin, creating an organizational structure, creating a plan, selecting a name, financing, allocating resources as efficiently as possible, building a team, protecting intangible assets, strategic alliances, obtaining revenue and transitioning from startup to growth. The primary goal of this presentation is to help you identify value-creating practices as well as wasteful practices, while providing the general nuts and bolts required to move forward.
Approximations first: a closer look at applications of the definite integral
NASA Astrophysics Data System (ADS)
Brandt, Keith
2017-01-01
I propose that students pay more attention to the approximations that lead to integral formulas when they study applications of the definite integral. The goal is to focus students on the underlying concepts and the definition of the definite integral - and to steer them away from memorizing formulas. To address this goal, I have written some computer-based activities that guide students through the nuts and bolts of the approximations that eventually lead to integral formulas. I describe the activities and suggest a few changes as to how we might approach this material.
Energy Neutral Wireless Bolt for Safety Critical Fastening
Seyoum, Biruk B.
2017-01-01
Thermoelectric generators (TEGs) are now capable of powering the abundant low power electronics from very small (just a few degrees Celsius) temperature gradients. This factor along with the continuously lowering cost and size of TEGs, has contributed to the growing number of miniaturized battery-free sensor modules powered by TEGs. In this article, we present the design of an ambient-powered wireless bolt for high-end electro-mechanical systems. The bolt is equipped with a temperature sensor and a low power RF chip powered from a TEG. A DC-DC converter interfacing the TEG with the RF chip is used to step-up the low TEG voltage. The work includes the characterizations of different TEGs and DC-DC converters to determine the optimal design based on the amount of power that can be generated from a TEG under different loads and at temperature gradients typical of industrial environments. A prototype system was implemented and the power consumption of this system under different conditions was also measured. Results demonstrate that the power generated by the TEG at very low temperature gradients is sufficient to guarantee continuous wireless monitoring of the critical fasteners in critical systems such as avionics, motorsport and aerospace. PMID:28954432
Energy Neutral Wireless Bolt for Safety Critical Fastening.
Seyoum, Biruk B; Rossi, Maurizio; Brunelli, Davide
2017-09-26
Thermoelectric generators (TEGs) are now capable of powering the abundant low power electronics from very small (just a few degrees Celsius) temperature gradients. This factor along with the continuously lowering cost and size of TEGs, has contributed to the growing number of miniaturized battery-free sensor modules powered by TEGs. In this article, we present the design of an ambient-powered wireless bolt for high-end electro-mechanical systems. The bolt is equipped with a temperature sensor and a low power RF chip powered from a TEG. A DC-DC converter interfacing the TEG with the RF chip is used to step-up the low TEG voltage. The work includes the characterizations of different TEGs and DC-DC converters to determine the optimal design based on the amount of power that can be generated from a TEG under different loads and at temperature gradients typical of industrial environments. A prototype system was implemented and the power consumption of this system under different conditions was also measured. Results demonstrate that the power generated by the TEG at very low temperature gradients is sufficient to guarantee continuous wireless monitoring of the critical fasteners in critical systems such as avionics, motorsport and aerospace.
A guide to FERC regulation and ratemaking of electric utilites and other power suppliers
DOE Office of Scientific and Technical Information (OSTI.GOV)
Small, M.E.
1994-12-31
This book is very useful for its thorough survey of issues and cases pertinent to electric utility rate filings at the Federal Energy Regulatory Commission (FERC). As the author states, the book provides a step-by-step analysis of the statutory provisions, regulations and case law that are pertinent to the establishment of electric utility sales and transmission rates. The book takes a nuts and bolts approach to the examination of the ratemaking process for electric utilities. Three chapters cover in detail cost of service, rate of return, functionalization, classification and allocation, and rate design, issues which are at the heart ofmore » traditional cost of service ratemaking. Other chapters explain Title II of the Federal POwer Act and general rate filing procedures. Chapters 7 and 8 address the fuel adjustment clause and price squeeze, respectively. Chapters 9, 10, and 11 largely cover new developments in FERC policies since the previous edition of the book was published in 1989, including market based rates, QF certification issues and transmission issues. This volume is useful to the neophyte to electric utility regulation because of its comprehensiveness in addressing ratemaking issues. Also, it is useful to the seasoned practitioner because of its identification of pertinent case law.« less
Martin, Miriam S; Kline, Helen C; Wagner, Dana R; Alexander, Lacey R; Edwards-Callaway, Lily N; Grandin, Temple
2018-05-03
The objective of this study was to assess the effects of captive bolt length and breed type on post-stun leg activity in cattle. A total of 2850 Holstein (HOL) and non-Holstein British/Continental bred (NHOL) steers and heifers were observed post-stunning at a large commercial slaughter facility. A pneumatically powered penetrating captive bolt stunner was used with three different bolt lengths: CON, 15.24 cm; MED, 16.51 cm; and LON, 17.78 cm. Hind limb kicking, forelimb activity, take away belt stops, carcass swing and number of knife sticks during exsanguination were recorded for each animal from video recording. Hind limb and forelimb kicks observed ranged from 0 to 25 and 0 to 8, respectively. Analysis of post-stun hind limb and forelimb activity indicated that increasing pneumatically powered penetrating captive bolt length does not decrease post-stun leg activity. There was a higher percentage of cattle experiencing take away belt stops and carcass swing in HOL as compared with NHOL. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.
Optimum design of bolted composite lap joints under mechanical and thermal loading
NASA Astrophysics Data System (ADS)
Kradinov, Vladimir Yurievich
A new approach is developed for the analysis and design of mechanically fastened composite lap joints under mechanical and thermal loading. Based on the combined complex potential and variational formulation, the solution method satisfies the equilibrium equations exactly while the boundary conditions are satisfied by minimizing the total potential. This approach is capable of modeling finite laminate planform dimensions, uniform and variable laminate thickness, laminate lay-up, interaction among bolts, bolt torque, bolt flexibility, bolt size, bolt-hole clearance and interference, insert dimensions and insert material properties. Comparing to the finite element analysis, the robustness of the method does not decrease when modeling the interaction of many bolts; also, the method is more suitable for parametric study and design optimization. The Genetic Algorithm (GA), a powerful optimization technique for multiple extrema functions in multiple dimensions search spaces, is applied in conjunction with the complex potential and variational formulation to achieve optimum designs of bolted composite lap joints. The objective of the optimization is to acquire such a design that ensures the highest strength of the joint. The fitness function for the GA optimization is based on the average stress failure criterion predicting net-section, shear-out, and bearing failure modes in bolted lap joints. The criterion accounts for the stress distribution in the thickness direction at the bolt location by applying an approach utilizing a beam on an elastic foundation formulation.
A Method to Capture Macroslip at Bolted Interfaces [PowerPoint
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hopkins, Ronald Neil; Heitman, Lili Anne Akin
2016-01-01
Relative motion at bolted connections can occur for large shock loads as the internal shear force in the bolted connection overcomes the frictional resistive force. This macroslip in a structure dissipates energy and reduces the response of the components above the bolted connection. There is a need to be able to capture macroslip behavior in a structural dynamics model. A linear model and many nonlinear models are not able to predict marcoslip effectively. The proposed method to capture macroslip is to use the multi-body dynamics code ADAMS to model joints with 3-D contact at the bolted interfaces. This model includesmore » both static and dynamic friction. The joints are preloaded and the pinning effect when a bolt shank impacts a through hole inside diameter is captured. Substructure representations of the components are included to account for component flexibility and dynamics. This method was applied to a simplified model of an aerospace structure and validation experiments were performed to test the adequacy of the method.« less
NASA Astrophysics Data System (ADS)
Lin, Shan
2018-04-01
There have been lots of reports about the occurrence of cracks in bolts in aging nuclear and thermal power plants. Sizing of such cracks is crucial for assessing the integrity of bolts. Currently, hammering and visual tests are used to detect cracks in bolts. However, they are not applicable for sizing cracks. Although the tip diffraction method is well known as a crack sizing technique, reflection echoes from threads make it difficult to apply this technique to bolts. This paper addresses a method for depth sizing of cracks in bolts by means of ultrasonic phased array technology. Numerical results of wave propagation in bolts by the finite element method (FEM) shows that a peak associated within the vicinity of a crack tip can be observed in the curve of echo intensity versus refraction angle for deep cracks. The refraction angle with respect to this peak decreases as crack depth increases. Such numerical results are verified by experiments on bolt specimens that have electrical discharge machining notches or fatigue cracks with different depths. In the experiment, a 10-MHz linear array probe is used. Depth of cracks in bolts using the refraction angle associated with the peak is determined and compared to actual depths. The comparison shows that accurately determining a crack depth from the inspection results is possible.
The nuts and bolts of evaluating science communication activities.
Spicer, Suzanne
2017-10-01
Since 2008 there has been a focus on fostering a culture of public engagement in higher education plus an impact agenda that demands scientists provide evidence of how their work, including their science communication, is making a difference. Good science communication takes a significant amount of time to plan and deliver so how can you improve what you are doing and demonstrate if you are having an impact? The answer is to evaluate. Effective evaluation needs to be planned so this paper takes you step by step through the evaluation process, illustrated using specific examples. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.
Berger-Fiffy, Jill
2012-01-01
Harvard Vanguard Medical Associates (Harvard Vanguard) decided to develop a Shared Medical Appointment (SMA) program in 2007 for a variety of reasons. The program has launched 86 SMAs in 17 specialties at 12 sites and has exceeded 13 000 patient visits. Currently, the practice offers 54 SMAs and is believed to be the largest program in the country. This article provides an overview regarding staffing, space and equipment, project planning, promotional materials, training programs, workflow development, and the use of quality improvement (ie, LEAN) tools used to monitor the work to be completed and the metrics to date.
Predicting SPE Fluxes: Coupled Simulations and Analysis Tools
NASA Astrophysics Data System (ADS)
Gorby, M.; Schwadron, N.; Linker, J.; Caplan, R. M.; Wijaya, J.; Downs, C.; Lionello, R.
2017-12-01
Presented here is a nuts-and-bolts look at the coupled framework of Predictive Science Inc's Magnetohydrodynamics Around a Sphere (MAS) code and the Energetic Particle Radiation Environment Module (EPREM). MAS simulated coronal mass ejection output from a variety of events can be selected as the MHD input to EPREM and a variety of parameters can be set to run against: bakground seed particle spectra, mean free path, perpendicular diffusion efficiency, etc.. A standard set of visualizations are produced as well as a library of analysis tools for deeper inquiries. All steps will be covered end-to-end as well as the framework's user interface and availability.
Carmichael, H.
1952-11-11
The manufacture of electrode insulators that are mechanically strong, shock-proof, vacuum tight, and are capable of withstanding gas pressures of many atmospheres under intense neutron bombardment, such as may be needed in an ionization chamber, is described. The ansulator comprises a bolt within a quartz tube, surrounded by a bushing held in place by two quartz rings, and tightened to a pressure of 1,000 pounds per square inch by a nut and washer. Quartz is the superior material to meet these conditions, however, to withstand this pressure the quartz must be fire polished, lapped to form smooth and parallel surfaces, and again fire polished to form an extremely smooth and fracture resistant mating surface.
Monolithic Flexure Pre-Stressed Ultrasonic Horns
NASA Technical Reports Server (NTRS)
Sherrit, Stewart; Bao, Xiaoqi; Badescu, Mircea; Bar-Cohen, Yoseph; Allen, Phillip Grant
2011-01-01
High-power ultrasonic actuators are generally assembled with a horn, backing, stress bolt, piezoelectric rings, and electrodes. The manufacturing process is complex, expensive, difficult, and time-consuming. The internal stress bolt needs to be insulated and presents a potential internal discharge point, which can decrease actuator life. Also, the introduction of a center hole for the bolt causes many failures, reducing the throughput of the manufactured actuators. A new design has been developed for producing ultrasonic horn actuators. This design consists of using flexures rather than stress bolts, allowing one to apply pre-load to the piezoelectric material. It also allows one to manufacture them from a single material/plate, rapid prototype them, or make an array in a plate or 3D structure. The actuator is easily assembled, and application of pre-stress greater than 25 MPa was demonstrated. The horn consists of external flexures that eliminate the need for the conventional stress bolt internal to the piezoelectric, and reduces the related complexity. The stress bolts are required in existing horns to provide prestress on piezoelectric stacks when driven at high power levels. In addition, the manufacturing process benefits from the amenability to produce horn structures with internal cavities. The removal of the pre-stress bolt removes a potential internal electric discharge point in the actuator. In addition, it significantly reduces the chances of mechanical failure in the piezoelectric stacks that result from the hole surface in conventional piezoelectric actuators. The novel features of this disclosure are: 1. A design that can be manufactured from a single piece of metal using EDM, precision machining, or rapid prototyping. 2. Increased electromechanical coupling of the horn actuator. 3. Higher energy density. 4. A monolithic structure of a horn that consists of an external flexure or flexures that can be used to pre-stress a solid piezoelectric structure rather than a bolt, which requires a through hole in the piezoelectric material. 5. A flexure system with low stiffness that accommodates mechanical creep with minor reduction in pre-stress.
Thermal conductance measurements of bolted copper joints for SuperCDMS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schmitt, R.; Tatkowski, Greg; Ruschman, M.
2015-09-01
Joint thermal conductance testing has been undertaken for bolted copper to copper connections from 60 mK to 26 K. This testing was performed to validate an initial design basis for the SuperCDMS experiment, where a dilution refrigerator will be coupled to a cryostat via multiple bolted connections. Copper used during testing was either gold plated or passivated with citric acid to prevent surface oxidation. Results obtained are well fit by a power law regression of joint thermal conductance to temperature and match well with data collected during a literature review.
NASA Astrophysics Data System (ADS)
Matetic, Rudy J.
Over-exposure to noise remains a widespread and serious health hazard in the U.S. mining industries despite 25 years of regulation. Every day, 80% of the nation's miners go to work in an environment where the time weighted average (TWA) noise level exceeds 85 dBA and more than 25% of the miners are exposed to a TWA noise level that exceeds 90 dBA, the permissible exposure limit (PEL). Additionally, MSHA coal noise sample data collected from 2000 to 2002 show that 65% of the equipment whose operators exceeded 100% noise dosage comprise only seven different types of machines; auger miners, bulldozers, continuous miners, front end loaders, roof bolters, shuttle cars (electric), and trucks. In addition, the MSHA data indicate that the roof bolter is third among all the equipment and second among equipment in underground coal whose operators exceed 100% dosage. A research program was implemented to: (1) determine, characterize and to measure sound power levels radiated by a roof bolting machine during differing drilling configurations (thrust, rotational speed, penetration rate, etc.) and utilizing differing types of drilling methods in high compressive strength rock media (>20,000 psi). The research approach characterized the sound power level results from laboratory testing and provided the mining industry with empirical data relative to utilizing differing noise control technologies (drilling configurations and types of drilling methods) in reducing sound power level emissions on a roof bolting machine; (2) distinguish and correlate the empirical data into one, statistically valid, equation, in which, provided the mining industry with a tool to predict overall sound power levels of a roof bolting machine given any type of drilling configuration and drilling method utilized in industry; (3) provided the mining industry with several approaches to predict or determine sound pressure levels in an underground coal mine utilizing laboratory test results from a roof bolting machine and (4) described a method for determining an operators' noise dosage of a roof bolting machine utilizing predicted or determined sound pressure levels.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Al-Odwani, A.; Carew, J.; Al-Hashem, A.
1999-11-01
The crevice corrosion tests were performed on UNS S31603, UNS S31703, UNS S31726, UNS S31254, UNS N08904, UNS N625, UNS N825 and UNS N276 was investigated in seawater and neutral brine solution using a multiple crevice washer assembly. PTFE multiple-crevice washers were bolted to both sides of the test specimens with PTFE bolts and nuts. The specimens were exposed to seawater flowing at a rate of 100 L/h for periods of 3,000 h and 6,000 h. Duplicate specimens were immersed in a plexiglass cell containing the flowing seawater at a temperature of 30 C. The results showed that all themore » tested coupons were susceptible to some degree of crevice corrosion attack. However, the stainless steels were the most severely affected. The degree of crevice corrosion attack for the nickel base alloys decreased as the percentage of molybdenum content in the alloys increased. Destruction of the passive layer by the concentration of chloride or acidity and reduction of hydrogen ions at the crevices is believed to be the cause of the crevice attack.« less
Thermal conductance measurements of bolted copper joints for SuperCDMS
Schmitt, R. L.; Tatkowski, G.; Ruschman, M.; ...
2015-04-28
Joint thermal conductance testing has been undertaken for bolted copper to copper connections from 60 mK to 26 K. This testing was performed to validate an initial design basis for the SuperCDMS experiment, where a dilution refrigerator will be coupled to a cryostat via multiple bolted connections. Copper used during testing was either gold plated or passivated with citric acid to prevent surface oxidation. Finally, the results we obtained are well fit by a power law regression of joint thermal conductance to temperature and match well with data collected during a literature review.
NASA Task Load Index (TLX). Volume 1.0; Paper and Pencil Package
NASA Technical Reports Server (NTRS)
Hart, Sandra G.
1986-01-01
This booklet contains the materials necessary to collect subjective workload assessments with the NASA Task Load Index. This procedure for collecting workload ratings was developed by the Human Performance Group at NASA Ames Research Center during a three year research effort that involved more than 40 laboratory. simulation. and inflight experiments. Although the technique is still undergoing evaluation. this booklet is being distributed to allow other researchers to use it in their own experiments. Comments or suggestions about the procedure would be greatly appreciated. This package is intended to fill a "nuts and bolts" function of describing the procedure. A bibliography provides background information about previous empirical findings and the logic that supports the procedure.
Implementing the chemical weapons convention: The nuts and bolts of compliance
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tanzman, E.A.
This paper is a presentation prepared for the American Bar Association in which the author discusses the issue of rights to privacy in the United States in the face of implementing the Chemical Weapons Convention inspections. The author points out that there are no clear precedents in law which deal with all the issues which will result from international inspections for verification which are required by the treaty. In particular as inspections tread on the issue of personal rights or private property there is a fairly ill defined legal area which needs to be developed to allow such inspections inmore » the face of constitutional guarantees.« less
Tool For Driving Many Fasteners Simultaneously
NASA Technical Reports Server (NTRS)
Cook, Joseph S., Jr.
1995-01-01
Proposed tool tightens or loosens several bolts, screws, nuts, or other threaded fasteners arranged in circle on compressor head, automotive wheel, pipe-end flange, or similar object. Enables assembly or disassembly in fraction of time needed to tighten fasteners one at a time. Simultaneously applies same torque to all fasteners, preventing distortion and enhancing reliability. Concept not limited to circular fastener patterns. Adapted to rectangular configurations like on engine intake manifolds, by adding gears to drive train to provide proper spacing. Designed to deliver fixed or adjustable maximum torque. To ensure even seal loading, piston pressure simultaneously ramped from initial to final values to maintain relatively constant torque loading on all fasteners until final specifications limit achieved.
Standard Engineering Installation Package, Standard Remote Terminals (SRT).
1981-10-30
6L L o 0 100 BOLT // M 0 (NOTE 3) N o @ 12 P o 13 NOTE: USE MiTN SAAD-D-4053 AND 0 14 • STD-SD-00SS DWS. 1I USE 3(4 CONDUIT AND BOX CONN. PUNCH OUT 3/4...TERMINAL STRIP. USE # BOLT TO MOUNT CONNECTOR TO DLII. USE OG STD-SO-007 FOR TERMINAL STRIP TERMINA- TION TO 153 PATCH PANEL. *1 f DUS1 is not or’dered... BOLTED TO FLOOR AS PER DUG 3I ®STu-SD-OO69 PROVIDING THERE IS INO CROSS OVLR WITH POWER AND SIGNAL CABLES. CROSSOVER WILL BE SEPERATED BY 4" MINIMUM
Alignment positioning mechanism
NASA Technical Reports Server (NTRS)
Fantasia, Peter M. (Inventor)
1991-01-01
An alignment positioning mechanism for correcting and compensating for misalignment of structures to be coupled is disclosed. The mechanism comprises a power screw with a base portion and a threaded shank portion. A mounting fixture is provided for rigidly coupling said base portion to the mounting interface of a supporting structure with the axis of the screw perpendicular thereto. A traveling ball nut threaded on the power screw is formed with an external annular arcuate surface configured in the form of a spherical segment and enclosed by a ball nut housing with a conforming arcuate surface for permitting gimballed motion thereon. The ball nut housing is provided with a mounting surface which is positionable in cooperable engagement with the mounting interface of a primary structure to be coupled to the supporting structure. Cooperative means are provided on the ball nut and ball nut housing, respectively, for positioning the ball nut and ball nut housing in relative gimballed position within a predetermined range of relative angular relationship whereby severe structural stresses due to unequal loadings and undesirable bending moments on the mechanism are avoided.
Non-destructive testing of full-length bonded rock bolts based on HHT signal analysis
NASA Astrophysics Data System (ADS)
Shi, Z. M.; Liu, L.; Peng, M.; Liu, C. C.; Tao, F. J.; Liu, C. S.
2018-04-01
Full-length bonded rock bolts are commonly used in mining, tunneling and slope engineering because of their simple design and resistance to corrosion. However, the length of a rock bolt and grouting quality do not often meet the required design standards in practice because of the concealment and complexity of bolt construction. Non-destructive testing is preferred when testing a rock bolt's quality because of the convenience, low cost and wide detection range. In this paper, a signal analysis method for the non-destructive sound wave testing of full-length bonded rock bolts is presented, which is based on the Hilbert-Huang transform (HHT). First, we introduce the HHT analysis method to calculate the bolt length and identify defect locations based on sound wave reflection test signals, which includes decomposing the test signal via empirical mode decomposition (EMD), selecting the intrinsic mode functions (IMF) using the Pearson Correlation Index (PCI) and calculating the instantaneous phase and frequency via the Hilbert transform (HT). Second, six model tests are conducted using different grouting defects and bolt protruding lengths to verify the effectiveness of the HHT analysis method. Lastly, the influence of the bolt protruding length on the test signal, identification of multiple reflections from defects, bolt end and protruding end, and mode mixing from EMD are discussed. The HHT analysis method can identify the bolt length and grouting defect locations from signals that contain noise at multiple reflected interfaces. The reflection from the long protruding end creates an irregular test signal with many frequency peaks on the spectrum. The reflections from defects barely change the original signal because they are low energy, which cannot be adequately resolved using existing methods. The HHT analysis method can identify reflections from the long protruding end of the bolt and multiple reflections from grouting defects based on mutations in the instantaneous frequency, which makes weak reflections more noticeable. The mode mixing phenomenon is observed in several tests, but this does not markedly affect the identification results due to the simple medium in bolt tests. The mode mixing can be reduced by ensemble EMD (EEMD) or complete ensemble EMD with adaptive noise (CEEMDAN), which are powerful tools to used analyze the test signal in a complex medium and may play an important role in future studies. The HHT bolt signal analysis method is a self-adaptive and automatic process, which can be programed as analysis software and will make bolt tests more convenient in practice.
Submillimeter bolt location in car bodywork for production line quality inspection
NASA Astrophysics Data System (ADS)
Altamirano-Robles, Leopoldo; Arias-Estrada, Miguel; Alviso-Quibrera, Samuel; Lopez-Lopez, Aurelio
2000-03-01
In the automotive industry, a vehicle begins with the construction of the vehicle floor. Later on, several robots weld a series of bolts to this floor which are used to fix other parts. Due to several problems, like welding tools wearing, robot miscalibration or momentary low power supply, among others, some bolts are incorrectly positioned or are not present at all, bringing problems and delays in the next work cells. Therefore, it is of importance to verify the quality of welded parts before the following assembly steps. A computer vision system is proposed in order to locate autonomously the presence and quality of the bolts. The system should carry on the inspection in real time at the car assembly line under the following conditions: without touching the bodywork, with a precision in the submillimeter range and in few seconds. In this paper we present a basic computer vision system for bolt location in the submillimeter range. We analyze three arrangements of the system components (camera and illumination sources) that produce different results in the localization. Results are presented and compared for the three approaches obtained under laboratory conditions. The algorithms were tested in the assembling line. Variations up to one millimeter in the welded position of the bolts were observed.
The Nuts and Bolts of Transcriptionally Silent Chromatin in Saccharomyces cerevisiae
Gartenberg, Marc R.; Smith, Jeffrey S.
2016-01-01
Transcriptional silencing in Saccharomyces cerevisiae occurs at several genomic sites including the silent mating-type loci, telomeres, and the ribosomal DNA (rDNA) tandem array. Epigenetic silencing at each of these domains is characterized by the absence of nearly all histone modifications, including most prominently the lack of histone H4 lysine 16 acetylation. In all cases, silencing requires Sir2, a highly-conserved NAD+-dependent histone deacetylase. At locations other than the rDNA, silencing also requires additional Sir proteins, Sir1, Sir3, and Sir4 that together form a repressive heterochromatin-like structure termed silent chromatin. The mechanisms of silent chromatin establishment, maintenance, and inheritance have been investigated extensively over the last 25 years, and these studies have revealed numerous paradigms for transcriptional repression, chromatin organization, and epigenetic gene regulation. Studies of Sir2-dependent silencing at the rDNA have also contributed to understanding the mechanisms for maintaining the stability of repetitive DNA and regulating replicative cell aging. The goal of this comprehensive review is to distill a wide array of biochemical, molecular genetic, cell biological, and genomics studies down to the “nuts and bolts” of silent chromatin and the processes that yield transcriptional silencing. PMID:27516616
Stainless steels for cryogenic bolts and nuts (in French)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Leroy, F.; Rabbe, P.; Odin, G.
1975-03-01
Stainless steel for cryogenic applications are generally austenitic steels which, under the effect of cold-drawing, can or cannot undergo a partial martensitic transformation according to their composition. It has been shown that very high ductility and endurance characteristics at low temperatures, together with very high yield strength and resistances values, can be attained with grades of nitrogenous steels of types Z2CN18-10N and Z3CMN18-8-6N. Optimum ductility values are obtained by employing to the best possible, the martensitic transformations which develop during cold-drawing. From the plotting of the rational traction curves, it is possible to analyse very simply the influence of themore » composition on the martensitic transformations. (FR)« less
NASA Task Load Index (TLX). Volume 1.0; Computerized Version
NASA Technical Reports Server (NTRS)
Hart, Sandra G.
1986-01-01
This booklet and the accompanying diskette contain the materials necessary to collect subjective workload assessments with the NASA Task Load Index on IBM PC compatible microcomputers. This procedure for collecting workload ratings was developed by the Human Performance Group at NASA Ames Research Center during a three year research effort that involved more than 40 laboratory, simulation, and inflight experiments Although the technique is still undergoing evaluation, this package is being distributed to allow other researchers to use it in their own experiments Comments or suggestions about the procedure would be greatly appreciated This package is intended to fill a "nuts and bolts" function of describing the procedure. A bibliography provides background information about previous empirical findings and the logic that supports the procedure.
The Nuts and Bolts of Food Immunotherapy: The Future of Food Allergy
Anagnostou, Katherine
2018-01-01
Food allergies are on the rise and have a major impact on the quality of life of the food allergic child and their family. Currently, the mainstream treatment for food allergies is strict avoidance and elimination of the allergenic food(s) from the patient’s diet in order to prevent an allergic reaction. However, recent advances in research have presented new therapeutic options for food allergic patients that are potentially becoming promising alternatives to traditional treatment. Food immunotherapy is the most popular of these new emerging interventions and has been studied intensively over the last decade for various foods. In this review, we discuss this exciting new development that is aspiring to become part of the mainstream therapy for food allergy. PMID:29617351
High-dose-rate intraoperative radiation therapy: the nuts and bolts of starting a program
Moningi, Shalini; Armour, Elwood P.; Terezakis, Stephanie A.; Efron, Jonathan E.; Gearhart, Susan L.; Bivalacqua, Trinity J.; Kumar, Rachit; Le, Yi; Kien Ng, Sook; Wolfgang, Christopher L.; Zellars, Richard C.; Ellsworth, Susannah G.; Ahuja, Nita
2014-01-01
High-dose-rate intraoperative radiation therapy (HDR-IORT) has historically provided effective local control (LC) for patients with unresectable and recurrent tumors. However, IORT is limited to only a few specialized institutions and it can be difficult to initiate an HDR-IORT program. Herein, we provide a brief overview on how to initiate and implement an HDR-IORT program for a selected group of patients with gastrointestinal and pelvic solid tumors using a multidisciplinary approach. Proper administration of HDR-IORT requires institutional support and a joint effort among physics staff, oncologists, surgeons, anesthesiologists, and nurses. In order to determine the true efficacy of IORT for various malignancies, collaboration among institutions with established IORT programs is needed. PMID:24790628
Biological Nanomotors with a Revolution, Linear, or Rotation Motion Mechanism
Noji, Hiroyuki; Yengo, Christopher M.; Zhao, Zhengyi; Grainge, Ian
2016-01-01
SUMMARY The ubiquitous biological nanomotors were classified into two categories in the past: linear and rotation motors. In 2013, a third type of biomotor, revolution without rotation (http://rnanano.osu.edu/movie.html), was discovered and found to be widespread among bacteria, eukaryotic viruses, and double-stranded DNA (dsDNA) bacteriophages. This review focuses on recent findings about various aspects of motors, including chirality, stoichiometry, channel size, entropy, conformational change, and energy usage rate, in a variety of well-studied motors, including FoF1 ATPase, helicases, viral dsDNA-packaging motors, bacterial chromosome translocases, myosin, kinesin, and dynein. In particular, dsDNA translocases are used to illustrate how these features relate to the motion mechanism and how nature elegantly evolved a revolution mechanism to avoid coiling and tangling during lengthy dsDNA genome transportation in cell division. Motor chirality and channel size are two factors that distinguish rotation motors from revolution motors. Rotation motors use right-handed channels to drive the right-handed dsDNA, similar to the way a nut drives the bolt with threads in same orientation; revolution motors use left-handed motor channels to revolve the right-handed dsDNA. Rotation motors use small channels (<2 nm in diameter) for the close contact of the channel wall with single-stranded DNA (ssDNA) or the 2-nm dsDNA bolt; revolution motors use larger channels (>3 nm) with room for the bolt to revolve. Binding and hydrolysis of ATP are linked to different conformational entropy changes in the motor that lead to altered affinity for the substrate and allow work to be done, for example, helicase unwinding of DNA or translocase directional movement of DNA. PMID:26819321
78 FR 8058 - Airworthiness Directives; Fokker Services B.V. Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2013-02-05
... torque values of nuts on circuit breakers, contactors, and terminal blocks of the electrical power center... loose nuts, which could result in arcing and potentially an onboard fire, possibly resulting in damage... were issued, several operators reported finding loose nuts on contactors in the EPC of Fokker 50/60...
Nishimura, Takuma; Hosaka, Hiroshi; Morita, Takeshi
2012-01-01
The Smooth Impact Drive Mechanism (SIDM) is a linear piezoelectric actuator that has seen practically applied to camera lens modules. Although previous SIDM actuators are easily miniaturized and enable accurate positioning, these actuators cannot actuate at high speed and cannot provide powerful driving because they are driven at an off-resonant frequency using a soft-type PZT. In the present study, we propose a resonant-type SIDM using a bolt-clamped Langevin transducer (BLT) with a hard-type PZT. The resonant-type SIDM overcomes the above-mentioned problems and high-power operation becomes possible with a very simple structure. As a result, we confirmed the operation of resonant-type SIDM by designing a bolt-clamped Langevin transducer. The properties of no-load maximum speed was 0.28m/s at driving voltages of 80V(p-p) for 44.9kHz and 48V(p-p) for 22.45kHz with a pre-load of 3.1N. Copyright © 2011 Elsevier B.V. All rights reserved.
Tool for Coupling a Torque Wrench to a Round Cable Connector
NASA Technical Reports Server (NTRS)
Hacker, Scott C.; Dean, Richard J.; Burge, Scott W.
2006-01-01
A tool makes it possible to couple a torque wrench to an externally knurled, internally threaded, round cable connector. The purpose served by the tool is to facilitate the tightening of multiple such connectors (or the repeated tightening of the same connector) to repeatable torques. The design of a prior cable-connector/ torque-wrench coupling tool provided for application of the torque-wrench jaws to a location laterally offset from the axis of rotation of the cable connector, making it necessary to correct the torque reading for the offset. Unlike the design of the prior tool, the design of the present tool provides for application of the torque-wrench jaws to a location on the axis of rotation, obviating correction of the torque reading for offset. The present tool (see figure) consists of a split collet containing a slot that provides clearance for inserting and bending the cable, a collet-locking sleeve, a collet-locking nut, and a torque-wrench adaptor that is press-fit onto the collet. Once the collet is positioned on the cable connector, the collet-locking nut is turned to force the collet-locking sleeve over the collet, compressing the collet through engagement of tapered surfaces on the outside of the collet and the inside of the locking sleeve. Because the collet is split and therefore somewhat flexible, this compression forces the collet inward to grip the connector securely. The torque wrench is then applied to the torque-wrench adaptor in the usual manner for torquing a nut or a bolt.
Nuts and Bolts - Techniques for Genesis Sample Curation
NASA Technical Reports Server (NTRS)
Burkett, Patti J.; Rodriquez, M. C.; Allton, J. H.
2011-01-01
The Genesis curation staff at NASA Johnson Space Center provides samples and data for analysis to the scientific community, following allocation approval by the Genesis Oversight Committee, a sub-committee of CAPTEM (Curation Analysis Planning Team for Extraterrestrial Materials). We are often asked by investigators within the scientific community how we choose samples to best fit the requirements of the request. Here we will demonstrate our techniques for characterizing samples and satisfying allocation requests. Even with a systematic approach, every allocation is unique. We are also providing updated status of the cataloging and characterization of solar wind collectors as of January 2011. The collection consists of 3721 inventoried samples consisting of a single fragment, or multiple fragments containerized or pressed between post-it notes, jars or vials of various sizes.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wilson, A.
2001-05-16
Greening Federal Facilities, Second Edition, is a nuts-and-bolts resource guide compiled to increase energy and resource efficiency, cut waste, and improve the performance of Federal buildings and facilities. The guide highlights practical actions that facility managers, design and construction staff, procurement officials, and facility planners can take to save energy and money, improve the comfort and productivity of employees, and benefit the environment. It supports a national effort to promote energy and environmental efficiency in the nation's 500,000 Federal buildings and facilities. Topics covered include current Federal regulations; environmental and energy decision-making; site and landscape issues; building design; energy systems;more » water and wastewater; materials; waste management, and recycling; indoor environmental quality; and managing buildings.« less
Structural health monitoring using a hybrid network of self-powered accelerometer and strain sensors
NASA Astrophysics Data System (ADS)
Alavi, Amir H.; Hasni, Hassene; Jiao, Pengcheng; Lajnef, Nizar
2017-04-01
This paper presents a structural damage identification approach based on the analysis of the data from a hybrid network of self-powered accelerometer and strain sensors. Numerical and experimental studies are conducted on a plate with bolted connections to verify the method. Piezoelectric ceramic Lead Zirconate Titanate (PZT)-5A ceramic discs and PZT-5H bimorph accelerometers are placed on the surface of the plate to measure the voltage changes due to damage progression. Damage is defined by loosening or removing one bolt at a time from the plate. The results show that the PZT accelerometers provide a fairly more consistent behavior than the PZT strain sensors. While some of the PZT strain sensors are not sensitive to the changes of the boundary condition, the bimorph accelerometers capture the mode changes from undamaged to missing bolt conditions. The results corresponding to the strain sensors are better indicator to the location of damage compared to the accelerometers. The characteristics of the overall structure can be monitored with even one accelerometer. On the other hand, several PZT strain sensors might be needed to localize the damage.
Arts-inspired students sync their assets to a nuts and bolts world: A career mentoring pilot progam
NASA Astrophysics Data System (ADS)
Hudson, Lynn
This research examined how students who are arts-inspired feel about their futures in a STEM-based work climate. Science, Technology, Engineering, and Math are the nuts and bolts, and in education today, the only avenue touted for our country and our students' success in this 21st century economy. This can be disconcerting to those interested in other fields, like the arts. This study was guided by the following questions in an effort to understand if our artists and arts-inspired students realize their options and importance in this 21st century climate. The pilot study was designed to help improve the students' perception of their abilities or self-efficacy in the STEM areas by introducing STEM professionals as mentors who designed hands-on activities that simulate work in the STEM fields. Research Questions: 1. Do arts-inspired students have an interest in a STEM career area prior to participating in the career mentoring program? 2. Does participation in a STEM career mentoring program improve student's self-efficacy in STEM fields? 3. Does participation in STEM career mentoring program increase student's interest in pursuing STEM-related careers? Lent, Brown and Hackett's Social Cognitive Career Theory and Daniel Pink's, "A Whole New Mind: Why Left-Brainers Will Rule the Future" were used as the theoretical framework for this study. Seventeen African-American girls who were enrolled in the "I AM COMPLETE" summer program participated in the pilot study. Data was collected from the College Foundation of North Carolina Career Interest Explorer and the STEM Career Interest Survey, which served as a pre and post-test. This pilot offered limited support for the hypothesis, however, career mentoring and opportunities for young people to experience careers, especially in the STEM areas must continue to grow. The role that the arts play in this process is pivotal in galvanizing females and minorities to join these professions. It is the hope of this researcher that the pilot be replicated using a much larger population of students and school communities.
Development of Live-working Robot for Power Transmission Lines
NASA Astrophysics Data System (ADS)
Yan, Yu; Liu, Xiaqing; Ren, Chengxian; Li, Jinliang; Li, Hui
2017-07-01
Dream-I, the first reconfigurable live-working robot for power transmission lines successfully developed in China, has the functions of autonomous walking on lines and accurately positioning. This paper firstly described operation task and object of the robot; then designed a general platform, an insulator replacement end and a drainage plate bolt fastening end of the robot, presented a control system of the robot, and performed simulation analysis on operation plan of the robot; and finally completed electrical field withstand voltage tests in a high voltage hall as well as online test and trial on actual lines. Experimental results show that by replacing ends of manipulators, the robot can fulfill operation tasks of live replacement of suspension insulators and live drainage plate bolt fastening.
Behavior of Fiber Glass Bolts, Rock Bolts and Cable Bolts in Shear
NASA Astrophysics Data System (ADS)
Li, Xuwei; Aziz, Naj; Mirzaghorbanali, Ali; Nemcik, Jan
2016-07-01
This paper experimentally compares the shear behavior of fiber glass (FG) bolt, rock bolt (steel rebar bolt) and cable bolt for the bolt contribution to bolted concrete surface shear strength, and bolt failure mode. Two double shear apparatuses of different size were used for the study. The tensile strength, the shear strength and the deformation modulus of bolt control the shear behavior of a sheared bolted joint. Since the strength and deformation modulus of FG bolt, rock bolt and cable bolt obtained from uniaxial tensile tests are different, their shear behavior in reinforcing joints is accordingly different. Test results showed that the shear stiffness of FG bolted joints decreased gradually from the beginning to end, while the shear stiffness of joints reinforced by rock bolt and cable bolt decreased bi-linearly, which is clearly consistent with their tensile deformation modulus. The bolted joint shear stiffness was highly influenced by bolt pretension in the high stiffness stage for both rock bolt and cable bolt, but not in the low stiffness stage. The rock bolt contribution to joint shear strength standardised by the bolt tensile strength was the largest, followed by cable bolts, then FG bolts. Both the rock bolts and cable bolts tended to fail in tension, while FG bolts in shear due to their low shear strength and constant deformation modulus.
Mendoza Velázquez, Alfonso
2012-01-01
Develop the Index of Nutritional Purchasing Power Parity (Nut3-CiO) as an instrument to compare the caloric costs of a healthy versus an unhealthy diet between regions or cities in a country over time. Indices of caloric prices were constructed and the "law of one price" was used to derive the Nut3-CiO index. Caloric inflation rates were obtained using basic descriptive statistics. The Nut3-CiO was applied in the major cities of Mexico during the period from January 1996 to December 2010. The statistical behavior of the Nut3-CiO revealed that, in Mexican cities, products for a typical diet are less expensive than products for a healthy diet. The findings showed a cyclical behavior to the index, a high correlation between inflation for the typical diet and inflation for the market basket, and a high persistence of prices. The Nut3-CiO index makes it possible to periodically compare the price differential of two types of diets-typical and healthy-between cities in a single country. This instrument could help health authorities identify the cities where it is easier or more difficult for consumers to access a typical or healthy diet in terms of cost. Furthermore, it makes it possible to estimate the percentage adjustment necessary in each city to attain levels of nutritional purchasing power parity.
Planning and acquiring a national center for the United States Geological Survey
Schmidt, William A.
1993-01-01
This history of building a National Center for the U.S. Geological Survey is a "nuts and bolts" account of the planning, design and construction, forgotten happenings, and frustrations in the planning and authorization process, and the political and other considerations which played a significant role in the culmination of a dream about a National Center for the Geological Survey. This documented data of unique procedures in the acquisition and financing of Federal buildings, the choice and development of the building site, and its location as a contribution to the enhancement of the "new town" concept of the 1960's in the planning and development of the National Capital Area, may well provide guidance in the future to those who have to decide whether a building of true worth should be preserved.
NASA Technical Reports Server (NTRS)
Wingett, Paul (Inventor)
2001-01-01
A mounting assembly for mounting a composite pressure vessel to a vehicle includes a saddle having a curved surface extending between two pillars for receiving the vessel. The saddle also has flanged portions which can be bolted to the vehicle. Each of the pillars has hole in which is mounted the shaft portion of an attachment member. A resilient member is disposed between each of the shaft portions and the holes and loaded by a tightening nut. External to the holes, each of the attachment members has a head portion to which a steel band is attached. The steel band circumscribes the vessel and translates the load on the springs into a clamping force on the vessel. As the vessel expands and contracts, the resilient members expand and contract so that the clamping force applied by the band to the vessel remains constant.
Sealed Plant-Growth Chamber For Clinostat
NASA Technical Reports Server (NTRS)
Brown, Christopher S.; Dreschel, Thomas W.
1993-01-01
Laboratory chamber for growing plants used to measure photosynthesis and respiration in simulated microgravity. Holds plant specimens while rotated on clinostat, see article, "Clinostat Delivers Power To Plant-Growth Cabinets" (KSC-11537). Provides way of comparing gas-exchange rates of plants rotated horizontally on clinostat with those of stationary or vertically rotated plants. Gas extracted for analysis without stopping clinostat. Chamber includes potlike base and cylindrical cover, both made of transparent acrylic pipe. Gasket forms seal between cover and bottom plate of base. Cover bolted to pot baseplate, which in turn bolted to clinostat.
29 CFR 1917.49 - Spouts, chutes, hoppers, bins, and associated equipment.
Code of Federal Regulations, 2013 CFR
2013-07-01
... turned off, locked out and tagged. (3) The employee entering the bin wears a lifeline and safety harness... equipment to be used. The inspection shall include at least the eye bolts, wires, and sheaves. (2) Power... adjustments are made to a power shovel, wire, or associated equipment, the power supply to the shovel shall be...
29 CFR 1917.49 - Spouts, chutes, hoppers, bins, and associated equipment.
Code of Federal Regulations, 2012 CFR
2012-07-01
... turned off, locked out and tagged. (3) The employee entering the bin wears a lifeline and safety harness... equipment to be used. The inspection shall include at least the eye bolts, wires, and sheaves. (2) Power... adjustments are made to a power shovel, wire, or associated equipment, the power supply to the shovel shall be...
29 CFR 1917.49 - Spouts, chutes, hoppers, bins, and associated equipment.
Code of Federal Regulations, 2014 CFR
2014-07-01
... turned off, locked out and tagged. (3) The employee entering the bin wears a lifeline and safety harness... equipment to be used. The inspection shall include at least the eye bolts, wires, and sheaves. (2) Power... adjustments are made to a power shovel, wire, or associated equipment, the power supply to the shovel shall be...
Ye, Jianglei
2017-09-08
A novel solid phase extraction (SPE) device driven by positive pressure was developed instead of negative pressure from a vacuum pump, in order to enrich organo chlorinated and pyrethroid pesticides in seawater. The water sampling bottles and the pipelines which touch water samples were made of plastic material without chlorine. In order to ensure the sealing and firmness, the whole device were tightened with nut and bolt. The inner pressure (0.1-0.3 MPa) in the water sampling bottle was provided by the small air pump (powered by 12 V cell) controlled by a microprogrammed control unit (MCU) and pressure sensor to keep the water flow rate (4.0-6.0 mL/min). The pre-conditioned SPE column can be used for the enrichment of pesticides within four weeks, and the loaded SPE column can be eluted for detection within six weeks with recoveries greater than 80%. The linearity of the method was good with the correlation coefficient more than 0.9. The limits of quantification (LOQs) were 0.8-6 ng/L. The recoveries of the pesticides at three spiked levels (3 parallel samples) were 86.1%-95.5% with the relative standard deviations less than 10%. The benzene hexachlorides (BHCs) and dichloro-diphenyl-trichloroethanes (DDTs) were detected in seawater samples. The device has good application in enriching organo chlorinated and pyrethroid pesticides in seawater.
Torque Limit for Bolted Joint for Composites. Part A; TTTC Properties of Laminated Composites
NASA Technical Reports Server (NTRS)
Zhao, Yi
2003-01-01
The existing design code for torque limit of bolted joints for composites at Marshall Space Flight Center is MSFC-STD-486B, which was originally developed in 1960s for metallic materials. The theoretical basis for this code was a simplified mechanics analysis, which takes into account only the bolt, nut and washers, but not the structural members to be connected. The assumption was that metallic materials would not fail due to the bearing stress at the contact area between washer and the mechanical member. This is true for metallic materials; but for composite materials the results could be completely different. Unlike most metallic materials, laminated composite materials have superior mechanical properties (such as modulus and strength) in the in-plane direction, but not in the out-of-plane, or through-the-thickness (TTT) direction. During the torquing, TTT properties (particularly compressive modulus and compressive strength) play a dominant role in composite failure. Because of this concern, structural design engineers at Marshall are currently using a compromised empirical approach: using 50% of the torque value for composite members. Companies like Boeing is using a similar approach. An initial study was conducted last summer on this topic to develop theoretical model(s) that takes into consideration of composite members. Two simplified models were developed based on stress failure criterion and strain failure criterion, respective. However, these models could not be used to predict the torque limit because of the unavailability of material data, specifically, through-the-thickness compression (TTTC) modulus and strength. Therefore, the task for this summer is to experimentally determine the TTTC properties. Due to the time limitation, only one material has been tested: IM7/8552 with [0 degrees,plus or minus 45 degrees, 90 degree ] configuration. This report focuses the test results and their significance, while the experimentation will be described in a separate report by Mr. Kris Kostreva.
Rotation Capacity of Bolted Flush End-Plate Stiffened Beam-to-Column Connection
NASA Astrophysics Data System (ADS)
Ostrowski, Krzysztof; Kozłowski, Aleksander
2017-06-01
One of the flexibility parameters of semi-rigid joints is rotation capacity. Plastic rotation capacity is especially important in plastic design of framed structures. Current design codes, including Eurocode 3, do not posses procedures enabling designers to obtain value of rotation capacity. In the paper the calculation procedure of the rotation capacity for stiffened bolted flush end-plate beam-to-column connections has been proposed. Theory of experiment design was applied with the use of Hartley's PS/DS-P:Ha3 plan. The analysis was performed with the use of finite element method (ANSYS), based on the numerical experiment plan. The determination of maximal rotation angle was carried out with the use of regression analysis. The main variables analyzed in parametric study were: pitch of the bolt "w" (120-180 mm), the distance between the bolt axis and the beam upper edge cg1 (50-90 mm) and the thickness of the end-plate tp (10-20 mm). Power function was proposed to describe available rotation capacity of the joint. Influence of the particular components on the rotation capacity was also investigated. In the paper a general procedure for determination of rotation capacity was proposed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Czarnecki, R M
1987-05-01
Guidelines have been developed to evaluate the seismic adequacy of the anchorage of various classes of electrical and mechanical equipment in nuclear power plants covered by NRC Unresolved Safety Issue A-46. The guidelines consist of screening tables that give the seismic anchorage capacity as a function of key equipment and anchorage fasteners, inspection checklists for field verification of anchorage adequacy, and provisions for outliers that can be used to further investigate anchorages that cannot be verified in the field. The screening tables are based on an analysis of the anchorage forces developed by common equipment types and on strength criteriamore » to quantify the holding power of anchor bolts and welds. The strength criteria for expansion anchor bolts were developed by collecting and analyzing a large quantity of test data.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Czarnecki, R M
1987-05-01
Guidelines have been developed to evaluate the seismic adequacy of the anchorage of various classes of electrical and mechanical equipment in nuclear power plants covered by NRC Unresolved Safety Issue A-46. The guidelines consist of screening tables that give the seismic anchorage capacity as a function of key equipment and anchorage fasteners, inspection checklists for field verification of anchorage adequacy, and provisions for outliers that can be used to further investigate anchorages that cannot be verified in the field. The screening tables are based on an analysis of the anchorage forces developed by common equipment types and on strength criteriamore » to quantify the holding power of anchor bolts and welds. The strength criteria for expansion anchor bolts were developed by collecting and analyzing a large quantity of test data.« less
CIBO frets most about nuts and bolts
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1979-12-24
The Environmental Protection Agency may reduce the fuel-emission standards for new boilers because the Council of Industrial Boiler Owners (CIBO) claims the standards assume stacks that are higher than those used for coal-fired boilers. CIBO is unique in concentrating on furnishing technical information rather than on broad policy issues. The group sees fuel utilization rather than fuel supply issues as an area in which it can have the greatest influence. Organized in response to President Carter's 1978 proposals for coal conversion, followed by the Fuel Use Act and the Clean Air Act Amendments, CIBO spokesmen are critical of the conversionmore » emphasis and feel the regulations should concentrate on new equipment. The group's efforts will be directed at changing fuel-use regulations, helping users get exemptions, and finding ways for users to accommodate the regulations. It supports implementation of the Clean Air Act, although it recommends a relaxed timetable. (DCK)« less
New Insights Into “Plant Memories”
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sanbonmatsu, Karissa
A special stretch of ribonucleic acid (RNA) called COOLAIR is revealing its inner structure and function to scientists, displaying a striking resemblance to an RNA molecular machine, territory previously understood to be limited to the cells’ protein factory (the ‘ribosome’) and not a skill set given to mere strings of RNA. “We are uncovering the nuts and bolts of plant memories,” said Karissa Sanbonmatsu of Los Alamos National Laboratory, lead author on a new article this week in the journal Cell Reports. In the past 5 years or so, material in the cell known as “junk DNA” had actually turnedmore » out not to be junk at all. Instead, it was shown to produce RNA molecules that play key roles in the development of organs in the embryo, as well as affecting cancer, brain function and plant biology.« less
401. Westinghouse plans a smaller 501
DOE Office of Scientific and Technical Information (OSTI.GOV)
Barker, T.
1996-11-01
In concept, the recently announced 84-MW Westinghouse 401 is a smaller-scale 501G heavy-frame gas turbine. (The scaling factor is 0.64:1.) It will share design features with the larger 501F and G, including a two-bearing rotor, horizontally-split casing, cold-end drive, and axial exhaust, but there will be no common components apart from some nuts and bolts. From a marketing standpoint, the new 84-MW engine is intended to occupy the market niche between the 110-MW 501 D, and the 49-MW 251B11/12. The engineers` design goals, as always, were high combined cycle efficiency, low life cycle cost and low cost of electricity, allmore » good reasons for working from the proven and successful 501s. The first 401 is scheduled to be shipped from Westinghouse`s Hamilton, Ontario, Canada plant in March 1998. 2 figs.« less
Investigation of the effects of extravehicular activity (EVA) gloves on performance
NASA Technical Reports Server (NTRS)
Bishu, Ram R.; Klute, Glenn
1993-01-01
The objective was to assess the effects of extravehicular activity (EVA) gloves at different pressures on human hand capabilities. A factorial experiment was performed in which three types of EVA gloves were tested at five pressure differentials. The independent variables tested in this experiment were gender, glove type, pressure differential, and glove make. Six subjects participated in an experiment where a number of dexterity measures, namely time to tie a rope, and the time to assemble a nut and bolt were recorded. Tactility was measured through a two point discrimination test. The results indicate that with EVA gloves strength is reduced by nearly 50 percent, there is a considerable reduction in dexterity, performance decrements increase with increasing pressure differential, and some interesting gender glove interactions were observed, some of which may have been due to the extent (or lack of) fit of the glove to the hand. The implications for the designer are discussed.
The nuts and bolts of pills and portions: the functions of a drug safety working group.
Nath, Noleen S; Jones, Ellen H; Stride, Peter; Premaratne, Manuja; Thaker, Darshit; Lim, Ivan
2011-11-01
Hospitalised patients commonly experience adverse drug events (ADEs) and medication errors. Runciman reported that ADEs in hospitals account for 20% of reported adverse events and contribute to 27% of deaths where death followed an adverse event. Hughes recommends multidisciplinary hospital drug committees to assess performance and raise standards. The new Code of Conduct of the Medical Board of Australia recommends participation in systems for surveillance and monitoring of adverse events, and to improve patient safety. We describe the functions and role of a Drug Safety Working Group (DSWG) in a suburban hospital, which aims to audit and promote a culture of prescribing and medication administration that is prudent and cautious to minimise the risk of harm to patients. We believe that regular prescription monitoring and feedback to Resident Medical Officers (RMOs) improves medication management in our hospital.
CONTROL ROD ROTATING MECHANISM
Baumgarten, A.; Karalis, A.J.
1961-11-28
A threaded rotatable shaft is provided which rotates in response to linear movement of a nut, the shaft being surrounded by a pair of bellows members connected to either side of the nut to effectively seal the reactor from leakage and also to store up energy to shut down the reactor in the event of a power failure. (AEC)
Failures in large gas turbines due to liquid-metal embrittlement
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cameron, D.W.
1994-07-01
The failures of three gas turbine components, attributed to liquid-metal embrittlement or solid-metal-induced embrittlement, are described. High temperatures inherent in the gas turbine can aggravate these phenomenon if the necessary conditions are present. Examples chosen include a power transmission shaft, flange bolts from a cooling steam line, and a turbine rotor bolt. The respective material couples involved are 17-4PH stainless steel-copper, AISI 4130-cadmium, and IN 718-cadmium. Each case includes information on the source of the aggressive material and relevant operating environment. The implications of the failures with regard to the general failure mechanism are briefly discussed.
Audio-based bolt-loosening detection technique of bolt joint
NASA Astrophysics Data System (ADS)
Zhang, Yang; Zhao, Xuefeng; Su, Wensheng; Xue, Zhigang
2018-03-01
Bolt joint, as the commonest coupling structure, is widely used in electro-mechanical system. However, it is the weakest part of the whole system. The increase of preload tension force can raise the reliability and strength of the bolt joint. Therefore, the pretension force is one of the most important factors to ensure the stability of bolt joint. According to the way of generating pretension force, the pretension force can be monitored by bolt torque, degrees and elongation. The existing bolt-loosening monitoring methods all require expensive equipment, which greatly restricts the practicality of the bolt-loosening monitoring. In this paper, a new method of bolt-loosening detection technique based on audio is proposed. The sound that bolt is hit by a hammer is recorded on the Smartphone, and the collected audio signal is classified and identified by support vector machine algorithm. First, a verification test was designed and the results show that this new method can identify the damage of bolt looseness accurately. Second, a variety of bolt-loosening was identified. The results indicate that this method has a high accuracy in multiclass classification of the bolt looseness. This bolt-loosening detection technique based on audio not only can reduce the requirements of technical and professional experience, but also make bolt-loosening monitoring simpler and easier.
NASA Astrophysics Data System (ADS)
Tesfa, B.; Horler, G.; Thobiani, F. Al; Gu, F.; Ball, A. D.
2012-05-01
Many industrial structures associated with railway infrastructures rely on a large number of bolted joint connections to ensure safe and reliable operation of the track and trackside furniture. Significant sums of money are spent annually to repair the damage caused by bolt failures and to maintain the integrity of bolted structures. In the UK, Network Rail (the organization responsible for rail network maintenance and safety) conducts corrective and preventive maintenance manually on 26,000 sets of points (each having approximately 30 bolted joints per set), in order to ensure operational success and safety for the travelling public. Such manual maintenance is costly, disruptive, unreliable and prone to human error. The aim of this work is to provide a means of automatically measuring the clamping force of each individual bolted joint, by means of an instrumented washer. This paper describes the development of a sensor means to be used in the washer, which satisfies the following criteria. Sense changes in the clamping force of the joint and report this fact. Provide compatibility with the large dynamic range of clamping force. Satisfy the limitations in terms of physical size. Provide the means to electronically interface with the washer. Provide a means of powering the washer in situ. Provide a solution at an acceptable cost. Specifically the paper focuses on requirements 1, 2 and 3 and presents the results that support further development of the proposed design and the realization of a pre-prototype system. In the paper, various options for the force sensing element (strain gage, capacitor, piezo-resistive) have been compared, using design optimization techniques. As a result of the evaluation, piezo-resistive sensors in concert with a proprietary force attenuation method, have been found to offer the best performance and cost trade-off The performance of the novel clamping force sensor has been evaluated experimentally and the results show that a smart washer can be developed to monitor the condition of bolted joints as found on railway track and points.
Parametric Study of Single Bolted Composite Bolted Joint Subjected to Static Tensile Loading
NASA Astrophysics Data System (ADS)
Awadhani, L. V.; Bewoor, Anand, Dr.
2017-08-01
The use of composites is increasing in the engineering applications in order to reduce the weight, building energy efficient systems, designing a suitable material according to the requirements of the application. But at the same time, building a structure is possible only by bonding or bolting or combination of them. There are limitations for the bonding methods and problems with the bolting such as stress concentration near the neighborhood of the bolt hole, tensile or shear failure, delamination etc. Hence the design of a composite bolted structure needs a special attention. This paper focuses on the performance of the composite bolted joint under static tensile loading and the effect of variation in the parameters such as the bolt pitch, plate width, thickness, bolt tightening torque, composite material, coefficient of friction between the bolt and plate etc. A simple spring mass model is used to study the single bolted composite bolted joint. The influencing parameters are identified through the developed model and compared with the results from the literature. The best geometric parameters for the applied load are identified for the composite bolted joints.
Mold bolt and means for achieving close tolerances between bolts and bolt holes
NASA Technical Reports Server (NTRS)
Johnston, David L. (Inventor); Bryant, Phillip G. (Inventor)
1993-01-01
In the space shuttle, a cargo bay storage rack was required which was to be manufactured from a metal-plastic composite and bolted to a cargo structure. Following completion, utilization of the rack was disallowed due to tolerances, that is, the size differences between the outside bolt diameter and the inside hole diameter. In addition to the space shuttle problem there are other close tolerance requirements for bolts. Such environments often benefit from close tolerance bolting. Frequently such fabrication is not cost effective. Consequently there is a need for means of achieving close tolerances between bolts and bolt holes. Such means are provided. After compressing the elements together a strong rigid plastic, ceramic, or ceramic plastic fluid is forced into a channel extending through the bolt.
Bolted Double-Lap Composite Joints Under Mechanical and Thermal Loading
NASA Technical Reports Server (NTRS)
Kradinov, V.; Barut, A.; Madenci, E.; Walker, Sandra P. (Technical Monitor)
2000-01-01
This study concerns the determination of the contact stresses and contact region around bolt holes and the bolt load distribution in single- and double-lap joints of composite laminates with arbitrarily located bolts under general mechanical loading conditions and uniform temperature change. The unknown contact stress distribution and contact region between the bolt and laminates and the interaction among the bolts require the bolt load distribution, as well as the contact stresses, to be as part of the solution. The present method is based on the complex potential theory and the variational formulation in order to account for bolt stiffness, bolt-hole clearance, and finite geometry of the composite laminates.
Waveguide Power-Amplifier Module for 80 to 150 GHz
NASA Technical Reports Server (NTRS)
Samoska, Lorene; Weinreb, Sander; Peralta, Alejandro
2006-01-01
A waveguide power-amplifier module capable of operating over the frequency range from 80 to 150 GHz has been constructed. The module comprises a previously reported power amplifier packaged in a waveguide housing that is compatible with WR-8 waveguides. (WR- 8 is a standard waveguide size for the nominal frequency range from 90 to 140 GHz.) The waveguide power-amplifier module is robust and can be bolted to test equipment and to other electronic circuits with which the amplifier must be connected for normal operation.
Seismic verification of nuclear plant equipment anchorage, Revision 1
DOE Office of Scientific and Technical Information (OSTI.GOV)
Czarnecki, R M
1991-06-01
Guidelines have been developed to evaluate the seismic adequacy of the anchorage of various classes of electrical and mechanical equipment in nuclear power plants covered by NRC Unresolved Safety Issue A-46. The guidelines consist of anchorage strength capacities as a function of key equipment and installation parameters. The strength criteria for expansion anchor bolts were developed by collecting and analyzing a large quantity of test data. The strength criteria for Cast-in-Place bolts and welds to embedded steel plates and channels were taken from existing nuclear-industry design guidelines. For anchorage used in low strength concrete and in concrete with cracks, appropriatemore » strength reduction factors were developed. Reduction factors for parameters such as edge distance, spacing and embedment depth are also included. Based on the anchorage capacity and equipment configuration, inspection checklists for field verification of anchorage adequacy were developed, and provisions for outliners that can be used to further investigate anchorages that cannot be verified in the field were prepared. The screening tables are based on an analysis of the anchorage forces developed by common equipment types and on strength criteria to quantify the holding power of anchor bolts and welds. A computer code EBAC was developed for the evaluation of the adequacy of the equipment anchorage. Guidelines to evaluate anchorage adequacy for vertical and horizontal tanks and horizontal heat exchangers were also developed.« less
Measuring mine roof bolt strains
Steblay, Bernard J.
1986-01-01
A mine roof bolt and a method of measuring the strain in mine roof bolts of this type are disclosed. According to the method, a flat portion on the head of the mine roof bolt is first machined. Next, a hole is drilled radially through the bolt at a predetermined distance from the bolt head. After installation of the mine roof bolt and loading, the strain of the mine roof bolt is measured by generating an ultrasonic pulse at the flat portion. The time of travel of the ultrasonic pulse reflected from the hole is measured. This time of travel is a function of the distance from the flat portion to the hole and increases as the bolt is loaded. Consequently, the time measurement is correlated to the strain in the bolt. Compensation for various factors affecting the travel time are also provided.
Metallurgical failure analysis of MH-1A reactor core hold-down bolts. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hawthorne, J.R.; Watson, H.E.
1976-11-01
The Naval Research Laboratory has performed a failure analysis on two MH-1A reactor core hold-down bolts that broke in service. Adherence to fabrication specifications, post-service properties and possible causes of bolt failure were investigated. The bolt material was verified as 17-4PH precipitation hardening stainless steel. Measured bolt dimensions also were in accordance with fabrication drawing specifications. Bolt failure occurred in the region of a locking pin hole which reduced the bolt net section by 47 percent. The failure analysis indicates that the probable cause of failure was net section overloading resulting from a lateral bending force on the bolt. Themore » analysis indicates that net section overloading could also have resulted from combined tensile stresses (bolt preloading plus differential thermal expansion). Recommendations are made for improved bolting.« less
Universal Assembly for Captive Bolts
NASA Technical Reports Server (NTRS)
Marke, M. L.; Hagopian, B.
1982-01-01
New method allows for virtually any bolt to be easily converted to "captive" bolt. Method eliminates need for separate design for each application. Cup-shaped washer that is flattened secures tap to bolt. Wire attached to tab holds bolt assembly captive. Flattening washer can also be done during installation of bolt. Wash, tab and spacer are all made of corrosion-resistant steel.
Chandrasekara, Neel; Shahidi, Fereidoon
2011-05-11
The effect of roasting on the content of phenolic compounds and antioxidant properties of cashew nuts and testa was studied. Whole cashew nuts, subjected to low-temperature (LT) and high-temperature (HT) treatments, were used to determine the antioxidant activity of products. Antioxidant activities of cashew nut, kernel, and testa phenolics extracted increased as the roasting temperature increased. The highest activity, as determined by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity, oxygen radical absorbance capacity (ORAC), hydroxyl radical scavenging capacity, Trolox equivalent antioxidant activity (TEAC), and reducing power, was achieved when nuts were roasted at 130 °C for 33 min. Furthermore, roasting increased the total phenolic content (TPC) in both the soluble and bound extracts from whole nut, kernel, and testa but decreased that of the proanthocyanidins (PC) except for the soluble extract of cashew kernels. In addition, cashew testa afforded a higher extract yield, TPC, and PC in both soluble and bound fractions compared to that in whole nuts and kernels. Phenolic acids, namely, syringic (the predominant one), gallic, and p-coumaric acids, were identified. Flavonoids, namely, (+)-catechin, (-)-epicatechin, and epigallocatechin, were also identified, and their contents increased with increasing temperature. The results so obtained suggest that HT-short time (HTST) roasting effectively enhances the antioxidant activity of cashew nuts and testa.
A Review of Rock Bolt Monitoring Using Smart Sensors.
Song, Gangbing; Li, Weijie; Wang, Bo; Ho, Siu Chun Michael
2017-04-05
Rock bolts have been widely used as rock reinforcing members in underground coal mine roadways and tunnels. Failures of rock bolts occur as a result of overloading, corrosion, seismic burst and bad grouting, leading to catastrophic economic and personnel losses. Monitoring the health condition of the rock bolts plays an important role in ensuring the safe operation of underground mines. This work presents a brief introduction on the types of rock bolts followed by a comprehensive review of rock bolt monitoring using smart sensors. Smart sensors that are used to assess rock bolt integrity are reviewed to provide a firm perception of the application of smart sensors for enhanced performance and reliability of rock bolts. The most widely used smart sensors for rock bolt monitoring are the piezoelectric sensors and the fiber optic sensors. The methodologies and principles of these smart sensors are reviewed from the point of view of rock bolt integrity monitoring. The applications of smart sensors in monitoring the critical status of rock bolts, such as the axial force, corrosion occurrence, grout quality and resin delamination, are highlighted. In addition, several prototypes or commercially available smart rock bolt devices are also introduced.
A Review of Rock Bolt Monitoring Using Smart Sensors
Song, Gangbing; Li, Weijie; Wang, Bo; Ho, Siu Chun Michael
2017-01-01
Rock bolts have been widely used as rock reinforcing members in underground coal mine roadways and tunnels. Failures of rock bolts occur as a result of overloading, corrosion, seismic burst and bad grouting, leading to catastrophic economic and personnel losses. Monitoring the health condition of the rock bolts plays an important role in ensuring the safe operation of underground mines. This work presents a brief introduction on the types of rock bolts followed by a comprehensive review of rock bolt monitoring using smart sensors. Smart sensors that are used to assess rock bolt integrity are reviewed to provide a firm perception of the application of smart sensors for enhanced performance and reliability of rock bolts. The most widely used smart sensors for rock bolt monitoring are the piezoelectric sensors and the fiber optic sensors. The methodologies and principles of these smart sensors are reviewed from the point of view of rock bolt integrity monitoring. The applications of smart sensors in monitoring the critical status of rock bolts, such as the axial force, corrosion occurrence, grout quality and resin delamination, are highlighted. In addition, several prototypes or commercially available smart rock bolt devices are also introduced. PMID:28379167
Power consumption and lumber yields for reduced-kerf circular saws cutting hardwoods
Donald G. Cuppett
1982-01-01
Two 50-inch diameter headsaws were used for sawing (a) hardwood cants into boards, and (b) hardwood bolts into pallet parts. One saw had a 9x10 gage plate with 114-inch kerf teeth, and the other had a 7x8 gage plate with 9/32-inch kerf teeth. Power consumption for the two saws was determined with a watt-hour meter, measuring power used for paired cuts in 6-inch thick...
26. View, looking east, of motor house; the electric motor ...
26. View, looking east, of motor house; the electric motor and electric-powered winch are housed in section of building to the left. The U-bolt and concrete deadman which anchors the cable of the tramway is to the right. Photo by Jet Lowe, HAER, 1989. - Puget Sound Power & Light Company, White River Hydroelectric Project, 600 North River Avenue, Dieringer, Pierce County, WA
External Tank (ET) Bipod Fitting Bolted Attachment Locking Insert Performance
NASA Technical Reports Server (NTRS)
Larsen, Curtis E.; Wilson, Tim R.; Elliott, Kenny B.; Raju, Ivatury S.; McManamen, John
2008-01-01
Following STS-107, the External Tank (ET) Project implemented corrective actions and configuration changes at the ET bipod fitting. Among the corrective actions, the existing bolt lock wire which provided resistance to potential bolt rotation was removed. The lock wire removal was because of concerns with creating voids during foam application and potential for lock wire to become debris. The bolts had been previously lubricated to facilitate assembly but, because of elimination of the lock wire, the ET Project wanted to enable the locking feature of the insert. Thus, the lubrication was removed from bolt threads and instead applied to the washer under the bolt head. Lubrication is necessary to maximize joint pre-load while remaining within the bolt torque specification. The locking feature is implemented by thread crimping in at four places in the insert. As the bolt is torqued into the insert the bolt threads its way past the crimped parts of the insert. This provides the locking of the bolt, as torque is required to loosen the joint after clamping.
Preload Monitoring of Bolted L-Shaped Lap Joints Using Virtual Time Reversal Method.
Du, Fei; Xu, Chao; Wu, Guannan; Zhang, Jie
2018-06-13
L-shaped bolt lap joints are commonly used in aerospace and civil structures. However, bolt joints are frequently subjected to loosening, and this has a significant effect on the safety and reliability of these structures. Therefore, bolt preload monitoring is very important, especially at the early stage of loosening. In this paper, a virtual time reversal guided wave method is presented to monitor preload of bolted L-shaped lap joints accurately and simply. In this method, a referenced reemitting signal (RRS) is extracted from the bolted structure in fully tightened condition. Then the RRS is utilized as the excitation signal for the bolted structure in loosening states, and the normalized peak amplitude of refocused wave packet is used as the tightness index (TI A ). The proposed method is experimentally validated by L-shaped bolt joints with single and multiple bolts. Moreover, the selections of guided wave frequency and tightness index are also discussed. The results demonstrate that the relationship between TI A and bolt preload is linear. The detection sensitivity is improved significantly compared with time reversal (TR) method, particularly when bolt loosening is at its embryo stage. The results also show that TR method is an effective method for detection of the number of loosening bolts.
Stress analysis of bolted joints under centrifugal force
NASA Astrophysics Data System (ADS)
Imura, Makoto; Iizuka, Motonobu; Nakae, Shigeki; Mori, Takeshi; Koyama, Takayuki
2014-06-01
Our objective is to develop a long-life rotary machine for synchronous generators and motors. To do this, it is necessary to design a high-strength bolted joint, which is responsible for fixing a salient pole on a rotor shaft. While the rotary machine is in operation, not only centrifugal force but also moment are loaded on a bolted joint, because a point of load is eccentric to a centre of a bolt. We tried to apply the theory proposed in VDI2230-Blatt1 to evaluate the bolted joint under eccentric force, estimate limited centrifugal force, which is the cause of partial separation between the pole and the rotor shaft, and then evaluate additional tension of a bolt after the partial separation has occurred. We analyzed the bolted joint by FEM, and defined load introduction factor in that case. Additionally, we investigated the effect of the variation of bolt preload on the partial separation. We did a full scale experiment with a prototype rotor to reveal the variation of bolt preload against tightening torque. After that, we verified limited centrifugal force and the strength of the bolted joint by the VDI2230-Blatt1 theory and FEM considering the variation of bolt preload. Finally, we could design a high-strength bolted joint verified by the theoretical study and FEM analysis.
Development of a Unified Rock Bolt Model in Discontinuous Deformation Analysis
NASA Astrophysics Data System (ADS)
He, L.; An, X. M.; Zhao, X. B.; Zhao, Z. Y.; Zhao, J.
2018-03-01
In this paper, a unified rock bolt model is proposed and incorporated into the two-dimensional discontinuous deformation analysis. In the model, the bolt shank is discretized into a finite number of (modified) Euler-Bernoulli beam elements with the degrees of freedom represented at the end nodes, while the face plate is treated as solid blocks. The rock mass and the bolt shank deform independently, but interact with each other through a few anchored points. The interactions between the rock mass and the face plate are handled via general contact algorithm. Different types of rock bolts (e.g., Expansion Shell, fully grouted rebar, Split Set, cone bolt, Roofex, Garford and D-bolt) can be realized by specifying the corresponding constitutive model for the tangential behavior of the anchored points. Four failure modes, namely tensile failure and shear failure of the bolt shank, debonding along the bolt/rock interface and loss of the face plate, are available in the analysis procedure. The performance of a typical conventional rock bolt (fully grouted rebar) and a typical energy-absorbing rock bolt (D-bolt) under the scenarios of suspending loosened blocks and rock dilation is investigated using the proposed model. The reliability of the proposed model is verified by comparing the simulation results with theoretical predictions and experimental observations. The proposed model could be used to reveal the mechanism of each type of rock bolt in realistic scenarios and to provide a numerical way for presenting the detailed profile about the behavior of bolts, in particular at intermediate loading stages.
Nondestructive test method accurately sorts mixed bolts
NASA Technical Reports Server (NTRS)
Dezeih, C. J.
1966-01-01
Neutron activation analysis method sorts copper plated steel bolts from nickel plated steel bolts. Copper and nickel plated steel bolt specimens of the same configuration are irradiated with thermal neutrons in a test reactor for a short time. After thermal neutron irradiation, the bolts are analyzed using scintillation energy readout equipment.
19 CFR 10.58 - Bolting cloths; marking.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 19 Customs Duties 1 2010-04-01 2010-04-01 false Bolting cloths; marking. 10.58 Section 10.58... TREASURY ARTICLES CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. General Provisions Bolting Cloths § 10.58 Bolting cloths; marking. (a) As a prerequisite to the free entry of bolting cloth for milling...
19 CFR 10.58 - Bolting cloths; marking.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 19 Customs Duties 1 2011-04-01 2011-04-01 false Bolting cloths; marking. 10.58 Section 10.58... TREASURY ARTICLES CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. General Provisions Bolting Cloths § 10.58 Bolting cloths; marking. (a) As a prerequisite to the free entry of bolting cloth for milling...
19 CFR 10.58 - Bolting cloths; marking.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 19 Customs Duties 1 2012-04-01 2012-04-01 false Bolting cloths; marking. 10.58 Section 10.58... TREASURY ARTICLES CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. General Provisions Bolting Cloths § 10.58 Bolting cloths; marking. (a) As a prerequisite to the free entry of bolting cloth for milling...
19 CFR 10.58 - Bolting cloths; marking.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 19 Customs Duties 1 2014-04-01 2014-04-01 false Bolting cloths; marking. 10.58 Section 10.58... TREASURY ARTICLES CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. General Provisions Bolting Cloths § 10.58 Bolting cloths; marking. (a) As a prerequisite to the free entry of bolting cloth for milling...
19 CFR 10.58 - Bolting cloths; marking.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 19 Customs Duties 1 2013-04-01 2013-04-01 false Bolting cloths; marking. 10.58 Section 10.58... TREASURY ARTICLES CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. General Provisions Bolting Cloths § 10.58 Bolting cloths; marking. (a) As a prerequisite to the free entry of bolting cloth for milling...
High-strength bolt corrosion fatigue life model and application.
Hui-li, Wang; Si-feng, Qin
2014-01-01
The corrosion fatigue performance of high-strength bolt was studied. Based on the fracture mechanics theory and the Gerberich-Chen formula, the high-strength bolt corrosion fracture crack model and the fatigue life model were established. The high-strength bolt crack depth and the fatigue life under corrosion environment were quantitatively analyzed. The factors affecting high-strength bolt corrosion fatigue life were discussed. The result showed that the high-strength bolt corrosion fracture biggest crack depth reduces along with the material yield strength and the applied stress increases. The material yield strength was the major factor. And the high-strength bolt corrosion fatigue life reduced along with the increase of material strength, the applied stress or stress amplitude. The stress amplitude influenced the most, and the material yield strength influenced the least. Low bolt strength and a low stress amplitude level could extend high-strength bolt corrosion fatigue life.
Analysis of alternatives for using cable bolts as primary support at two low-seam coal mines
Esterhuizen, Gabriel S.; Tulu, Ihsan B.
2016-01-01
Cable bolts are sometimes used in low-seam coal mines to provide support in difficult ground conditions. This paper describes cable bolting solutions at two low-seam coal mines in similar ground conditions. Both mines used support systems incorporating cable bolts as part of the primary support system. Two original cable bolt based support systems as well as two modified systems are evaluated to estimate their ability to prevent large roof falls. One of the support systems incorporated passive cable bolts, while the other used pre-tensioned cable bolts. The results and experience at the mines showed that the modified systems provided improved stability over the original support systems. The presence of the cable bolts is the most important contribution to stability against large roof falls, rather than the details of the support pattern. It was also found that a heavy steel channel can improve the safety of the system because of the ‘sling’ action it provides. Additionally, the analysis showed that fully-grouted rebar bolts load much earlier than the cable bolts, and pre-tensioning of the cable bolts can result in a more uniform distribution of loading in the roof. PMID:27722019
Analytical Study of the Mechanical Behavior of Fully Grouted Bolts in Bedding Rock Slopes
NASA Astrophysics Data System (ADS)
Liu, C. H.; Li, Y. Z.
2017-09-01
Bolting is widely used as a reinforcement means for rock slopes. The support force of a fully grouted bolt is often provided by the combination of the axial and shear forces acting at the cross section of the bolt, especially for bedding rock slopes. In this paper, load distribution and deformation behavior of the deflecting section of a fully grouted bolt were analyzed, and a structural mechanical model was established. Based on force method equations and deformation compatibility relationships, an analytical approach, describing the contribution of the axial and shear forces acting at the intersection between the bolt and the joint plane to the stability of a rock slope, was developed. Influence of the inclination of the bolt to the joint plane was discussed. Laboratory tests were conducted with different inclinations of the bolt to the joint plane. Comparisons between the proposed approach, the experimental data and a code method were made. The calculation results are in good agreement with the test data. It is shown that transverse shear resistance plays a significant role to the bolting contribution and that the bigger the dip of the bolt to the joint plane, the more significant the dowel effect. It is also shown that the design method suggested in the code overestimates the resistance of the bolt. The proposed model considering dowel effect provides a more precise description on bolting properties of bedding rock slopes than the code method and will be helpful to improve bolting design methods.
29 CFR 1917.118 - Fixed ladders.
Code of Federal Regulations, 2011 CFR
2011-07-01
... bolts or structural members of tanks and towers; (3) Ladders built into or vertically attached to..., microwave communications, electrical power and similar towers, poles and structures, including stacks and... consisting of individual rungs that are attached to walls, conical manhole sections or river cells shall: (1...
29 CFR 1917.118 - Fixed ladders.
Code of Federal Regulations, 2010 CFR
2010-07-01
... bolts or structural members of tanks and towers; (3) Ladders built into or vertically attached to..., microwave communications, electrical power and similar towers, poles and structures, including stacks and... consisting of individual rungs that are attached to walls, conical manhole sections or river cells shall: (1...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
Making self-assessment a ``cultural norm`` at the DOE Office of Energy Research (ER) laboratories has been a tremendous challenge. In an effort to provide a forum for the ER laboratories to share their self-assessment program implementation experiences, the Lawrence Berkeley Laboratory hosted a Self-Assessment Workshop: July 1993. The workshop was organized to cover such areas as: DOE`s vision of self-assessment; what makes a workable program; line management experiences; how to identify root causes and trends; integrating quality assurance, conduct of operations, and self-assessment; and going beyond environment, safety, and health. Individuals from the ER laboratories wishing to participate in themore » workshop were invited to speak on topics of their choice. The workshop was organized to cover general topics in morning presentations to all attendees and to cover selected topics at afternoon breakout sessions. This report summarizes the presentations and breakout discussions.« less
New Insights Into âPlant Memoriesâ
Sanbonmatsu, Karissa
2018-01-16
A special stretch of ribonucleic acid (RNA) called COOLAIR is revealing its inner structure and function to scientists, displaying a striking resemblance to an RNA molecular machine, territory previously understood to be limited to the cellsâ protein factory (the âribosomeâ) and not a skill set given to mere strings of RNA. âWe are uncovering the nuts and bolts of plant memories,â said Karissa Sanbonmatsu of Los Alamos National Laboratory, lead author on a new article this week in the journal Cell Reports. In the past 5 years or so, material in the cell known as âjunk DNAâ had actually turned out not to be junk at all. Instead, it was shown to produce RNA molecules that play key roles in the development of organs in the embryo, as well as affecting cancer, brain function and plant biology.
Ab initio study of edge effect on relative motion of walls in carbon nanotubes
NASA Astrophysics Data System (ADS)
Popov, Andrey M.; Lebedeva, Irina V.; Knizhnik, Andrey A.; Lozovik, Yurii E.; Potapkin, Boris V.
2013-01-01
Interwall interaction energies of double-walled nanotubes with long inner and short outer walls are calculated as functions of coordinates describing relative rotation and displacement of the walls using van der Waals corrected density functional theory. The magnitude of corrugation and the shape of the potential energy relief are found to be very sensitive to changes of the shorter wall length at subnanometer scale and atomic structure of the edges if at least one of the walls is chiral. Threshold forces required to start relative motion of the short walls and temperatures at which the transition between diffusive and free motion of the short walls takes place are estimated. The edges are also shown to provide a considerable contribution to the barrier to relative rotation of commensurate nonchiral walls. For such walls, temperatures of orientational melting, i.e., the crossover from rotational diffusion to free relative rotation, are estimated. The possibility to produce nanotube-based bolt/nut pairs and nanobearings is discussed.
Drag coefficients for loose reactor parts
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shi, L.; Doster, J.M.; Mayo, C.W.
1997-12-01
Loose-part monitoring systems are capable of providing estimates of loose-part mass and energy as well as impact location. Additional information regarding potentially damaging loose parts can be obtained by estimating loose-part velocity on the basis of free motion dynamics within the flow. To estimate the loose-part velocity, the drag coefficient of the part must be known. Traditionally, drag coefficients of three-dimensional bodies are measured in wind tunnels, by towing in free air or liquids, and with drop tests. These methods have disadvantages with respect to measuring drag coefficients for loose parts in that they require a fixed orientation, or themore » flow field is inconsistent with the turbulent flow conditions found in reactor systems. Though drag coefficients for some regularly shaped objects can be found in the literature, many shapes representative of typical loose parts have not been investigated. In this work, drag coefficients are measured for typical loose-part shapes, including bolts, nuts, pins, and hand tools within the flow conditions expected in reactor coolant systems.« less
What's Manifest in the History of SciTech: Reflections on The History Manifesto.
Kevles, Daniel J
2016-06-01
Making nuts-and-bolts public policy is not--and never has been--the long suit of professional historians, but general historical work, whatever its durée, has done a good deal to shape discourse on public issues. Jo Guldi and David Armitage neglect that fact, as well as the opinion-shaping influence of history conveyed via nonprint media. They also ignore the large body of scholarship produced in all media during recent decades in the history of science, technology, and science-related medicine (SciTech), even though SciTech itself looms enormously large in the modern era as an instrument of national and international security, a driver of the economy, and a transformer of medicine, public health, and the environment. Much of this scholarship, even though of short durée, can illuminate salient contemporary issues, including innovation; patronage and practice; government and policy; imperialism and globalization; intellectual property; science and religion; and human rights, environment, energy, and disasters.
A new design concept of fully grouted rock bolts in underground construction
NASA Astrophysics Data System (ADS)
Phich Nguyen, Quang; Nguyen, Van Manh; Tuong Nguyen, Ke
2018-04-01
The main problem after excavating an underground excavation is to maintain the stability of the excavation for a certain period of time. Failure in meeting this demand is a threat to safety of men and equipment. Support and reinforcement are different instruments with different mechanisms. Among the common support systems in tunnelling and mining, rock bolts have been widely used to reinforce rock mass and also to reduce geological hazards. Furthermore rock bolts can be applied under varying different geological conditions with cost-effectiveness. Although different methods are developed for grouted rock bolts design until now, the interaction mechanism of the rock bolts and rock mass is still very complicated issue. The paper addresses an analytical model for the analysis and design of fully grouted rock bolts based on the reinforcement principle. According to this concept the jointed rock mass reinforced by grouted rock bolts is considered as composite material which includes rock mass, the grout material and the bolt shank. The mechanical properties of this composite material depend on the ratio of the components. The closed-form solution was developed based on the assumption that the rock mass arround a circular tunnel remained elastic after installing fully grouted rock bolts. The main parameters of the rock-bolt system (the diameter and length of bolt shank, the space between the bolts) are then easily estimated from the obtained solution.
49 CFR 571.209 - Standard No. 209; Seat belt assemblies.
Code of Federal Regulations, 2010 CFR
2010-10-01
.... (1) Eye bolts, shoulder bolts, or other bolt used to secure the pelvic restraint of seat belt... connecting webbing to an eye bolt shall be provided with a retaining latch or keeper which shall not move...) Single attachment hook for connecting webbing to any eye bolt shall be tested in the following manner...
Ultrasonic measurement and monitoring of loads in bolts used in structural joints
NASA Astrophysics Data System (ADS)
Koshti, Ajay M.
2015-04-01
The paper is an overview of work by the author in measuring and monitoring loads in bolts using an ultrasonic extensometer. A number of cases of bolted joints are covered. These include, a clamped joint with clearance fit between the bolt and hole, a clamped joint with bolt in an interference fit with the hole, a flanged joint which allows the flange and bolt to bend; and a shear joint in a clevis and tang configuration. These applications were initially developed for measuring and monitoring preload in National Aeronautics and Space Administration (NASA) Space Shuttle Orbiter critical joints but are also applicable for monitoring loads in other critical bolted joints of structures such as transportation bridges and other aerospace structures. The papers cited here explain how to set-up a model to estimate the ultrasonic load factor and accuracy for the ultrasonic preload application in a clamped joint with clearance fit. The ultrasonic preload application for clamped joint with bolt in an interference fit can also be used to measure diametrical interference between the bolt shank and hole, as well as interference pressure on the bolt shank. Results of simulation and experimental data are given to demonstrate use of ultrasonic measurements in a shear joint. A bolt in a flanged joint experiences both tensile and bending loads. This application involves measurement of bending and tensile preload in a bolt. The ultrasonic beam bends due to bending load on the bolt. Results of a numerical technique to compute the trace of ultrasonic ray are presented.
Designing berthing mechanisms for international compatibility
NASA Technical Reports Server (NTRS)
Winch, John; Gonzalez-Vallejo, Juan J.
1991-01-01
The paper examines the technological issues regarding common berthing interfaces for the Space Station Freedom and pressurized modules from U.S., European, and Japanese space programs. The development of the common berthing mechanism (CBM) is based on common requirements concerning specifications, launch environments, and the unique requirements of ESA's Man-Tended Free Flyer. The berthing mechanism is composed of an active and a passive half, a remote manipulator system, 4 capture-latch assemblies, 16 structural bolts, and a pressure gage to verify equalization. Extensive graphic and verbal descriptions of each element are presented emphasizing the capture-latch motion and powered-bolt operation. The support systems to complete the interface are listed, and the manufacturing requirements for consistent fabrication are discussed to ensure effective international development.
Feasibility of fiberglass-reinforced bolted wood connections
D. F. Windorski; L. A. Soltis; R. J. Ross
Bolted connections often fail by a shear plug or a splitting beneath the bolt caused by tension perpendicular-to-grain stresses as the bolt wedges its way through the wood. Preventing this type of failure would enhance the capacity and reliability of the bolted connection, thus increasing the overall integrity of a timber structure and enabling wood to compete...
21 CFR 137.280 - Bolted yellow corn meal.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Bolted yellow corn meal. 137.280 Section 137.280... Flours and Related Products § 137.280 Bolted yellow corn meal. Bolted yellow corn meal conforms to the definition and standard of identity prescribed by § 137.255 for bolted white corn meal except that cleaned...
21 CFR 137.280 - Bolted yellow corn meal.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Bolted yellow corn meal. 137.280 Section 137.280... Flours and Related Products § 137.280 Bolted yellow corn meal. Bolted yellow corn meal conforms to the definition and standard of identity prescribed by § 137.255 for bolted white corn meal except that cleaned...
Sonar Transducer Reliability Improvement Program (STRIP) FY80.
1980-07-01
heating element powered by a temperature conLroller (YSI model 74) with a series 400 thermistor probe. Figure 3.1 shows the data and average curves...ATTACHMENT METHODS General Welded Receptacles Threaded or Bolted Receptacles Elastomeric Bonded Receptacles I I!11 " SECTION 12 - CABLE HARNESS TEST
Federal Register 2010, 2011, 2012, 2013, 2014
2013-08-19
... would remain deployed for 5 years and would be completely removed (including bolts and power sources) at... knowledge on the mechanics and pace of glacial retreat. Images gained from the cameras would also be used in...
NASA Astrophysics Data System (ADS)
Chen, Jinzhong; He, Renyang; Kang, Xiaowei; Yang, Xuyun
2015-10-01
The non-destructive testing of small-sized (M12-M20) stainless steel bolts in servicing is always a technical problem. This article focuses on the simulation and experimental research of stainless steel bolts with an artificial defect reflector using ultrasonic phased array inspection. Based on the observation of the sound field distribution of stainless steel bolts in ultrasonic phased array as well as simulation modelling and analysis of the phased array probes' detection effects with various defect sizes, different artificial defect reflectors of M16 stainless steel bolts are machined in reference to the simulation results. Next, those bolts are tested using a 10-wafer phased array probe with 5 MHz. The test results finally prove that ultrasonic phased array can detect 1-mm cracks in diameter with different depths of M16 stainless steel bolts and a metal loss of Φ1 mm of through-hole bolts, which provides technical support for future non-destructive testing of stainless steel bolts in servicing.
Sutton, Jr., Harry G.
1984-01-01
Bolts of a liquid metal fast breeder reactor, each bolt provided with an internal chamber filled with a specific, unique radioactive tag gas. Detection of the tag gas is indicative of a crack in an identifiable bolt.
NASA Astrophysics Data System (ADS)
Zhang, Zhen; Liu, Menglong; Liao, Yaozhong; Su, Zhongqing; Xiao, Yi
2018-03-01
The significance of evaluating bolt tightness in engineering structures, preferably in a continuous manner, cannot be overemphasized. With hybrid use of high-order harmonics (HOH) and spectral sidebands, a contact acoustic nonlinearity (CAN)-based monitoring framework is developed for detecting bolt loosening and subsequently evaluating the residual torque on a loose bolt. Low-frequency pumping vibration is introduced into the bolted joint to produce a "breathing" effect at the joining interface that modulates the propagation characteristics of a high-frequency probing wave when it traverses the bolt, leading to the generation of HOH and vibro-acoustic nonlinear distortions (manifested as sidebands in the signal spectrum). To gain insight into the mechanism of CAN generation and to correlate the acquired nonlinear responses of a loose joint with the residual torque remaining on the bolt, an analytical model based on micro-contact theory is established. Two types of nonlinear index, respectively exploiting the induced HOH and spectral sidebands, are defined without dependence on excitation intensity and are experimentally demonstrated to be effective in continuously monitoring bolt loosening in both aluminum-aluminum and composite-composite bolted joints. Taking a step further, variation of the index pair is quantitatively associated with the residual torque on a loose bolt. The approach developed provides a reliable method of continuous evaluation of bolt tightness in both composite and metallic joints, regardless of their working conditions, from early awareness of bolt loosening at an embryonic stage to quantitative estimation of residual torque.
Griffin, Xavier L; Achten, Juul; Sones, William; Cook, Jonathan; Costa, Matthew L
2018-01-26
Sliding hip screw fixation is well established in the treatment of trochanteric fractures of the hip. The X-Bolt Dynamic Hip Plating System builds on the successful design features of the sliding hip screw but differs in the nature of the fixation in the femoral head. A randomised pilot study suggested that the X-bolt Dynamic Hip Plating System might provide similar health-related quality of life while reducing the risk of revision surgery when compared with the sliding hip screw. This is the protocol for a multicentre randomised trial of sliding hip screw versus X-Bolt Dynamic Hip Plating System for patients 60 years and over treated for a trochanteric fracture of the hip. Multicentre, multisurgeon, parallel, two-arm, randomised controlled trial. Patients aged 60 years and older with a trochanteric hip fracture are potentially eligible. Participants will be randomly allocated on a 1:1 basis to either sliding hip screw or X-Bolt Dynamic Hip Plating System. Otherwise, all care will be in accordance with National Institute for Health and Care Excellence guidance. A minimum of 1128 patients will be recruited to obtain 90% power to detect a 0.075-point difference in EuroQol-5D health-related quality of life at 4 months postrandomisation. Secondary outcomes include mortality, residential status, revision surgery and radiographic measures. The treatment effect will be estimated using a two-sided t-test adjusted for age, gender and cognitive impairment based on an intention-to-treat analysis. National Research Ethics Committee approved this study on 5 February 2016 (16/WM/0001). The study is sponsored by the University of Oxford and funded through an investigator initiated grant by X-Bolt Orthopaedics. A manuscript for a high-impact peer-reviewed journal will be prepared, and the results will be disseminated to patients through local mechanisms at participating centres. ISRCTN92825709. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
A Modelling Method of Bolt Joints Based on Basic Characteristic Parameters of Joint Surfaces
NASA Astrophysics Data System (ADS)
Yuansheng, Li; Guangpeng, Zhang; Zhen, Zhang; Ping, Wang
2018-02-01
Bolt joints are common in machine tools and have a direct impact on the overall performance of the tools. Therefore, the understanding of bolt joint characteristics is essential for improving machine design and assembly. Firstly, According to the experimental data obtained from the experiment, the stiffness curve formula was fitted. Secondly, a finite element model of unit bolt joints such as bolt flange joints, bolt head joints, and thread joints was constructed, and lastly the stiffness parameters of joint surfaces were implemented in the model by the secondary development of ABAQUS. The finite element model of the bolt joint established by this method can simulate the contact state very well.
Failure Analysis on Tail Rotor Teeter Pivot Bolt on a Helicopter
NASA Astrophysics Data System (ADS)
Qiang, WANG; Zi-long, DONG
2018-03-01
Tail rotor teeter pivot bolt of a helicopter fractured when in one flight. Failure analysis on the bolt was finished in laboratory. Macroscopic observation of the tailor rotor teeter pivot bolt, macro and microscopic inspection on the fracture surface of the bolt was carried out. Chemical components and metallurgical structure was also carried out. Experiment results showed that fracture mode of the tail rotor teeter pivot bolt is fatigue fracture. Fatigue area is over 80% of the total fracture surface, obvious fatigue band characteristics can be found at the fracture face. According to the results were analyzed from the macroscopic and microcosmic aspects, fracture reasons of the tail rotor teeter pivot bolt were analyzed in detail
Effect of fiberglass reinforcement on the behavior of bolted wood connections
Lawrence A. Soltis; Robert J. Ross; Daniel E. Windorski
1997-01-01
Bolted connections often fail by a shear plug or by splitting beneath the bolt caused by tension perpendicular-to-grain stress as the bolt wedges its way through the wood. Preventing this type of failure enhances both the capacity and reliability of bolted connections. This research investigated the use of fiberglass reinforcement to enhance the load-carrying capacity...
The Fatigue Characteristics of Bolted Lap Joints of 24S-T Alclad Sheet Materials
1946-10-01
extremely close bolt fits are needed to o%tain maximum life of bolt ~oint~ under repeated etreseeci. -. Szvzral ty~+?+s of bolt patterns hava been tegted...Memorial Institute on spec~meris of 0.102-i.nch sheet. In particular, figure 4 shows, on a load- life diagram, . results of tests Qn single-bolt...results of tests at the Univer- sity of’ il~~nols on single—bolt specimens, Tables 10 and 11 give reeults of tests, made at the U“ uiversity of Illino~8 , on
Flexible roof drill for low coal. Volume 2. Phase III and Phase IV
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shoup, N.H.
1977-09-01
Design specifications were developed for a flexible drilling and bolting system. The system configuration is based on the use of the Galis dual-boom roof drill as a vehicle for the drilling/bolting system. The WSU Flex-drill drivehead is mounted on the Galis drill boom and the Galis parts are modified to accommodate the revised system. The flexible drillhead supports a bolt bender/inserter designed by Bendix Corporation and is integrated into the system operation. A supplemental bolt thruster was designed to complete insertion of the roof bolt following operation and removal of the Bendix bender from the bolt shank. The complete cyclemore » of drilling a 1-3/8-in. diameter bolt hole, bending a roof bolt into the hole, thrusting the bolt head and washer to the roof surface, and final torquing of the bolt is manually controlled by the operator located in the new position behind the bolting line. The new operating position is beneath newly bolted roof in a safer location in back of the stab jack ad roof jacks positioning the drill boom and drivehead. The Flex-drill/bolting system prototype was constructed from both purchased components and parts specially fabricated in the shops for this design. This unit was assembled and test-operated with appropriate support equipment in a laboratory test stand. Numerous test holes were drilled in blocks of concrete at feed rates of 5 ft/min with drill rotation speeds of 360 rpm. The drill feeds uniformly and cuts smoothly with no difficulty in collection of dust or clogging of the drill bit. The holes drilled were straight, as evidence by passage of a 1-1/4-in. diameter bar full depth into the hole with no binding or evidence of curvature. The flexible drill is capable of drilling 8-ft-deep roof bolt holes in low coal 36 in. in height.« less
A Novel RFID-Based Sensing Method for Low-Cost Bolt Loosening Monitoring.
Wu, Jian; Cui, Xingmei; Xu, Yunpeng
2016-01-28
In coal mines, bolt loosening in the cage guide is affected by the harsh environmental factors and cage hoist vibration, leading to significant threats to work safety. It is crucial, to this effect, to successfully detect the status of multipoint bolts of guide structures. This paper proposes a system to monitor bolt status in harsh environments established based on the RFID technique. A proof-of-concept model was demonstrated consisting of a bolt gearing system, passive UHF RFID tags, a reader, and monitoring software. A tinfoil metal film is fixed on the retaining plate and an RFID tag bonded to a large gear, with the bolt to be detected fixed in the center of a smaller gear. The radio-frequency signal cannot be received by the reader if the tag is completely obscured by the tinfoil, and if the bolt is loose, the tag's antenna is exposed when the gear revolves. A radio-frequency signal that carries corresponding bolt's information is transmitted by the RFID tag to the RFID reader due to coil coupling, identifying loose bolt location and reporting them in the software. Confirmatory test results revealed that the system indeed successfully detects bolt loosening and comparative test results (based on a reed switch multipoint bolt loosening monitor system) provided valuable information regarding the strengths and weaknesses of the proposed system.
Low profile, highly configurable, current sharing paralleled wide band gap power device power module
McPherson, Brice; Killeen, Peter D.; Lostetter, Alex; Shaw, Robert; Passmore, Brandon; Hornberger, Jared; Berry, Tony M
2016-08-23
A power module with multiple equalized parallel power paths supporting multiple parallel bare die power devices constructed with low inductance equalized current paths for even current sharing and clean switching events. Wide low profile power contacts provide low inductance, short current paths, and large conductor cross section area provides for massive current carrying. An internal gate & source kelvin interconnection substrate is provided with individual ballast resistors and simple bolted construction. Gate drive connectors are provided on either left or right size of the module. The module is configurable as half bridge, full bridge, common source, and common drain topologies.
6. View of turbine pit at unit 3 showing servomotor ...
6. View of turbine pit at unit 3 showing servo-motor head (left of center) with piston rods bolted to turbine gate operation ring (right foreground). View to southeast. - Holter Hydroelectric Facility, Dam & Power House, End of Holter Dam Road, Wolf Creek, Lewis and Clark County, MT
NASA Technical Reports Server (NTRS)
Mcdougal, A. R.; Norman, R. M. (Inventor)
1976-01-01
A gear head wrench particularly suited for use in applying torque to bolts without transferring torsional stress to bolt-receiving structures is introduced. The wrench is characterized by a coupling including a socket, for connecting a bolt head with a torque multiplying gear train, provided within a housing having an annulus concentrically related to the socket and adapted to be coupled with a spacer interposed between the bolt head and the juxtaposed surface of the bolt-receiving structure for applying a balancing counter-torque to the spacer as torque is applied to the bolt head whereby the bolt-receiving structure is substantially isolated from torsional stress. As a result of the foregoing, the operator of the wrench is substantially isolated from any forces which may be imposed.
Dimensional Analysis of Impulse Loading Resulting from Detonation of Shallow-Buried Charges
2013-01-01
lines running along the floor, floor-bolted seats , ammunition storage racks, power-train lines, etc.). MMMS 9,3 368 Traditionally, the floor-rupture...The power of dimensional analysis is that the functional relations offered are generalized, i.e. the effect of geometrical, kinematic , ambient, loading... ejected vdet Explosive detonation velocity L/T A new quantity added which controls the time of sand-overburden bubble burst Charge/plate positioning
Piezoelectric Bolt Breakers and Bolt Fatigue Testers
NASA Technical Reports Server (NTRS)
Sherrit, Stewart; Badescu, Mircea; Bar-Cohen, Yoseph; Barengoltz, Jack; Heckman, Vanessa
2008-01-01
A proposed family of devices for inducing fatigue in bolts in order to break the bolts would incorporate piezoelectric actuators into resonant fixtures as in ultrasonic/ sonic drills/corers and similar devices described in numerous prior NASA Tech Briefs articles. These devices were originally intended primarily for use as safer, more-reliable, more-versatile alternatives to explosive bolts heretofore used to fasten spacecraft structures that must subsequently be separated from each other quickly on command during flight. On Earth, these devices could be used for accelerated fatigue testing of bolts. Fatigue theory suggests that a bolt subjected to both a constant-amplitude dynamic (that is, oscillatory) stress and a static tensile stress below the ultimate strength of the bolt material will fail faster than will a bolt subjected to only the dynamic stress. This suggestion would be applied in a device of the proposed type. The device would be designed so that the device and the bolt to be fatigue-tested or broken would be integral parts of an assembly (see figure). The static tension in the tightened bolt would apply not only the clamping force to hold the joined structures (if any) together but also the compression necessary for proper operation of the piezoelectric actuators as parts of a resonant structural assembly. The constant-amplitude dynamic stress would be applied to the bolt by driving the piezoelectric actuators with a sinusoidal voltage at the resonance frequency of longitudinal vibration of the assembly. The amplitude of the excitation would be made large enough so that the vibration would induce fatigue in the bolt within an acceptably short time. In the spacecraft applications or in similar terrestrial structural-separation applications, devices of the proposed type would offer several advantages over explosive bolts: Unlike explosive bolts, the proposed devices would be reusable, could be tested before final use, and would not be subject to catastrophic misfire. In fatigue-testing applications, devices of the proposed type would offer advantages of compactness and low cost, relative to conventional fatigue- testing apparatuses. In both structural- separation and fatigue-testing applications, bolts to be broken or tested could be instrumented with additional ultrasonic transducers for monitoring of pertinent physical properties and of fatigue failure processes.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 7 Agriculture 8 2012-01-01 2012-01-01 false Powers. 920.30 Section 920.30 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE KIWIFRUIT GROWN IN CALIFORNIA Administrative...
Code of Federal Regulations, 2013 CFR
2013-01-01
... 7 Agriculture 8 2013-01-01 2013-01-01 false Powers. 920.30 Section 920.30 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE KIWIFRUIT GROWN IN CALIFORNIA Administrative...
Code of Federal Regulations, 2011 CFR
2011-01-01
... 7 Agriculture 8 2011-01-01 2011-01-01 false Powers. 920.30 Section 920.30 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE KIWIFRUIT GROWN IN CALIFORNIA Administrative...
Code of Federal Regulations, 2014 CFR
2014-01-01
... 7 Agriculture 8 2014-01-01 2014-01-01 false Powers. 920.30 Section 920.30 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE KIWIFRUIT GROWN IN CALIFORNIA Administrative...
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 8 2010-01-01 2010-01-01 false Powers. 920.30 Section 920.30 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE KIWIFRUIT GROWN IN CALIFORNIA Administrative...
Wang, Bo; Huo, Linsheng; Chen, Dongdong; Li, Weijie; Song, Gangbing
2017-01-27
Pre-stress degradation or looseness of rock bolts in mining or tunnel engineering threatens the stability and reliability of the structures. In this paper, an innovative piezoelectric device named a "smart washer" with the impedance method is proposed with the aim of developing a real-time device to monitor the pre-stress level of rock bolts. The proposed method was verified through tests on a rock bolt specimen. By applying high-frequency sweep excitations (typically >30 kHz) to the smart washer that was installed on the rock bolt specimen, we observed that the variation in impedance signatures indicated the rock bolt pre-stress status. With the degradation of rock bolt pre-stress, the frequency in the dominating peak of the real part of the electrical impedance signature increased. To quantify the effectiveness of the proposed technique, a normalized root mean square deviation (RMSD) index was developed to evaluate the degradation level of the rock bolt pre-stress. The experimental results demonstrated that the normalized RMSD-based looseness index, which was computed from the impedance value detected by the "smart washer", increased with loss of the pre-stress of the rock bolt. Therefore, the proposed method can effectively detect the degradation of rock bolt pre-stress, as demonstrated by experiments.
Study on the Optimal Groove Shape and Glue Material for Fiber Bragg Grating Measuring Bolts.
Zhao, Yiming; Zhang, Nong; Si, Guangyao; Li, Xuehua
2018-06-02
Fiber Bragg grating (FBG) measuring bolts, as a useful tool to evaluate the behaviors of steel bolts in underground engineering, can be manufactured by gluing the FBG sensors inside the grooves, which are usually symmetrical cuts along the steel bolt rod. The selection of the cut shape and the glue types could perceivably affect the final supporting strength of the bolts. Unfortunately, the impact of cut shape and glue type on bolting strength is not yet clear. In this study, based on direct tension tests, full tensile load⁻displacement curves of rock bolts with different groove shapes were obtained and analyzed. The effects of groove shape on the bolt strength were discussed, and the stress redistribution in the cross-section of a rock bolt with different grooves was simulated using ANSYS. The results indicated that the trapezoidal groove is best for manufacturing the FBG bolt due to its low reduction of supporting strength. Four types of glues commonly used for the FBG sensors were assessed by conducting tensile tests on the mechanical testing and simulation system and the static and dynamic optical interrogators system. Using linear regression analysis, the relationship between the reflected wavelength of FBG sensors and tensile load was obtained. Practical recommendations for glue selection in engineering practice are also provided.
Image Registration-Based Bolt Loosening Detection of Steel Joints
2018-01-01
Self-loosening of bolts caused by repetitive loads and vibrations is one of the common defects that can weaken the structural integrity of bolted steel joints in civil structures. Many existing approaches for detecting loosening bolts are based on physical sensors and, hence, require extensive sensor deployment, which limit their abilities to cost-effectively detect loosened bolts in a large number of steel joints. Recently, computer vision-based structural health monitoring (SHM) technologies have demonstrated great potential for damage detection due to the benefits of being low cost, easy to deploy, and contactless. In this study, we propose a vision-based non-contact bolt loosening detection method that uses a consumer-grade digital camera. Two images of the monitored steel joint are first collected during different inspection periods and then aligned through two image registration processes. If the bolt experiences rotation between inspections, it will introduce differential features in the registration errors, serving as a good indicator for bolt loosening detection. The performance and robustness of this approach have been validated through a series of experimental investigations using three laboratory setups including a gusset plate on a cross frame, a column flange, and a girder web. The bolt loosening detection results are presented for easy interpretation such that informed decisions can be made about the detected loosened bolts. PMID:29597264
Mine roof driller-bolter apparatus and method
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hibbard, G.A.; Lumbra, R.C.; Morrison, W.D.
1983-12-13
An apparatus for bolting the roof of an underground mine is disclosed comprising a mobile frame, a boom extending from the frame and a housing provided at the end of the frame. The housing supports an upwardly extending stinger, a drilling mechanism including a drill centralizer having a central bore therethrough and a passageway in communication with the central bore, a device for delivering a container of roof bolting anchoring media through the passageway and through the drill centralizer and into a drilled hole, a device for indexing a roof bolt into alignment with the drilled hole and a spinnermore » for driving the roof bolt into the drilled hole. The present invention also provides a method for bolting the roof of an underground mine comprising the steps of stinging a housing against the roof of the mine, moving a drill centralizer into communication with the roof and drilling a hole in the roof. Without retracting the drill centralizer from communication with the roof, a container of roof bolt anchoring media is delivered through the centralizer and into the drilled hole. The drill centralizer is thereafter retracted and the housing is moved to align a roof bolt with a drilled hole. Then the roof bolt is driven into the drilled hole and the bolt anchoring media sets around the bolt.« less
Image Registration-Based Bolt Loosening Detection of Steel Joints.
Kong, Xiangxiong; Li, Jian
2018-03-28
Self-loosening of bolts caused by repetitive loads and vibrations is one of the common defects that can weaken the structural integrity of bolted steel joints in civil structures. Many existing approaches for detecting loosening bolts are based on physical sensors and, hence, require extensive sensor deployment, which limit their abilities to cost-effectively detect loosened bolts in a large number of steel joints. Recently, computer vision-based structural health monitoring (SHM) technologies have demonstrated great potential for damage detection due to the benefits of being low cost, easy to deploy, and contactless. In this study, we propose a vision-based non-contact bolt loosening detection method that uses a consumer-grade digital camera. Two images of the monitored steel joint are first collected during different inspection periods and then aligned through two image registration processes. If the bolt experiences rotation between inspections, it will introduce differential features in the registration errors, serving as a good indicator for bolt loosening detection. The performance and robustness of this approach have been validated through a series of experimental investigations using three laboratory setups including a gusset plate on a cross frame, a column flange, and a girder web. The bolt loosening detection results are presented for easy interpretation such that informed decisions can be made about the detected loosened bolts.
Wang, Bo; Huo, Linsheng; Chen, Dongdong; Li, Weijie; Song, Gangbing
2017-01-01
Pre-stress degradation or looseness of rock bolts in mining or tunnel engineering threatens the stability and reliability of the structures. In this paper, an innovative piezoelectric device named a “smart washer” with the impedance method is proposed with the aim of developing a real-time device to monitor the pre-stress level of rock bolts. The proposed method was verified through tests on a rock bolt specimen. By applying high-frequency sweep excitations (typically >30 kHz) to the smart washer that was installed on the rock bolt specimen, we observed that the variation in impedance signatures indicated the rock bolt pre-stress status. With the degradation of rock bolt pre-stress, the frequency in the dominating peak of the real part of the electrical impedance signature increased. To quantify the effectiveness of the proposed technique, a normalized root mean square deviation (RMSD) index was developed to evaluate the degradation level of the rock bolt pre-stress. The experimental results demonstrated that the normalized RMSD-based looseness index, which was computed from the impedance value detected by the “smart washer”, increased with loss of the pre-stress of the rock bolt. Therefore, the proposed method can effectively detect the degradation of rock bolt pre-stress, as demonstrated by experiments. PMID:28134811
NASA Technical Reports Server (NTRS)
1981-01-01
Ultrasonic P2L2 bolt monitor is a new industrial tool, developed at Langley Research Laboratory, which is lightweight, portable, extremely accurate because it is not subject to friction error, and it is cost-competitive with the least expensive of other types of accurate strain monitors. P2L2 is an acronym for Pulse Phase Locked Loop. The ultrasound system which measures the stress that occurs when a bolt becomes elongated in the process of tightening, transmits sound waves to the bolt being fastened and receives a return signal indicating changes in bolt stress. Results are translated into a digital reading of the actual stress on the bolt. Device monitors the bolt tensioning process on mine roof bolts that provide increased safety within the mine. Also has utility in industrial applications.
Damage Progression in Bolted Composites
NASA Technical Reports Server (NTRS)
Minnetyan, Levon; Chamis, Christos C.; Gotsis, Pascal K.
1998-01-01
Structural durability, damage tolerance, and progressive fracture characteristics of bolted graphite/epoxy composite laminates are evaluated via computational simulation. Constituent material properties and stress and strain limits are scaled up to the structure level to evaluate the overall damage and fracture propagation for bolted composites. Single and double bolted composite specimens with various widths and bolt spacings are evaluated. The effect of bolt spacing is investigated with regard to the structural durability of a bolted joint. Damage initiation, growth, accumulation, and propagation to fracture are included in the simulations. Results show the damage progression sequence and structural fracture resistance during different degradation stages. A procedure is outlined for the use of computational simulation data in the assessment of damage tolerance, determination of sensitive parameters affecting fracture, and interpretation of experimental results with insight for design decisions.
Damage Progression in Bolted Composites
NASA Technical Reports Server (NTRS)
Minnetyan, Levon; Chamis, Christos; Gotsis, Pascal K.
1998-01-01
Structural durability,damage tolerance,and progressive fracture characteristics of bolted graphite/epoxy composite laminates are evaluated via computational simulation. Constituent material properties and stress and strain limits are scaled up to the structure level to evaluate the overall damage and fracture propagation for bolted composites. Single and double bolted composite specimens with various widths and bolt spacings are evaluated. The effect of bolt spacing is investigated with regard to the structural durability of a bolted joint. Damage initiation, growth, accumulation, and propagation to fracture are included in the simulations. Results show the damage progression sequence and structural fracture resistance during different degradation stages. A procedure is outlined for the use of computational simulation data in the assessment of damage tolerance, determination of sensitive parameters affecting fracture, and interpretation of experimental results with insight for design decisions.
Amin, Muhammad Nasir; Zaheer, Salman; Alazba, Abdulrahman Ali; Saleem, Muhammad Umair; Niazi, Muhammad Umar Khan; Khurram, Nauman; Amin, Muhammad Tahir
2016-01-01
Structural hollow sections are gaining worldwide importance due to their structural and architectural advantages over open steel sections. The only obstacle to their use is their connection with other structural members. To overcome the obstacle of tightening the bolt from one side has given birth to the concept of blind bolts. Blind bolts, being the practical solution to the connection hindrance for the use of hollow and concrete filled hollow sections play a vital role. Flowdrill, the Huck High Strength Blind Bolt and the Lindapter Hollobolt are the well-known commercially available blind bolts. Although the development of blind bolts has largely resolved this issue, the use of structural hollow sections remains limited to shear resistance. Therefore, a new modified version of the blind bolt, known as the "Extended Hollo-Bolt" (EHB) due to its enhanced capacity for bonding with concrete, can overcome the issue of low moment resistance capacity associated with blind-bolted connections. The load transfer mechanism of this recently developed blind bolt remains unclear, however. This study uses a parametric approach to characterising the EHB, using diameter as the variable parameter. Stiffness and load-carrying capacity were evaluated at two different bolt sizes. To investigate the load transfer mechanism, a component-based study of the bond and anchorage characteristics was performed by breaking down the EHB into its components. The results of the study provide insight into the load transfer mechanism of the blind bolt in question. The proposed component-based model was validated by a spring model, through which the stiffness of the EHB was compared to that of its components combined. The combined stiffness of the components was found to be roughly equivalent to that of the EHB as a whole, validating the use of this component-based approach.
Natural frequency identification of smart washer by using adaptive observer
NASA Astrophysics Data System (ADS)
Ito, Hitoshi; Okugawa, Masayuki
2014-04-01
Bolted joints are used in many machines/structures and some of them have been loosened during long time use, and unluckily these bolt loosening may cause a great accident of machines/structures system. These bolted joint, especially in important places, are main object of maintenance inspection. Maintenance inspection with human- involvement is desired to be improved owing to time-consuming, labor-intensive and high-cost. By remote and full automation monitoring of the bolt loosening, constantly monitoring of bolted joint is achieved. In order to detect loosening of bolted joints without human-involvement, applying a structural health monitoring technique and smart structures/materials concept is the key objective. In this study, a new method of bolt loosening detection by adopting a smart washer has been proposed, and the basic detection principle was discussed with numerical analysis about frequency equation of the system, was confirmed experimentally. The smart washer used in this study is in cantilever type with piezoelectric material, which adds the washer the self-sensing and actuation function. The principle used to detect the loosening of the bolts is a method of a bolt loosening detection noted that the natural frequency of a smart washer system is decreasing by the change of the bolt tightening axial tension. The feature of this proposed method is achieving to identify the natural frequency at current condition on demand by adopting the self-sensing and actuation function and system identification algorithm for varying the natural frequency depending the bolt tightening axial tension. A novel bolt loosening detection method by adopting adaptive observer is proposed in this paper. The numerical simulations are performed to verify the possibility of the adaptive observer-based loosening detection. Improvement of the detection accuracy for a bolt loosening is confirmed by adopting initial parameter and variable adaptive gain by numerical simulation.
2013-01-01
Background Bolting reduces the quality and commercial yield of Welsh onion (Allium fistulosum L.) in production. However, seed production is directly dependent on flower induction and bolting. The Welsh onion belongs to the green plant vernalisation type, specific seedling characteristics and sufficient accumulated time at low temperature are indispensible for the completion of its vernalisation process. Only if these conditions for vernalisation are fulfilled, the plants will bolt in the following year. The present investigation evaluated the effects of cultivar, sowing date and transplant location in field on the bolting of Welsh onion at the Horticultural Farm of the College of Horticulture, Northwest A&F University, Yangling, Shannxi Province, China in two succeeding production years: 2010–2011 and 2011–2012. A strip split plot layout within a randomised complete block design with three replications was used. Results The results revealed that all three factors (cultivar, sowing date and transplant location) and their interaction had significant effects on the initiation and final rate of bolting observed by 30 April. The earliest bolting date (14 February, 2011 and 15 February, 2012) and the highest bolting rate (100% in 2011 and 62% in 2012) occurred when the JinGuan cultivar was sown on 20 August and transplanted in a plastic tunnel, whereas the latest date and lowest rate (no bolting observed until 30 April) of bolting occurred when the XiaHei cultivar was sown on 29 September and transplanted in an open field. Conclusions These results suggest that we can control bolting in Welsh onion production by choosing an appropriate cultivar, sowing date and transplant location. Choosing a late bolting cultivar, such as cultivar XiaHei, sowing around October, and transplanting in the open field can significantly delay bolting, while a sowing date in late August should be selected for seed production, and the seedlings should be transplanted in a plastic tunnel to accelerate development of the flower buds. PMID:24199907
Dong, Yinxin; Cheng, Zhihui; Meng, Huanwen; Liu, Hanqiang; Wu, Cuinan; Khan, Abdul Rehman
2013-10-07
Bolting reduces the quality and commercial yield of Welsh onion (Allium fistulosum L.) in production. However, seed production is directly dependent on flower induction and bolting. The Welsh onion belongs to the green plant vernalisation type, specific seedling characteristics and sufficient accumulated time at low temperature are indispensible for the completion of its vernalisation process. Only if these conditions for vernalisation are fulfilled, the plants will bolt in the following year. The present investigation evaluated the effects of cultivar, sowing date and transplant location in field on the bolting of Welsh onion at the Horticultural Farm of the College of Horticulture, Northwest A&F University, Yangling, Shannxi Province, China in two succeeding production years: 2010-2011 and 2011-2012. A strip split plot layout within a randomised complete block design with three replications was used. The results revealed that all three factors (cultivar, sowing date and transplant location) and their interaction had significant effects on the initiation and final rate of bolting observed by 30 April. The earliest bolting date (14 February, 2011 and 15 February, 2012) and the highest bolting rate (100% in 2011 and 62% in 2012) occurred when the JinGuan cultivar was sown on 20 August and transplanted in a plastic tunnel, whereas the latest date and lowest rate (no bolting observed until 30 April) of bolting occurred when the XiaHei cultivar was sown on 29 September and transplanted in an open field. These results suggest that we can control bolting in Welsh onion production by choosing an appropriate cultivar, sowing date and transplant location. Choosing a late bolting cultivar, such as cultivar XiaHei, sowing around October, and transplanting in the open field can significantly delay bolting, while a sowing date in late August should be selected for seed production, and the seedlings should be transplanted in a plastic tunnel to accelerate development of the flower buds.
Liu, Xueying; Lv, Shanshan; Liu, Ran; Fan, Shuangxi; Liu, Chaojie; Liu, Renyi; Han, Yingyan
2018-01-01
A cool temperature is preferred for lettuce cultivation, as high temperatures cause premature bolting. Accordingly, exploring the mechanism of bolting and preventing premature bolting is important for agriculture. To explore this relationship in depth, morphological, physiological, and transcriptomic analyses of the bolting-sensitive line S39 at the five-leaf stage grown at 37°C were performed in the present study. Based on paraffin section results, we observed that S39 began bolting on the seventh day at 37°C. During bolting in the heat-treated plants, GA3 and GA4 levels in leaves and the indoleacetic acid (IAA) level in the stem reached a maximum on the sixth day, and these high contents were maintained. Additionally, bolting begins in the fifth day after GA3 treatment in S39 plants, GA3 and GA4 increased and then decreased, reaching a maximum on the fourth day in leaves. Similarly, IAA contents reached a maximum in the stem on the fifth day. No bolting was observed in the control group grown at 25°C, and significant changes were not observed in GA3 and GA4 levels in the controls during the observation period. RNA-sequencing data implicated transcription factors (TFs) in regulating bolting in lettuce, suggesting that the high GA contents in the leaves and IAA in the stem promote bolting. TFs possibly modulate the expression of related genes, such as those encoding hormones, potentially regulating bolting in lettuce. Compared to the control group, 258 TFs were identified in the stem of the treatment group, among which 98 and 156 were differentially up- and down-regulated, respectively; in leaves, 202 and 115 TFs were differentially up- and down-regulated, respectively. Significant changes in the treated group were observed for C2H2 zinc finger, AP2-EREBP, and WRKY families, indicating that these TFs may play important roles in regulating bolting.
NASA Technical Reports Server (NTRS)
Crews, J. H., Jr.
1974-01-01
The stresses and strains in a uniaxially loaded sheet with an unloaded interference-fit bolt were calculated by an elastoplastic finite-element analysis. The material properties represented a 7075-T6 aluminum alloy sheet and a steel bolt. The analysis considered the two ideal cases of no slip and no friction at the bolt-sheet interface for a single combination of bolt diameter, interference level, and cyclic loading. When the bolt was inserted, the sheet deformed plastically near the hole; the first tensile load cycle produced additional yielding, but subsequent cycles to the same level caused only elastic cyclic stresses. These stresses together with fatigue data for unnotched specimens were used to estimate crack initiation periods and initiation sites. The cases analyzed with interference-fit bolts were predicted to have crack initiation periods which were about 50 times that for a clearance-fit bolt. Crack initiation was predicted to occur on the transverse axis at a distance of about one radius from the hole.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 8 2010-01-01 2010-01-01 false Powers. 915.28 Section 915.28 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE AVOCADOS GROWN IN SOUTH FLORIDA Order...
Code of Federal Regulations, 2013 CFR
2013-01-01
... 7 Agriculture 8 2013-01-01 2013-01-01 false Powers. 925.28 Section 925.28 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE GRAPES GROWN IN A DESIGNATED AREA OF...
Code of Federal Regulations, 2011 CFR
2011-01-01
... 7 Agriculture 8 2011-01-01 2011-01-01 false Powers. 925.28 Section 925.28 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE GRAPES GROWN IN A DESIGNATED AREA OF...
Code of Federal Regulations, 2014 CFR
2014-01-01
... 7 Agriculture 8 2014-01-01 2014-01-01 false Powers. 925.28 Section 925.28 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE GRAPES GROWN IN A DESIGNATED AREA OF...
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 8 2010-01-01 2010-01-01 false Powers. 925.28 Section 925.28 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE GRAPES GROWN IN A DESIGNATED AREA OF...
Code of Federal Regulations, 2012 CFR
2012-01-01
... 7 Agriculture 8 2012-01-01 2012-01-01 false Powers. 925.28 Section 925.28 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE GRAPES GROWN IN A DESIGNATED AREA OF...
Code of Federal Regulations, 2014 CFR
2014-01-01
... 7 Agriculture 8 2014-01-01 2014-01-01 false Powers. 989.35 Section 989.35 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE RAISINS PRODUCED FROM GRAPES GROWN IN...
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 8 2010-01-01 2010-01-01 false Powers. 966.34 Section 966.34 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Order Regulating...
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 8 2010-01-01 2010-01-01 false Powers. 983.44 Section 983.44 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE PISTACHIOS GROWN IN CALIFORNIA, ARIZONA, AND...
Code of Federal Regulations, 2013 CFR
2013-01-01
... 7 Agriculture 8 2013-01-01 2013-01-01 false Powers. 929.30 Section 929.30 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE CRANBERRIES GROWN IN STATES OF MASSACHUSETTS...
Code of Federal Regulations, 2011 CFR
2011-01-01
... 7 Agriculture 8 2011-01-01 2011-01-01 false Powers. 929.30 Section 929.30 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE CRANBERRIES GROWN IN STATES OF MASSACHUSETTS...
Code of Federal Regulations, 2012 CFR
2012-01-01
... 7 Agriculture 8 2012-01-01 2012-01-01 false Powers. 929.30 Section 929.30 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE CRANBERRIES GROWN IN STATES OF MASSACHUSETTS...
Code of Federal Regulations, 2014 CFR
2014-01-01
... 7 Agriculture 8 2014-01-01 2014-01-01 false Powers. 929.30 Section 929.30 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE CRANBERRIES GROWN IN STATES OF MASSACHUSETTS...
Code of Federal Regulations, 2014 CFR
2014-01-01
... 7 Agriculture 8 2014-01-01 2014-01-01 false Powers. 955.30 Section 955.30 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE VIDALIA ONIONS GROWN IN GEORGIA Committee...
Code of Federal Regulations, 2011 CFR
2011-01-01
... 7 Agriculture 8 2011-01-01 2011-01-01 false Powers. 955.30 Section 955.30 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE VIDALIA ONIONS GROWN IN GEORGIA Committee...
Code of Federal Regulations, 2012 CFR
2012-01-01
... 7 Agriculture 8 2012-01-01 2012-01-01 false Powers. 955.30 Section 955.30 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE VIDALIA ONIONS GROWN IN GEORGIA Committee...
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 8 2010-01-01 2010-01-01 false Powers. 955.30 Section 955.30 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE VIDALIA ONIONS GROWN IN GEORGIA Committee...
Code of Federal Regulations, 2013 CFR
2013-01-01
... 7 Agriculture 8 2013-01-01 2013-01-01 false Powers. 955.30 Section 955.30 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE VIDALIA ONIONS GROWN IN GEORGIA Committee...
Code of Federal Regulations, 2013 CFR
2013-01-01
... 7 Agriculture 8 2013-01-01 2013-01-01 false Powers. 993.35 Section 993.35 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE DRIED PRUNES PRODUCED IN CALIFORNIA Order...
Code of Federal Regulations, 2012 CFR
2012-01-01
... 7 Agriculture 8 2012-01-01 2012-01-01 false Powers. 993.35 Section 993.35 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE DRIED PRUNES PRODUCED IN CALIFORNIA Order...
Code of Federal Regulations, 2011 CFR
2011-01-01
... 7 Agriculture 8 2011-01-01 2011-01-01 false Powers. 993.35 Section 993.35 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE DRIED PRUNES PRODUCED IN CALIFORNIA Order...
Code of Federal Regulations, 2014 CFR
2014-01-01
... 7 Agriculture 8 2014-01-01 2014-01-01 false Powers. 993.35 Section 993.35 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE DRIED PRUNES PRODUCED IN CALIFORNIA Order...
Code of Federal Regulations, 2012 CFR
2012-01-01
... 7 Agriculture 8 2012-01-01 2012-01-01 false Powers. 915.28 Section 915.28 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE AVOCADOS GROWN IN SOUTH FLORIDA Order...
Code of Federal Regulations, 2013 CFR
2013-01-01
... 7 Agriculture 8 2013-01-01 2013-01-01 false Powers. 915.28 Section 915.28 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE AVOCADOS GROWN IN SOUTH FLORIDA Order...
High specific power, direct methanol fuel cell stack
Ramsey, John C [Los Alamos, NM; Wilson, Mahlon S [Los Alamos, NM
2007-05-08
The present invention is a fuel cell stack including at least one direct methanol fuel cell. A cathode manifold is used to convey ambient air to each fuel cell, and an anode manifold is used to convey liquid methanol fuel to each fuel cell. Tie-bolt penetrations and tie-bolts are spaced evenly around the perimeter to hold the fuel cell stack together. Each fuel cell uses two graphite-based plates. One plate includes a cathode active area that is defined by serpentine channels connecting the inlet manifold with an integral flow restrictor to the outlet manifold. The other plate includes an anode active area defined by serpentine channels connecting the inlet and outlet of the anode manifold. Located between the two plates is the fuel cell active region.
An elastic analysis of stresses in a uniaxially loaded sheet containing an interference-fit bolt
NASA Technical Reports Server (NTRS)
Crews, J. H., Jr.
1972-01-01
The stresses in a sheet with an interference-fit bolt have been calculated for two sheet-bolt interface conditions: a frictionless interface and a fixed (no-slip) interface. The stress distributions were calculated for various combinations of sheet and bolt moduli. The results show that for repeated loading the local stress range is significantly smaller if an interference bolt is used instead of a loosely fitting one. This reduction in local stress range is more pronounced when the ratio of bolt modulus to sheet modulus is large. The analysis also indicates that currently used standard values of interference cause yielding in the sheet.
Analysis on Sealing Reliability of Bolted Joint Ball Head Component of Satellite Propulsion System
NASA Astrophysics Data System (ADS)
Guo, Tao; Fan, Yougao; Gao, Feng; Gu, Shixin; Wang, Wei
2018-01-01
Propulsion system is one of the important subsystems of satellite, and its performance directly affects the service life, attitude control and reliability of the satellite. The Paper analyzes the sealing principle of bolted joint ball head component of satellite propulsion system and discuss from the compatibility of hydrazine anhydrous and bolted joint ball head component, influence of ground environment on the sealing performance of bolted joint ball heads, and material failure caused by environment, showing that the sealing reliability of bolted joint ball head component is good and the influence of above three aspects on sealing of bolted joint ball head component can be ignored.
Monitoring bolt torque levels through signal processing of full-field ultrasonic data
NASA Astrophysics Data System (ADS)
Haynes, Colin; Yeager, Michael; Todd, Michael; Lee, Jung-Ryul
2014-03-01
Using full-field ultrasonic guided wave data can provide a wealth of information on the state of a structure through a detailed characterization of its wave propagation properties. However, the need for appropriate feature selection and quantified metrics for making rigorous assessments of the structural state is in no way lessened by the density of information. In this study, a simple steel bolted connection with two bolts is monitored for bolt loosening. The full-field data were acquired using a scanning-laser-generated ultrasound system with a single surface-mounted sensor. Such laser systems have many advantages that make them attractive for nondestructive evaluation, including their high-speed, high spatial resolution, and the ability to scan large areas of in-service structures. In order to characterize the relationship between bolt torque and the resulting wavefield in this specimen, the bolt torque in each of the bolts is independently varied from fully tightened to fully loosened in several steps. First, qualitative observations about the changes in the wavefield are presented. Next, an approach to quantifying the wave transmission through the bolted joint is discussed. Finally, a method of monitoring the bolt torque using the ultrasonic data is demonstrated.
MADS-Box Genes and Gibberellins Regulate Bolting in Lettuce (Lactuca sativa L.)
Han, Yingyan; Chen, Zijing; Lv, Shanshan; Ning, Kang; Ji, Xueliang; Liu, Xueying; Wang, Qian; Liu, Renyi; Fan, Shuangxi; Zhang, Xiaolan
2016-01-01
Bolting in lettuce is promoted by high temperature and bolting resistance is of great economic importance for lettuce production. But how bolting is regulated at the molecular level remains elusive. Here, a bolting resistant line S24 and a bolting sensitive line S39 were selected for morphological, physiological, transcriptomic and proteomic comparisons. A total of 12204 genes were differentially expressed in S39 vs. S24. Line S39 was featured with larger leaves, higher levels of chlorophyll, soluble sugar, anthocyanin and auxin, consistent with its up-regulation of genes implicated in photosynthesis, oxidation-reduction and auxin actions. Proteomic analysis identified 30 differentially accumulated proteins in lines S39 and S24 upon heat treatment, and 19 out of the 30 genes showed differential expression in the RNA-Seq data. Exogenous gibberellins (GA) treatment promoted bolting in both S39 and S24, while 12 flowering promoting MADS-box genes were specifically induced in line S39, suggesting that although GA regulates bolting in lettuce, it may be the MADS-box genes, not GA, that plays a major role in differing the bolting resistance between these two lettuce lines. PMID:28018414
Alignment Pins for Assembling and Disassembling Structures
NASA Technical Reports Server (NTRS)
Campbell, Oliver C.
2008-01-01
Simple, easy-to-use, highly effective tooling has been devised for maintaining alignment of bolt holes in mating structures during assembly and disassembly of the structures. The tooling was originally used during removal of a body flap from the space shuttle Atlantis, in which misalignments during removal of the last few bolts could cause the bolts to bind in their holes. By suitably modifying the dimensions of the tooling components, the basic design of the tooling can readily be adapted to other structures that must be maintained in alignment. The tooling includes tapered, internally threaded alignment pins designed to fit in the bolt holes in one of the mating structures, plus a draw bolt and a cup that are used to install or remove each alignment pin. In preparation for disassembly of two mating structures, external supports are provided to prevent unintended movement of the structures. During disassembly of the structures, as each bolt that joins the structures is removed, an alignment pin is installed in its place. Once all the bolts have been removed and replaced with pins, the pins maintain alignment as the structures are gently pushed or pulled apart on the supports. In assembling the two structures, one reverses the procedure described above: pins are installed in the bolt holes, the structures are pulled or pushed together on the supports, then the pins are removed and replaced with bolts. The figure depicts the tooling and its use. To install an alignment pin in a bolt hole in a structural panel, the tapered end of the pin is inserted from one side of the panel, the cup is placed over the pin on the opposite side of the panel, the draw bolt is inserted through the cup and threaded into the pin, the draw bolt is tightened to pull the pin until the pin is seated firmly in the hole, then the draw bolt and cup are removed, leaving the pin in place. To remove an alignment pin, the cup is placed over the pin on the first-mentioned side of the panel, the draw bolt is inserted through the cup and threaded into the pin, then the draw bolt is tightened to pull the pin out of the hole.
Sleeve expansion of bolt holes in railroad rail. volume III - field experiment results
DOT National Transportation Integrated Search
1998-02-01
The bolt-hole cold-expansion process has been demonstrated by laboratory tests to significantly affect the initiation and propagation of fatigue cracks from rail bolt holes such that a reduction of the incidence of rail-bolt-holde failure in cold-exp...
A Novel RFID-Based Sensing Method for Low-Cost Bolt Loosening Monitoring
Wu, Jian; Cui, Xingmei; Xu, Yunpeng
2016-01-01
In coal mines, bolt loosening in the cage guide is affected by the harsh environmental factors and cage hoist vibration, leading to significant threats to work safety. It is crucial, to this effect, to successfully detect the status of multipoint bolts of guide structures. This paper proposes a system to monitor bolt status in harsh environments established based on the RFID technique. A proof-of-concept model was demonstrated consisting of a bolt gearing system, passive UHF RFID tags, a reader, and monitoring software. A tinfoil metal film is fixed on the retaining plate and an RFID tag bonded to a large gear, with the bolt to be detected fixed in the center of a smaller gear. The radio-frequency signal cannot be received by the reader if the tag is completely obscured by the tinfoil, and if the bolt is loose, the tag’s antenna is exposed when the gear revolves. A radio-frequency signal that carries corresponding bolt’s information is transmitted by the RFID tag to the RFID reader due to coil coupling, identifying loose bolt location and reporting them in the software. Confirmatory test results revealed that the system indeed successfully detects bolt loosening and comparative test results (based on a reed switch multipoint bolt loosening monitor system) provided valuable information regarding the strengths and weaknesses of the proposed system. PMID:26828498
Laboratory testing of a long expansion rock bolt support for energy-absorbing applications
NASA Astrophysics Data System (ADS)
Skrzypkowski, Krzysztof
2018-01-01
The main purpose of rock support and reinforcement in underground mining is to maintain excavations safe and open for their intended lifespan. The basic type of rock mass reinforcement method both in ore and hard coal mining is rock bolt support. Very often, existing bolt support systems are not always capable of providing a reliable controlled performance. Therefore, in recent years energy-absorbing bolts which are exposed to dynamic loading, for example from rock burst caused by high rock stresses, earthquakes, or blasting have appeared. In this article particular attention was paid to short and long expansion bolts. Quasi-static tests of expansion bolts were carried out at the laboratory test facility in simulated mining conditions, especially for the KGHM Polska Miedź S.A. mines. In the underground mines of the Legnica-Głogów Copper District (LGOM) the main way to protect the room excavation is rock bolt support with a length from 1.2 m to 2.6 m. Rock bolt support longer than 2.6 m is considered as additional support of excavations and is increasingly being used to reinforce the roofs. The comparisons of energy-absorbing short and long expansion bolts with a length of 1.8m, 3.6m and 5.2m were presented. In addition, for elastic and plastic range of each bolts were determined.
Shear joint capability versus bolt clearance
NASA Technical Reports Server (NTRS)
Lee, H. M.
1992-01-01
The results of a conservative analysis approach into the determination of shear joint strength capability for typical space-flight hardware as a function of the bolt-hole clearance specified in the design are presented. These joints are comprised of high-strength steel fasteners and abutments constructed of aluminum alloys familiar to the aerospace industry. A general analytical expression was first arrived at which relates bolt-hole clearance to the bolt shear load required to place all joint fasteners into a shear transferring position. Extension of this work allowed the analytical development of joint load capability as a function of the number of fasteners, shear strength of the bolt, bolt-hole clearance, and the desired factor of safety. Analysis results clearly indicate that a typical space-flight hardware joint can withstand significant loading when less than ideal bolt hole clearances are used in the design.
NASA Astrophysics Data System (ADS)
Huong, Khang T.; Nguyen, Cung H.
2018-04-01
Nowadays, steel structure industry in Vietnam is in strong development. The construction of steel structure becomes larger span and heavier load. The issue spawned a number of issues arise from optimizing connections. Typical of steel connections in prefabricated steel structure that is an end plate (face plate) bolted connection. When the connection carried a heavy load, then the number of bolts is required much more. Increasing the number of rows bolts will less effective because can still not enough strength requirements, the bolts in row near rotational center will level arm reduction, then it cannot carry heavy loads. The current solution is doing multiple bolts in a row. Current standards such as EN [1], AISC [2] are no specific guidelines for calculating the connection four bolts in a row that primarily assumes the way works like a T-stub of the two bolts a row. Some articles studied T-stub four bolts in a row [3], [4], [5], [6] by component method but it has some components which weren’t considered. In this paper, in order to provide a contribution to improve the T-stub four bolts in a row, the stiffener component in T-stub will be added and compared with T-stub without stiffener by the finite element model to demonstrate effectiveness in reducing stress and displacement of T-stub. It gives ideas for the economic design of four bolts in a row end plate connection in Vietnam for future.
NASA Astrophysics Data System (ADS)
Adachi, Kazunari; Suzuki, Kohei; Shibamata, Yuki
2018-06-01
We previously developed a 100 W piezoelectric transformer comprising two identical bolt-clamped Langevin-type transducers (BLTs) and a stepped horn whose cross-sectional area ratio determines the specified step-up voltage transformation ratio. Unlike conventional piezoelectric transformers, this transformer is driven at a frequency quite near its mechanical resonance, and thus can be mechanically held firmly at its clearly identified vibratory node without mechanical energy loss. However, it has been revealed that the high-power operation of the transformer often becomes very unstable owing to the “jumping and dropping” phenomena first found by Takahashi and Hirose [Jpn. J. Appl. Phys. 31, 3055 (1992)]. To avoid this instability, we have investigated the peculiar phenomena, and found that they can be attributed to a heavily distorted electric field inside the piezoelectric ceramic disks of the BLT on the primary side of the transformer being driven by a low-impedance voltage source near the mechanical resonance. The resultant concentration of the electric field leads to the local reversal of piezoelectric polarization in every half period of the vibration, viz., the instability. Consequently, we have developed a scheme for the steady high-power operation of this type of piezoelectric transformer and examined its validity experimentally. The method has eventually improved the linearity and power transfer efficiency of the transformer significantly.
Thermal Interface Comparisons Under Flight Like Conditions
NASA Technical Reports Server (NTRS)
Rodriquez-Ruiz, Juan
2008-01-01
Thermal interface materials are used in bolted interfaces to promote good thermal conduction between the two. The mounting surface can include panels, heat pipes, electronics boxes, etc.. . On Lunar Reconnaissance Orbiter (LRO) project the results are directly applicable: a) Several high power avionics boxes b) Several interfaces from RWA to radiator through heat pipe network
17. Detail view of ceiling and beams on third floor ...
17. Detail view of ceiling and beams on third floor of south section of mill. Note the broom attached to the ceiling, which was used to sweep the leather belts used for power transmission, and the bearing pads bolted to the ceiling as well. - Lowe Mill, Eighth Avenue, Southwest, Huntsville, Madison County, AL
View of the STS-88 crew at work in the FGB/Zarya module
1998-12-11
STS088-357-011 (4-15 Dec. 1998) --- Astronaut Nancy J. Currie, mission specialist, and cosmonaut Sergei K. Krikalev, mission specialist representing the Russian Space Agency (RSA), work in the FGB or Zarya Module of the International Space Station (ISS). The two are using battery powered tools to extract bolts.
77 FR 63268 - Airworthiness Directives; Airbus Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2012-10-16
... link bolts, center sway link bolts, and thrust link bolts on the forward engine mounts. This proposed... forward engine mounts. This condition, if left uncorrected, could result in a deterioration of the structural integrity of the front engine mount bolts [and possible damage to an engine or wing]. For the...
Sleeve Expansion of Bolt Holes in Railroad Rail : Volume I, Description and Planning
DOT National Transportation Integrated Search
1980-02-01
The most predominant failure mode of rails with bolt joints is a web crack initiating at the rail bolt hole. This failure mode is of a classical fatigue nature induced by web stress concentration around the bolt hole. This program was conducted to ap...
Code of Federal Regulations, 2014 CFR
2014-07-01
... would not anchor in competent strata, corrective action shall be taken. (3) The installed torque or.... (4) In each roof bolting cycle, the actual torque or tension of the first tensioned roof bolt... drill head used, at least one roof bolt out of every four installed shall be measured for actual torque...
Code of Federal Regulations, 2011 CFR
2011-01-01
... 7 Agriculture 8 2011-01-01 2011-01-01 false Powers. 956.30 Section 956.30 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE SWEET ONIONS GROWN IN THE WALLA WALLA VALLEY...
Code of Federal Regulations, 2012 CFR
2012-01-01
... 7 Agriculture 8 2012-01-01 2012-01-01 false Powers. 956.30 Section 956.30 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE SWEET ONIONS GROWN IN THE WALLA WALLA VALLEY...
Code of Federal Regulations, 2014 CFR
2014-01-01
... 7 Agriculture 8 2014-01-01 2014-01-01 false Powers. 956.30 Section 956.30 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE SWEET ONIONS GROWN IN THE WALLA WALLA VALLEY...
Code of Federal Regulations, 2013 CFR
2013-01-01
... 7 Agriculture 8 2013-01-01 2013-01-01 false Powers. 956.30 Section 956.30 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE SWEET ONIONS GROWN IN THE WALLA WALLA VALLEY...
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 8 2010-01-01 2010-01-01 false Powers. 956.30 Section 956.30 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE SWEET ONIONS GROWN IN THE WALLA WALLA VALLEY...
7 CFR 905.30 - Powers of the committee.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 8 2010-01-01 2010-01-01 false Powers of the committee. 905.30 Section 905.30 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE ORANGES, GRAPEFRUIT, TANGERINES...
NASA Technical Reports Server (NTRS)
Onstott, Joseph W.; Gilster, Mark; Rodriguez, Sergio; Larson, John E.; Wickham, Mark D.; Schoonover, Kevin E.
1995-01-01
Bolts that arrest (or, more precisely, retard) onset of fatigue cracking caused by inelastic strains developed. Specifically developed to be installed in flange holes of unrestrained rocket engine nozzle. Fanges sometimes used to bolt nozzle to test stand; however, when rocket engine operated without this restraint, region around bolt holes experience severe inelastic strains causing fatigue cracking. Interference fits introduce compressive preloads that retard fatigue by reducing ranges of strains. Principle of these fatigue-arrestor bolts also applicable to holes in plates made of other materials and/or used for different purposes.
33. Three bolts on railing outside control house on north ...
33. Three bolts on railing outside control house on north tower, one bolt on first handrail post of the north span (bridge is in the open position). As the bridge opens or closes the single bolt on the handrail post moves past the three stationary bolts. This system is used by the bridge operator to judge speed and position of the north span as it opens or closes. Based on these bolts movement of the north span is speeded up or slowed down and the brakes applied during the opening and closing process. View facing east. - Henry Ford Bridge, Spanning Cerritos Channel, Los Angeles-Long Beach Harbor, Los Angeles, Los Angeles County, CA
Conceptual Design Study on Bolts for Self-Loosing Preventable Threaded Fasteners
NASA Astrophysics Data System (ADS)
Noma, Atsushi; He, Jianmei
2017-11-01
Threaded fasteners using bolts is widely applied in industrial field as well as various fields. However, threaded fasteners using bolts have loosing problems and cause many accidents. In this study, the purpose is to obtain self-loosing preventable threaded fasteners by applying spring characteristic effects on bolt structures. Helical-cutting applied bolt structures is introduced through three dimensional (3D) CAD modeling tools. Analytical approaches for evaluations on the spring characteristic effects helical-cutting applied bolt structures and self-loosing preventable performance of threaded fasteners were performed using finite element method and results are reported. Comparing slackness test results with analytical results and more details on evaluating mechanical properties will be executed in future study.
NASA Technical Reports Server (NTRS)
2002-01-01
Developed in response to a NASA requirement to remotely measure tension in critical bolts on the International Space Station, the SureBolt(TM) Correlation Bolt Gage is the first ultrasonic system to capture an entire "echo" pulse for determining the change in time of flight of an ultrasonic signal traversing a fastener for tension measurement. The standard SureBolt system hardware has the capability of recording over 1 million bolt tension readings-with their complete waveforms-in Microsoft Excel-compatible format. The user- friendly Tension-Not-Torque(Copyright) software interface offers tension change graphing in real time, and a place to store field notes, special parameters, tension calibration constants, and temperature changes for each measurement. The technology has been used on fasteners as small as fine-threaded, 1-inch bolts, and as large as 18-inch-diameter by 30-foot-long tie rods. SureBolt is finding increased application within NASA and the aerospace industry, as well as in the automotive and nuclear industries.
Removable Type Expansion Bolt Innovative Design
NASA Astrophysics Data System (ADS)
Wang, Feng-Lan; Zhang, Bo; Gao, Bo; Liu, Yan-Xin; Gao, Bo
2016-05-01
Expansion bolt is a kind of the most common things in our daily life. Currently, there are many kinds of expansion bolts in the market. However, they have some shortcomings that mainly contain underuse and unremovement but our innovation of design makes up for these shortcomings very well. Principle of working follows this: expansion tube is fixed outside of bolt, steel balls and expansion covers are fixed inside. Meanwhile, the steel balls have 120° with each other. When using it ,expansion cover is moved in the direction of its internal part. So the front part of expansion bolt cover is increasingly becoming big and steel halls is moved outside. Only in this way can it be fixed that steel balls make expansion tube expand. When removing them, expansion bolt is moved outside. So the front part of expansion bolt cover is gradually becoming small and steel balls moves inside, after expansion tube shrinks, we can detach them.
Bolted joints in graphite-epoxy composites
NASA Technical Reports Server (NTRS)
Hart-Smith, L. J.
1976-01-01
All-graphite/epoxy laminates and hybrid graphite-glass/epoxy laminates were tested. The tests encompassed a range of geometries for each laminate pattern to cover the three basic failure modes - net section tension failure through the bolt hole, bearing and shearout. Static tensile and compressive loads were applied. A constant bolt diameter of 6.35 mm (0.25 in.) was used in the tests. The interaction of stress concentrations associated with multi-row bolted joints was investigated by testing single- and double-row bolted joints and open-hole specimens in tension. For tension loading, linear interaction was found to exist between the bearing stress reacted at a given bolt hole and the remaining tension stress running by that hole to be reacted elsewhere. The interaction under compressive loading was found to be non-linear. Comparative tests were run using single-lap bolted joints and double-lap joints with pin connection. Both of these joint types exhibited lower strengths than were demonstrated by the corresponding double-lap joints. The analysis methods developed here for single bolt joints are shown to be capable of predicting the behavior of multi-row joints.
Relationship between locking-bolt torque and load pre-tension in the Ilizarov frame.
Osei, N A; Bradley, B M; Culpan, P; Mitchell, J B; Barry, M; Tanner, K E
2006-10-01
The wire-bolt interface in an Ilizarov frame has been mechanically tested. The optimal torque to be applied to the frame locking-bolts during physiological loading has been defined. The set-up configuration was as is used clinically except a copper tube was used to simulate bone. The force-displacement curves of the Ilizarov wires are not altered by locking-bolt torque. The force in the bone model at which pre-tension is lost increases as the locking-bolts are tightened to 14 Nm torque, but decreases if torque exceeds 14 Nm. Thus, 14 Nm is the optimal locking-bolt torque in frame. The relationship between pre-tension versus load for different locking-bolt torques arises because at low and high clamping torques poor wire holding and plastic deformation respectively occur. Wire damage was seen under light and electron microscopy. Clinically, over or under-tightening locking-bolts will cause loss of pre-tension, reduction in frame stiffness and excessive movement at the fracture site, which may be associated with delayed union.
Causes of Failure of High-Tensile Stud Bolts Used for Joining Metal Parts of Tower Crane
NASA Astrophysics Data System (ADS)
Tingaev, A. K.; Gubaydulin, R. G.; Shaburova, N. A.
2017-11-01
The causes of the failure of a high-tensile stud 2M48-6gx500 10.9 made from steel grade 30HGSA which led to a temporary inoperability of a tower crane were investigated. The bolts were used to assemble the tower sections and collapsed after 45 days from the moment the crane was commissioned. The cracks in the fracture are identified as fatigue with the characteristic sites of nucleation, sustainable development and static dolomite. To determine the possible causes of stud bolts destruction, metallographic, durometric and mechanical tests were carried out from which it follows that the stud bolt material in its original state corresponded to the delivery conditions. The destruction of the stud bolt appears to have resulted from a combination of several unfavorable factors: uncertainty about the actual tension of the stud bolt due to the lack of information about the magnitude of the twist factor; partial displacement of the centers of the brackets holes and rotation of the stud bolt axis during the sections’ assembly; no tight contact on the support surfaces of the section brackets. All this led to a discrepancy between the actual design of the stud bolt, the appearance of additional forces and the destruction of the stud bolt.
NASA Technical Reports Server (NTRS)
Kradinov, V.; Madenci, E.; Ambur, D. R.
2004-01-01
Although two-dimensional methods provide accurate predictions of contact stresses and bolt load distribution in bolted composite joints with multiple bolts, they fail to capture the effect of thickness on the strength prediction. Typically, the plies close to the interface of laminates are expected to be the most highly loaded, due to bolt deformation, and they are usually the first to fail. This study presents an analysis method to account for the variation of stresses in the thickness direction by augmenting a two-dimensional analysis with a one-dimensional through the thickness analysis. The two-dimensional in-plane solution method based on the combined complex potential and variational formulation satisfies the equilibrium equations exactly, and satisfies the boundary conditions and constraints by minimizing the total potential. Under general loading conditions, this method addresses multiple bolt configurations without requiring symmetry conditions while accounting for the contact phenomenon and the interaction among the bolts explicitly. The through-the-thickness analysis is based on the model utilizing a beam on an elastic foundation. The bolt, represented as a short beam while accounting for bending and shear deformations, rests on springs, where the spring coefficients represent the resistance of the composite laminate to bolt deformation. The combined in-plane and through-the-thickness analysis produces the bolt/hole displacement in the thickness direction, as well as the stress state in each ply. The initial ply failure predicted by applying the average stress criterion is followed by a simple progressive failure. Application of the model is demonstrated by considering single- and double-lap joints of metal plates bolted to composite laminates.
Amin, Muhammad Nasir; Zaheer, Salman; Alazba, Abdulrahman Ali; Saleem, Muhammad Umair; Niazi, Muhammad Umar Khan; Khurram, Nauman; Amin, Muhammad Tahir
2016-01-01
Structural hollow sections are gaining worldwide importance due to their structural and architectural advantages over open steel sections. The only obstacle to their use is their connection with other structural members. To overcome the obstacle of tightening the bolt from one side has given birth to the concept of blind bolts. Blind bolts, being the practical solution to the connection hindrance for the use of hollow and concrete filled hollow sections play a vital role. Flowdrill, the Huck High Strength Blind Bolt and the Lindapter Hollobolt are the well-known commercially available blind bolts. Although the development of blind bolts has largely resolved this issue, the use of structural hollow sections remains limited to shear resistance. Therefore, a new modified version of the blind bolt, known as the “Extended Hollo-Bolt” (EHB) due to its enhanced capacity for bonding with concrete, can overcome the issue of low moment resistance capacity associated with blind-bolted connections. The load transfer mechanism of this recently developed blind bolt remains unclear, however. This study uses a parametric approach to characterising the EHB, using diameter as the variable parameter. Stiffness and load-carrying capacity were evaluated at two different bolt sizes. To investigate the load transfer mechanism, a component-based study of the bond and anchorage characteristics was performed by breaking down the EHB into its components. The results of the study provide insight into the load transfer mechanism of the blind bolt in question. The proposed component-based model was validated by a spring model, through which the stiffness of the EHB was compared to that of its components combined. The combined stiffness of the components was found to be roughly equivalent to that of the EHB as a whole, validating the use of this component-based approach. PMID:26901866
Evaluation of bolted connections in wood-plastic composites
NASA Astrophysics Data System (ADS)
Arnandha, Yudhi; Satyarno, Iman; Awaludin, Ali; Irawati, Inggar Septia; Ihsan, Muhamad; Wijanarko, Felyx Biondy; William, Mahdinur, Fardhani, Arfiati
2017-03-01
Wood-plastic composite (WPC) is a relatively new material that consists of sawdust and plastic polymer using the extrusion process. Due to its attributes such as low water content, low maintenance, UV durability and being fungi and termite resistant. Nowadays, WPC has already been produced in Indonesia using sawdust from local wood such as Albizia (Paraserianthes falcataria) and Teak (Tectona grandis). Moreover preliminary studies about the physical and mechanical WPC board from Albizia sawdust and HDPE plastic have been carried out. Based on these studies, WPC has a high shear strength around 25-30 MPa higher than its original wood shear strength. This paper was a part of the research in evaluating WPC as potential sheathing in a shear wall system. Since still little is known about connection behavior in WPC using Indonesian local wood, this study evaluated the connection for both of these two types of wood-plastic composite. WPC board from Albizia sawdust will be projected as shear wall sheathing and WPC stud from Teak sawdust projected to be shear wall frame. For this study, the embedding strength for both WPC was determined according to ASTM D 5764 standard, using two types of bolts (stainless bolt and standard bolt) with several diameters as variation (6 mm, 8 mm, 10 and 12 mm). Hence, dowel-bearing test under fastened condition conducted accordance to ASTM D5652, hereby the yield strength then compared with the prediction yield strength from European Yield Model (EYM). According to both single and double shear connection, it can be concluded that yield strength from the EYM method tended to under-predict the 5% diameter offset yield than the actual yield strength from the test. The yield strength itself increase with the increase of bolt diameter. For single shear connection, the highest yield strength was 12 mm standard bolt around 9732 N, slightly higher than stainless bolt around 9393 N. Whereby for double shear connection, the highest yield strength was 12 mm standard bolt around 12009 N, slightly higher than stainless bolt around 12009 N. Using statistical approach ANOVA, the different type of bolt between stainless bolt and standard bolt gave an insignificant result. Both type of bolt can be used as structural connection, moreover it was recommended using a stainless bolt for outdoor purpose to reduce corrosion.
A Generalized Machine Fault Detection Method Using Unified Change Detection
2014-10-02
SOCIETY 2014 11 of the extension shaft. It can be induced by a lack of tightening torque of the end-nut and consequently causes a load...Test Facility (HTTF). The objective of the study was to provide HUMS systems with the capability to detect the loss of tightening torque of the end...from pinion SSA (at Ring-Front sensor & cruise power) change signal with cross-over at 75th shaft order Ten end-nut tightening torques were used in
Code of Federal Regulations, 2012 CFR
2012-07-01
... material in joints and couplings to ensure a leak-free seal; (2) Use a bolt in at least every other hole... chapter; (3) Use a bolt in each hole in each temporary bolted connection that uses a flange other than one that meets ANSI standards; (4) Use a bolt in each hole of each permanently connected flange; (5) Use...
Code of Federal Regulations, 2011 CFR
2011-07-01
... material in joints and couplings to ensure a leak-free seal; (2) Use a bolt in at least every other hole... chapter; (3) Use a bolt in each hole in each temporary bolted connection that uses a flange other than one that meets ANSI standards; (4) Use a bolt in each hole of each permanently connected flange; (5) Use...
Code of Federal Regulations, 2014 CFR
2014-07-01
... material in joints and couplings to ensure a leak-free seal; (2) Use a bolt in at least every other hole... chapter; (3) Use a bolt in each hole in each temporary bolted connection that uses a flange other than one that meets ANSI standards; (4) Use a bolt in each hole of each permanently connected flange; (5) Use...
Code of Federal Regulations, 2013 CFR
2013-07-01
... material in joints and couplings to ensure a leak-free seal; (2) Use a bolt in at least every other hole... chapter; (3) Use a bolt in each hole in each temporary bolted connection that uses a flange other than one that meets ANSI standards; (4) Use a bolt in each hole of each permanently connected flange; (5) Use...
Code of Federal Regulations, 2010 CFR
2010-07-01
... material in joints and couplings to ensure a leak-free seal; (2) Use a bolt in at least every other hole... chapter; (3) Use a bolt in each hole in each temporary bolted connection that uses a flange other than one that meets ANSI standards; (4) Use a bolt in each hole of each permanently connected flange; (5) Use...
NASA Astrophysics Data System (ADS)
Ma, Jiansuo; Wang, Yuanqing; Li, Mingfeng; Bai, Runshan; Ban, Huiyong
2018-03-01
In the process of existing steel structure operation, in order to prevent the bolted joints from being damaged by insufficient carrying capacity, welds can be used for reinforcement. Weld reinforced combined connection with bolts and weld consists with high strength bolts and side fillet weld composition. The parameters and properties of high strength bolts and fillet welds have a direct effect on the connection. Based on the test results, We explore the influence that welding seam reinforcement and the performance of the connection between the number of high strength bolts and specifications changes in this paper. It will provide a theoretical reference for the design of connection nodes of steel structure reinforcement project.
NASA Technical Reports Server (NTRS)
Crews, J. H., Jr.
1975-01-01
A fatigue analysis, based on finite-element calculations and fatigue tests, was conducted for an aluminum-alloy sheet specimen with a steel interference-fit bolt. The stress analysis of the region near the bolt hole showed that the beneficial effect of an interference-fit bolt can be interpreted as the combined result of two effects: (1) load transfer through the bolt and (2) the compressive interference stresses in the sheet. Results of the fatigue tests show that progressively higher interference levels produced longer fatigue lives. The tests also show that a high level of interference prevents fretting at the bolt-sheet interface and that interferences larger than this level produced little additional improvement in fatigue life.
The Nuts and Bolts of Low-level Laser (Light) Therapy
Chung, Hoon; Dai, Tianhong; Sharma, Sulbha K.; Huang, Ying-Ying; Carroll, James D.; Hamblin, Michael R.
2011-01-01
Soon after the discovery of lasers in the 1960s it was realized that laser therapy had the potential to improve wound healing and reduce pain, inflammation and swelling. In recent years the field sometimes known as photobiomodulation has broadened to include light-emitting diodes and other light sources, and the range of wavelengths used now includes many in the red and near infrared. The term “low level laser therapy” or LLLT has become widely recognized and implies the existence of the biphasic dose response or the Arndt-Schulz curve. This review will cover the mechanisms of action of LLLT at a cellular and at a tissular level and will summarize the various light sources and principles of dosimetry that are employed in clinical practice. The range of diseases, injuries, and conditions that can be benefited by LLLT will be summarized with an emphasis on those that have reported randomized controlled clinical trials. Serious life-threatening diseases such as stroke, heart attack, spinal cord injury, and traumatic brain injury may soon be amenable to LLLT therapy. PMID:22045511
Anatomy of the Crowd4Discovery crowdfunding campaign.
Perlstein, Ethan O
2013-01-01
Crowdfunding allows the public to fund creative projects, including curiosity-driven scientific research. Last Fall, I was part of a team that raised $25,460 from an international coalition of "micropatrons" for an open, pharmacological research project called Crowd4Discovery. The goal of Crowd4Discovery is to determine the precise location of amphetamines inside mouse brain cells, and we are sharing the results of this project on the Internet as they trickle in. In this commentary, I will describe the genesis of Crowd4Discovery, our motivations for crowdfunding, an analysis of our fundraising data, and the nuts and bolts of running a crowdfunding campaign. Science crowdfunding is in its infancy but has already been successfully used by an array of scientists in academia and in the private sector as both a supplement and a substitute to grants. With traditional government sources of funding for basic scientific research contracting, an alternative model that couples fundraising and outreach - and in the process encourages more openness and accountability - may be increasingly attractive to researchers seeking to diversify their funding streams.
The Public's Needs (a la Maslow) Drive the Public's Receptivity to Information
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cramer, E.N.
1999-11-14
The communication problem of the nuclear industry is the same as any other nonmonopoly provider of products or services, i.e., to show the public that nuclear electricity is superior even though nuclear electricity itself is indistinguishable from any other electricity. The public wants to know how nuclear compares with other sources of electricity in almost any other way except detailed information on the ''nuts and bolts'' of how electricity is made. They want to learn first, that there is an adequate supply of nuclear fuel and that they will not have to degrade their lifestyle unless they choose to domore » so; second, that they are safe and that meaningful consideration has been given to public safety for nuclear energy generation, including waste disposal; third, that this method is accepted by reputable scientists; fourth, that their use of this method is decreasing world societal problems, causes of war, and causes of pollution; and fifth, that this method increases their ability to accomplish the things that one's potential allows.« less
Improving the machinability of leaded free cutting steel through process optimization
NASA Astrophysics Data System (ADS)
Sathyamurthy, P.; Vetrivelmurugan, R.; Sooryaprakash, J.
2018-02-01
Free cutting steel grades are high sulphur grades which can be classified under two categories as Leaded and Non-Leaded. These grades are used for manufacturing components like Nuts, bolts, studs, hydraulic fittings, brake pistons where higher machining is required to get intricate shape. Machinability of these grades are affected by hard oxide inclusions and highly deformed manganese sulphide inclusions. At JSW, machinability of leaded free cutting steel is improved by various process modifications namely deoxidation through carbon and manganese, Tellurium (Rare earth element) addition and maintaining the oxygen level at 80- 120ppm. Former one avoids the formation of hard SiO2 and Al2O3 compounds, Tellurium addition forms PbTe compound at the tail of MnS inclusions which resists the deformation of MnS inclusions and increased oxygen level favours the formation of less deformable oxy- sulphide inclusions. Above process modifications have resulted in achieving the low silicate content, better aspect ratio of MnS inclusions in the final rolled product. They are assessed by the characteristics of chip formation and surface roughness of machined part.
Modified locking thread form for fastener
NASA Technical Reports Server (NTRS)
Roopnarine, (Inventor); Vranish, John D. (Inventor)
1998-01-01
A threaded fastener has a standard part with a standard thread form characterized by thread walls with a standard included angle, and a modified part complementary to the standard part having a modified thread form characterized by thread walls which are symmetrically inclined with a modified included angle that is different from the standard included angle of the standard part's thread walls, such that the threads of one part make pre-loaded edge contact with the thread walls of the other part. The thread form of the modified part can have an included angle that is greater, less, or compound as compared to the included angle of the standard part. The standard part may be a bolt and the modified part a nut, or vice versa. The modified thread form holds securely even under large vibrational forces, it permits bi-directional use of standard mating threads, is impervious to the build up of tolerances and can be manufactured with a wider range of tolerances without loss of functionality, and distributes loading stresses (per thread) in a manner that decreases the possibility of single thread failure.
Steadman, Patrick E; Crudden, Johanna; Boutis, Kathy
2015-09-01
Prospective research studies often advance clinical practice in the emergency department (ED), but they can be costly and difficult to perform. In this report, we describe the implementation of a volunteer university student research assistant program that provides students exposure to medicine and clinical research while simultaneously increasing the capacity of an ED's research program. This type of program provides 15 hours per day of research assistant coverage for patient screening and enrolment for minimal risk research studies, and screening for higher risk studies. The latter is true without the added burden or costs of co-administering university course credit or pay for service, which are common features of most of these types of programs currently in operation. We have shown that our volunteer-based program is effective for an ED's research success as well as for its student participants. For other EDs interested in adopting similar programs, we provide the details on how to get such a program started and highlight the structure and non-monetary incentives that facilitate a program's ongoing success.
Home retrofitting for energy conservation and solar considerations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1981-10-01
This manual explains both the key concepts behind our need for and our impact on energy usage, as well as a nuts-and-bolts explanation of how to improve the energy efficiency of your home. By reviewing both the concepts and practices of energy conservation, the manual presents a comprehensive picture of how home energy use is effected by the inhabitants and by the structure itself. The manual begins with an explanation of why we are looking at energy, then proceeds to explain how the heat transfer occurs between houses and humans. Next is a chapter on energy audits and how tomore » use them, followed by a comprehensive section on energy conservation actions to do now to reduce energy use. Conservation actions include low cost/no cost measures, schemes to reduce infiltration, how to increase insulation, and what to do with windows and doors, heating and heat distribution systems, and water heaters. Solar energy options are then briefly explained, as well as the all important issues of financing and tax credits. The manual concludes with a bibliography to direct the reader to more sources of information.« less
7. View of turbine pit at an exciter unit showing ...
7. View of turbine pit at an exciter unit showing servo-motor heads (foreground and background at left) with piston rods bolted to the operating ring of the turbine gate (foreground and background at center). View to northeast. - Holter Hydroelectric Facility, Dam & Power House, End of Holter Dam Road, Wolf Creek, Lewis and Clark County, MT
10. VIEW EAST (93 DEGREES) OF RCA COMMUNICATION RECEIVING STATION. ...
10. VIEW EAST (93 DEGREES) OF RCA COMMUNICATION RECEIVING STATION. WOOD FRAMING SUPPORTED STANDOFF INSULATORS AND ANTENNA WIRES COMING FROM THE FIELD INTO THE BUILDING. BOLT ON FOUNDATION POLES SUPPORTED SATELLITE ANTENNAS, METAL CAP AND POSTS AT LEFT PROTECTED CONDUIT SUPPLYING POWER TO SATELLITE ANTENNA MOTORS. - Marconi Radio Sites, Receiving, Point Reyes Station, Marin County, CA
Hildebrand, Richard J.; Wozniak, John J.
2001-01-01
A compressed gas storage cell interconnecting manifold including a thermally activated pressure relief device, a manual safety shut-off valve, and a port for connecting the compressed gas storage cells to a motor vehicle power source and to a refueling adapter. The manifold is mechanically and pneumatically connected to a compressed gas storage cell by a bolt including a gas passage therein.
2010-04-28
34 to 1" drive adapter MHE ============ 15,000 lbs forklift 6,000 lbs. forklift 5,000 pallet truck Two 30,000 lbs. 6’x16’ caster wheeled carts...Suggested modifications to reduce assembly time* ================================================== Use powered torque multipliers to torque bolts
Effects of bolt-hole contact on bearing-bypass damage-onset strength
NASA Technical Reports Server (NTRS)
Crews, John H., Jr.; Naik, Rajiv A.
1991-01-01
A combined experimental and analytical study was conducted to investigate the effects of bolt-hole contact on the bearing bypass strength of a graphite-epoxy laminate. Tests were conducted on specimens consisting of 16-ply quasi-isotropic T300/5208 laminates with a centrally located hole. Bearing loads were applied through a clearance-fit steel bolt. Damage onset strength and damage mode were determined for each test case. A finite element procedure was used to calculate the bolt-hole stresses and bolt contact for each test case. A finite element procedure was used to calculate the bolt-hole stresses and bolt contact for each measured damage-onset strength. For the tension bearing-bypass cases tested, the bolt contact half-angle was approximately 60 degrees at damage onset. For compression, the contact angle was 20 degrees as the bypass load increased. A corresponding decrease in the bearing damage onset strength was attributed to the decrease in contact angle which made the bearing loads more severe. Hole boundary stresses were also computed by superimposing stresses for separate bearing and bypass loading. Stresses at the specimen net section were accurately approximated by the superposition procedure. However, the peak bearing stresses had large errors because the bolt contact angles were not represented correctly. For compression, peak bearing stress errors of nearly 50 percent were calculated.
NASA Technical Reports Server (NTRS)
Goldie, James H.; Bushko, Dariusz A.; Gerver, Michael J.
1995-01-01
In technique for measuring tensile force of bolt, specially fabricated magnetostrictive washer used as force transducer. Compact, portable inductive electronic sensor placed against washer to measure tension force. New system provides accurate, economical, and convenient way to measure bolt tension in field. Measurements on test assembly shows that tension can be measured to accuracy of about plus or minus 1 percent of load capacity of typical bolt.
Thrust bolting: roof bolt support apparatus
Tadolini, Stephen C.; Dolinar, Dennis R.
1992-01-01
A method of installing a tensioned roof bolt in a borehole of a rock formation without the aid of a mechanical anchoring device or threaded tensioning threads by applying thrust to the bolt (19) as the bonding material (7') is curing to compress the strata (3) surrounding the borehole (1), and then relieving the thrust when the bonding material (7') has cured.
Crashworthiness Design of the Shear Bolts for Light Collision Safety Devices
NASA Astrophysics Data System (ADS)
Kim, Jin Sung; Huh, Hoon; Kwon, Tae Soo
This paper introduces the jig set for the crash test and the crash test results of shear bolts which are designed to fail at train crash conditions. The tension and shear bolts are attached to Light Collision Safety Devices(LCSD) as a mechanical fuse when tension and shear bolts reach their failure load designed. The kinetic energy due to the crash is absorbed by the secondary energy absorbing device after LCSD are detached from the main body by the fracture of shear bolts. A single shear bolt was designed to fail at the load of 250 kN. The jig set designed to convert a compressive loading to a shear loading was installed to the high speed crash tester for dynamic shear tests. Two strain gauges were attached at the parallel section of the jig set to measure the load responses acting on the shear bolts. Crash tests were performed with a carrier whose mass was 250 kg and the initial speed of the carrier was 9 m/sec. From the quasi-static and dynamic experiments as well as the numerical analysis, the capacity of the shear bolts were accurately predicted for the crashworthiness design.
NASA Astrophysics Data System (ADS)
Grzejda, R.
2017-12-01
The paper deals with modelling and calculations of asymmetrical multi-bolted joints at the assembly stage. The physical model of the joint is based on a system composed of four subsystems, which are: a couple of joined elements, a contact layer between the elements, and a set of bolts. The contact layer is assumed as the Winkler model, which can be treated as a nonlinear or linear model. In contrast, the set of bolts are modelled using simplified beam models, known as spider bolt models. The theorem according to which nonlinearity of the contact layer has a negligible impact on the final preload of the joint in the case of its sequential tightening has been verified. Results of sample calculations for the selected multi-bolted system, in the form of diagrams of preloads in the bolts as well as normal contact pressure between the joined elements during the assembly process and at its end, are presented.
On-line bolt-loosening detection method of key components of running trains using binocular vision
NASA Astrophysics Data System (ADS)
Xie, Yanxia; Sun, Junhua
2017-11-01
Bolt loosening, as one of hidden faults, affects the running quality of trains and even causes serious safety accidents. However, the developed fault detection approaches based on two-dimensional images cannot detect bolt-loosening due to lack of depth information. Therefore, we propose a novel online bolt-loosening detection method using binocular vision. Firstly, the target detection model based on convolutional neural network (CNN) is used to locate the target regions. And then, stereo matching and three-dimensional reconstruction are performed to detect bolt-loosening faults. The experimental results show that the looseness of multiple bolts can be characterized by the method simultaneously. The measurement repeatability and precision are less than 0.03mm, 0.09mm respectively, and its relative error is controlled within 1.09%.
Simulating the Structural Response of a Preloaded Bolted Joint
NASA Technical Reports Server (NTRS)
Knight, Norman F., Jr.; Phillips, Dawn R.; Raju, Ivatury S.
2008-01-01
The present paper describes the structural analyses performed on a preloaded bolted-joint configuration. The joint modeled was comprised of two L-shaped structures connected together using a single bolt. Each L-shaped structure involved a vertical flat segment (or shell wall) welded to a horizontal segment (or flange). Parametric studies were performed using elasto-plastic, large-deformation nonlinear finite element analyses to determine the influence of several factors on the bolted-joint response. The factors considered included bolt preload, washer-surface-bearing size, edge boundary conditions, joint segment length, and loading history. Joint response is reported in terms of displacements, gap opening, and surface strains. Most of the factors studied were determined to have minimal effect on the bolted-joint response; however, the washer-bearing-surface size affected the response significantly.
Strain measurements in composite bolted-joint specimens
NASA Technical Reports Server (NTRS)
Hyer, M. W.; Lightfoot, M. C.; Perry, J. C.
1979-01-01
Strain data from a series of bolted joint tests is presented. Double lap, double hole, double lap, single hole, and open hole tensile specimens were tested and the strain gage locations, load strain responses, and load axial displacement responses are presented. The open hole specimens were gaged to determine strain concentration factors. The double lap, double hole specimens were gaged to determine the uniformity of the strain in the joint and the amount of load transferred past the first bolt. The measurements indicated roughly half the load passed the first bolt to be reacted by the second bolt.
Pressure Dome for High-Pressure Electrolyzer
NASA Technical Reports Server (NTRS)
Norman, Timothy; Schmitt, Edwin
2012-01-01
A high-strength, low-weight pressure vessel dome was designed specifically to house a high-pressure [2,000 psi (approx. = 13.8 MPa)] electrolyzer. In operation, the dome is filled with an inert gas pressurized to roughly 100 psi (approx. = 690 kPa) above the high, balanced pressure product oxygen and hydrogen gas streams. The inert gas acts to reduce the clamping load on electrolyzer stack tie bolts since the dome pressure acting axially inward helps offset the outward axial forces from the stack gas pressure. Likewise, radial and circumferential stresses on electrolyzer frames are minimized. Because the dome is operated at a higher pressure than the electrolyzer product gas, any external electrolyzer leak prevents oxygen or hydrogen from leaking into the dome. Instead the affected stack gas stream pressure rises detectably, thereby enabling a system shutdown. All electrical and fluid connections to the stack are made inside the pressure dome and require special plumbing and electrical dome interfaces for this to be accomplished. Further benefits of the dome are that it can act as a containment shield in the unlikely event of a catastrophic failure. Studies indicate that, for a given active area (and hence, cell ID), frame outside diameter must become ever larger to support stresses at higher operating pressures. This can lead to a large footprint and increased costs associated with thicker and/or larger diameter end-plates, tie-rods, and the frames themselves. One solution is to employ rings that fit snugly around the frame. This complicates stack assembly and is sometimes difficult to achieve in practice, as its success is strongly dependent on frame and ring tolerances, gas pressure, and operating temperature. A pressure dome permits an otherwise low-pressure stack to operate at higher pressures without growing the electrolyzer hardware. The pressure dome consists of two machined segments. An O-ring is placed in an O-ring groove in the flange of the bottom segment and is trapped by the flange on the top dome segment when these components are bolted together with high-strength bolts. The pressure dome has several unique features. It is made (to ASME Pressure Vessel guidelines) in a high-strength aluminum alloy with the strength of stainless steel and the weight benefits of aluminum. The flange of the upper dome portion contains specially machined flats for mounting the dome, and other flats dedicated to the special feedthroughs for electrical connections. A pressure dome can be increased in length to house larger stacks (more cells) of the same diameter with the simple addition of a cylindrical segment. To aid in dome assembly, two stainless steel rings are employed. One is used beneath the heads of the high-strength bolts in lieu of individual hardened washers, and another is used instead of individual nuts. Like electrolyzers could be operated at low or high pressures simply by operating the electrolyzer outside or inside a pressurized dome.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-11-20
... require recurring visual inspections of the tail rotor (T/R) blade retaining bolts (bolts) for a crack, corrosion, damage, or missing cadmium plating in the central part of the bolt. If a crack is not detected by.... Replacing a cracked or damaged bolt would be required before further flight. This proposed AD is prompted by...
ERIC Educational Resources Information Center
Machiavelli, Nick
1992-01-01
Exploding in anger has its charm, though putting sand in the social oil is not simple. Rudeness, like celebrity deaths, comes in threes: daily, demented, and inspired. Administrators should be forewarned: rudeness is effective only when coming from power. Powerless rude people are called nuts; powerful rude people are deemed eccentric. (MLH)
29 CFR 1926.303 - Abrasive wheels and tools.
Code of Federal Regulations, 2013 CFR
2013-07-01
... and tools. (a) Power. All grinding machines shall be supplied with sufficient power to maintain the spindle speed at safe levels under all conditions of normal operation. (b) Guarding. (1) Grinding machines..., nut, and outer flange may be exposed on machines designed as portable saws. (c) Use of abrasive wheels...
29 CFR 1926.303 - Abrasive wheels and tools.
Code of Federal Regulations, 2014 CFR
2014-07-01
... and tools. (a) Power. All grinding machines shall be supplied with sufficient power to maintain the spindle speed at safe levels under all conditions of normal operation. (b) Guarding. (1) Grinding machines..., nut, and outer flange may be exposed on machines designed as portable saws. (c) Use of abrasive wheels...
29 CFR 1926.303 - Abrasive wheels and tools.
Code of Federal Regulations, 2012 CFR
2012-07-01
... and tools. (a) Power. All grinding machines shall be supplied with sufficient power to maintain the spindle speed at safe levels under all conditions of normal operation. (b) Guarding. (1) Grinding machines..., nut, and outer flange may be exposed on machines designed as portable saws. (c) Use of abrasive wheels...
Epigenomics and bolting tolerance in sugar beet genotypes.
Hébrard, Claire; Peterson, Daniel G; Willems, Glenda; Delaunay, Alain; Jesson, Béline; Lefèbvre, Marc; Barnes, Steve; Maury, Stéphane
2016-01-01
In sugar beet (Beta vulgaris altissima), bolting tolerance is an essential agronomic trait reflecting the bolting response of genotypes after vernalization. Genes involved in induction of sugar beet bolting have now been identified, and evidence suggests that epigenetic factors are involved in their control. Indeed, the time course and amplitude of DNA methylation variations in the shoot apical meristem have been shown to be critical in inducing sugar beet bolting, and a few functional targets of DNA methylation during vernalization have been identified. However, molecular mechanisms controlling bolting tolerance levels among genotypes are still poorly understood. Here, gene expression and DNA methylation profiles were compared in shoot apical meristems of three bolting-resistant and three bolting-sensitive genotypes after vernalization. Using Cot fractionation followed by 454 sequencing of the isolated low-copy DNA, 6231 contigs were obtained that were used along with public sugar beet DNA sequences to design custom Agilent microarrays for expression (56k) and methylation (244k) analyses. A total of 169 differentially expressed genes and 111 differentially methylated regions were identified between resistant and sensitive vernalized genotypes. Fourteen sequences were both differentially expressed and differentially methylated, with a negative correlation between their methylation and expression levels. Genes involved in cold perception, phytohormone signalling, and flowering induction were over-represented and collectively represent an integrative gene network from environmental perception to bolting induction. Altogether, the data suggest that the genotype-dependent control of DNA methylation and expression of an integrative gene network participate in bolting tolerance in sugar beet, opening up perspectives for crop improvement. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.
Study on Fatigue Performance of Composite Bolted Joints with Bolt-Hole Delamination
NASA Astrophysics Data System (ADS)
Liu, M. J.; Yu, S.; Zhao, Q. Y.
2018-03-01
Fatigue performance of composite structure with imperfections is a challenging subject at present. Based on cohesive zone method and multi-continuum theory, delamination evolution response and fatigue life prediction of a 3D composite single-lap joint with a bolt-hole have been investigated through computer codes Abaqus and Fe-safe. Results from the comparison of a perfect composite bolted joint with another defect one indicates that a relatively small delamination damage around the bolt hole brings about significant degradation of local material performance. More notably, fatigue life of stress concentration region of composite bolted joints is highly sensitive to external loads, as an increase of 67% cyclic load amplitude leads to an decrease of 99.5% local fatigue life in this study. However, the numerical strategy for solving composite fatigue problems is meaningful to engineering works.
Luo, Mingzhang; Li, Weijie; Wang, Bo; Fu, Qingqing; Song, Gangbing
2017-02-23
Rock bolts, as a type of reinforcing element, are widely adopted in underground excavations and civil engineering structures. Given the importance of rock bolts, the research outlined in this paper attempts to develop a portable non-destructive evaluation method for assessing the length of installed rock bolts for inspection purposes. Traditionally, piezoelectric elements or hammer impacts were used to perform non-destructive evaluation of rock bolts. However, such methods suffered from many major issues, such as the weak energy generated and the requirement for permanent installation for piezoelectric elements, and the inconsistency of wave generation for hammer impact. In this paper, we proposed a portable device for the non-destructive evaluation of rock bolt conditions based on a giant magnetostrictive (GMS) actuator. The GMS actuator generates enough energy to ensure multiple reflections of the stress waves along the rock bolt and a lead zirconate titantate (PZT) sensor is used to detect the reflected waves. A new integrated procedure that involves correlation analysis, wavelet denoising, and Hilbert transform was proposed to process the multiple reflection signals to determine the length of an installed rock bolt. The experimental results from a lab test and field tests showed that, by analyzing the instant phase of the periodic reflections of the stress wave generated by the GMS transducer, the length of an embedded rock bolt can be accurately determined.
Luo, Mingzhang; Li, Weijie; Wang, Bo; Fu, Qingqing; Song, Gangbing
2017-01-01
Rock bolts, as a type of reinforcing element, are widely adopted in underground excavations and civil engineering structures. Given the importance of rock bolts, the research outlined in this paper attempts to develop a portable non-destructive evaluation method for assessing the length of installed rock bolts for inspection purposes. Traditionally, piezoelectric elements or hammer impacts were used to perform non-destructive evaluation of rock bolts. However, such methods suffered from many major issues, such as the weak energy generated and the requirement for permanent installation for piezoelectric elements, and the inconsistency of wave generation for hammer impact. In this paper, we proposed a portable device for the non-destructive evaluation of rock bolt conditions based on a giant magnetostrictive (GMS) actuator. The GMS actuator generates enough energy to ensure multiple reflections of the stress waves along the rock bolt and a lead zirconate titantate (PZT) sensor is used to detect the reflected waves. A new integrated procedure that involves correlation analysis, wavelet denoising, and Hilbert transform was proposed to process the multiple reflection signals to determine the length of an installed rock bolt. The experimental results from a lab test and field tests showed that, by analyzing the instant phase of the periodic reflections of the stress wave generated by the GMS transducer, the length of an embedded rock bolt can be accurately determined. PMID:28241503
Yield of pallet cants and lumber from hardwood poletimber thinnings
E. Paul Craft; David M. Emanuel
1981-01-01
Woods-run bolts in 4- and 6-foot length from poletimber stand thininings were classified into five quality classes, and the absolute sweep was measured for each bolt. Cants 4 by 4 and 4 by 6 inches were sawn from these bolts. The cants were classified by an interim classification system for the production of pallet parts. In contrast to straight bolts, sweep from 0.6...
A microprocessor based portable bolt tension monitor
NASA Technical Reports Server (NTRS)
Perey, D. F.
1991-01-01
A bolt tension monitor (BTM) which uses ultrasonics and a pulsed phase locked loop circuit to measure load-induced acoustic phase shifts which are independent of friction is described. The BTM makes it possible to measure the load in a bolt that was tightened at some time in the past. This capability to recertify a load after-the-fact will help to insure the integrity of a bolted joint.
System 6: making frame-quality blanks from white oak thinnings
Hugh W. Reynolds; Philip A. Araman
1983-01-01
Low-grade white oak timber removed during a timber stand improvement cut on the Jefferson National Forest in Virginia was made into sawlogs, poles, 6-foot bolts, 4-foot bolts, pulpwood, and firewood. The 6-foot bolts were sawed to two cants per bolt; cants were resawed to 4/4 System 6 boards; boards were dried to 6 percent moisture content and made into frame blanks...
Ding, Xu; Wu, Xinjun; Wang, Yugang
2014-03-01
A method is proposed to measure the stress on a tightened bolt using an electromagnetic acoustic transducer (EMAT). A shear wave is generated by the EMAT, and a longitudinal wave is obtained from the reflection of the shear wave due to the mode conversion. The ray paths of the longitudinal and the shear wave are analyzed, and the relationship between the bolt axial stress and the ratio of time of flight between two mode waves is then formulated. Based on the above outcomes, an EMAT is developed to measure the bolt axial stress without loosening the bolt, which is required in the conventional EMAT test method. The experimental results from the measurement of the bolt tension show that the shear and the mode-converted longitudinal waves can be received successfully, and the ratio of the times of flight of the shear and the mode-converted longitudinal waves is linearly proportional to the bolt axial tension. The non-contact characteristic of EMAT eliminates the effect of the couplant and also makes the measurement more convenient than the measurement performed using the piezoelectric transducer. This method provides a promising way to measure the stress on tightened bolts. Copyright © 2013 Elsevier B.V. All rights reserved.
NASA Technical Reports Server (NTRS)
Gleman, Stuart M. (Inventor); Rowe, Geoffrey K. (Inventor)
1999-01-01
An ultrasonic bolt gage is described which uses a crosscorrelation algorithm to determine a tension applied to a fastener, such as a bolt. The cross-correlation analysis is preferably performed using a processor operating on a series of captured ultrasonic echo waveforms. The ultrasonic bolt gage is further described as using the captured ultrasonic echo waveforms to perform additional modes of analysis, such as feature recognition. Multiple tension data outputs, therefore, can be obtained from a single data acquisition for increased measurement reliability. In addition, one embodiment of the gage has been described as multi-channel, having a multiplexer for performing a tension analysis on one of a plurality of bolts.
Evaluation of mounting bolt loads for Space Shuttle Get Away Special (GAS) adapter beam
NASA Technical Reports Server (NTRS)
Talapatra, D. C.
1983-01-01
During the prototype vibration tests of the GAS adapter beam, significant impacting of the beam at its support points was observed. The cause of the impacting was traced to gaps under the mounting bolt heads. Because of the nonlinear nature of the response, it was difficult to evaluate the effects which Shuttle launch dynamics might have on the mounting bolt loads. A series of tests were conducted on an electrodynamic exciter in which the transient acceleration time histories, which had been measured during the Space Transportation System-1 (STS-1; Space Shuttle mission 1) launch, were simulated. The actual flight data had to be filtered and compensated so that it could be reproduced on the shaker without exceeding displacement and velocity limitations. Mounting bolt loads were measured directly by strain gages applied to the bolts. Various gap thicknesses and bolt torques were investigated. Although increased gap thickness resulted in greater accelerations due to impacting, the bolt loads were not significantly affected. This is attributed to the fact that impacting excited mostly higher frequency modes which do not have significant modal mass.
Nuclear Storage Overpack Door Actuator and Alignment Apparatus
Andreyko, Gregory M.
2005-05-11
The invention is a door actuator and alignment apparatus for opening and closing the 15,000-pound horizontally sliding door of a storage overpack. The door actuator includes a ball screw mounted horizontally on a rigid frame including a pair of door panel support rails. An electrically powered ball nut moves along the ball screw. The ball nut rotating device is attached to a carriage. The carriage attachment to the sliding door is horizontally pivoting. Additional alignment features include precision cam followers attached to the rails and rail guides attached to the carriage.
Nuclear storage overpack door actuator and alignment apparatus
Andreyko, Gregory M.
2005-05-10
The invention is a door actuator and alignment apparatus for opening and closing the 15,000-pound horizontally sliding door of a storage overpack. The door actuator includes a ball screw mounted horizontally on a rigid frame including a pair of door panel support rails. An electrically powered ball nut moves along the ball screw. The ball nut rotating device is attached to a carriage. The carriage attachment to the sliding door is horizontally pivoting. Additional alignment features include precision cam followers attached to the rails and rail guides attached to the carriage.
NASA Astrophysics Data System (ADS)
Borcherds, P. H.
2004-09-01
There is a new tradition in England called Apple Day which is held on some day in October. The actual day varies from place to place. For instance, in 2003, 23 October was Apple Day at Woolsthorpe Manor, the house where Isaac Newton was born and where, during the Plague, he is said to have developed the theory of gravity. (For information on future Apple Days see, for example, http://www.nationaltrust.org.uk/main/thingstodo.) Last year in our garden we picked an apple which weighed one pound, thirteen and a half ounces (1 lb 13 1/2 oz or 29 1/2 oz). The following day we went to an Apple Day event where there were many exotic apples on display, varieties which are not sold in shops. One of the varieties there was called 'Twenty Ounce'. By now you may be wondering what all this has to do with the book being reviewed. We shall return to this later. This entertaining book is ostensibly about units, in particular about Imperial and metric units, but there are numerous informative digressions. The author reminds us that almost every country 'with the exception of the United States, North and South Yemen, Burma and Brunei' has gone metric. He points out that the United States (US) became officially metric in 1893. However, as early as 1866, the US legal definition of the metre was 39.370000 inches. He tells us that after World War II the (US) inch was rounded down (from 25.400051) to 25.4 mm. There is no mention that the Imperial (British) inch was simultaneously rounded up from 25.399956 mm to 25.4 mm. The author frequently digresses, covering such matters as the trisection of angles and Eratosthenes' graphic solution for duplicating the cube. There is an informative discussion on the length of the day: appropriately 25 December, which lasts for 24 h and 30 s, is the longest day. He shows how with cycles and epicycles one can construct an ellipse. Ptolemy did not realize the importance of the focus of the ellipse. The author discusses various topics in the development of physics and of the industrial revolution, much of which took place not very far from where I am writing. We are reminded of James Watt (whose firm, Boulton and Watt, was in Birmingham) and his invention of the horsepower (HP). My slide-rule cursor has a special mark for 746 (watt/HP). We are reminded of the powers of 10 prefixes in the metric system, and of the importance of distinguishing upper case M, 106, from lower case m, 10-3. This distinction appears not to be very well known to journalists, who regularly report on new power stations which are capable of producing nearly as much power as a torch battery. Let us now return to our apples. The SI unit of force is the Newton, which is very appropriate since the Newton is about the weight of an average apple. Not of course the weight of a Twenty Ounce apple, whose weight is about 5 N. In the preface there is an implicit reminder that many English proverbs and figures of speech make use of Imperial units. My impression is that some of the countries of the British Commonwealth, when they went metric, did everything they could to eliminate all mention of Imperial units. (Referring to Imperial units has not been made a hanging offence, but perhaps that is because the death penalty has been abolished.) Do they now say 'A miss is as good as 1.6 kilometres' or is it rounded down to 'a kilometre'? In the course of a survey of obsolescent units we are reminded of the guinea (21 shillings = £1.05). In horse-racing, at least, it is not yet obsolete: there are classic races still called the Thousand Guineas and the Two Thousand Guineas, but no doubt the Brussels Eurocrats would like to call them the Thousand and Fifty Pounds or the One Thousand Seven Hundred and Forty-Three Euros, and will in due course prosecute someone if the names are not changed into Eurospeak. The final section of the book is entitled 'The global vision: illusion or reality'. In this the author calls for a unified system of units. But we already have one: SI provides just that. It is highly desirable that nuts and bolts and other components have standardized sizes. When I was a student there were numerous British Standard (BS) sizes for nuts and bolts, including British Standard Whitworth (BSW), British Standard Fine (BSF), British Standard Pipe (still used, I think), British Association (BA), as well as American sizes (in inches) and continental sizes (metric). This could be a nuisance when your car loses a nut in a foreign country. There is clearly a great advantage in having a common international standard for components. Incidentally, the BA standard, dating back to the mid 19th century, was a metric standard: the largest bolt, 0 BA, is 6 mm diameter; the other sizes are logarithmically related. I can really see no merit in forcing everyone to use the same unit names. If I prefer to use pounds and ounces and you to use grams and kilograms, this is no real inconvenience to anyone. My motor car has an onboard computer which allows me to choose whether to show fuel consumption etc in Imperial or metric units and I have recently bought a digital thermometer which allows me to choose between the two centigrade systems, invented by Fahrenheit and Celsius. The author himself suggests a new temperature scale with the degree denoted by °H. He does not give a name to his new scale; possibly it is Hebra? As readers will have gathered, I have enjoyed reading and reviewing this book, and I recommend it to readers of European Journal of Physics for their erudition and entertainment. It is not intended as a textbook, but you will find in it some anecdotes and examples with which to enliven your lectures. Either buy it for yourself, or drop hints to your family that it would make a suitable present (to give to you), and recommend it to your librarian. Long live the Twenty Ounce apple!
NASA Astrophysics Data System (ADS)
Ahmed, Ali
2017-03-01
Finite element (FE) analyses were performed to explore the prying influence on moment-rotation behaviour and to locate yielding zones of top- and seat-angle connections in author's past research studies. The results of those FE analyses with experimental failure strategies of the connections were used to develop failure mechanisms of top- and seat-angle connections in the present study. Then a formulation was developed based on three simple failure mechanisms considering bending and shear deformations, effects of prying action on the top angle and stiffness of the tension bolts to estimate rationally the ultimate moment M u of the connection, which is a vital parameter of the proposed four-parameter power model. Applicability of the proposed formulation is assessed by comparing moment-rotation ( M- θ r ) curves and ultimate moment capacities with those measured by experiments and estimated by FE analyses and three-parameter power model. This study shows that proposed formulation and Kishi-Chen's method both achieved close approximation driving M- θ r curves of all given connections except a few cases of Kishi-Chen model, and M u estimated by the proposed formulation is more rational than that predicted by Kishi-Chen's method.
NASA Technical Reports Server (NTRS)
Long, M. J.
1983-01-01
"Built-in" gage determines whether large bolt or stud has been torqued to desired load and provides for continuous inspection to ensure proper load is being maintained. Gage detects longitudinal stress/strain bolt; requires no electronic or sonic test equipment.
B. E. Carpenter
1959-01-01
But how about bolts from cull oaks on upland pine sites? Though a bolt operation in such material offers many difficulties, at least one Southern firm is currently trying it. That firm is Potlatch Forests, Inc., of Warren, Arkansas.
Evaluation of Rock Bolt Support for Polish Hard Rock Mines
NASA Astrophysics Data System (ADS)
Skrzypkowski, Krzysztof
2018-03-01
The article presents different types of rock bolt support used in Polish ore mining. Individual point resin and expansion rock bolt support were characterized. The roof classes for zinc and lead and copper ore mines were presented. Furthermore, in the article laboratory tests of point resin rock bolt support in a geometric scale of 1:1 with minimal fixing length of 0.6 m were made. Static testing of point resin rock bolt support were carried out on a laboratory test facility of Department of Underground Mining which simulate mine conditions for Polish ore and hard coal mining. Laboratory tests of point resin bolts were carried out, especially for the ZGH Bolesław, zinc and lead "Olkusz - Pomorzany" mine. The primary aim of the research was to check whether at the anchoring point length of 0.6 m by means of one and a half resin cartridge, the type bolt "Olkusz - 20A" is able to overcome the load.The second purpose of the study was to obtain load - displacement characteristic with determination of the elastic and plastic range of the bolt. For the best simulation of mine conditions the station steel cylinders with an external diameter of 0.1 m and a length of 0.6 m with a core of rock from the roof of the underground excavations were used.
75 FR 13682 - Airworthiness Directives; Bombardier, Inc. Model DHC-8-400 Series Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-23
... retention bolt, a reverse orientation of the retention bolt and a rework of the weight on wheel (WOW... reverse orientation of the retention bolt and a rework of the weight on wheel (WOW) proximity sensor cover...
Square cants from round bolts without slabs or sawdust
Peter Koch
1960-01-01
For maximum efficiency a headrig for converting bark-free bolts into cants must (1) have a fast cycle time, (2) require minimum handling of bolts and refuse, and (3) convert the volume represented by slabs and kerf into a salable byproduct.
Explosive Bolt Dual-Initiated from One Side
NASA Technical Reports Server (NTRS)
Snow, Eric
2011-01-01
An explosive bolt has been developed that has a one-sided dual initiation train all the way down to the pyro charge for high reliability, while still allowing the other side of the bolt to remain in place after actuation to act as a thermal seal in an extremely high-temperature environment. This lightweight separation device separates at a single fracture plane, and has as much redundancy/reliability as possible. The initiation train comes into the explosive bolt from one side.
Easing The Calculation Of Bolt-Circle Coordinates
NASA Technical Reports Server (NTRS)
Burley, Richard K.
1995-01-01
Bolt Circle Calculation (BOLT-CALC) computer program used to reduce significant time consumed in manually computing trigonometry of rectangular Cartesian coordinates of holes in bolt circle as shown on blueprint or drawing. Eliminates risk of computational errors, particularly in cases involving many holes or in cases in which coordinates expressed to many significant digits. Program assists in many practical situations arising in machine shops. Written in BASIC. Also successfully compiled and implemented by use of Microsoft's QuickBasic v4.0.
Williams, Gary L.; Goin, Jr., Jesse L.; Kirby, Patrick G.; McKenna, John P.
1997-01-01
The invention is a motorized linkage for operating a door strike. A six volt power source, controlled by a security code, rotates a small electric motor when a proper security code is given. The motor rotates a shaft which engages a coil spring. This moves a locking cam. When a catch on the locking cam separates from the locking lever catch, the latch bolt keeper may be manipulated by a user.
Evidence for a pheromone in the locust borer
Jimmy R. Galford
1977-01-01
Laboratory studies have suggested the existence of a pheromone in the locust borer. Male beetles spent more time on bolts of wood exposed to virgin females than on control bolts. The females apparently deposited the pheromone on the bolts of wood and filter paper.
A Method to Capture Macroslip at Bolted Interfaces
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hopkins, Ronald Neil; Heitman, Lili Anne Akin
2015-10-01
Relative motion at bolted connections can occur for large shock loads as the internal shear force in the bolted connection overcomes the frictional resistive force. This macroslip in a structure dissipates energy and reduces the response of the components above the bolted connection. There is a need to be able to capture macroslip behavior in a structural dynamics model. A linear model and many nonlinear models are not able to predict marcoslip effectively. The proposed method to capture macroslip is to use the multi-body dynamics code ADAMS to model joints with 3-D contact at the bolted interfaces. This model includesmore » both static and dynamic friction. The joints are preloaded and the pinning effect when a bolt shank impacts a through hole inside diameter is captured. Substructure representations of the components are included to account for component flexibility and dynamics. This method was applied to a simplified model of an aerospace structure and validation experiments were performed to test the adequacy of the method.« less
Load apparatus and method for bolt-loaded compact tension test specimen
Buescher, B.J. Jr.; Lloyd, W.R.; Ward, M.B.; Epstein, J.S.
1997-02-04
A bolt-loaded compact tension test specimen load apparatus includes: (a) a body having first and second opposing longitudinal ends, the first end comprising an externally threaded portion sized to be threadedly received within the test specimen threaded opening; (b) a longitudinal loading rod having first and second opposing longitudinal ends, the loading rod being slidably received in a longitudinal direction within the body internally through the externally threaded portion and slidably extending longitudinally outward of the body first longitudinal end; (c) a force sensitive transducer slidably received within the body and positioned to engage relative to the loading rod second longitudinal end; and (d) a loading bolt threadedly received relative to the body, the loading bolt having a bearing end surface and being positioned to bear against the transducer to forcibly sandwich the transducer between the loading bolt and loading rod. Also disclosed is a method of in situ determining applied force during crack propagation in a bolt-loaded compact tension test specimen. 6 figs.
Load apparatus and method for bolt-loaded compact tension test specimen
Buescher, Jr., Brent J.; Lloyd, W. Randolph; Ward, Michael B.; Epstein, Jonathan S.
1997-01-01
A bolt-loaded compact tension test specimen load apparatus includes: a) a body having first and second opposing longitudinal ends, the first end comprising an externally threaded portion sized to be threadedly received within the test specimen threaded opening; b) a longitudinal loading rod having first and second opposing longitudinal ends, the loading rod being slidably received in a longitudinal direction within the body internally through the externally threaded portion and slidably extending longitudinally outward of the body first longitudinal end; c) a force sensitive transducer slidably received within the body and positioned to engage relative to the loading rod second longitudinal end; and d) a loading bolt threadedly received relative to the body, the loading bolt having a bearing end surface and being positioned to bear against the transducer to forcibly sandwich the transducer between the loading bolt and loading rod. Also disclosed is a method of in situ determining applied force during crack propagation in a bolt-loaded compact tension test specimen.
NASA Astrophysics Data System (ADS)
Kim, S. Y.; Yoo, J. H.; Kim, H. K.; Shin, K. Y.; Yoon, S. J.
2018-06-01
In this paper, we discussed the structural behavior of bolted lap-joint connections in pultruded FRP structural members. Especially, bolted connections in pultruded FRP members are investigated for their failure modes and strength. Specimens with single and multiple bolt-holes are tested in tension under bolt-loading conditions. All of the specimens are instrumented with strain gages and the load-strain responses are monitored. The failed specimens are examined for the cracks and failure patterns. The purpose of this paper is to predict the failure strength by using the ratio of the results obtained by the experiment and the finite element analysis. In the study, several tests are conducted to determine the mechanical properties of pultruded FRP materials before the main experiment. The results are used in the finite element analysis for single and multiple bolted lap-joint specimens. The results obtained by the experiment are compared with the results obtained by the finite element analysis.
Inflorescence Development and the Role of LsFT in Regulating Bolting in Lettuce (Lactuca sativa L.).
Chen, Zijing; Han, Yingyan; Ning, Kang; Ding, Yunyu; Zhao, Wensheng; Yan, Shuangshuang; Luo, Chen; Jiang, Xiaotang; Ge, Danfeng; Liu, Renyi; Wang, Qian; Zhang, Xiaolan
2017-01-01
Lettuce ( Lactuca sativa L.) is one of the most important leafy vegetable that is consumed during its vegetative growth. The transition from vegetative to reproductive growth is induced by high temperature, which has significant economic effect on lettuce production. However, the progression of floral transition and the molecular regulation of bolting are largely unknown. Here we morphologically characterized the inflorescence development and functionally analyzed the FLOWERING LOCUS T (LsFT) gene during bolting regulation in lettuce. We described the eight developmental stages during floral transition process. The expression of LsFT was negatively correlated with bolting in different lettuce varieties, and was promoted by heat treatment. Overexpression of LsFT could recover the late-flowering phenotype of ft-2 mutant. Knockdown of LsFT by RNA interference dramatically delayed bolting in lettuce, and failed to respond to high temperature. Therefore, this study dissects the process of inflorescence development and characterizes the role of LsFT in bolting regulation in lettuce.
Inflorescence Development and the Role of LsFT in Regulating Bolting in Lettuce (Lactuca sativa L.)
Chen, Zijing; Han, Yingyan; Ning, Kang; Ding, Yunyu; Zhao, Wensheng; Yan, Shuangshuang; Luo, Chen; Jiang, Xiaotang; Ge, Danfeng; Liu, Renyi; Wang, Qian; Zhang, Xiaolan
2018-01-01
Lettuce (Lactuca sativa L.) is one of the most important leafy vegetable that is consumed during its vegetative growth. The transition from vegetative to reproductive growth is induced by high temperature, which has significant economic effect on lettuce production. However, the progression of floral transition and the molecular regulation of bolting are largely unknown. Here we morphologically characterized the inflorescence development and functionally analyzed the FLOWERING LOCUS T (LsFT) gene during bolting regulation in lettuce. We described the eight developmental stages during floral transition process. The expression of LsFT was negatively correlated with bolting in different lettuce varieties, and was promoted by heat treatment. Overexpression of LsFT could recover the late-flowering phenotype of ft-2 mutant. Knockdown of LsFT by RNA interference dramatically delayed bolting in lettuce, and failed to respond to high temperature. Therefore, this study dissects the process of inflorescence development and characterizes the role of LsFT in bolting regulation in lettuce. PMID:29403510
Sleeve Expansion of Bolt Holes in Railroad Rail : Volume II, Process Parameters and Procedures
DOT National Transportation Integrated Search
1980-02-01
The bolt-hole cold-expansion process has been applied to railroad rail in laboratory tests and has demonstrated a potential for the reduction of rail-bolt-hole-failure incidence. Limited field tests also have been conducted and are currently under lo...
ERIC Educational Resources Information Center
Scott, Alan
2013-01-01
A simple apparatus is described which serves as a materials testing laboratory. Bolts are placed in it and subjected to tensile and torsional stress while being tightened. The tensile and torsional stress and strain can be measured, which enables the determination of several mechanical properties of the bolt material, including Young's…
Code of Federal Regulations, 2011 CFR
2011-10-01
... replaced. (d) Each rail shall be bolted with at least two bolts at each joint. (e) Each joint bar shall be... in this subpart. (f) No rail shall have a bolt hole which is torch cut or burned. (g) No joint bar shall be reconfigured by torch cutting. ...
46 CFR 98.30-27 - Connections.
Code of Federal Regulations, 2014 CFR
2014-10-01
... other hole and in no case less than four bolts in each temporary connection utilizing an American National Standards Institute (ANSI) standard flange coupling; (3) Use a bolt in each hole of couplings other than ANSI standard flange couplings; (4) Use a bolt in each hole of each permanently connected...
49 CFR 231.17 - Specifications common to all steam locomotives.
Code of Federal Regulations, 2011 CFR
2011-10-01
... shall be securely fastened with bolts, rivets, or studs. (ii) Locomotives having Wootten type boilers... inches above outside edge of running boards, securely fastened with bolts, rivets, or studs. (c... inches in height, measured from the top of end sill, and securely fastened with bolts or rivets. (f...
77 FR 29212 - Airworthiness Directives; The Boeing Company Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-17
... Company Model 777 airplanes. This AD was prompted by reports of fractured and missing latch pin retention... inspections for fractured or missing latch pin retention bolts, replacement of existing titanium bolts with... AD to detect and correct fractured and missing latch pin retention bolts, which could result in...
Calculation of parameters of combined frame and roof bolting
NASA Astrophysics Data System (ADS)
Ivanov, S. I.; Titov, N. V.; Privalov, A. A.; Trunov, I. T.; Sarychev, V. I.
2017-10-01
The paper presents the method of calculation of the combined frame and roof bolting. Recommendations on providing joint operation of roof bolting with steel support frames are given. Graphs for determining standard rock movement, as well as for defining proof load on the yielding support, were developed.
77 FR 40828 - Airworthiness Directives; The Boeing Company Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2012-07-11
... certain main landing gear (MLG) upper torque link bolts is reduced significantly due to incorrect fabrication. This proposed AD would require replacing certain MLG upper torque link bolts with a new or... safe life limit on certain MLG upper torque link bolts is reduced significantly due to incorrect...
46 CFR 56.90-5 - Bolting procedure.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 46 Shipping 2 2010-10-01 2010-10-01 false Bolting procedure. 56.90-5 Section 56.90-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PIPING SYSTEMS AND APPURTENANCES Assembly § 56.90-5 Bolting procedure. (a) All flanged joints shall be fitted up so that the gasket...
Torquing preload in a lubricated bolt
NASA Technical Reports Server (NTRS)
Seegmiller, H. L.
1978-01-01
The tension preload obtained by torquing a 7/8 in. diam UNC high strength bolt was determined for lubricated and dry conditions. Consistent preload with a variation of + or - 3% was obtained when the bolt head area was lubricated prior to each torque application. Preload tensions nearly 70% greater than the value predicted with the commonly used formula occurred with the lubricated bolt. A reduction to 39% of the initial preload was observed during 50 torque applications without relubrication. Little evidence of wear was noted after 203 cycles of tightening.
Cheng, Liang; Zhang, Yidong; Ji, Ming; Zhang, Kai; Zhang, Minglei
2016-01-01
Roadways supported by bolts contain support structures that are built into the rock surrounding the roadway, referred to as reinforced rocks in this paper. Using physical model simulation, the paper investigates the bearing characteristics of the reinforced rock under different bolt parameters with incrementally increased load. The experimental results show that the stress at the measurement point inside the structure varies with the kinetic pressure. The stress increases slowly as the load is initially applied, displays accelerated growth in the middle of the loading application, and decreases or remains constant in the later stage of the loading application. The change in displacement of the surrounding rock exhibits the following characteristics: a slow increase when the load is first applied, accelerated growth in the middle stage, and violent growth in the later stage. There is a good correlation between the change in the measured stress and the change in the surrounding rock displacement. Increasing the density of the bolt support and the length and diameter of the bolt improves the load-bearing performance of the reinforced rock, including its strength, internal peak stress, and residual stress. Bolting improves the internal structure of the surrounding rocks, and the deterioration of the surrounding rock decreases with the distance between the bolt supports.
Accidental Bolt Gun Injury to Femur - A Case Report.
Kattimani, Ravi Prasad; Shetty, Sanath; Mirza, Humayun
2016-01-01
Bolt gun or slaughterer's guns are used in meat industry for "humane killing" of animals. Injuries caused by bolt gun are rare, reported exclusively from central European countries. We report a case of 28 year old male, who accidentally shot himself with a bolt gun to his right thigh. A 28 years old male presented to our Accident and Emergency department after accidental injury to his right thigh with bolt gun. He had an entry wound measuring 2 cm in length and 1 cm in breadth over anterior aspect of lower one third of thigh at lower and sustained Grade II compound fracture of right femur shaft at distal one third. The wound was treated with multiple debridements, negative pressure wound therapy and intravenous antibiotics based on culture and sensitivity. Bolt gun or slaughterer's guns are weapons used in meat industry for slaughtering animals. Wounds inflicted by bolt guns have specific morphological feature, distinctive from wounds made by other kinds of hand firearms. Most of the time wound will be infected at presentation. Lesions caused by these weapons are likely to have a more serious character than is to be expected from the size of the entrance wound. The mainstay of treatment is liberal wound exploration, multiple debridement's and intra venous antibiotics based on culture reports to treat infection and prevent morbidity.
Linear Back-Drive Differentials
NASA Technical Reports Server (NTRS)
Waydo, Peter
2003-01-01
Linear back-drive differentials have been proposed as alternatives to conventional gear differentials for applications in which there is only limited rotational motion (e.g., oscillation). The finite nature of the rotation makes it possible to optimize a linear back-drive differential in ways that would not be possible for gear differentials or other differentials that are required to be capable of unlimited rotation. As a result, relative to gear differentials, linear back-drive differentials could be more compact and less massive, could contain fewer complex parts, and could be less sensitive to variations in the viscosities of lubricants. Linear back-drive differentials would operate according to established principles of power ball screws and linear-motion drives, but would utilize these principles in an innovative way. One major characteristic of such mechanisms that would be exploited in linear back-drive differentials is the possibility of designing them to drive or back-drive with similar efficiency and energy input: in other words, such a mechanism can be designed so that a rotating screw can drive a nut linearly or the linear motion of the nut can cause the screw to rotate. A linear back-drive differential (see figure) would include two collinear shafts connected to two parts that are intended to engage in limited opposing rotations. The linear back-drive differential would also include a nut that would be free to translate along its axis but not to rotate. The inner surface of the nut would be right-hand threaded at one end and left-hand threaded at the opposite end to engage corresponding right- and left-handed threads on the shafts. A rotation and torque introduced into the system via one shaft would drive the nut in linear motion. The nut, in turn, would back-drive the other shaft, creating a reaction torque. Balls would reduce friction, making it possible for the shaft/nut coupling on each side to operate with 90 percent efficiency.
An analysis of roof bolter fatalities and injuries in U.S. mining
Sammarco, J.J.; Podlesny, A.; Rubinstein, E.N.; Demich, B.
2017-01-01
Roof bolting typically follows the extraction of a commodity to help keep the roof from collapsing. During 2004 to 2013, roof bolter operators had the highest number of machinery-related injuries, accounting for 64.7 percent, at underground coal mines. This paper analyzes U.S. roof bolter fatal and nonfatal lost-time injury data at underground work locations for all commodities from 2004 through 2013 and determines risk indices for six roof bolting tasks. For fatal and nonfatal incidences combined, the roof bolting tasks in order of the highest to lowest risk index were bolting, handling of materials, setting the temporary roof support (TRS), drilling, tramming, and traversing. For fatalities, the roof bolting tasks in order of the highest to lowest risk index were handling of materials, setting the TRS, bolting, drilling, traversing, and tramming. Age was found to be a significant factor. Severity of injury, indicated by days lost, was found to increase with increasing age as well as with increasing experience, largely due to the confounding of age and experience. The operation of the roof bolting machine used in underground mining should be a research priority given the high frequency and severity of incidents. The results also suggest that temporal factors may exist, so additional research is warranted to better understand these factors and potentially develop interventions. This research provides a data-driven foundation from which future research can be conducted for safety interventions to reduce the frequency and severity of incidences involving the roof bolter activities of bolting, handling of materials, and setting the TRS. PMID:28845099
Lawrence A. Soltis; Thomas Lee Wilkinson
1987-01-01
Recent failures of bolted connections have raised doubts about our knowledge of their design. Some of the design criteria are based on research conducted more than 50 years ago. This paper compares results found in the literature, using the European Yield Theory as a basis of comparison, to summarize what is known about bolted-connection design and what needs further...
46 CFR 98.30-27 - Connections.
Code of Federal Regulations, 2013 CFR
2013-10-01
... joints and couplings to make a tight seal; (2) Use a bolt in at least every other hole and in no case... (ANSI) standard flange coupling; (3) Use a bolt in each hole of couplings other than ANSI standard flange couplings; (4) Use a bolt in each hole of each permanently connected flange coupling; (5) Use...
46 CFR 98.30-27 - Connections.
Code of Federal Regulations, 2011 CFR
2011-10-01
... joints and couplings to make a tight seal; (2) Use a bolt in at least every other hole and in no case... (ANSI) standard flange coupling; (3) Use a bolt in each hole of couplings other than ANSI standard flange couplings; (4) Use a bolt in each hole of each permanently connected flange coupling; (5) Use...
46 CFR 98.30-27 - Connections.
Code of Federal Regulations, 2012 CFR
2012-10-01
... joints and couplings to make a tight seal; (2) Use a bolt in at least every other hole and in no case... (ANSI) standard flange coupling; (3) Use a bolt in each hole of couplings other than ANSI standard flange couplings; (4) Use a bolt in each hole of each permanently connected flange coupling; (5) Use...
Multiple-bolted joints in wood members : a literature review
Peter James Moss
1997-01-01
This study reviewed the literature on experimental and analytical research for the connection of wood members using multiple laterally loaded bolts. From this, the influence of geometric factors were ascertained, such as staggered and aligned fasteners, optimum fastener configurations, row factors and length-to-diameter bolt ratios, spacing, end and edge distances, and...