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Sample records for liquid relief valves

  1. 40 CFR 60.482-8 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... liquid service, pressure relief devices in light liquid or heavy liquid service, and connectors. 60.482-8... Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or heavy liquid... any other detection method at pumps and valves in heavy liquid service, pressure relief devices...

  2. 40 CFR 60.482-8 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... liquid service, pressure relief devices in light liquid or heavy liquid service, and connectors. 60.482-8... Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or heavy liquid... any other detection method at pumps and valves in heavy liquid service, pressure relief devices...

  3. 40 CFR 60.482-8 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... liquid service, pressure relief devices in light liquid or heavy liquid service, and connectors. 60.482-8... Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or heavy liquid... any other detection method at pumps and valves in heavy liquid service, pressure relief devices...

  4. 40 CFR 60.482-8 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... liquid service, pressure relief devices in light liquid or heavy liquid service, and connectors. 60.482-8... Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or heavy liquid... any other detection method at pumps and valves in heavy liquid service, pressure relief devices...

  5. 40 CFR 60.482-8 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... liquid service, pressure relief devices in light liquid or heavy liquid service, and connectors. 60.482-8... Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or heavy liquid... any other detection method at pumps and valves in heavy liquid service, pressure relief devices...

  6. Vent Relief Valve Test

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Shown is the disassembly, examination, refurbishment and testing of the LH2 ( liquid hydrogen) and LOX (liquid oxygen) vent and relief valves for the S-IVB-211 engine stage in support of the Constellation/Ares project. This image is extracted from high definition video and is the highest resolution available.

  7. 40 CFR 63.1029 - Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief devices in...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation systems... million or greater for valves, connectors, instrumentation systems, and pressure relief devices is... soap solution; or that the system will hold a test pressure. ...

  8. Liquid rocket pressure regulators, relief valves, check valves, burst disks, and explosive valves. [design techniques and practices

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The development of and operational programs for effective use in design are presented for liquid rocket pressure regulators, relief valves, check valves, burst disks, and explosive valves. A review of the total design problem is presented, and design elements are identified which are involved in successful design. Current technology pertaining to these elements is also described. Design criteria are presented which state what rule or standard must be imposed on each essential design element to assure successful design. These criteria serve as a checklist of rules for a project manager to use in guiding a design or in assessing its adequacy. Recommended practices are included which state how to satisfy each of the criteria.

  9. 40 CFR 63.1010 - Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief devices in...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation systems... (CONTINUED) National Emission Standards for Equipment Leaks-Control Level 1 § 63.1010 Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and...

  10. 40 CFR 60.482-8a - Standards: Pumps, valves, and connectors in heavy liquid service and pressure relief devices in...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... connectors in heavy liquid service and pressure relief devices in light liquid or heavy liquid service. 60... connectors in heavy liquid service and pressure relief devices in light liquid or heavy liquid service. (a... at pumps, valves, and connectors in heavy liquid service and pressure relief devices in light...

  11. 40 CFR 60.482-8a - Standards: Pumps, valves, and connectors in heavy liquid service and pressure relief devices in...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... connectors in heavy liquid service and pressure relief devices in light liquid or heavy liquid service. 60... connectors in heavy liquid service and pressure relief devices in light liquid or heavy liquid service. (a... at pumps, valves, and connectors in heavy liquid service and pressure relief devices in light...

  12. 40 CFR 60.482-8a - Standards: Pumps, valves, and connectors in heavy liquid service and pressure relief devices in...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... connectors in heavy liquid service and pressure relief devices in light liquid or heavy liquid service. 60... connectors in heavy liquid service and pressure relief devices in light liquid or heavy liquid service. (a... at pumps, valves, and connectors in heavy liquid service and pressure relief devices in light...

  13. 40 CFR 60.482-8a - Standards: Pumps, valves, and connectors in heavy liquid service and pressure relief devices in...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... connectors in heavy liquid service and pressure relief devices in light liquid or heavy liquid service. 60... connectors in heavy liquid service and pressure relief devices in light liquid or heavy liquid service. (a... at pumps, valves, and connectors in heavy liquid service and pressure relief devices in light...

  14. 40 CFR 60.482-8a - Standards: Pumps, valves, and connectors in heavy liquid service and pressure relief devices in...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... connectors in heavy liquid service and pressure relief devices in light liquid or heavy liquid service. 60... connectors in heavy liquid service and pressure relief devices in light liquid or heavy liquid service. (a... at pumps, valves, and connectors in heavy liquid service and pressure relief devices in light...

  15. Hydrogen gas relief valve

    DOEpatents

    Whittlesey, Curtis C.

    1985-01-01

    An improved battery stack design for an electrochemical system having at least one cell from which a gas is generated and an electrolyte in communication with the cell is described. The improved battery stack design features means for defining a substantially closed compartment for containing the battery cells and at least a portion of the electrolyte for the system, and means in association with the compartment means for selectively venting gas from the interior of the compartment means in response to the level of the electrolyte within the compartment means. The venting means includes a relief valve having a float member which is actuated in response to the level of the electrolyte within the compartment means. This float member is adapted to close the relief valve when the level of the electrolyte is above a predetermined level and open the relief valve when the level of electrolyte is below this predetermined level.

  16. 46 CFR 105.10-20 - Pressure vacuum relief valve.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Pressure vacuum relief valve. 105.10-20 Section 105.10... Pressure vacuum relief valve. (a) The term pressure vacuum relief valve means any device or assembly of a mechanical, liquid, weight, or other type used for the automatic regulation of pressure or vacuum in...

  17. 46 CFR 105.10-20 - Pressure vacuum relief valve.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Pressure vacuum relief valve. 105.10-20 Section 105.10... Pressure vacuum relief valve. (a) The term pressure vacuum relief valve means any device or assembly of a mechanical, liquid, weight, or other type used for the automatic regulation of pressure or vacuum in...

  18. 46 CFR 105.10-20 - Pressure vacuum relief valve.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Pressure vacuum relief valve. 105.10-20 Section 105.10... Pressure vacuum relief valve. (a) The term pressure vacuum relief valve means any device or assembly of a mechanical, liquid, weight, or other type used for the automatic regulation of pressure or vacuum in...

  19. 46 CFR 105.10-20 - Pressure vacuum relief valve.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Pressure vacuum relief valve. 105.10-20 Section 105.10... Pressure vacuum relief valve. (a) The term pressure vacuum relief valve means any device or assembly of a mechanical, liquid, weight, or other type used for the automatic regulation of pressure or vacuum in...

  20. 46 CFR 105.10-20 - Pressure vacuum relief valve.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Pressure vacuum relief valve. 105.10-20 Section 105.10... Pressure vacuum relief valve. (a) The term pressure vacuum relief valve means any device or assembly of a mechanical, liquid, weight, or other type used for the automatic regulation of pressure or vacuum in...

  1. 46 CFR 154.519 - Piping relief valves.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Piping relief valves. 154.519 Section 154.519 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS... Process Piping Systems § 154.519 Piping relief valves. (a) The liquid relief valve that protects the cargo...

  2. Fluid relief and check valve

    DOEpatents

    Blaedel, K.L.; Lord, S.C.; Murray, I.

    1986-07-17

    A passive fluid pressure relief and check valve allows the relief pressure to be slaved to a reference pressure independently of the exhaust pressure. The pressure relief valve is embodied by a submerged vent line in a sealing fluid, the relief pressure being a function of the submerged depth. A check valve is embodied by a vertical column of fluid (the maximum back pressure being a function of the height of the column of fluid). The pressure is vented into an exhaust system which keeps the exhaust out of the area providing the reference pressure.

  3. 100. INTERIOR OF SKID 9A: VENT VALVE AND RELIEF VALVE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    100. INTERIOR OF SKID 9A: VENT VALVE AND RELIEF VALVE FOR RAPID-LOAD LIQUID OXYGEN TANK - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  4. Improve safety with pilot operated relief valves

    SciTech Connect

    Emerson, G.

    1996-10-01

    A weakness inherent in balanced bellows pressure relief valves (PRVs) that can cause premature failure can be avoided by using pilot operated PRVs as an alternative. Now better able to handle adverse service conditions, pilot operated PRVs are suitable for a wide range of gas, liquid and mixed-phase services. Traditionally, however, balanced bellows PRVs have been applied as overpressure protection for three notable reasons: a constant PRV set pressure with the presence of variable, superimposed back pressure (at the PRV outlet prior to its opening); valve stability and adequate capacity when built-up back pressure (at the PRV outlet during its relief cycle) exceeds 10%; and spring and guided parts barriered from the process fluid. With these benefits in mind, balanced bellows PRVs have been generally adapted by many hydrocarbon processing companies that have experienced costly, and often dangerous, premature bellows failures. Corrosion, valve instability and/or bellows flutter are causes of these failures.

  5. Statistical Performance Evaluation Of Soft Seat Pressure Relief Valves

    SciTech Connect

    Harris, Stephen P.; Gross, Robert E.

    2013-03-26

    Risk-based inspection methods enable estimation of the probability of failure on demand for spring-operated pressure relief valves at the United States Department of Energy's Savannah River Site in Aiken, South Carolina. This paper presents a statistical performance evaluation of soft seat spring operated pressure relief valves. These pressure relief valves are typically smaller and of lower cost than hard seat (metal to metal) pressure relief valves and can provide substantial cost savings in fluid service applications (air, gas, liquid, and steam) providing that probability of failure on demand (the probability that the pressure relief valve fails to perform its intended safety function during a potentially dangerous over pressurization) is at least as good as that for hard seat valves. The research in this paper shows that the proportion of soft seat spring operated pressure relief valves failing is the same or less than that of hard seat valves, and that for failed valves, soft seat valves typically have failure ratios of proof test pressure to set pressure less than that of hard seat valves.

  6. Aspirator increases relief valve poppet stroke

    NASA Technical Reports Server (NTRS)

    Biddle, M. E.

    1967-01-01

    Addition of an aspirator to a relief valve increases the valve poppet stroke under dynamic flow conditions. The aspirator allows poppet inlet dynamic forces to overcome relief valve spring force. It reduces the fluid pressure in the skirt cavity by providing a low pressure sense probe.

  7. How back pressure affects safety relief valves

    SciTech Connect

    Papa, D.M.

    1983-05-01

    The prefered valve types to reduce back pressure are the pilot operated valve, the balanced direct spring valve, and the conventional direct spring valve. Back pressure (static pressure at the outlet when the valve is closed), superimposed back pressure, and built up back pressure are defined. The relief characteristics of the pilot, balanced, and direct spring valves are schematicized. Typical safety valve operations are outlined. Methods for sizing discharge piping to avoid piping pressure losses that produce excessive back pressure are recommended. The guidelines discussed improve overpressure protection.

  8. 49 CFR 179.400-21 - Test of pressure relief valves.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... CARS Specification for Cryogenic Liquid Tank Car Tanks and Seamless Steel Tanks (Classes DOT-113 and 107A) § 179.400-21 Test of pressure relief valves. Each valve must be tested with air or gas...

  9. 49 CFR 179.400-21 - Test of pressure relief valves.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... CARS Specification for Cryogenic Liquid Tank Car Tanks and Seamless Steel Tanks (Classes DOT-113 and 107A) § 179.400-21 Test of pressure relief valves. Each valve must be tested with air or gas...

  10. 49 CFR 179.400-21 - Test of pressure relief valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... CARS Specification for Cryogenic Liquid Tank Car Tanks and Seamless Steel Tanks (Classes DOT-113 and 107A) § 179.400-21 Test of pressure relief valves. Each valve must be tested with air or gas...

  11. 49 CFR 230.49 - Setting of safety relief valves.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Setting of safety relief valves. 230.49 Section... Appurtenances Safety Relief Valves § 230.49 Setting of safety relief valves. (a) Qualifications of individual who adjusts. Safety relief valves shall be set and adjusted by a competent person who is thoroughly...

  12. 49 CFR 230.49 - Setting of safety relief valves.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Setting of safety relief valves. 230.49 Section... Appurtenances Safety Relief Valves § 230.49 Setting of safety relief valves. (a) Qualifications of individual who adjusts. Safety relief valves shall be set and adjusted by a competent person who is...

  13. 49 CFR 230.49 - Setting of safety relief valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Setting of safety relief valves. 230.49 Section... Appurtenances Safety Relief Valves § 230.49 Setting of safety relief valves. (a) Qualifications of individual who adjusts. Safety relief valves shall be set and adjusted by a competent person who is...

  14. 49 CFR 230.49 - Setting of safety relief valves.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Setting of safety relief valves. 230.49 Section... Appurtenances Safety Relief Valves § 230.49 Setting of safety relief valves. (a) Qualifications of individual who adjusts. Safety relief valves shall be set and adjusted by a competent person who is...

  15. 49 CFR 230.49 - Setting of safety relief valves.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Setting of safety relief valves. 230.49 Section... Appurtenances Safety Relief Valves § 230.49 Setting of safety relief valves. (a) Qualifications of individual who adjusts. Safety relief valves shall be set and adjusted by a competent person who is...

  16. Liquid rocket valve components

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A monograph on valves for use with liquid rocket propellant engines is presented. The configurations of the various types of valves are described and illustrated. Design criteria and recommended practices for the various valves are explained. Tables of data are included to show the chief features of valve components in use on operational vehicles.

  17. Glovebox pressure relief and check valve

    SciTech Connect

    Blaedel, K.L.

    1986-03-17

    This device is a combined pressure relief valve and check valve providing overpressure protection and preventing back flow into an inert atmosphere enclosure. The pressure relief is embodied by a submerged vent line in a mercury reservior, the releif pressure being a function of the submerged depth. The pressure relief can be vented into an exhaust system and the relieving pressure is only slightly influenced by the varying pressure in the exhaust system. The check valve is embodied by a ball which floats on the mercury column and contacts a seat whenever vacuum exists within the glovebox enclosure. Alternatively, the check valve is embodied by a vertical column of mercury, the maximum back pressure being a function of the height of the column of mercury.

  18. 46 CFR 154.806 - Capacity of pressure relief valves.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Capacity of pressure relief valves. 154.806 Section 154... Equipment Cargo Vent Systems § 154.806 Capacity of pressure relief valves. Pressure relief valves for each cargo tank must have a combined relief capacity, including the effects of back pressure from vent...

  19. 46 CFR 154.806 - Capacity of pressure relief valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Capacity of pressure relief valves. 154.806 Section 154... Equipment Cargo Vent Systems § 154.806 Capacity of pressure relief valves. Pressure relief valves for each cargo tank must have a combined relief capacity, including the effects of back pressure from vent...

  20. 46 CFR 154.806 - Capacity of pressure relief valves.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Capacity of pressure relief valves. 154.806 Section 154... Equipment Cargo Vent Systems § 154.806 Capacity of pressure relief valves. Pressure relief valves for each cargo tank must have a combined relief capacity, including the effects of back pressure from vent...

  1. 46 CFR 154.806 - Capacity of pressure relief valves.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Capacity of pressure relief valves. 154.806 Section 154... Equipment Cargo Vent Systems § 154.806 Capacity of pressure relief valves. Pressure relief valves for each cargo tank must have a combined relief capacity, including the effects of back pressure from vent...

  2. 46 CFR 154.806 - Capacity of pressure relief valves.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Capacity of pressure relief valves. 154.806 Section 154... Equipment Cargo Vent Systems § 154.806 Capacity of pressure relief valves. Pressure relief valves for each cargo tank must have a combined relief capacity, including the effects of back pressure from vent...

  3. Refuge alternatives relief valve testing and design

    PubMed Central

    Lutz, T.J.; Bissert, P.T.; Homce, G.T.; Yonkey, J.A.

    2016-01-01

    The U.S. National Institute for Occupational Safety and Health (NIOSH) has been researching refuge alternatives (RAs) since 2007. RAs typically have built-in pressure relief valves (PRVs) to prevent the unit from reaching unsafe pressures. The U.S. Mine Safety and Health Administration requires that these valves vent the chamber at a maximum pressure of 1.25 kPa (0.18 psi, 5.0 in. H2O), or as specified by the manufacturer, above mine atmospheric pressure in the RA. To facilitate PRV testing, an instrumented benchtop test fixture was developed using an off-the-shelf centrifugal blower and ductwork. Relief pressures and flow characteristics were measured for three units: (1) a modified polyvinyl chloride check valve, (2) an off-the-shelf brass/cast-iron butterfly check valve and (3) a commercially available valve that was designed specifically for one manufacturer’s steel prefabricated RAs and had been adapted for use in one mine operator’s built-in-place RA. PRVs used in tent-style RAs were not investigated. The units were tested with different modifications and configurations in order to check compliance with Title 30 Code of Federal Regulations, or 30 CFR, regulations. The commercially available relief valve did not meet the 30 CFR relief pressure specification but may meet the manufacturer’s specification. Alternative valve designs were modified to meet the 30 CFR relief pressure specification, but all valve designs will need further design research to examine survivability in the event of a 103 kPa (15.0 psi) impulse overpressure during a disaster. PMID:28018003

  4. Refuge alternatives relief valve testing and design.

    PubMed

    Lutz, T J; Bissert, P T; Homce, G T; Yonkey, J A

    2016-10-01

    The U.S. National Institute for Occupational Safety and Health (NIOSH) has been researching refuge alternatives (RAs) since 2007. RAs typically have built-in pressure relief valves (PRVs) to prevent the unit from reaching unsafe pressures. The U.S. Mine Safety and Health Administration requires that these valves vent the chamber at a maximum pressure of 1.25 kPa (0.18 psi, 5.0 in. H2O), or as specified by the manufacturer, above mine atmospheric pressure in the RA. To facilitate PRV testing, an instrumented benchtop test fixture was developed using an off-the-shelf centrifugal blower and ductwork. Relief pressures and flow characteristics were measured for three units: (1) a modified polyvinyl chloride check valve, (2) an off-the-shelf brass/cast-iron butterfly check valve and (3) a commercially available valve that was designed specifically for one manufacturer's steel prefabricated RAs and had been adapted for use in one mine operator's built-in-place RA. PRVs used in tent-style RAs were not investigated. The units were tested with different modifications and configurations in order to check compliance with Title 30 Code of Federal Regulations, or 30 CFR, regulations. The commercially available relief valve did not meet the 30 CFR relief pressure specification but may meet the manufacturer's specification. Alternative valve designs were modified to meet the 30 CFR relief pressure specification, but all valve designs will need further design research to examine survivability in the event of a 103 kPa (15.0 psi) impulse overpressure during a disaster.

  5. High-Performance Valve Promises Safe Relief

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Using an improved valve design developed under an SBIR contract with Stennis Space Center, Marotta Scientific's PRV95 provides stability over the entire operational range, from fully closed to fully open. The valve employs a concept known as upstream control for valve positioning, making it more dependable with excellent repeatability and minimal lag time. The PRV95 design is unique in its ability to maintain a seal near the set point of the relief limit. Typically, relief valves seal tightly up to 90 percent set point and then reseat when pressure is reduced to 85 percent of set point. This new technology maintains seal integrity until 98 percent of set point and will reseat at 95 to 97 percent of set point. This allows the operator to protect a system without exceeding its limits.

  6. Liquid rocket valve assemblies

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The design and operating characteristics of valve assemblies used in liquid propellant rocket engines are discussed. The subjects considered are as follows: (1) valve selection parameters, (2) major design aspects, (3) design integration of valve subassemblies, and (4) assembly of components and functional tests. Information is provided on engine, stage, and spacecraft checkout procedures.

  7. 5. DIABLO DAM: DETAIL VIEW OF RELIEF VALVES AT ELEVATION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. DIABLO DAM: DETAIL VIEW OF RELIEF VALVES AT ELEVATION 1044. VALVE IN FOREGROUND IS A BUTTERFLY VALVE SIX FEET IN DIAMETER; VALVE TO THE REAR IS A JOHNSON-TYPE NEEDLE VALVE BOTH VALVES WERE MANUFACTURED BY THE PELTON WATER WHEEL COMPANY, 1989. - Skagit Power Development, Diablo Dam, On Skagit River, 6.9 miles upstream from Newhalem, Newhalem, Whatcom County, WA

  8. 46 CFR 154.1846 - Relief valves: Changing set pressure.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Relief valves: Changing set pressure. 154.1846 Section... Relief valves: Changing set pressure. The master shall: (a) Supervise the changing of the set pressure of relief valves under § 154.802(b); (b) Enter the change of set pressure in the vessel's log; and...

  9. 46 CFR 154.1846 - Relief valves: Changing set pressure.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Relief valves: Changing set pressure. 154.1846 Section... Relief valves: Changing set pressure. The master shall: (a) Supervise the changing of the set pressure of relief valves under § 154.802(b); (b) Enter the change of set pressure in the vessel's log; and...

  10. 46 CFR 154.1846 - Relief valves: Changing set pressure.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Relief valves: Changing set pressure. 154.1846 Section... Relief valves: Changing set pressure. The master shall: (a) Supervise the changing of the set pressure of relief valves under § 154.802(b); (b) Enter the change of set pressure in the vessel's log; and...

  11. 46 CFR 154.1846 - Relief valves: Changing set pressure.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Relief valves: Changing set pressure. 154.1846 Section... Relief valves: Changing set pressure. The master shall: (a) Supervise the changing of the set pressure of relief valves under § 154.802(b); (b) Enter the change of set pressure in the vessel's log; and...

  12. 46 CFR 154.1846 - Relief valves: Changing set pressure.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Relief valves: Changing set pressure. 154.1846 Section... Relief valves: Changing set pressure. The master shall: (a) Supervise the changing of the set pressure of relief valves under § 154.802(b); (b) Enter the change of set pressure in the vessel's log; and...

  13. Liquid blocking check valve

    DOEpatents

    Merrill, John T.

    1984-01-01

    A liquid blocking check valve useful particularly in a pneumatic system utilizing a pressurized liquid fill chamber. The valve includes a floatable ball disposed within a housing defining a chamber. The housing is provided with an inlet aperture disposed in the top of said chamber, and an outlet aperture disposed in the bottom of said chamber in an offset relation to said inlet aperture and in communication with a cutaway side wall section of said housing.

  14. 46 CFR 153.371 - Minimum relief valve setting for refrigerated cargo tanks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... BULK DANGEROUS CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Venting Systems § 153.371 Minimum relief valve setting for refrigerated cargo...

  15. 40 CFR 65.110 - Standards: Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... systems. 65.110 Section 65.110 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Equipment Leaks § 65.110 Standards: Pumps, valves... have been eliminated; that no bubbles are observed at potential leak sites during a leak check using...

  16. 40 CFR 65.110 - Standards: Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... systems. 65.110 Section 65.110 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Equipment Leaks § 65.110 Standards: Pumps, valves... have been eliminated; that no bubbles are observed at potential leak sites during a leak check using...

  17. 40 CFR 65.110 - Standards: Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... systems. 65.110 Section 65.110 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Equipment Leaks § 65.110 Standards: Pumps, valves... have been eliminated; that no bubbles are observed at potential leak sites during a leak check using...

  18. 40 CFR 65.110 - Standards: Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... systems. 65.110 Section 65.110 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Equipment Leaks § 65.110 Standards: Pumps, valves... have been eliminated; that no bubbles are observed at potential leak sites during a leak check using...

  19. 40 CFR 65.110 - Standards: Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... systems. 65.110 Section 65.110 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Equipment Leaks § 65.110 Standards: Pumps, valves... have been eliminated; that no bubbles are observed at potential leak sites during a leak check using...

  20. 46 CFR 64.59 - Spring loaded pressure relief valve.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Spring loaded pressure relief valve. 64.59 Section 64.59 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MARINE PORTABLE TANKS AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.59...

  1. 46 CFR 64.59 - Spring loaded pressure relief valve.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Spring loaded pressure relief valve. 64.59 Section 64.59 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MARINE PORTABLE TANKS AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.59...

  2. 46 CFR 64.59 - Spring loaded pressure relief valve.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Spring loaded pressure relief valve. 64.59 Section 64.59 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MARINE PORTABLE TANKS AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.59...

  3. 46 CFR 64.59 - Spring loaded pressure relief valve.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Spring loaded pressure relief valve. 64.59 Section 64.59 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MARINE PORTABLE TANKS AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.59...

  4. 46 CFR 64.59 - Spring loaded pressure relief valve.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Spring loaded pressure relief valve. 64.59 Section 64.59 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MARINE PORTABLE TANKS AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.59...

  5. Improved Relief Valve Would Be Less Susceptible to Failure

    NASA Technical Reports Server (NTRS)

    Farner, Bruce R.

    2008-01-01

    The balanced-piston relief valve with side vented reaction cavity has been proposed as an improved alternative to a conventional high-pressure, high-flow relief valve. The proposed valve would be less susceptible to failure. A typical conventional high-pressure, high-flow relief valve contains a piston that is exposed to the upstream pressure across the full valve-seat diameter and is held against the valve seat and the upstream pressure by a large spring. In the event of an increase in upstream pressure to a level above the valve set point (the pressure above which the valve opens), the opening force on the piston can be so large that the piston becomes accelerated to a speed high enough that the ensuing hard impact of the piston within the valve housing results in failure of the valve. For a given flow cross section, the proposal would significantly reduce the force, thereby reducing susceptibility to failure. A basic version of the proposed balanced-piston relief valve with side vented reaction cavity is described.

  6. 119. Relief and safety valve of turbine unit no. 1, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    119. Relief and safety valve of turbine unit no. 1, located in the subway below the Generator Room; looking south. The safety valve was manufactured by the Chapman Valve Company of Springfield, Massachusetts. It is identical to the adjacent safety valve for turbine unit no. 2. Photo by Jet Lowe, HAER, 1989. - Puget Sound Power & Light Company, White River Hydroelectric Project, 600 North River Avenue, Dieringer, Pierce County, WA

  7. Liquid-blocking check valve

    DOEpatents

    Merrill, J.T.

    1982-09-27

    A liquid blocking check valve useful particularly in a pneumatic system utilizing a pressurized liquid fill chamber. The valve includes a floatable ball disposed within a housing defining a chamber. The housing is provided with an inlet aperture disposed in the top of said chamber, and an outlet aperture disposed in the bottom of said chamber in an offset relation to said inlet aperture and in communication with a cutaway side wall section of said housing.

  8. 33 CFR 149.105 - What are the requirements for the overflow and relief valves?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Pollution Prevention Equipment § 149.105 What are the requirements for the overflow and relief valves? (a) Each oil and natural gas transfer system (OTS/NGTS) must include a relief valve that, when activated...

  9. 33 CFR 149.105 - What are the requirements for the overflow and relief valves?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Pollution Prevention Equipment § 149.105 What are the requirements for the overflow and relief valves? (a) Each oil and natural gas transfer system (OTS/NGTS) must include a relief valve that, when activated...

  10. 33 CFR 149.105 - What are the requirements for the overflow and relief valves?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Pollution Prevention Equipment § 149.105 What are the requirements for the overflow and relief valves? (a) Each oil and natural gas transfer system (OTS/NGTS) must include a relief valve that, when activated...

  11. 46 CFR 154.519 - Piping relief valves.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS... cargo that is specially approved by the Commandant (CG-ENG). (b) A relief valve on a cargo pump that protects the cargo piping system must discharge into the pump suction....

  12. 46 CFR 154.519 - Piping relief valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS... cargo that is specially approved by the Commandant (CG-522). (b) A relief valve on a cargo pump that protects the cargo piping system must discharge into the pump suction....

  13. 46 CFR 154.519 - Piping relief valves.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS... cargo that is specially approved by the Commandant (CG-ENG). (b) A relief valve on a cargo pump that protects the cargo piping system must discharge into the pump suction....

  14. 46 CFR 154.519 - Piping relief valves.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS... cargo that is specially approved by the Commandant (CG-522). (b) A relief valve on a cargo pump that protects the cargo piping system must discharge into the pump suction....

  15. 46 CFR 98.25-60 - Safety relief valves.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Safety relief valves. 98.25-60 Section 98.25-60 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk...

  16. 46 CFR 98.25-60 - Safety relief valves.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Safety relief valves. 98.25-60 Section 98.25-60 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk...

  17. 46 CFR 98.25-60 - Safety relief valves.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Safety relief valves. 98.25-60 Section 98.25-60 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk...

  18. 46 CFR 98.25-60 - Safety relief valves.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Safety relief valves. 98.25-60 Section 98.25-60 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk...

  19. 46 CFR 98.25-60 - Safety relief valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Safety relief valves. 98.25-60 Section 98.25-60 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk...

  20. 22. TURBINE PIT AREA GORGE POWERHOUSE SHOWING RELIEF VALVE FOR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    22. TURBINE PIT AREA GORGE POWERHOUSE SHOWING RELIEF VALVE FOR UNIT 23 IN FOREGROUND AND GOVERNOR OIL TANKS AND PUMPS IN THE LEFT REAR, 1989. - Skagit Power Development, Gorge Powerhouse, On Skagit River, 0.4 mile upstream from Newhalem, Newhalem, Whatcom County, WA

  1. MERADCOM/OSU Assessment and Rating of the Contaminant Sensitivity of Relief Valves.

    DTIC Science & Technology

    1980-10-01

    valve . Contaminant wear on the poppet also causes a decrease in the reseating pressure of a relief valve . This...teristics of the valve . As the physical shape of the poppet or piston is changed due to wear , the flow forces acting upon them are also changed. This results...Contaminant Wear Erosive Wear Abrasive Wear Contaminant Lock Direct-Acting Relief Valves Pilot-Operated Relief Valves Contaminant Tolerance Profile

  2. 46 CFR 64.91 - Relief valve for the cargo pump discharge.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Relief valve for the cargo pump discharge. 64.91 Section... PORTABLE TANKS AND CARGO HANDLING SYSTEMS Cargo Handling System § 64.91 Relief valve for the cargo pump discharge. The cargo pump discharge must have a relief valve that is— (a) Fitted between the cargo...

  3. 46 CFR 64.91 - Relief valve for the cargo pump discharge.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Relief valve for the cargo pump discharge. 64.91 Section... PORTABLE TANKS AND CARGO HANDLING SYSTEMS Cargo Handling System § 64.91 Relief valve for the cargo pump discharge. The cargo pump discharge must have a relief valve that is— (a) Fitted between the cargo...

  4. 46 CFR 64.91 - Relief valve for the cargo pump discharge.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Relief valve for the cargo pump discharge. 64.91 Section... PORTABLE TANKS AND CARGO HANDLING SYSTEMS Cargo Handling System § 64.91 Relief valve for the cargo pump discharge. The cargo pump discharge must have a relief valve that is— (a) Fitted between the cargo...

  5. 46 CFR 64.91 - Relief valve for the cargo pump discharge.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Relief valve for the cargo pump discharge. 64.91 Section... PORTABLE TANKS AND CARGO HANDLING SYSTEMS Cargo Handling System § 64.91 Relief valve for the cargo pump discharge. The cargo pump discharge must have a relief valve that is— (a) Fitted between the cargo...

  6. 46 CFR 64.91 - Relief valve for the cargo pump discharge.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Relief valve for the cargo pump discharge. 64.91 Section... PORTABLE TANKS AND CARGO HANDLING SYSTEMS Cargo Handling System § 64.91 Relief valve for the cargo pump discharge. The cargo pump discharge must have a relief valve that is— (a) Fitted between the cargo...

  7. 49 CFR 179.220-24 - Tests of pressure relief valves.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Tests of pressure relief valves. 179.220-24... CARS Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179.220-24 Tests of pressure relief valves. Each safety relief valve must be tested by air or gas for compliance with §...

  8. 46 CFR 38.25-10 - Safety relief valves-TB/ALL.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Safety relief valves-TB/ALL. 38.25-10 Section 38.25-10... and Inspections § 38.25-10 Safety relief valves—TB/ALL. (a) The cargo tank safety relief valves shall be inspected at least once in every 2 years. (b) The safety relief valve discs must be lifted from...

  9. 49 CFR 179.200-23 - Tests of pressure relief valves.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Tests of pressure relief valves. 179.200-23... CARS Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179.200-23 Tests of pressure relief valves. (a) Each valve shall be tested by air or gas for compliance with § 179.15...

  10. 49 CFR 179.400-21 - Test of pressure relief valves.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Test of pressure relief valves. 179.400-21 Section 179.400-21 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND... 107A) § 179.400-21 Test of pressure relief valves. Each valve must be tested with air or gas...

  11. 46 CFR 32.20-5 - Pressure vacuum relief valves-TB/ALL.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false Pressure vacuum relief valves-TB/ALL. 32.20-5 Section 32..., AND HULL REQUIREMENTS Equipment Installations § 32.20-5 Pressure vacuum relief valves—TB/ALL. The pressure vacuum relief valve shall be of a type and size approved by the Commandant for the...

  12. 46 CFR 32.20-5 - Pressure vacuum relief valves-TB/ALL.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false Pressure vacuum relief valves-TB/ALL. 32.20-5 Section 32..., AND HULL REQUIREMENTS Equipment Installations § 32.20-5 Pressure vacuum relief valves—TB/ALL. The pressure vacuum relief valve shall be of a type and size approved by the Commandant for the...

  13. 46 CFR 30.10-55 - Pressure vacuum relief valve-TB/ALL.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false Pressure vacuum relief valve-TB/ALL. 30.10-55 Section 30... Definitions § 30.10-55 Pressure vacuum relief valve—TB/ALL. The term pressure vacuum relief valve means any... pressure or vacuum in enclosed places....

  14. 46 CFR 30.10-55 - Pressure vacuum relief valve-TB/ALL.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false Pressure vacuum relief valve-TB/ALL. 30.10-55 Section 30... Definitions § 30.10-55 Pressure vacuum relief valve—TB/ALL. The term pressure vacuum relief valve means any... pressure or vacuum in enclosed places....

  15. 46 CFR 32.20-5 - Pressure vacuum relief valves-TB/ALL.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 1 2012-10-01 2012-10-01 false Pressure vacuum relief valves-TB/ALL. 32.20-5 Section 32..., AND HULL REQUIREMENTS Equipment Installations § 32.20-5 Pressure vacuum relief valves—TB/ALL. The pressure vacuum relief valve shall be of a type and size approved by the Commandant for the...

  16. 46 CFR 32.20-5 - Pressure vacuum relief valves-TB/ALL.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Pressure vacuum relief valves-TB/ALL. 32.20-5 Section 32..., AND HULL REQUIREMENTS Equipment Installations § 32.20-5 Pressure vacuum relief valves—TB/ALL. The pressure vacuum relief valve shall be of a type and size approved by the Commandant for the...

  17. 46 CFR 30.10-55 - Pressure vacuum relief valve-TB/ALL.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 1 2012-10-01 2012-10-01 false Pressure vacuum relief valve-TB/ALL. 30.10-55 Section 30... Definitions § 30.10-55 Pressure vacuum relief valve—TB/ALL. The term pressure vacuum relief valve means any... pressure or vacuum in enclosed places....

  18. 46 CFR 30.10-55 - Pressure vacuum relief valve-TB/ALL.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Pressure vacuum relief valve-TB/ALL. 30.10-55 Section 30... Definitions § 30.10-55 Pressure vacuum relief valve—TB/ALL. The term pressure vacuum relief valve means any... pressure or vacuum in enclosed places....

  19. 46 CFR 32.20-5 - Pressure vacuum relief valves-TB/ALL.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false Pressure vacuum relief valves-TB/ALL. 32.20-5 Section 32..., AND HULL REQUIREMENTS Equipment Installations § 32.20-5 Pressure vacuum relief valves—TB/ALL. The pressure vacuum relief valve shall be of a type and size approved by the Commandant for the...

  20. 46 CFR 30.10-55 - Pressure vacuum relief valve-TB/ALL.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false Pressure vacuum relief valve-TB/ALL. 30.10-55 Section 30... Definitions § 30.10-55 Pressure vacuum relief valve—TB/ALL. The term pressure vacuum relief valve means any... pressure or vacuum in enclosed places....

  1. 46 CFR 38.25-10 - Safety relief valves-TB/ALL.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false Safety relief valves-TB/ALL. 38.25-10 Section 38.25-10 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS LIQUEFIED FLAMMABLE GASES Periodic Tests and Inspections § 38.25-10 Safety relief valves—TB/ALL. (a) The cargo tank safety relief valves...

  2. 46 CFR 54.15-10 - Safety and relief valves (modifies UG-126).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... PRESSURE VESSELS Pressure-Relief Devices § 54.15-10 Safety and relief valves (modifies UG-126). (a) All safety and relief valves for use on pressure vessels or piping systems shall be designed to meet the... which does not exceed the “maximum allowable working pressure” of the pressure vessel or piping system...

  3. 46 CFR 54.15-10 - Safety and relief valves (modifies UG-126).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... PRESSURE VESSELS Pressure-Relief Devices § 54.15-10 Safety and relief valves (modifies UG-126). (a) All safety and relief valves for use on pressure vessels or piping systems shall be designed to meet the... which does not exceed the “maximum allowable working pressure” of the pressure vessel or piping system...

  4. 46 CFR 54.15-10 - Safety and relief valves (modifies UG-126).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Safety and relief valves (modifies UG-126). 54.15-10 Section 54.15-10 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PRESSURE VESSELS Pressure-Relief Devices § 54.15-10 Safety and relief valves (modifies UG-126). (a) All...

  5. 46 CFR 54.15-10 - Safety and relief valves (modifies UG-126).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Safety and relief valves (modifies UG-126). 54.15-10 Section 54.15-10 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PRESSURE VESSELS Pressure-Relief Devices § 54.15-10 Safety and relief valves (modifies UG-126). (a) All...

  6. 46 CFR 54.15-10 - Safety and relief valves (modifies UG-126).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Safety and relief valves (modifies UG-126). 54.15-10 Section 54.15-10 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PRESSURE VESSELS Pressure-Relief Devices § 54.15-10 Safety and relief valves (modifies UG-126). (a) All...

  7. Influence of pressurizer relief valves on success of ``feed and bleed`` procedure

    SciTech Connect

    Petelin, S.; Mavko, B.; Gortnar, O.

    1994-12-31

    The RELAP5/MOD3.1 analysis of the accident with total loss of secondary heat sink was performed for Krsko nuclear power plant which is a two loop Westinghouse PWR power plant of 1,876 MW thermal power. In the study of ``feed and bleed`` accident managing the particular attention was given to the emergency operating procedures foreseen operator actions. This paper deals with the modeling of saturated liquid and two-phase mixture critical discharge through the pressurizer power operated relief valves and aims to evaluate its influence on the simulation of other thermal-hydraulic processes in the reactor coolant system. The time evolution of simulated accident and the determination of the longest allowed operator response time for the successful accident managing were shown to be much dependent on the prediction of critical flow through the pressurizer relief valves.

  8. Liquid crystal light valve structures

    NASA Technical Reports Server (NTRS)

    Koda, N. J. (Inventor)

    1985-01-01

    An improved photosensor film and liquid crystal light valves embodying said film is provided. The photosensor film and liquid crystal light valve is characterized by a significant lower image retention time while maintaining acceptable photosensitivity. The photosensor film is produced by sputter depositing CdS onto an ITO substrate in an atmosphere of argon/H2S gas while maintaining the substrate at a temperature in the range of about 130 C to about 200 C and while introducing nitrogen gas into the system to the extent of not more than about 1% of plasma mixture. Following sputter deposition of the CdS, the film is annealed in an inert gas at temperatures ranging from about 300 C to about 425 C.

  9. 49 CFR 179.100-19 - Tests of safety relief valves.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... CARS Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120) § 179.100-19 Tests of safety relief valves. (a) Each valve shall be tested by air or gas for compliance with §...

  10. 49 CFR 179.100-19 - Tests of safety relief valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... CARS Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120) § 179.100-19 Tests of safety relief valves. (a) Each valve shall be tested by air or gas for compliance with §...

  11. 49 CFR 179.100-19 - Tests of safety relief valves.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... CARS Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120) § 179.100-19 Tests of safety relief valves. (a) Each valve shall be tested by air or gas for compliance with §...

  12. 49 CFR 179.100-19 - Tests of safety relief valves.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... CARS Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120) § 179.100-19 Tests of safety relief valves. (a) Each valve shall be tested by air or gas for compliance with §...

  13. Study on hydraulic direct-acting relief valve

    NASA Astrophysics Data System (ADS)

    Syrkin, V. V.; Balakin, P. D.; Treyer, V. A.

    2017-06-01

    Valves with elastic shut-off-and-regulating elements are increasingly applied in hydraulic systems, working in conditions of excessive vibrations. The objective of this study is to determine the dynamic characteristics of regulators with shut-off-and- regulating elements. The method of phase trajectories establishes the controller’s parameters and modes, which provide its work stability. The authors receive dynamic characteristics providing the absence of self-oscillations at the expense of additional damping of the shut-off- and-regulating element. They make a test sample of the pressure regulator with an elastic shut-off-and-regulating element. The article defines the characteristics curve of the pressure regulator (direct operated pressure relief valve) from the initial conditions. The obtained results can be used, when designing hydraulic technological machines. Keywords - oscillation damping, an elastic shut-off-and regulating element.

  14. Grazing bifurcations and chatter in a pressure relief valve model

    NASA Astrophysics Data System (ADS)

    Hős, Csaba; Champneys, Alan R.

    2012-11-01

    This paper considers a simple mechanical model of a pressure relief valve. For a wide region of parameter values, the valve undergoes self-oscillations that involve impact with the valve seat. These oscillations are born in a Hopf bifurcation that can be either super- or sub-critical. In either case, the onset of more complex oscillations is caused by the occurrence of grazing bifurcations, where the limit cycle first becomes tangent to the discontinuity surface that represents valve contact. The complex dynamics that ensues from such points as the flow speed is decreased has previously been reported via brute-force bifurcation diagrams. Here, the nature of the transitions is further elucidated via the numerical continuation of impacting orbits. In addition, two-parameter continuation results for Hopf and grazing bifurcations as well as the continuation of period-doubling bifurcations of impacting orbits are presented. For yet lower flow speeds, new results reveal chattering motion, that is where there are many impacts in a finite time interval. The geometry of the chattering region is analysed via the computation of several pre-images of the grazing set. It is shown how these pre-images organise the dynamics, in particular by separating initial conditions that lead to complete chatter (an accumulation of impacts) from those which do not.

  15. 8-inch Reflange Inlet and Two 6-inch 600# Flange Outlets Relief Valve Description and Specifications

    NASA Technical Reports Server (NTRS)

    2005-01-01

    In the past, an Anderson Greenwood (AG) pilot operated relief valve was used to protect the E-1 rocket engine test facility. It was found that the AG valve is destroyed and discharges internal parts at a great velocity on opening. This is a major safety and cost issue. The solution is a relief valve to match present Anderson Greenwood pilot valve A 8z B dimensions. The valve is to use a precise buckling pin obeying Euler s Law to act as the pressure sensor and actuator. The valve must not self destruct on opening.

  16. 46 CFR 36.10-1 - Cargo pump relief valves-TB/ALL.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false Cargo pump relief valves-TB/ALL. 36.10-1 Section 36.10-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS ELEVATED TEMPERATURE CARGOES Piping, Valves, Fittings, and Accessory Equipment § 36.10-1 Cargo pump relief valves—TB/ALL. (a) Cargo...

  17. 46 CFR 36.10-1 - Cargo pump relief valves-TB/ALL.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false Cargo pump relief valves-TB/ALL. 36.10-1 Section 36.10-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS ELEVATED TEMPERATURE CARGOES Piping, Valves, Fittings, and Accessory Equipment § 36.10-1 Cargo pump relief valves—TB/ALL. (a) Cargo...

  18. 46 CFR 36.10-1 - Cargo pump relief valves-TB/ALL.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 1 2012-10-01 2012-10-01 false Cargo pump relief valves-TB/ALL. 36.10-1 Section 36.10-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS ELEVATED TEMPERATURE CARGOES Piping, Valves, Fittings, and Accessory Equipment § 36.10-1 Cargo pump relief valves—TB/ALL. (a) Cargo...

  19. 46 CFR 36.10-1 - Cargo pump relief valves-TB/ALL.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false Cargo pump relief valves-TB/ALL. 36.10-1 Section 36.10-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS ELEVATED TEMPERATURE CARGOES Piping, Valves, Fittings, and Accessory Equipment § 36.10-1 Cargo pump relief valves—TB/ALL. (a) Cargo...

  20. 46 CFR 36.10-1 - Cargo pump relief valves-TB/ALL.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Cargo pump relief valves-TB/ALL. 36.10-1 Section 36.10-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS ELEVATED TEMPERATURE CARGOES Piping, Valves, Fittings, and Accessory Equipment § 36.10-1 Cargo pump relief valves—TB/ALL. (a) Cargo...

  1. 46 CFR 38.10-15 - Safety relief valves-TB/ALL.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Safety relief valves-TB/ALL. 38.10-15 Section 38.10-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS LIQUEFIED FLAMMABLE GASES Piping, Valves, Fittings, and Accessory Equipment § 38.10-15 Safety relief valves—TB/ALL. (a) Each tank shall be...

  2. 77 FR 59408 - Finding of Equivalence; Alternate Pressure Relief Valve Settings on Certain Vessels Carrying...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-27

    ...] Finding of Equivalence; Alternate Pressure Relief Valve Settings on Certain Vessels Carrying Liquefied... announces the availability of CG-ENG Policy Letter 04-12, ``Alternative Pressure Relief Valve Settings on... Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (BPVC) Section VIII with respect...

  3. 49 CFR 179.220-24 - Tests of pressure relief valves.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... CARS Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179.220-24 Tests of pressure relief valves. Each safety relief valve must be tested by air or gas for compliance with §...

  4. 49 CFR 179.220-24 - Tests of pressure relief valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... CARS Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179.220-24 Tests of pressure relief valves. Each safety relief valve must be tested by air or gas for compliance with §...

  5. 49 CFR 179.220-24 - Tests of pressure relief valves.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... CARS Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179.220-24 Tests of pressure relief valves. Each safety relief valve must be tested by air or gas for compliance with §...

  6. 46 CFR 153.370 - Minimum relief valve setting for ambient temperature cargo tanks.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Minimum relief valve setting for ambient temperature... temperature cargo tanks. The relief valve setting for a containment system that carries a cargo at ambient temperature must at least equal the cargo's vapor pressure at 46 °C (approx. 115 °F). ...

  7. 46 CFR 153.370 - Minimum relief valve setting for ambient temperature cargo tanks.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Minimum relief valve setting for ambient temperature... temperature cargo tanks. The relief valve setting for a containment system that carries a cargo at ambient temperature must at least equal the cargo's vapor pressure at 46 °C (approx. 115 °F). ...

  8. 46 CFR 153.370 - Minimum relief valve setting for ambient temperature cargo tanks.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Minimum relief valve setting for ambient temperature... temperature cargo tanks. The relief valve setting for a containment system that carries a cargo at ambient temperature must at least equal the cargo's vapor pressure at 46 °C (approx. 115 °F). ...

  9. 46 CFR 153.370 - Minimum relief valve setting for ambient temperature cargo tanks.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Minimum relief valve setting for ambient temperature... temperature cargo tanks. The relief valve setting for a containment system that carries a cargo at ambient temperature must at least equal the cargo's vapor pressure at 46 °C (approx. 115 °F). ...

  10. 46 CFR 153.370 - Minimum relief valve setting for ambient temperature cargo tanks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Minimum relief valve setting for ambient temperature... temperature cargo tanks. The relief valve setting for a containment system that carries a cargo at ambient temperature must at least equal the cargo's vapor pressure at 46 °C (approx. 115 °F). ...

  11. 46 CFR 53.05-2 - Relief valve requirements for hot water boilers (modifies HG-400.2).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Relief valve requirements for hot water boilers... (CONTINUED) MARINE ENGINEERING HEATING BOILERS Pressure Relieving Devices (Article 4) § 53.05-2 Relief valve requirements for hot water boilers (modifies HG-400.2). (a) The relief valve requirements for hot water...

  12. 46 CFR 53.05-2 - Relief valve requirements for hot water boilers (modifies HG-400.2).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Relief valve requirements for hot water boilers... (CONTINUED) MARINE ENGINEERING HEATING BOILERS Pressure Relieving Devices (Article 4) § 53.05-2 Relief valve requirements for hot water boilers (modifies HG-400.2). (a) The relief valve requirements for hot water...

  13. 46 CFR 53.05-2 - Relief valve requirements for hot water boilers (modifies HG-400.2).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Relief valve requirements for hot water boilers... (CONTINUED) MARINE ENGINEERING HEATING BOILERS Pressure Relieving Devices (Article 4) § 53.05-2 Relief valve requirements for hot water boilers (modifies HG-400.2). (a) The relief valve requirements for hot water...

  14. 46 CFR 53.05-2 - Relief valve requirements for hot water boilers (modifies HG-400.2).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Relief valve requirements for hot water boilers... (CONTINUED) MARINE ENGINEERING HEATING BOILERS Pressure Relieving Devices (Article 4) § 53.05-2 Relief valve requirements for hot water boilers (modifies HG-400.2). (a) The relief valve requirements for hot water...

  15. 46 CFR 53.05-2 - Relief valve requirements for hot water boilers (modifies HG-400.2).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Relief valve requirements for hot water boilers... (CONTINUED) MARINE ENGINEERING HEATING BOILERS Pressure Relieving Devices (Article 4) § 53.05-2 Relief valve requirements for hot water boilers (modifies HG-400.2). (a) The relief valve requirements for hot water...

  16. Development of large-capacity main steam isolation valves and safety relief valves for next-generation BWR plant

    SciTech Connect

    Mitsugu Nishimura; Shin-ichi Furukawa; Gen Itoh; Kikuo Takeshima

    2002-07-01

    A study was made of high capacity main steam isolation valves (MSIV) and safety relief valves (SRV) for the main steam line of a boiling water reactor (BWR). The next-generation BWR plants, which are planned to have higher thermal power, have raised concerns relating to the main steam line of an increase in maintenance work to SRVs and erosion of the MSIV valve seat due to the increased main steam flow velocity. In this research project, the capacity of the MSIV and SRV was increased and the valve configuration was changed in an attempt to solve these problems. (authors)

  17. 46 CFR 38.10-15 - Safety relief valves-TB/ALL.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false Safety relief valves-TB/ALL. 38.10-15 Section 38.10-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS LIQUEFIED FLAMMABLE GASES Piping, Valves... excessive external pressure. (f) Void spaces between the primary and secondary barriers of...

  18. 46 CFR 38.10-15 - Safety relief valves-TB/ALL.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 1 2012-10-01 2012-10-01 false Safety relief valves-TB/ALL. 38.10-15 Section 38.10-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS LIQUEFIED FLAMMABLE GASES Piping, Valves... excessive external pressure. (f) Void spaces between the primary and secondary barriers of...

  19. 46 CFR 56.50-25 - Safety and relief valve escape piping.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Safety and relief valve escape piping. 56.50-25 Section 56.50-25 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PIPING... valve escape piping. (a) Escape piping from unfired steam generator, boiler, and superheater safety...

  20. 49 CFR 179.200-23 - Tests of pressure relief valves.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... CARS Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179.200-23 Tests of pressure relief valves. (a) Each valve shall be tested by air or gas for compliance with § 179.15...

  1. 49 CFR 179.200-23 - Tests of pressure relief valves.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... CARS Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179.200-23 Tests of pressure relief valves. (a) Each valve shall be tested by air or gas for compliance with § 179.15...

  2. 49 CFR 179.200-23 - Tests of pressure relief valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... CARS Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179.200-23 Tests of pressure relief valves. (a) Each valve shall be tested by air or gas for compliance with § 179.15...

  3. 46 CFR 154.517 - Piping: Liquid pressure relief.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Piping: Liquid pressure relief. 154.517 Section 154.517... and Process Piping Systems § 154.517 Piping: Liquid pressure relief. The cargo loading and discharge... remove liquid cargo....

  4. ANALYSIS OF SAFETY RELIEF VALVE PROOF TEST DATA TO OPTIMIZE LIFECYCLE MAINTENANCE COSTS

    SciTech Connect

    Gross, Robert; Harris, Stephen

    2007-08-01

    Proof test results were analyzed and compared with a proposed life cycle curve or hazard function and the limit of useful life. Relief valve proof testing procedures, statistical modeling, data collection processes, and time-in-service trends are presented. The resulting analysis of test data allows for the estimation of the PFD. Extended maintenance intervals to the limit of useful life as well as methodologies and practices for improving relief valve performance and reliability are discussed. A generic cost-benefit analysis and an expected life cycle cost reduction concludes that $90 million maintenance dollars might be avoided for a population of 3000 valves over 20 years.

  5. 46 CFR 52.01-120 - Safety valves and safety relief valves (modifies PG-67 through PG-73).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (CONTINUED) MARINE ENGINEERING POWER BOILERS General Requirements § 52.01-120 Safety valves and safety relief... lifting bars. When used for these parts, the elongation must be at least 5 percent in 51mm (2 inch) gage... noted in paragraph (d)(2) of this section. (2) (Modifies PG-73.) The lifting device required by PG-73.1...

  6. 46 CFR 52.01-120 - Safety valves and safety relief valves (modifies PG-67 through PG-73).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... (CONTINUED) MARINE ENGINEERING POWER BOILERS General Requirements § 52.01-120 Safety valves and safety relief... lifting bars. When used for these parts, the elongation must be at least 5 percent in 51mm (2 inch) gage... noted in paragraph (d)(2) of this section. (2) (Modifies PG-73.) The lifting device required by PG-73.1...

  7. 46 CFR 52.01-120 - Safety valves and safety relief valves (modifies PG-67 through PG-73).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (CONTINUED) MARINE ENGINEERING POWER BOILERS General Requirements § 52.01-120 Safety valves and safety relief... lifting bars. When used for these parts, the elongation must be at least 5 percent in 51mm (2 inch) gage... noted in paragraph (d)(2) of this section. (2) (Modifies PG-73.) The lifting device required by PG-73.1...

  8. 46 CFR 154.517 - Piping: Liquid pressure relief.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Piping: Liquid pressure relief. 154.517 Section 154.517... and Process Piping Systems § 154.517 Piping: Liquid pressure relief. The cargo loading and discharge crossover headers, cargo hoses, and cargo loading arms must have means to relieve cargo pressure and...

  9. 46 CFR 154.517 - Piping: Liquid pressure relief.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Piping: Liquid pressure relief. 154.517 Section 154.517... and Process Piping Systems § 154.517 Piping: Liquid pressure relief. The cargo loading and discharge crossover headers, cargo hoses, and cargo loading arms must have means to relieve cargo pressure and...

  10. 46 CFR 154.517 - Piping: Liquid pressure relief.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Piping: Liquid pressure relief. 154.517 Section 154.517... and Process Piping Systems § 154.517 Piping: Liquid pressure relief. The cargo loading and discharge crossover headers, cargo hoses, and cargo loading arms must have means to relieve cargo pressure and...

  11. 46 CFR 154.517 - Piping: Liquid pressure relief.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Piping: Liquid pressure relief. 154.517 Section 154.517... and Process Piping Systems § 154.517 Piping: Liquid pressure relief. The cargo loading and discharge crossover headers, cargo hoses, and cargo loading arms must have means to relieve cargo pressure and...

  12. Navier-Stokes Flow Field Analysis of Compressible Flow in a Pressure Relief Valve

    NASA Technical Reports Server (NTRS)

    Vu, Bruce T.; Wang, Ten-See; Shih, Ming-Hsin; Soni, Bharat K.

    1993-01-01

    The present study was motivated to analyze the complex flow field involving gaseous oxygen (GOX) flow in a relief valve (RV). The 9391 RV, pictured in Figure 1, was combined with the pilot valve to regulate the actuation pressure of the main valve system. During a high-pressure flow test at Marshall Space Flight Center (MSFC) the valve system developed a resonance chatter, which destroyed most of the valve body. Figures 2-4 show the valve body before and after accident. It was understood that the subject RV has never been operated at 5500 psia. In order to fully understand the flow behavior in the RV, a computational fluid dynamics (CFD) analysis is carried out to investigate the side load across the piston sleeve and the erosion patterns resulting from flow distribution around piston/nozzle interface.

  13. Analysis of HFIR pressurizer pump overspeed transients and relief valve performance

    SciTech Connect

    Sozer, M.C.

    1992-09-11

    The pressurizer pump overspeed transients at the High Flux Isotope Reactor (HFIR) fall in the category of {open_quotes}increase in coolant inventory transients.{close_quotes} They are among the accident transients to be performed for Chapter 15 of the HFIR safety analysis report (SAR). The pressurizer pump speed starting to increase inadvertently to reach its maximum speed of 3,560 rpm while the reactor operates under normal conditions is the cause of this transient. Increased primary coolant system pressure due to increased pressurizer pump flow into the primary coolant head tank challenges the relief valves to open. If the relief valves do not open, increased primary coolant system pressure will challenge the integrity of the high pressure boundary. Two sets of analyses were performed to analyze the pressurizer pump overspeed transients. The purpose of the first analysis is to estimate how long it will take for the relief valves to open under different conditions and whether or not they will chatter or flutter for a considerable amount of time. The analysis estimates relief valve performance and stability using four different relief valve subsystem models. The relief valve subsystem models are not attached to the primary coolant system model. Vigorous pressure oscillations were produced in all of the computations performed as part of the first analysis. The second analysis includes new simulations of the pressurizer pump overspeed transients that were previously simulated using the RELAP5 thermal-hydraulic computer code. The HFIRSYS, High Flux Isotope Reactor System Transient Analysis computer code, was utilized for these simulations providing referable results for comparisons. The increased pressurizer pump flow due to runaway pressurizer pump speed pressurizes the primary coolant system. The assumptions were made in such a way to form constraining conditions at initiation of and during the transients to generate as high an overpressure situation as possible.

  14. DETAIL OF THE LIQUID HYDROGEN AND LIQUID OXYGEN VENT VALVES, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL OF THE LIQUID HYDROGEN AND LIQUID OXYGEN VENT VALVES, SIXTH LEVEL OF THE EXTERNAL TANK CHECK-OUT CELLS, HB-2, FACING NORTHEAST - Cape Canaveral Air Force Station, Launch Complex 39, Vehicle Assembly Building, VAB Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  15. Examples, clarifications, and guidance on preparing requests for relief from pump and valve inservice testing requirements

    SciTech Connect

    Ransom, C.B.; Hartley, R.S.

    1996-02-01

    In this report, the Idaho National Engineering Laboratory reviewers discuss related to requests for relief from the American Society of Mechanical Engineers code requirements for inservice testing (IST) of safety-related pumps and valves at commercial nuclear power plants. This report compiles information and examples that may be useful to licensees in developing relief requests submitted to US Nuclear Regulatory Commission (NRC) for their consideration and provides insights and recommendations on related IST issues. The report also gives specific guidance on relief requests acceptable and not acceptable to the NRC and advises licensees in the use of this information for application at their facilities.

  16. 46 CFR 58.16-15 - Valves and safety relief devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Valves and safety relief devices. 58.16-15 Section 58.16-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS Liquefied Petroleum Gases for Cooking and Heating § 58.16-15...

  17. 46 CFR 58.16-15 - Valves and safety relief devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Valves and safety relief devices. 58.16-15 Section 58.16-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS Liquefied Petroleum Gases for Cooking and Heating § 58.16-15...

  18. 46 CFR 58.16-15 - Valves and safety relief devices.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Valves and safety relief devices. 58.16-15 Section 58.16-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS Liquefied Petroleum Gases for Cooking and Heating § 58.16-15...

  19. 46 CFR 58.16-15 - Valves and safety relief devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Valves and safety relief devices. 58.16-15 Section 58.16-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS Liquefied Petroleum Gases for Cooking and Heating § 58.16-15...

  20. 46 CFR 58.16-15 - Valves and safety relief devices.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Valves and safety relief devices. 58.16-15 Section 58.16-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MAIN AND AUXILIARY MACHINERY AND RELATED SYSTEMS Liquefied Petroleum Gases for Cooking and Heating § 58.16-15...

  1. 33 CFR 149.105 - What are the requirements for the overflow and relief valves?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false What are the requirements for the overflow and relief valves? 149.105 Section 149.105 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DEEPWATER PORTS DEEPWATER PORTS: DESIGN, CONSTRUCTION, AND...

  2. 49 CFR 179.400-21 - Test of pressure relief valves.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Test of pressure relief valves. 179.400-21 Section 179.400-21 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS SPECIFICATIONS FOR TANK CARS Specification for Cryogenic...

  3. 49 CFR 179.200-23 - Tests of pressure relief valves.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Tests of pressure relief valves. 179.200-23 Section 179.200-23 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS SPECIFICATIONS FOR TANK CARS Specifications for Non-Pressur...

  4. 49 CFR 179.220-24 - Tests of pressure relief valves.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Tests of pressure relief valves. 179.220-24 Section 179.220-24 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS SPECIFICATIONS FOR TANK CARS Specifications for Non-Pressur...

  5. 49 CFR 179.100-19 - Tests of safety relief valves.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Tests of safety relief valves. 179.100-19 Section 179.100-19 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS...

  6. Recent performance experience with US light water reactor self-actuating safety and relief valves

    SciTech Connect

    Hammer, C.G.

    1996-12-01

    Over the past several years, there have been a number of operating reactor events involving performance of primary and secondary safety and relief valves in U.S. Light Water Reactors. There are several different types of safety and relief valves installed for overpressure protection of various safety systems throughout a typical nuclear power plant. The following discussion is limited to those valves in the reactor coolant systems (RCS) and main steam systems of pressurized water reactors (PWR) and in the RCS of boiling water reactors (BWR), all of which are self-actuating having a setpoint controlled by a spring-loaded disk acting against system fluid pressure. The following discussion relates some of the significant recent experience involving operating reactor events or various testing data. Some of the more unusual and interesting operating events or test data involving some of these designs are included, in addition to some involving a number of similar events and those which have generic applicability.

  7. The Liquid Metal Plasma Valve Closing Switch

    DTIC Science & Technology

    1976-11-01

    Specifications Closing HVDC LMPV Switch Converter LMPV Circuit Parameter Parameters Rating Breaker Rating Peak Voltage 50-200 kV 150 kV nominal 30...last column of the table outliner the ratings of the LMPV used in an existing circuit breaker system. The capability of the LMPV to operate at high...1976. W. 0. Eckhardt and G. A. Hofmann, ’’Ohmic Heading DC Circuit Breakers with Liquid-Metal Plasma Valves, 11 Proceedings of the Ninth Symposium on

  8. Note: A low leakage liquid seal for micromachined gas valves

    NASA Astrophysics Data System (ADS)

    Evans, Allan T.; Gianchandani, Yogesh B.

    2010-06-01

    We report a method for addressing gas leakage in micromachined valves. The valves used for evaluating the proposed concept utilize a silicon valve seat that is bonded to a glass substrate and actuated by a piezoelectric stack, all of which are assembled within a ceramic package. The sealing method uses the capillary forces of a liquid sealant on the valve seat to reduce gas leakage below measurable limits. The gas leak rates are compared in valves with and without the seal enhancement. For example, a valve closes against 13.5 kPa with 10 V actuation, compared to 40 V required without the enhancement. Leakage is also evaluated for liquid flow.

  9. Emergency relief venting of the infrared telescope liquid helium dewar

    NASA Technical Reports Server (NTRS)

    Urban, E. W.

    1980-01-01

    An analysis is made of the emergency relief venting of the liquid helium dewar of the Spacelab 2 infrared telescope experiment in the event of a massive failure of the dewar guard vacuum. Such a failure, resulting from a major accident, could cause rapid heating and pressurization of the liquid helium in the dewar and lead to relief venting through the emergency relief system. The heat input from an accident is estimated for various fluid conditions in the dewar and the relief process as it takes place through one or both of the emergency relief paths is considered. It is shown that under all reasonable circumstances the dewar will safely relieve itself, and the pressure will not exceed 85 percent of the proof pressure or 63 percent of the burst pressure.

  10. 49 CFR 178.337-9 - Pressure relief devices, piping, valves, hoses, and fittings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... furnishing refrigeration may be mounted on the motor vehicle. (2) Where any liquid susceptible to freezing... primary valve body parts and fittings used in liquid filling or vapor equalization. Stainless steel may be... and outlet must be marked “liquid” or “vapor” to designate whether it communicates with liquid or...

  11. An experimental study on the stability of a direct spring loaded poppet relief valve

    NASA Astrophysics Data System (ADS)

    Bazsó, C.; Hős, C. J.

    2013-10-01

    This paper presents detailed experimental results on the static and dynamic behaviour of a hydraulic pressure relief valve with poppet valve body, with a special emphasis on the parameters influencing the valve instability. The first part of the paper presents the static measurements; sonic velocity in the hydraulic hose, discharge coefficient and fluid flow forces. The results are compared to the data found in the literature and a reasonable agreement was found. The second part presents dynamic measurements of valve chatter. While varying the feed flow rate, pressure and displacement time histories were recorded for a wide range of set pressure. It is shown that the spectra of both signals have similar frequency content, moreover, the frequency of chatter is fairly constant for a wide parameter range, both in terms of flow rate and set pressure. The regimes of qualitatively different motion forms (stable operation, free, impacting and chaotic oscillations) are shown in the flow rate-set pressure parameter plane.

  12. Large volume liquid helium relief device verifacation apparatus for the alpha magnetic spectrometer

    NASA Astrophysics Data System (ADS)

    Klimas, Richard John; McIntyre, P.; Colvin, John; Zeigler, John; Van Sciver, Steven; Ting, Samual

    2012-06-01

    Here we present details of an experiment for verifying the liquid helium vessel relief device for the Alpha Magnetic Spectrometer-02 (AMS-02). The relief device utilizes a series of rupture discs designed to open in the event of a vacuum failure of the AMS-02 cryogenic system. A failure of this type is classified to be a catastrophic loss of insulating vacuum accident. This apparatus differs from other approaches due to the size of the test volumes used. The verification apparatus consists of a 250 liter vessel used for the test quantity of liquid helium that is located inside a vacuum insulated vessel. A large diameter valve is suddenly opened to simulate the loss of insulating vacuum in a repeatable manner. Pressure and temperature vs. time data are presented and discussed in the context of the AMS-02 hardware configuration.

  13. 74. LIQUID NITROGEN TANK, REGULATOR VALVES, AND PRESSURE GAUGES FOR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    74. LIQUID NITROGEN TANK, REGULATOR VALVES, AND PRESSURE GAUGES FOR LIQUID NITROGEN PUMPING STATION - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  14. Binary Operation Of A Liquid-Crystal Light Valve

    NASA Technical Reports Server (NTRS)

    Davis, Jeffrey A.

    1990-01-01

    Conditions for operation of commercially available liquid-crystal light valve as binary spatial light modulator discovered. In mode, modulator turns on sharply and then saturates as intensity of writing beam increases. Valve comprises photoconductive layer and liquid-crystal layer separated by dielectric mirror and sandwiched between two transparent electrodes. Potential applications include enhancement of images, optical recording, and holography.

  15. Novel liquid equilibrium valving on centrifugal microfluidic CD platform.

    PubMed

    Al-Faqheri, Wisam; Ibrahim, Fatimah; Thio, Tzer Hwai Gilbert; Arof, Hamzah; Madou, Marc

    2013-01-01

    One of the main challenges faced by researchers in the field of microfluidic compact disc (CD) platforms is the control of liquid movement and sequencing during spinning. This paper presents a novel microfluidic valve based on the principle of liquid equilibrium on a rotating CD. The proposed liquid equilibrium valve operates by balancing the pressure produced by the liquids in a source and a venting chamber during spinning. The valve does not require external forces or triggers, and is able to regulate burst frequencies with high accuracy. In this work, we demonstrate that the burst frequency can be significantly raised by making just a small adjustment of the liquid height in the vent chamber. Finally, the proposed valve ng method can be used separately or combined with other valving methods in advance microfluidic processes.

  16. Pickering NGS 1990 vacuum building outage: Inspection of pressure-relief -valve diaphragms. Report No. 90-203-K

    SciTech Connect

    Lewak, R.J.

    1990-01-01

    This report details the Pickering Nuclear Generating Station inspection of the replacement of both upper and lower neoprene rolling diaphragms with EPDM (Ethylene-Propylene-Diene Monomer) rolling diaphragms in the pressure relief valves which isolate the atmosphere of the pressure relief duct from that of the vacuum building.

  17. Computational Modeling of Liquid and Gaseous Control Valves

    NASA Technical Reports Server (NTRS)

    Daines, Russell; Ahuja, Vineet; Hosangadi, Ashvin; Shipman, Jeremy; Moore, Arden; Sulyma, Peter

    2005-01-01

    In this paper computational modeling efforts undertaken at NASA Stennis Space Center in support of rocket engine component testing are discussed. Such analyses include structurally complex cryogenic liquid valves and gas valves operating at high pressures and flow rates. Basic modeling and initial successes are documented, and other issues that make valve modeling at SSC somewhat unique are also addressed. These include transient behavior, valve stall, and the determination of flow patterns in LOX valves. Hexahedral structured grids are used for valves that can be simplifies through the use of axisymmetric approximation. Hybrid unstructured methodology is used for structurally complex valves that have disparate length scales and complex flow paths that include strong swirl, local recirculation zones/secondary flow effects. Hexahedral (structured), unstructured, and hybrid meshes are compared for accuracy and computational efficiency. Accuracy is determined using verification and validation techniques.

  18. Evaluation by step response tests of prototype relief valves designed for YF-12 inlet stability bleed system

    NASA Technical Reports Server (NTRS)

    Dustin, M. O.; Neiner, G. H.

    1975-01-01

    Two stability bleed system relief valves were tested in a special dynamic test facility. These poppet valves are prototypes for a stability bleed system designed for use in a YF-12 flight inlet. One valve is unshielded, while the other has a special shield to eliminate the flow effect pressures on the piston. The tests determined the size of a damping orifice to be used during wind tunnel tests of the bleed system and verified an analog simulation of the valves. The effects of initial pressure level, pressure step size, and spring rate were investigated.

  19. The optimization of design parameters for surge relief valve for pipeline systems

    NASA Astrophysics Data System (ADS)

    Kim, Hyunjun; Hur, Jisung; Kim, Sanghyun

    2017-06-01

    Surge is an abnormal pressure which induced by rapid changes of flow rate in pipeline systems. In order to protect pipeline system from the surge pressure, various hydraulic devices have been developed. Surge-relief valve(SRV) is one of the widely applied devices to control surge due to its feasibility in application, efficiency and cost-effectiveness. SRV is designed to automatically open under abnormal pressure and discharge the flow and makes pressure of the system drop to the allowable level. The performance of the SRV is influenced by hydraulics. According to previous studies, there are several affecting factors which determine performance of the PRV such as design parameters (e.g. size of the valve), system parameters (e.g. number of the valves and location of the valve), and operation parameters (e.g. set point and operation time). Therefore, the systematic consideration for factors affecting performance of SRV is required for the proper installation of SRV in the system. In this study, methodology for finding optimum parameters of the SRV is explored through the integration of Genetic Algorithm(GA) into surge analysis.

  20. Investigation Of Adhesion Formation In New Stainless Steel Trim Spring Operated Pressure Relief Valves

    SciTech Connect

    Gross, Robert E.; Bukowski, Julia V.; Goble, William M.

    2013-04-16

    Examination of proof test data for new (not previously installed) stainless steel (SS) trim spring operated pressure relief valves (SOPRV) reveals that adhesions form between the seat and disc in about 46% of all such SOPRV. The forces needed to overcome these adhesions can be sufficiently large to cause the SOPRV to fail its proof test (FPT) prior to installation. Furthermore, a significant percentage of SOPRV which are found to FPT are also found to ''fail to open'' (FTO) meaning they would not relief excess pressure in the event of an overpressure event. The cases where adhesions result in FTO or FPT appear to be confined to SOPRV with diameters < 1 in and set pressures < 150 psig and the FTO are estimated to occur in 0.31% to 2.00% of this subpopulation of SS trim SOPRV. The reliability and safety implications of these finding for end-users who do not perform pre-installation testing of SOPRV are discussed.

  1. Helium pressures in RHIC vacuum cryostats and relief valve requirements from magnet cooling line failure

    SciTech Connect

    Liaw, C.J.; Than, Y.; Tuozzolo, J.

    2011-03-28

    A catastrophic failure of the RHIC magnet cooling lines, similar to the LHC superconducting bus failure incident, would pressurize the insulating vacuum in the magnet and transfer line cryostats. Insufficient relief valves on the cryostats could cause a structural failure. A SINDA/FLUINT{reg_sign} model, which simulated the 4.5K/4 atm helium flowing through the magnet cooling system distribution lines, then through a line break into the vacuum cryostat and discharging via the reliefs into the RHIC tunnel, had been developed to calculate the helium pressure inside the cryostat. Arc flash energy deposition and heat load from the ambient temperature cryostat surfaces were included in the simulations. Three typical areas: the sextant arc, the Triplet/DX/D0 magnets, and the injection area, had been analyzed. Existing relief valve sizes were reviewed to make sure that the maximum stresses, caused by the calculated maximum pressures inside the cryostats, did not exceed the allowable stresses, based on the ASME Code B31.3 and ANSYS results. The conclusions are as follows: (1) The S/F simulation results show that the highest internal pressure in the cryostats, due to the magnet line failure, is {approx}37 psig (255115 Pa); (2) Based on the simulation, the temperature on the cryostat chamber, INJ Q8-Q9, could drop to 228 K, which is lower than the material minimum design temperature allowed by the Code; (3) Based on the ASME Code and ANSYS results, the reliefs on all the cryostats inside the RHIC tunnel are adequate to protect the vacuum chambers when the magnet cooling lines fail; and (4) In addition to the pressure loading, the thermal deformations, due to the temperature decrease on the cryostat chambers, could also cause a high stress on the chamber, if not properly supported.

  2. Liquid-fuel valve with precise throttling control

    NASA Technical Reports Server (NTRS)

    Mcdougal, A. R.; Porter, R. N.; Riebling, R. W.

    1971-01-01

    Prototype liquid-fuel valve performs on-off and throttling functions in vacuum without component cold-welding or excessive leakage. Valve design enables simple and rapid disassembly and parts replacement and operates with short working stroke, providing maximum throttling sensitivity commensurate with good control.

  3. 16. DETAIL SHOWING LIQUID OXYGEN TANK FOURTEENINCH BALL VALVE. Looking ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    16. DETAIL SHOWING LIQUID OXYGEN TANK FOURTEEN-INCH BALL VALVE. Looking southwest. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  4. 17. DETAIL, FOURTEENINCH LIQUID OXYGEN BALL VALVE. Looking south southeast. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. DETAIL, FOURTEEN-INCH LIQUID OXYGEN BALL VALVE. Looking south southeast. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  5. 137. VALVES ON SOUTH WALL OF LIQUID NITROGEN CONTROL ROOM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    137. VALVES ON SOUTH WALL OF LIQUID NITROGEN CONTROL ROOM (115), LSB (BLDG. 770) - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  6. 99. LIQUID OXYGEN LINE AND SAMPLING VALVE FOR RAPIDLOAD ON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    99. LIQUID OXYGEN LINE AND SAMPLING VALVE FOR RAPID-LOAD ON WEST SIDE OF SKID 9A - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  7. The Effects of Maintenance Actions on the PFDavg of Spring Operated Pressure Relief Valves

    DOE PAGES

    Harris, S.; Gross, R.; Goble, W; ...

    2015-12-01

    The safety integrity level (SIL) of equipment used in safety instrumented functions is determined by the average probability of failure on demand (PFDavg) computed at the time of periodic inspection and maintenance, i.e., the time of proof testing. The computation of PFDavg is generally based solely on predictions or estimates of the assumed constant failure rate of the equipment. However, PFDavg is also affected by maintenance actions (or lack thereof) taken by the end user. This paper shows how maintenance actions can affect the PFDavg of spring operated pressure relief valves (SOPRV) and how these maintenance actions may be accountedmore » for in the computation of the PFDavg metric. The method provides a means for quantifying the effects of changes in maintenance practices and shows how these changes impact plant safety.« less

  8. THE EFFECTS OF MAINTENANCE ACTIONS ON THE PFDavg OF SPRING OPERATED PRESSURE RELIEF VALVES

    SciTech Connect

    Harris, S.; Gross, R.

    2014-04-01

    The safety integrity level (SIL) of equipment used in safety instrumented functions is determined by the average probability of failure on demand (PFDavg) computed at the time of periodic inspection and maintenance, i.e., the time of proof testing. The computation of PFDavg is generally based solely on predictions or estimates of the assumed constant failure rate of the equipment. However, PFDavg is also affected by maintenance actions (or lack thereof) taken by the end user. This paper shows how maintenance actions can affect the PFDavg of spring operated pressure relief valves (SOPRV) and how these maintenance actions may be accounted for in the computation of the PFDavg metric. The method provides a means for quantifying the effects of changes in maintenance practices and shows how these changes impact plant safety.

  9. The Effects of Maintenance Actions on the PFDavg of Spring Operated Pressure Relief Valves

    SciTech Connect

    Harris, S.; Gross, R.; Goble, W; Bukowski, J

    2015-12-01

    The safety integrity level (SIL) of equipment used in safety instrumented functions is determined by the average probability of failure on demand (PFDavg) computed at the time of periodic inspection and maintenance, i.e., the time of proof testing. The computation of PFDavg is generally based solely on predictions or estimates of the assumed constant failure rate of the equipment. However, PFDavg is also affected by maintenance actions (or lack thereof) taken by the end user. This paper shows how maintenance actions can affect the PFDavg of spring operated pressure relief valves (SOPRV) and how these maintenance actions may be accounted for in the computation of the PFDavg metric. The method provides a means for quantifying the effects of changes in maintenance practices and shows how these changes impact plant safety.

  10. Proportional liquid-nitrogen valve and control system

    NASA Astrophysics Data System (ADS)

    Christman, S. B.

    1990-09-01

    A proportional magnetic valve has been developed that permits continuous flow of cryogenic fluids and gases. The proportional valve (PV) may be electrically controlled in the manual mode (open loop current drive) or in the automatic mode (closed loop current drive). A complete control system for liquid-nitrogen (LN) flow control applications is described. The system includes alarm and automatic supply tank switching features.

  11. Smectic A and C* liquid crystal light valves

    NASA Astrophysics Data System (ADS)

    Dupont, L.; Wu, Z. Y.; Cambon, P.; de Bougrenet de La Tocnaye, J. L.

    1993-07-01

    The development of light valves for application in the domain of imaging and information display has benefited from simultaneous advances in liquid crystal materials. We will focus on recent developments involving the use of smectic A and smectic C*. Two types of light valves are described with their addressing technology. The first one is optically addressed spatial light modulator: optical information is converted into electric information through the medium of a photoconductivity material layer (amorphous silicon). The second type of valve is a VLSI chip covered with liquid crystal which can be optically addressed on each pixel and perform local electronic processing. The local switching of the liquid crystal allows the reading of the final state. Le développement des valves optiques dans le domaine de l'image et la représentation spatiale de l'information a bénéficié des progrès réalisés sur les matériaux “cristaux liquides". Nous allons étudier tout spécialement les développements récents concernant l'utilisation des phases smectiques A et C*. Deux types de valves sont décrites avec leurs modes d'adressage respectifs : le modulateur à adressage optique : l'information est envoyée par voie optique et la commutation s'effectue par la conversion du signal optique en signal électrique grâce à une couche d'un matériau photoconducteur (silicium amorphe hydrogéné). Le deuxième type de valve est un circuit VLSI recouvert de cristal liquide pouvant être adressé par voie optique et effectuant un traitement logique local de l'information reçue ; la commutation locale du cristal liquide permet alors la lecture de l'état final.

  12. VALIDATION OF SPRING OPERATED PRESSURE RELIEF VALVE TIME TO FAILURE AND THE IMPORTANCE OF STATISTICALLY SUPPORTED MAINTENANCE INTERVALS

    SciTech Connect

    Gross, R; Stephen Harris, S

    2009-02-18

    The Savannah River Site operates a Relief Valve Repair Shop certified by the National Board of Pressure Vessel Inspectors to NB-23, The National Board Inspection Code. Local maintenance forces perform inspection, testing, and repair of approximately 1200 spring-operated relief valves (SORV) each year as the valves are cycled in from the field. The Site now has over 7000 certified test records in the Computerized Maintenance Management System (CMMS); a summary of that data is presented in this paper. In previous papers, several statistical techniques were used to investigate failure on demand and failure rates including a quantal response method for predicting the failure probability as a function of time in service. The non-conservative failure mode for SORV is commonly termed 'stuck shut'; industry defined as the valve opening at greater than or equal to 1.5 times the cold set pressure. Actual time to failure is typically not known, only that failure occurred some time since the last proof test (censored data). This paper attempts to validate the assumptions underlying the statistical lifetime prediction results using Monte Carlo simulation. It employs an aging model for lift pressure as a function of set pressure, valve manufacturer, and a time-related aging effect. This paper attempts to answer two questions: (1) what is the predicted failure rate over the chosen maintenance/ inspection interval; and do we understand aging sufficient enough to estimate risk when basing proof test intervals on proof test results?

  13. Analysis of operational methane emissions from pressure relief valves from biogas storages of biogas plants.

    PubMed

    Reinelt, Torsten; Liebetrau, Jan; Nelles, Michael

    2016-10-01

    The study presents the development of a method for the long term monitoring of methane emissions from pressure relief valves (PRV(1)) of biogas storages, which has been verified during test series at two PRVs of two agricultural biogas plants located in Germany. The determined methane emission factors are 0.12gCH4kWhel(-1) (0.06% CH4-loss, within 106days, 161 triggering events, winter season) from biogas plant A and 6.80/7.44gCH4kWhel(-1) (3.60/3.88% CH4-loss, within 66days, 452 triggering events, summer season) from biogas plant B. Besides the operational state of the biogas plant (e.g. malfunction of the combined heat and power unit), the mode of operation of the biogas flare, which can be manually or automatically operated as well as the atmospheric conditions (e.g. drop of the atmospheric pressure) can also affect the biogas emission from PRVs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Riser-relief valve dynamic interactions (extension to a previous model)

    SciTech Connect

    Botros, K.K.; Dunn, G.H.; Hrycyk, J.A.

    1998-05-01

    Further investigation of the dynamic stability behavior of a typical pilot-operated relief valve is reported. The present study is an extension to Botros et al. (1997) model, which includes mapping of the oscillating frequencies and amplitudes with riser dimensionless length L/D; inclusion of the effects of a wedge-O-ring seal in the model; detailed analyses of the field tests revealing unknown values for model parameters. These model refinements resulted in a better agreement between simulation results and field measurements. Analysis of piston oscillation frequencies and amplitudes indicates that the piston oscillation frequency mirrors the riser`s one-quarter-wave resonance frequency for lower values of L/D. At L/D = 20 and higher, two modes of oscillations started to emerge with two distinct frequencies. Maximum oscillation amplitudes occurred at L/D corresponding to one-quarter wave. Wedge-O-ring seal mechanism helps in suppressing piston oscillations; but it must be used in conjunction with a proper lubricant, otherwise the piston may jam partway during the upward stroke.

  15. Ineffectiveness of using the pressure relief valve technique during cuff inflation

    PubMed Central

    Annoni, Raquel; Pires-Neto, Ruy Camargo

    2014-01-01

    Objective To test the effectiveness of using a cuff pressure relief valve technique to maintain cuff pressure levels within the normal in vitro range (Phase 1) in patients admitted to the intensive care unit (Phase 2) and to test the reproducibility of the technique using different syringes. Methods In Phase 1, a tracheal tube was inserted into a trachea model. Ten- and 20mL syringes were used to inflate the cuff through the tracheal tube. The cuff was slowly and steadily inflated until the syringe plunger would move in the opposite direction of the application. After the plunger stopped, the cuff pressures were recorded. In Phase 2, the same maneuvers for inflating the cuff were performed on 20 patients using 5, 10, and 20mL syringes and were compared with manometer measurements. The intraclass correlation coefficient and Bland-Altman analysis were employed to determine the reproducibility and agreement between syringes. Data were expressed as medians (interquartile range). Results There was no reproducibility between syringes with an intraclass correlation coefficient ranging between -0.33 and 0.8 (p>0.05). The pressures generated with the syringes were higher than the pressures generated using a standard manometer: the 5mL syringe pressure was 105cmH2O (82.5-120cmH2O), the 10mL syringe pressure was 69cmH2O (47.5-111.3cmH2O), and the 20mL syringe pressure was 45cmH2O (35-59.5cmH2O). The Bland-Altman analysis confirmed the large bias and variability between the syringes used, compared with the manometer. Conclusion The use of syringes is not an effective technique for determining the cuff pressure in patients admitted to the intensive care unit. PMID:25607265

  16. Liquid-Crystal Light Valve Enhances Edges In Images

    NASA Technical Reports Server (NTRS)

    Chao, Tien-Hsin; Liu, Hua-Kuang

    1991-01-01

    Experiments show liquid-crystal light valve (LCLV) exhibits operating mode in which it enhances edges in images projected on it. Operates in edge-enhancing mode (or in combination of edge-enhancing and normal modes) by suitably adjusting bias voltage and frequency. Enhancement of edges one of most important preprocessing steps in optical pattern-recognition systems. Incorporated into image-processing system to enhance edges without introducing excessive optical noise.

  17. Research on the water hammer protection of the long distance water supply project with the combined action of the air vessel and over-pressure relief valve

    NASA Astrophysics Data System (ADS)

    Li, D. D.; Jiang, J.; Zhao, Z.; Yi, W. S.; Lan, G.

    2013-12-01

    We take a concrete pumping station as an example in this paper. Through the calculation of water hammer protection with a specific pumping station water supply project, and the analysis of the principle, mathematical models and boundary conditions of air vessel and over-pressure relief valve we show that the air vessel can protect the water conveyance system and reduce the transient pressure damage due to various causes. Over-pressure relief valve can effectively reduce the water hammer because the water column re-bridge suddenly stops the pump and prevents pipeline burst. The paper indicates that the combination set of air vessel and over-pressure relief valve can greatly reduce the quantity of the air valve and can eliminate the water hammer phenomenon in the pipeline system due to the vaporization and water column separation and re-bridge. The conclusion could provide a reference for the water hammer protection of long-distance water supply system.

  18. Schottky diode silicon liquid-crystal light valve

    NASA Astrophysics Data System (ADS)

    Sayyah, Keyvan; Efron, Uzi; Forber, Richard A.; Goodwin, Norman W.; Reif, Philip G.

    1991-06-01

    The authors report the operation of the Hughes Schottky diode-based silicon liquid crystal light valve (SLV) using readout light in the visible region. Limiting resolutions of 28 lp/mm limited by the Schottky diode periodicity, contrast ratios of >100:1, visible input light sensitivities of better than 50 (mu) W/cm2, and response times as fast as 5 ms have been measured. Both standard twisted nematic and homeotropically-aligned liquid crystal configurations have been utilized. The main parameter of this device is the leakage current of the Schottky diodes.

  19. ESTIMATED SIL LEVELS AND RISK COMPARISONS FOR RELIEF VALVES AS A FUNCTION OF TIME-IN-SERVICE

    SciTech Connect

    Harris, S.

    2012-03-26

    Risk-based inspection methods enable estimation of the probability of spring-operated relief valves failing on demand at the United States Department of Energy's Savannah River Site (SRS) in Aiken, South Carolina. The paper illustrates an approach based on application of the Frechet and Weibull distributions to SRS and Center for Chemical Process Safety (CCPS) Process Equipment Reliability Database (PERD) proof test results. The methodology enables the estimation of ANSI/ISA-84.00.01 Safety Integrity Levels (SILs) as well as the potential change in SIL level due to modification of the maintenance schedule. Current SRS practices are reviewed and recommendations are made for extending inspection intervals. The paper compares risk-based inspection with specific SILs as maintenance intervals are adjusted. Groups of valves are identified in which maintenance times can be extended as well as different groups in which an increased safety margin may be needed.

  20. 46 CFR 52.01-120 - Safety valves and safety relief valves (modifies PG-67 through PG-73).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... than 51mm (2 in.) NPS. (3) On river steam vessels whose boilers are connected in batteries without means of isolating one boiler from another, each battery of boilers shall be treated as a single boiler... weighted safety valves now installed may be continued in use and may be repaired, but when renewals...

  1. 46 CFR 52.01-120 - Safety valves and safety relief valves (modifies PG-67 through PG-73).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... than 51mm (2 in.) NPS. (3) On river steam vessels whose boilers are connected in batteries without means of isolating one boiler from another, each battery of boilers shall be treated as a single boiler... weighted safety valves now installed may be continued in use and may be repaired, but when renewals...

  2. Liquid crystal light valve technologies for display applications

    NASA Astrophysics Data System (ADS)

    Kikuchi, Hiroshi; Takizawa, Kuniharu

    2001-11-01

    The liquid crystal (LC) light valve, which is a spatial light modulator that uses LC material, is a very important device in the area of display development, image processing, optical computing, holograms, etc. In particular, there have been dramatic developments in the past few years in the application of the LC light valve to projectors and other display technologies. Various LC operating modes have been developed, including thin film transistors, MOS-FETs and other active matrix drive techniques to meet the requirements for higher resolution, and substantial improvements have been achieved in the performance of optical systems, resulting in brighter display images. Given this background, the number of applications for the LC light valve has greatly increased. The resolution has increased from QVGA (320 x 240) to QXGA (2048 x 1536) or even super- high resolution of eight million pixels. In the area of optical output, projectors of 600 to 13,000 lm are now available, and they are used for presentations, home theatres, electronic cinema and other diverse applications. Projectors using the LC light valve can display high- resolution images on large screens. They are now expected to be developed further as part of hyper-reality visual systems. This paper provides an overview of the needs for large-screen displays, human factors related to visual effects, the way in which LC light valves are applied to projectors, improvements in moving picture quality, and the results of the latest studies that have been made to increase the quality of images and moving images or pictures.

  3. Reflective liquid crystal light valve with hybrid field effect mode

    NASA Technical Reports Server (NTRS)

    Boswell, Donald D. (Inventor); Grinberg, Jan (Inventor); Jacobson, Alexander D. (Inventor); Myer, Gary D. (Inventor)

    1977-01-01

    There is disclosed a high performance reflective mode liquid crystal light valve suitable for general image processing and projection and particularly suited for application to real-time coherent optical data processing. A preferred example of the device uses a CdS photoconductor, a CdTe light absorbing layer, a dielectric mirror, and a liquid crystal layer sandwiched between indium-tin-oxide transparent electrodes deposited on optical quality glass flats. The non-coherent light image is directed onto the photoconductor; this reduces the impedance of the photoconductor, thereby switching the AC voltage that is impressed across the electrodes onto the liquid crystal to activate the device. The liquid crystal is operated in a hybrid field effect mode. It utilizes the twisted nematic effect to create a dark off-state (voltage off the liquid crystal) and the optical birefringence effect to create the bright on-state. The liquid crystal thus modulates the polarization of the coherent read-out or projection light responsively to the non-coherent image. An analyzer is used to create an intensity modulated output beam.

  4. 49 CFR 178.338-8 - Pressure relief devices, piping, valves, and fittings.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Schedule 80 weight or heavier. Malleable metals must be used in the construction of valves and fittings. Where copper tubing is permitted, joints shall be brazed or be of equally strong metal union type. The...

  5. 49 CFR 178.338-8 - Pressure relief devices, piping, valves, and fittings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... be Schedule 80 weight or heavier. Malleable metals must be used in the construction of valves and fittings. Where copper tubing is permitted, joints shall be brazed or be of equally strong metal union...

  6. 49 CFR 178.338-8 - Pressure relief devices, piping, valves, and fittings.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...) SPECIFICATIONS FOR PACKAGINGS Specifications for Containers for Motor Vehicle Transportation § 178.338-8 Pressure..., jarring, and vibration. Slip joints are not authorized for this purpose. (5) All piping, valves and...

  7. 49 CFR 178.338-8 - Pressure relief devices, piping, valves, and fittings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...) SPECIFICATIONS FOR PACKAGINGS Specifications for Containers for Motor Vehicle Transportation § 178.338-8 Pressure..., jarring, and vibration. Slip joints are not authorized for this purpose. (5) All piping, valves and...

  8. 46 CFR 56.50-25 - Safety and relief valve escape piping.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... discharging thereto and shall be led as near vertically as practicable to the atmosphere. (b) Expansion joints... valve discharges, when permitted to terminate in the machinery space, shall be led below the...

  9. 46 CFR 56.50-25 - Safety and relief valve escape piping.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... discharging thereto and shall be led as near vertically as practicable to the atmosphere. (b) Expansion joints... valve discharges, when permitted to terminate in the machinery space, shall be led below the...

  10. 46 CFR 56.50-25 - Safety and relief valve escape piping.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... discharging thereto and shall be led as near vertically as practicable to the atmosphere. (b) Expansion joints... valve discharges, when permitted to terminate in the machinery space, shall be led below the...

  11. 46 CFR 56.50-25 - Safety and relief valve escape piping.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... discharging thereto and shall be led as near vertically as practicable to the atmosphere. (b) Expansion joints... valve discharges, when permitted to terminate in the machinery space, shall be led below the...

  12. Analysis of Flow in Pilot Operated Safety and Relief Valve of Nuclear Reactor Coolant System

    SciTech Connect

    Kwon, Soon-Bum; Lee, Dong-Won; Kim, In-Goo; Ahn, Hyung-Joon; Kim, Hho-Jung

    2004-07-01

    When the POSRV equipped in a nuclear power plant opens in instant by a failure in coolant system of PWR, a moving shock wave generates, and propagates downstream of the valve, inducing a complicated unsteadiness. The moving shock wave may exert severe load to the structure. In this connection, a method of gradual opening of the valve is used to reduce the load acting on the wall at the downstream of the POSRV. In the present study, experiments and calculations are performed to investigate the detail unsteady flow at the various pipe units and the effect of valve opening time on the flow downstream of the valve. In calculation by using of air as working fluid, 2-dimensional, unsteady compressible Navier-Stokes equations are solved by finite volume method. It was found that when the incident shock wave passes through the pipe unit, it may experience diffraction, reflection and interaction with a vortex. Furthermore, the geometry of the pipe unit affects the reflection type of shock wave and changes the load acting on the wall of pipe unit. It was also turned out that the maximum force acting on the wall of the pipe unit becomes in order of T-junction, 108 deg. elbow and branch in magnitude, respectively. And, the results obtained that show that the rapid pressure rise due to the moving shock wave by instant POSRV valve opening is attenuated by employing the gradual opening. (authors)

  13. 40 CFR 264.1057 - Standards: Valves in gas/vapor service or in light liquid -service.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...: Valves in gas/vapor service or in light liquid -service. (a) Each valve in gas/vapor or light liquid... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Standards: Valves in gas/vapor service or in light liquid -service. 264.1057 Section 264.1057 Protection of Environment ENVIRONMENTAL...

  14. 40 CFR 264.1057 - Standards: Valves in gas/vapor service or in light liquid -service.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...: Valves in gas/vapor service or in light liquid -service. (a) Each valve in gas/vapor or light liquid... 40 Protection of Environment 26 2011-07-01 2011-07-01 false Standards: Valves in gas/vapor service or in light liquid -service. 264.1057 Section 264.1057 Protection of Environment...

  15. 40 CFR 264.1057 - Standards: Valves in gas/vapor service or in light liquid -service.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...: Valves in gas/vapor service or in light liquid -service. (a) Each valve in gas/vapor or light liquid... 40 Protection of Environment 27 2012-07-01 2012-07-01 false Standards: Valves in gas/vapor service or in light liquid -service. 264.1057 Section 264.1057 Protection of Environment...

  16. 40 CFR 264.1057 - Standards: Valves in gas/vapor service or in light liquid -service.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...: Valves in gas/vapor service or in light liquid -service. (a) Each valve in gas/vapor or light liquid... 40 Protection of Environment 27 2013-07-01 2013-07-01 false Standards: Valves in gas/vapor service or in light liquid -service. 264.1057 Section 264.1057 Protection of Environment...

  17. 40 CFR 264.1057 - Standards: Valves in gas/vapor service or in light liquid -service.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...: Valves in gas/vapor service or in light liquid -service. (a) Each valve in gas/vapor or light liquid... 40 Protection of Environment 26 2014-07-01 2014-07-01 false Standards: Valves in gas/vapor service or in light liquid -service. 264.1057 Section 264.1057 Protection of Environment...

  18. 49 CFR 178.337-9 - Pressure relief devices, piping, valves, hoses, and fittings.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... chlorine service, see paragraph (b)(7) of this section. (2) Pipe joints must be threaded, welded, or... subchapter. (iii) Mark each hose assembly with the month and year of its original pressure test. (8) Chlorine cargo tanks. Angle valves on cargo tanks intended for chlorine service must conform to the standards...

  19. 49 CFR 178.337-9 - Pressure relief devices, piping, valves, hoses, and fittings.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... chlorine service, see paragraph (b)(7) of this section. (2) Pipe joints must be threaded, welded, or... subchapter. (iii) Mark each hose assembly with the month and year of its original pressure test. (8) Chlorine cargo tanks. Angle valves on cargo tanks intended for chlorine service must conform to the standards...

  20. TRACE and TRAC-BF1 benchmark against Leibstadt plant data during the event inadvertent opening of relief valves

    SciTech Connect

    Sekhri, A.; Baumann, P.; Wicaksono, D.; Miro, R.; Barrachina, T.; Verdu, G.

    2012-07-01

    In framework of introducing TRACE code to transient analyses system codes for Leibstadt Power Plant (KKL), a conversion process of existing TRAC-BF1 model to TRACE has been started within KKL. In the first step, TRACE thermal-hydraulic model for KKL has been developed based on existing TRAC-BF1 model. In order to assess the code models a simulation of plant transient event is required. In this matter simulations of inadvertent opening of 8 relief valves event have been performed. The event occurs at KKL during normal operation, and it started when 8 relief valves open resulting in depressurization of the Reactor Pressure Vessel (RPV). The reactor was shutdown safely by SCRAM at low level. The high pressure core spray (HPCS) and the reactor core isolation cooling (RCIC) have been started manually in order to compensate the level drop. The remaining water in the feedwater (FW) lines flashes due to saturation conditions originated from RPV depressurization and refills the reactor downcomer. The plant boundary conditions have been used in the simulations and the FW flow rate has been adjusted for better prediction. The simulations reproduce the plant data with good agreement. It can be concluded that the TRAC-BF1 existing model has been used successfully to develop the TRACE model and the results of the calculations have shown good agreement with plant recorded data. Beside the modeling assessment, the TRACE and TRAC-BF1 capabilities to reproduce plant physical behavior during the transient have shown satisfactory results. The first step of developing KKL model for TRACE has been successfully achieved and this model is further developed in order to simulate more complex plant behavior such as Turbine Trip. (authors)

  1. Infrared sensitive liquid crystal light valve with semiconductor substrate.

    PubMed

    Shcherbin, Konstantin; Gvozdovskyy, Igor; Evans, Dean R

    2016-02-10

    A liquid crystal light valve (LCLV) is an optically controlled spatial light modulator that allows recording of dynamic holograms. Almost all known LCLVs operate in the visible range of the spectrum. In the present work we demonstrate a LCLV operating in the infrared. The interaction of signal and pump waves is studied for different applied voltages, grating spacings, and intensities of the recording beams. A fourfold amplification of the weak signal beam is achieved. The amplitude of the refractive index modulation Δn=0.007 and nonlinear coupling constant n₂=-1  cm²/W are estimated from the experimental results. External phase modulation of one of the recording beams is used for a further transient increase of the signal beam gain.

  2. Emergency relief venting of the infrared telescope liquid helium dewar, second edition

    NASA Astrophysics Data System (ADS)

    Urban, E. W.

    1981-04-01

    An updated analysis is made of the emergency relief venting of the liquid helium dewar of the Spacelab 2 Infrared Telescope experiment in the event of a massive failure of the dewar guard vacuum. Such a failure, resulting from a major accident, could cause rapid heating and pressurization of the liquid helium in the dewar and lead to relief venting through the emergency relief system. The heat input from an accident is estimated for various fluid conditions in the dewar and the relief process considered as it takes place through one or both of the emergency relief paths. It was previously assumed that the burst diaphragms in the dewar relief paths would rupture at a pressure of 65 psi differential or 4.4 atmospheres. In fact, it has proved necessary to use burst diaphragms in the dewar which rupture at 115 psid or 7.8 atmospheres. An analysis of this case was carried out and shows that when the high pressure diaphragm rupture occurs, the dewar pressure falls within 8 s to below the 4.4 atmospheres for which the original analysis was performed, and thereafter it remains below that level.

  3. Emergency relief venting of the infrared telescope liquid helium dewar, second edition

    NASA Technical Reports Server (NTRS)

    Urban, E. W.

    1981-01-01

    An updated analysis is made of the emergency relief venting of the liquid helium dewar of the Spacelab 2 Infrared Telescope experiment in the event of a massive failure of the dewar guard vacuum. Such a failure, resulting from a major accident, could cause rapid heating and pressurization of the liquid helium in the dewar and lead to relief venting through the emergency relief system. The heat input from an accident is estimated for various fluid conditions in the dewar and the relief process considered as it takes place through one or both of the emergency relief paths. It was previously assumed that the burst diaphragms in the dewar relief paths would rupture at a pressure of 65 psi differential or 4.4 atmospheres. In fact, it has proved necessary to use burst diaphragms in the dewar which rupture at 115 psid or 7.8 atmospheres. An analysis of this case was carried out and shows that when the high pressure diaphragm rupture occurs, the dewar pressure falls within 8 s to below the 4.4 atmospheres for which the original analysis was performed, and thereafter it remains below that level.

  4. Navier-Stokes flow field analysis of compressible flow in a high pressure safety relief valve

    NASA Technical Reports Server (NTRS)

    Vu, Bruce; Wang, Ten-See; Shih, Ming-Hsin; Soni, Bharat

    1993-01-01

    The objective of this study is to investigate the complex three-dimensional flowfield of an oxygen safety pressure relieve valve during an incident, with a computational fluid dynamic (CFD) analysis. Specifically, the analysis will provide a flow pattern that would lead to the expansion of the eventual erosion pattern of the hardware, so as to combine it with other findings to piece together a most likely scenario for the investigation. The CFD model is a pressure based solver. An adaptive upwind difference scheme is employed for the spatial discretization, and a predictor, multiple corrector method is used for the velocity-pressure coupling. The computational result indicated vortices formation near the opening of the valve which matched the erosion pattern of the damaged hardware.

  5. 40 CFR 265.1057 - Standards: Valves in gas/vapor service or in light liquid service.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ....1057 Standards: Valves in gas/vapor service or in light liquid service. (a) Each valve in gas/vapor or... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Standards: Valves in gas/vapor service or in light liquid service. 265.1057 Section 265.1057 Protection of Environment ENVIRONMENTAL...

  6. 40 CFR 63.168 - Standards: Valves in gas/vapor service and in light liquid service.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... § 63.168 Standards: Valves in gas/vapor service and in light liquid service. (a) The provisions of this section apply to valves that are either in gas service or in light liquid service. (1) The provisions are... 40 Protection of Environment 9 2011-07-01 2011-07-01 false Standards: Valves in gas/vapor...

  7. 40 CFR 265.1057 - Standards: Valves in gas/vapor service or in light liquid service.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ....1057 Standards: Valves in gas/vapor service or in light liquid service. (a) Each valve in gas/vapor or... 40 Protection of Environment 26 2011-07-01 2011-07-01 false Standards: Valves in gas/vapor service or in light liquid service. 265.1057 Section 265.1057 Protection of Environment...

  8. 40 CFR 60.482-7a - Standards: Valves in gas/vapor service and in light liquid service.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-7a Standards: Valves in gas/vapor service and in light liquid service. (a)(1) Each valve shall be... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards: Valves in gas/vapor service and in light liquid service. 60.482-7a Section 60.482-7a Protection of Environment...

  9. 40 CFR 63.1006 - Valves in gas and vapor service and in light liquid service standards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... § 63.1006 Valves in gas and vapor service and in light liquid service standards. (a) Compliance... requested by the Administrator. For each such demonstration, all valves in gas and vapor and light liquid... 40 Protection of Environment 10 2011-07-01 2011-07-01 false Valves in gas and vapor service and...

  10. 40 CFR 60.482-7a - Standards: Valves in gas/vapor service and in light liquid service.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-7a Standards: Valves in gas/vapor service and in light liquid service. (a)(1) Each valve shall be... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standards: Valves in gas/vapor service and in light liquid service. 60.482-7a Section 60.482-7a Protection of Environment...

  11. 40 CFR 63.168 - Standards: Valves in gas/vapor service and in light liquid service.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... § 63.168 Standards: Valves in gas/vapor service and in light liquid service. (a) The provisions of this section apply to valves that are either in gas service or in light liquid service. (1) The provisions are... 40 Protection of Environment 10 2012-07-01 2012-07-01 false Standards: Valves in gas/vapor...

  12. 40 CFR 63.168 - Standards: Valves in gas/vapor service and in light liquid service.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... § 63.168 Standards: Valves in gas/vapor service and in light liquid service. (a) The provisions of this section apply to valves that are either in gas service or in light liquid service. (1) The provisions are... 40 Protection of Environment 10 2013-07-01 2013-07-01 false Standards: Valves in gas/vapor...

  13. 40 CFR 265.1057 - Standards: Valves in gas/vapor service or in light liquid service.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ....1057 Standards: Valves in gas/vapor service or in light liquid service. (a) Each valve in gas/vapor or... 40 Protection of Environment 27 2013-07-01 2013-07-01 false Standards: Valves in gas/vapor service or in light liquid service. 265.1057 Section 265.1057 Protection of Environment...

  14. 40 CFR 265.1057 - Standards: Valves in gas/vapor service or in light liquid service.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ....1057 Standards: Valves in gas/vapor service or in light liquid service. (a) Each valve in gas/vapor or... 40 Protection of Environment 26 2014-07-01 2014-07-01 false Standards: Valves in gas/vapor service or in light liquid service. 265.1057 Section 265.1057 Protection of Environment...

  15. 40 CFR 63.1006 - Valves in gas and vapor service and in light liquid service standards.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... § 63.1006 Valves in gas and vapor service and in light liquid service standards. (a) Compliance... requested by the Administrator. For each such demonstration, all valves in gas and vapor and light liquid... 40 Protection of Environment 11 2014-07-01 2014-07-01 false Valves in gas and vapor service and...

  16. 40 CFR 63.168 - Standards: Valves in gas/vapor service and in light liquid service.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... § 63.168 Standards: Valves in gas/vapor service and in light liquid service. (a) The provisions of this section apply to valves that are either in gas service or in light liquid service. (1) The provisions are... 40 Protection of Environment 10 2014-07-01 2014-07-01 false Standards: Valves in gas/vapor...

  17. 40 CFR 63.1006 - Valves in gas and vapor service and in light liquid service standards.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... § 63.1006 Valves in gas and vapor service and in light liquid service standards. (a) Compliance... requested by the Administrator. For each such demonstration, all valves in gas and vapor and light liquid... 40 Protection of Environment 11 2012-07-01 2012-07-01 false Valves in gas and vapor service and...

  18. 40 CFR 60.482-7a - Standards: Valves in gas/vapor service and in light liquid service.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-7a Standards: Valves in gas/vapor service and in light liquid service. (a)(1) Each valve shall be... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standards: Valves in gas/vapor service and in light liquid service. 60.482-7a Section 60.482-7a Protection of Environment...

  19. 40 CFR 60.482-7a - Standards: Valves in gas/vapor service and in light liquid service.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-7a Standards: Valves in gas/vapor service and in light liquid service. (a)(1) Each valve shall be... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standards: Valves in gas/vapor service and in light liquid service. 60.482-7a Section 60.482-7a Protection of Environment...

  20. 40 CFR 63.1006 - Valves in gas and vapor service and in light liquid service standards.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... § 63.1006 Valves in gas and vapor service and in light liquid service standards. (a) Compliance... requested by the Administrator. For each such demonstration, all valves in gas and vapor and light liquid... 40 Protection of Environment 11 2013-07-01 2013-07-01 false Valves in gas and vapor service and...

  1. 40 CFR 265.1057 - Standards: Valves in gas/vapor service or in light liquid service.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ....1057 Standards: Valves in gas/vapor service or in light liquid service. (a) Each valve in gas/vapor or... 40 Protection of Environment 27 2012-07-01 2012-07-01 false Standards: Valves in gas/vapor service or in light liquid service. 265.1057 Section 265.1057 Protection of Environment...

  2. Gas flow across a wet screen - Analogy to a relief valve with hysteresis

    NASA Technical Reports Server (NTRS)

    Nachman, A.; Dodge, F. T.

    1983-01-01

    The flow of gas through a wet fine-mesh screen is analyzed in terms of the capillary forces of the liquid wetting the screen and the pressure difference across the screen thickness driving the gas flow. Several different types of time-dependent flow are shown to be possible. The most interesting type is one in which the pressure difference opens small channels in the liquid, which are then closed rapidly by the wetting action of the liquid. The opening and closing exhibit hysteresis, and the flow is highly oscillatory.

  3. Aging and service wear of spring-loaded pressure relief valves used in safety-related systems at nuclear power plants

    SciTech Connect

    Staunton, R.H.; Cox, D.F.

    1995-03-01

    Spring-loaded pressure relief valves (PRVS) are used in some safety-related applications at nuclear power plants. In general, they are used in systems where, during accidents, pressures may rise to levels where pressure safety relief is required for protection of personnel, system piping, and components. This report documents a study of PRV aging and considers the severity and causes of service wear and how it is discovered and corrected in various systems, valve sizes, etc. Provided in this report are results of the examination of the recorded failures and identification of trends and relationships/correlations in the failures when all failure-related parameters are considered. Components that comprise a typical PRV, how those components fail, when they fail, and the current testing frequencies and methods are also presented in detail.

  4. 49 CFR 178.338-8 - Pressure relief devices, piping, valves, and fittings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... fittings must be rated for the maximum tank pressure and suitable for the coldest temperature to which they...-building coil is used on a tank designed to handle oxygen or flammable ladings, the vapor connection to... prevent the loss of vapor from the tank in case of damage to the coil. The liquid connection to that coil...

  5. Technical evaluation report, TMI action NUREG-0737 (II.D.1), relief and safety valve testing, Comanche Peak, Unit 2, Docket No. 50-446

    SciTech Connect

    Fineman, C.P.

    1993-01-01

    In the past, safety and relief valves installed in the primary coolant system of light water reactors have performed improperly. As a result, the authors of NUREG-0578 (TMI-2 Lessons Learned Task Force Status Report and Short-Term Recommendations) and, subsequently, NUREG-0737 (Clarification of TMI Action Plan Requirements) recommended development and completion of programs to do two things. First, the programs should reevaluate the functional performance capabilities of pressurized water reactor safety, relief, and block valves. Second, they should verify the integrity of the pressurizer safety and relief valve piping systems for normal, transient, and accident conditions. This report documents the review of those programs by EG&G Idaho, Inc. Specifically, this report documents the review of the Comanche Peak, Unit 2, Applicant response to the requirements of NUREG-0578 and NUREG-0737. This review found the Applicant provided an acceptable response reconfirming they met General Design Criteria 14, 15, and 30 of Appendix A to 10 CFR 50 for the subject equipment.

  6. Surface relief gratings on polymer dispersed liquid crystals by polarization holography

    SciTech Connect

    Mazzulla, A.; Pagliusi, P.; Provenzano, C.; Russo, G.; Carbone, G.; Cipparrone, G.

    2004-09-27

    We report the observation of surface relief gratings (SRGs) on polymer dispersed liquid crystal films after polarization holographic recording, demonstrating the formation of SRGs in systems without azo compounds, where photoisomerization and chromophore reorientation processes do not occur. Permanent SRGs, several hundred nanometers deep, are recorded on the surface of a polymeric material containing oriented liquid crystal droplets. The results suggest that SRG growth under uniform intensity irradiation is not exclusively related to the photoisomerization, but is a more general phenomenon which can involve different photoinduced chemical and physical mechanisms sensitive to the light polarization state. These effects contribute to the formation of anisotropic structures during the recording process.

  7. Multiplexed hydraulic valve actuation using ionic liquid filled soft channels and Braille displays

    NASA Astrophysics Data System (ADS)

    Gu, Wei; Chen, Hao; Tung, Yi-Chung; Meiners, Jens-Christian; Takayama, Shuichi

    2007-01-01

    Pneumatic actuation with multilayer soft lithography enables operation of up to thousands of valves in parallel using far fewer control lines. However, it is dependent on macroscopic switches and external pressure sources that require interconnects and limit portability. The authors present a more portable and multiplexed valve actuation strategy that uses a grid of mechanically actuated Braille pins to hydraulically, rather than pneumatically, deform elastic actuation channels that act as valves. Experimental and theoretical analyses show that the key to reliable operation of the hydraulic system is the use of nonvolatile ionic liquids as the hydraulic fluid.

  8. VALVE

    DOEpatents

    Arkelyan, A.M.; Rickard, C.L.

    1962-04-17

    A gate valve for controlling the flow of fluid in separate concentric ducts or channels by means of a single valve is described. In one position, the valve sealing discs engage opposed sets of concentric ducts leading to the concentric pipes defining the flow channels to block flow therethrough. In another position, the discs are withdrawn from engagement with the opposed ducts and at the same time a bridging section is interposed therebetween to define concentric paths coextensive with and connecting the opposed ducts to facilitate flow therebetween. A wedge block arrangement is employed with each sealing disc to enable it to engage the ducts. The wedge block arrangement also facilitates unobstructcd withdrawal of the discs out of the intervening space between the sets of ducts. (AEC)

  9. Valve

    DOEpatents

    Cho, Nakwon

    1980-01-01

    A positive acting valve suitable for operation in a corrosive environment is provided. The valve includes a hollow valve body defining an open-ended bore for receiving two, axially aligned, spaced-apart, cylindrical inserts. One insert, designated the seat insert, terminates inside the valve body in an annular face which lies within plane normal to the axis of the two inserts. An elastomeric O-ring seal is disposed in a groove extending about the annular face. The other insert, designated the wedge insert, terminates inside the valve body in at least two surfaces oppositely inclined with respect to each other and with respect to a plane normal to the axis of the two inserts. An elongated reciprocable gate, movable between the two inserts along a path normal to the axis of the two inserts, has a first flat face portion disposed adjacent and parallel to the annular face of the seat insert. The gate has a second face portion opposite to the first face portion provided with at least two oppositely inclined surfaces for mating with respective inclined surfaces of the wedge insert. An opening is provided through the gate which registers with a flow passage through the two inserts when the valve is open. Interaction of the respective inclined surfaces of the gate and wedge insert act to force the first flat face portion of the gate against the O-ring seal in the seat insert at the limits of gate displacement where it reaches its respective fully open and fully closed positions.

  10. 40 CFR 60.482-7 - Standards: Valves in gas/vapor service and in light liquid service.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Before November 7, 2006 § 60.482-7 Standards: Valves in gas/vapor service and in light liquid service. (a... operation in gas/vapor service or light liquid service after the initial startup date for the process unit... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards: Valves in gas/vapor...

  11. 40 CFR 63.1025 - Valves in gas and vapor service and in light liquid service standards.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Standards § 63.1025 Valves in gas and vapor service and in light liquid service standards. (a) Compliance... 40 Protection of Environment 11 2013-07-01 2013-07-01 false Valves in gas and vapor service and in light liquid service standards. 63.1025 Section 63.1025 Protection of Environment...

  12. 40 CFR 63.1025 - Valves in gas and vapor service and in light liquid service standards.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Standards § 63.1025 Valves in gas and vapor service and in light liquid service standards. (a) Compliance... 40 Protection of Environment 11 2012-07-01 2012-07-01 false Valves in gas and vapor service and in light liquid service standards. 63.1025 Section 63.1025 Protection of Environment...

  13. 40 CFR 60.482-7 - Standards: Valves in gas/vapor service and in light liquid service.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Before November 7, 2006 § 60.482-7 Standards: Valves in gas/vapor service and in light liquid service. (a... operation in gas/vapor service or light liquid service after the initial startup date for the process unit... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standards: Valves in gas/vapor...

  14. 40 CFR 60.482-7 - Standards: Valves in gas/vapor service and in light liquid service.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Before November 7, 2006 § 60.482-7 Standards: Valves in gas/vapor service and in light liquid service. (a... operation in gas/vapor service or light liquid service after the initial startup date for the process unit... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standards: Valves in gas/vapor...

  15. 40 CFR 65.106 - Standards: Valves in gas/vapor service and in light liquid service.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Standards: Valves in gas/vapor service and in light liquid service. (a) Compliance schedule. (1) The owner... 40 Protection of Environment 16 2012-07-01 2012-07-01 false Standards: Valves in gas/vapor service and in light liquid service. 65.106 Section 65.106 Protection of Environment ENVIRONMENTAL...

  16. 40 CFR 60.482-7 - Standards: Valves in gas/vapor service and in light liquid service.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Before November 7, 2006 § 60.482-7 Standards: Valves in gas/vapor service and in light liquid service. (a... operation in gas/vapor service or light liquid service after the initial startup date for the process unit... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standards: Valves in gas/vapor...

  17. 40 CFR 65.106 - Standards: Valves in gas/vapor service and in light liquid service.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Standards: Valves in gas/vapor service and in light liquid service. (a) Compliance schedule. (1) The owner... 40 Protection of Environment 16 2013-07-01 2013-07-01 false Standards: Valves in gas/vapor service and in light liquid service. 65.106 Section 65.106 Protection of Environment ENVIRONMENTAL...

  18. 40 CFR 65.106 - Standards: Valves in gas/vapor service and in light liquid service.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Standards: Valves in gas/vapor service and in light liquid service. (a) Compliance schedule. (1) The owner... 40 Protection of Environment 16 2014-07-01 2014-07-01 false Standards: Valves in gas/vapor service and in light liquid service. 65.106 Section 65.106 Protection of Environment ENVIRONMENTAL...

  19. 40 CFR 63.1025 - Valves in gas and vapor service and in light liquid service standards.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Standards § 63.1025 Valves in gas and vapor service and in light liquid service standards. (a) Compliance... 40 Protection of Environment 11 2014-07-01 2014-07-01 false Valves in gas and vapor service and in light liquid service standards. 63.1025 Section 63.1025 Protection of Environment...

  20. Ionogel-based light-actuated valves for controlling liquid flow in micro-fluidic manifolds.

    PubMed

    Benito-Lopez, Fernando; Byrne, Robert; Răduţă, Ana Maria; Vrana, Nihal Engin; McGuinness, Garrett; Diamond, Dermot

    2010-01-21

    We present the fabrication, characterisation and performance of four novel ionic liquid polymer gels (ionogels) as photo-actuated valves incorporated into micro-fluidic manifolds. The ionogels incorporate benzospiropyran units and phosphonium-based ionic liquids. Each ionogel is photo-polymerised in situ in the channels of a poly(methyl methacrylate) micro-fluidic device, generating a manifold incorporating four different micro-valves. The valves are actuated by simply applying localised white light irradiation, meaning that no physical contact between the actuation impulse (light) and the valve structure is required. Through variation of the composition of the ionogels, each of the micro-valves can be tuned to open at different times under similar illumination conditions. Therefore, flows through the manifold can be independently controlled by a single light source. At present, the contraction process to open the channel is relatively rapid (seconds) while the recovery (expansion) process to re-close the channel is relatively slow (minutes), meaning that the valve, in its current form, is better suited for single-actuation events.

  1. Low-voltage binary operation of liquid-crystal Fresnel lens with surface relief structure

    NASA Astrophysics Data System (ADS)

    Chang, Kai-Han; Wang, Dong; Chien, Liang-Chy

    2017-02-01

    We demonstrate a liquid crystal Fresnel lens (LCFL) with a surface relief structure which has the binary switching property and the merit of low voltage driving. The surface relief structure is fabricated by photopolymerization of a polymer-precursor initiated by ultra-violet light onto a solid cylindrical Fresnel lens with desired optical power. A liquid crystal (LC) layer is sandwiched between a pair of polymer Fresnel lens deposited with planar alignment layers with orthogonal rubbing directions. The ordinary refractive index of LC is chose to be close to the refractive index of the polymer. At voltage-off state, when the polarization of light is parallel to the long axis of LC molecules, the refractive index mismatch of liquid crystals and polymer Fresnel lens enables the focusing of LCFL. At voltage-on state, the LCFL is a slab with homogenous refractive index because of the index matching between LC and polymer. With the benefit of twisted nematic structure, the voltage requirement is significantly low ( 6V) for LCFL. The low-voltage binary beam shaping of laser and magnifying lens function using LCFL are experimentally demonstrated in this paper. Polarization-independent LCFL is achievable with a double-layered approach.

  2. Status of the Hughes charge-coupled-device-addressed liquid crystal light valve

    NASA Astrophysics Data System (ADS)

    Welkowsky, M. S.; Efron, Uzi; Byles, W.; Goodwin, N. W.

    1987-05-01

    This paper discusses the present state of development of the Hughes charge-coupled-device-addressed liquid crystal light valve (CCD LCLV). The device is based on the photoactivated silicon LCLV and is suitable for a range of applications, including adaptive optics and as a programmable mask for optical data processing systems.

  3. Postextraction pain relief in children: a clinical trial of liquid analgesics.

    PubMed

    Moore, P A; Acs, G; Hargreaves, J A

    1985-11-01

    Our objective was to evaluate the relative efficacies of four liquid analgesics in children, five to twelve years of age, following dental extractions. The analgesics, acetaminophen elixir (240 or 360 mg), acetaminophen with codeine elixir (240 mg and 24 mg, respectively), aluminum ibuprofen suspension (200 mg), and placebo liquid were administered at home, as a single dose, in a randomized double-blind study design. Of the 154 patients enrolled, 45 were evaluated, 39 patients never required medication, 12 were lost to follow-up, and 8 were excluded for other reasons. Aluminum ibuprofen provided significant relief in one-half hour compared with placebo. At one hour, both aluminum ibuprofen and acetaminophen with codeine provided significant relief compared with placebo. All three active agents were effective at two hours. The global rating of drug efficacy was statistically superior for aluminum ibuprofen. The majority of patients in all four groups were pain-free after four hours. No adverse reactions were reported during the study.

  4. Coincident steam generator tube rupture and stuck-open safety relief valve carryover tests: MB-2 steam generator transient response test program

    SciTech Connect

    Garbett, K; Mendler, O J; Gardner, G C; Garnsey, R; Young, M Y

    1987-03-01

    In PWR steam generator tube rupture (SGTR) faults, a direct pathway for the release of radioactive fission products can exist if there is a coincident stuck-open safety relief valve (SORV) or if the safety relief valve is cycled. In addition to the release of fission products from the bulk steam generator water by moisture carryover, there exists the possibility that some primary coolant may be released without having first mixed with the bulk water - a process called primary coolant bypassing. The MB-2 Phase II test program was designed specifically to identify the processes for droplet carryover during SGTR faults and to provide data of sufficient accuracy for use in developing physical models and computer codes to describe activity release. The test program consisted of sixteen separate tests designed to cover a range of steady-state and transient fault conditions. These included a full SGTR/SORV transient simulation, two SGTR overfill tests, ten steady-state SGTR tests at water levels ranging from very low levels in the bundle up to those when the dryer was flooded, and three moisture carryover tests without SGTR. In these tests the influence of break location and the effect of bypassing the dryer were also studied. In a final test the behavior with respect to aerosol particles in a dry steam generator, appropriate to a severe accident fault, was investigated.

  5. Optical residue addition and storage units using a Hughes liquid crystal light valve

    NASA Technical Reports Server (NTRS)

    Habiby, S. F.; Collins, S. A., Jr.

    1984-01-01

    Optical addition and storage units are described in this paper. These units are implemented using the Hughes Liquid Crystal Light Valve (LCLV) as a spatial light modulator using residue arithmetic for a numerical representation. The main hardware components of the design, besides the light valve, include an array of single-mode optical fibers that provide input information, a polarizing prism in combination with quarter-wave and half-wave retarders for residue arithmetic implementation in the adder, and a holographic array for spatial stability in the storage unit.

  6. Turbulent Motion of Liquids in Hydraulic Resistances with a Linear Cylindrical Slide-Valve.

    PubMed

    Velescu, C; Popa, N C

    2015-01-01

    We analyze the motion of viscous and incompressible liquids in the annular space of controllable hydraulic resistances with a cylindrical linear slide-valve. This theoretical study focuses on the turbulent and steady-state motion regimes. The hydraulic resistances mentioned above are the most frequent type of hydraulic resistances used in hydraulic actuators and automation systems. To study the liquids' motion in the controllable hydraulic resistances with a linear cylindrical slide-valve, the report proposes an original analytic method. This study can similarly be applied to any other type of hydraulic resistance. Another purpose of this study is to determine certain mathematical relationships useful to approach the theoretical functionality of hydraulic resistances with magnetic controllable fluids as incompressible fluids in the presence of a controllable magnetic field. In this report, we established general analytic equations to calculate (i) velocity and pressure distributions, (ii) average velocity, (iii) volume flow rate of the liquid, (iv) pressures difference, and (v) radial clearance.

  7. Turbulent Motion of Liquids in Hydraulic Resistances with a Linear Cylindrical Slide-Valve

    PubMed Central

    Velescu, C.; Popa, N. C.

    2015-01-01

    We analyze the motion of viscous and incompressible liquids in the annular space of controllable hydraulic resistances with a cylindrical linear slide-valve. This theoretical study focuses on the turbulent and steady-state motion regimes. The hydraulic resistances mentioned above are the most frequent type of hydraulic resistances used in hydraulic actuators and automation systems. To study the liquids' motion in the controllable hydraulic resistances with a linear cylindrical slide-valve, the report proposes an original analytic method. This study can similarly be applied to any other type of hydraulic resistance. Another purpose of this study is to determine certain mathematical relationships useful to approach the theoretical functionality of hydraulic resistances with magnetic controllable fluids as incompressible fluids in the presence of a controllable magnetic field. In this report, we established general analytic equations to calculate (i) velocity and pressure distributions, (ii) average velocity, (iii) volume flow rate of the liquid, (iv) pressures difference, and (v) radial clearance. PMID:26167532

  8. One-step photoembossing for submicrometer surface relief structures in liquid crystal semiconductors.

    PubMed

    Liedtke, Alicia; Lei, Chunhong; O'Neill, Mary; Dyer, Peter E; Kitney, Stuart P; Kelly, Stephen M

    2010-06-22

    We report a new single-step method to directly imprint nanometer-scale structures on photoreactive organic semiconductors. A surface relief grating is spontaneously formed when a light-emitting, liquid crystalline, and semiconducting thin film is irradiated by patterned light generated using a phase mask. Grating formation requires no postannealing nor wet etching so there is potential for high-throughput fabrication. The structured film is cross-linked for robustness. Gratings deeper than the original film thickness are made with periods as small as 265 nm. Grating formation is attributed to mass transfer, enhanced by self-assembly, from dark to illuminated regions. A photovoltaic device incorporating the grating is discussed.

  9. Performance Evaluation of a High Bandwidth Liquid Fuel Modulation Valve for Active Combustion Control

    NASA Technical Reports Server (NTRS)

    Saus, Joseph R.; DeLaat, John C.; Chang, Clarence T.; Vrnak, Daniel R.

    2012-01-01

    At the NASA Glenn Research Center, a characterization rig was designed and constructed for the purpose of evaluating high bandwidth liquid fuel modulation devices to determine their suitability for active combustion control research. Incorporated into the rig s design are features that approximate conditions similar to those that would be encountered by a candidate device if it were installed on an actual combustion research rig. The characterized dynamic performance measures obtained through testing in the rig are planned to be accurate indicators of expected performance in an actual combustion testing environment. To evaluate how well the characterization rig predicts fuel modulator dynamic performance, characterization rig data was compared with performance data for a fuel modulator candidate when the candidate was in operation during combustion testing. Specifically, the nominal and off-nominal performance data for a magnetostrictive-actuated proportional fuel modulation valve is described. Valve performance data were collected with the characterization rig configured to emulate two different combustion rig fuel feed systems. Fuel mass flows and pressures, fuel feed line lengths, and fuel injector orifice size was approximated in the characterization rig. Valve performance data were also collected with the valve modulating the fuel into the two combustor rigs. Comparison of the predicted and actual valve performance data show that when the valve is operated near its design condition the characterization rig can appropriately predict the installed performance of the valve. Improvements to the characterization rig and accompanying modeling activities are underway to more accurately predict performance, especially for the devices under development to modulate fuel into the much smaller fuel injectors anticipated in future lean-burning low-emissions aircraft engine combustors.

  10. Motor-operated globe valve performance in a liquid sodium environment

    NASA Astrophysics Data System (ADS)

    Wood, D. H.; Smith, M. S.; Drischler, J. D.

    This study investigates motor-operated globe valve (MOV) performance in a liquid sodium environment as reported to the Centralized Reliability Data Organization (CREDO) from site representatives at several liquid metal reactors and liquid metal test facilities. The CREDO data base contains engineering histories for 179 motor-operated glove valves. Thirty-nine failures have been documented for these components in over 8.7 million hours of operation. The most common MOV events were anomalies with the limit and torque switches, although human initiated problems were also frequent causes of failures. The failure data suggest that an improved preventive maintenance program with a higher frequency of inspection of the limit and torque switches should increase MOV availability and reliability. The event rate for all failure modes was computed as 4.47 events per 10(exp 8) operating hours by assuming a Poisson distribution of failure over valve operating time. The 5 percent and 95 percent confidence limits based on a chi-squared probability distribution function were computed as 3.36 and 5.83 events per 10(exp 6) operating hours, respectively. The operating performance of these liquid metal MOVs was compared to similar data for MOVs in commercial light water reactors and was found to exhibit similar failure rates.

  11. Space Shuttle Orbiter Atlantis Liquid Oxygen Pre-Valve Detent Roller Cracking Investigation

    NASA Technical Reports Server (NTRS)

    Holleman, Elizabeth; Eddleman, David; Jacobs, Rebecca; Richard, James

    2008-01-01

    During routine inspections of the Space Shuttle s Main Propulsion System Liquid Oxygen (LO2) pre-valve, the mechanism provided to maintain the valve in the open position was found cracked. The mechanism is a Vespel roller held against the valve visor by a stack of Belleville springs. The roller has been found cracked 3 times. All three instances were in the same valve in the same location. There are 6 pre-valves on each orbiter, and only one has exhibited this problem. Every-flight inspections were instituted and the rollers were found to be cracked after only one flight. Engineers at Marshall Space Flight Center, Johnson Space Center, and Kennedy Space Center worked together to determine a solution. There were several possible contributors to the failure: a misaligned visor, an out-of-specification edge with a sharp radius, an out-of-specification tolerance stack up of a Belleville spring stack that caused un-predicted loads on the Vespel SP-21 roller, and a dimple machined into the side of the roller to indicate LO2 compatibility that created a stress riser. The detent assembly was removed and replaced with parts that were on the low side of the tolerance stack up to eliminate the potential for high loads on the detent roller. After one flight, the roller was inspected and showed fewer signs of wear and no cracks.

  12. 40 CFR 264.1061 - Alternative standards for valves in gas/vapor service or in light liquid service: percentage of...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... gas/vapor service or in light liquid service: percentage of valves allowed to leak. 264.1061 Section... Emission Standards for Equipment Leaks § 264.1061 Alternative standards for valves in gas/vapor service or in light liquid service: percentage of valves allowed to leak. (a) An owner or operator subject...

  13. 40 CFR 265.1061 - Alternative standards for valves in gas/vapor service or in light liquid service: percentage of...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... gas/vapor service or in light liquid service: percentage of valves allowed to leak. 265.1061 Section... FACILITIES Air Emission Standards for Equipment Leaks § 265.1061 Alternative standards for valves in gas/vapor service or in light liquid service: percentage of valves allowed to leak. (a) An owner or...

  14. 40 CFR 264.1061 - Alternative standards for valves in gas/vapor service or in light liquid service: percentage of...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... gas/vapor service or in light liquid service: percentage of valves allowed to leak. 264.1061 Section... Emission Standards for Equipment Leaks § 264.1061 Alternative standards for valves in gas/vapor service or in light liquid service: percentage of valves allowed to leak. (a) An owner or operator subject...

  15. 40 CFR 265.1061 - Alternative standards for valves in gas/vapor service or in light liquid service: percentage of...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... gas/vapor service or in light liquid service: percentage of valves allowed to leak. 265.1061 Section... FACILITIES Air Emission Standards for Equipment Leaks § 265.1061 Alternative standards for valves in gas/vapor service or in light liquid service: percentage of valves allowed to leak. (a) An owner or...

  16. 40 CFR 264.1061 - Alternative standards for valves in gas/vapor service or in light liquid service: percentage of...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... gas/vapor service or in light liquid service: percentage of valves allowed to leak. 264.1061 Section... Emission Standards for Equipment Leaks § 264.1061 Alternative standards for valves in gas/vapor service or in light liquid service: percentage of valves allowed to leak. (a) An owner or operator subject...

  17. 40 CFR 264.1061 - Alternative standards for valves in gas/vapor service or in light liquid service: percentage of...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... gas/vapor service or in light liquid service: percentage of valves allowed to leak. 264.1061 Section... Emission Standards for Equipment Leaks § 264.1061 Alternative standards for valves in gas/vapor service or in light liquid service: percentage of valves allowed to leak. (a) An owner or operator subject...

  18. 40 CFR 265.1061 - Alternative standards for valves in gas/vapor service or in light liquid service: percentage of...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... gas/vapor service or in light liquid service: percentage of valves allowed to leak. 265.1061 Section... FACILITIES Air Emission Standards for Equipment Leaks § 265.1061 Alternative standards for valves in gas/vapor service or in light liquid service: percentage of valves allowed to leak. (a) An owner or...

  19. 40 CFR 265.1061 - Alternative standards for valves in gas/vapor service or in light liquid service: percentage of...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... gas/vapor service or in light liquid service: percentage of valves allowed to leak. 265.1061 Section... FACILITIES Air Emission Standards for Equipment Leaks § 265.1061 Alternative standards for valves in gas/vapor service or in light liquid service: percentage of valves allowed to leak. (a) An owner or...

  20. Development of a passive liquid valve (PLV) utilizing a pressure equilibrium phenomenon on the centrifugal microfluidic platform.

    PubMed

    Al-Faqheri, Wisam; Ibrahim, Fatimah; Thio, Tzer Hwai Gilbert; Bahari, Norulain; Arof, Hamzah; Rothan, Hussin A; Yusof, Rohana; Madou, Marc

    2015-02-25

    In this paper, we propose an easy-to-implement passive liquid valve (PLV) for the microfluidic compact-disc (CD). This valve can be implemented by introducing venting chambers to control the air flow of the source and destination chambers. The PLV mechanism is based on equalizing the main forces acting on the microfluidic CD (i.e., the centrifugal and capillary forces) to control the burst frequency of the source chamber liquid. For a better understanding of the physics behind the proposed PLV, an analytical model is described. Moreover, three parameters that control the effectiveness of the proposed valve, i.e., the liquid height, liquid density, and venting chamber position with respect to the CD center, are tested experimentally. To demonstrate the ability of the proposed PLV valve, microfluidic liquid switching and liquid metering are performed. In addition, a Bradford assay is performed to measure the protein concentration and evaluated in comparison to the benchtop procedure. The result shows that the proposed valve can be implemented in any microfluidic process that requires simplicity and accuracy. Moreover, the developed valve increases the flexibility of the centrifugal CD platform for passive control of the liquid flow without the need for an external force or trigger.

  1. Development of a Passive Liquid Valve (PLV) Utilizing a Pressure Equilibrium Phenomenon on the Centrifugal Microfluidic Platform

    PubMed Central

    Al-Faqheri, Wisam; Ibrahim, Fatimah; Thio, Tzer Hwai Gilbert; Bahari, Norulain; Arof, Hamzah; Rothan, Hussin A.; Yusof, Rohana; Madou, Marc

    2015-01-01

    In this paper, we propose an easy-to-implement passive liquid valve (PLV) for the microfluidic compact-disc (CD). This valve can be implemented by introducing venting chambers to control the air flow of the source and destination chambers. The PLV mechanism is based on equalizing the main forces acting on the microfluidic CD (i.e., the centrifugal and capillary forces) to control the burst frequency of the source chamber liquid. For a better understanding of the physics behind the proposed PLV, an analytical model is described. Moreover, three parameters that control the effectiveness of the proposed valve, i.e., the liquid height, liquid density, and venting chamber position with respect to the CD center, are tested experimentally. To demonstrate the ability of the proposed PLV valve, microfluidic liquid switching and liquid metering are performed. In addition, a Bradford assay is performed to measure the protein concentration and evaluated in comparison to the benchtop procedure. The result shows that the proposed valve can be implemented in any microfluidic process that requires simplicity and accuracy. Moreover, the developed valve increases the flexibility of the centrifugal CD platform for passive control of the liquid flow without the need for an external force or trigger. PMID:25723143

  2. Optical logic gates using liquid crystal light valve - Implementation and application example

    NASA Astrophysics Data System (ADS)

    Fatehi, M. T.; Wasmundt, K. C.; Collins, S. A., Jr.

    1981-07-01

    In this paper, a new method of optically implementing digital logic gates capable of performing all logic operations is proposed, and the technique for construction of an array of n-bit parallel adders as a typical application circuit is given. These gates are implemented using a Hughes liquid crystal light valve operated in the parallel off-state configuration. It is found that all possible functions of two binary variables are realizable with these gates, some as bright-true-logic and some as dark-true-logic. Experimental results will be given using the portions of a single liquid crystal light valve demonstrating the feasibility of AND, NOR, XOR, etc. gate arrays. As an example of implementation of combinatorial circuits, a design for an array of binary adders will also be given.

  3. Dynamic gratings recording in liquid crystal light valve with semiconductor substrate

    NASA Astrophysics Data System (ADS)

    Shcherbin, Konstantin; Gvozdovskyy, Igor; Evans, Dean R.

    2016-03-01

    Liquid crystal light valve with GaAs substrate operating in the transmission mode in the infrared is studied. The nonlinear phase shift of the transmitted light wave is measured as a function of applied voltage. The dynamic grating recording is achieved. A fourfold amplification of the weak signal beam is reached. The gain is increased by means of proper tilting of the cell that increases an effective pretilt of the liquid crystal molecules. The amplitude of the refractive index modulation and nonlinear coupling constant are estimated from the experimental results.

  4. Piezo- and solenoid valve-based liquid dispensing for miniaturized assays.

    PubMed

    Niles, Walter D; Coassin, Peter J

    2005-04-01

    Miniaturization of biological assays requires dispensing liquids in the submicroliter range of volumes. Accuracy and reproducibility of dispensing this range depend on both the dispenser and the receptacle in which the assay is constructed. Miniaturization technologies developed by Aurora Discovery, Inc. (San Diego, CA) include high-density multiwell plates for assay samples and reagent storage, as well as piezo-based and solenoid valve-based liquid dispensers. Some basic principles of small-volume dispensing by jetting are described to provide context for dispenser design and function. Performance of the latest instruments incorporating these dispensing devices is presented.

  5. 46 CFR 154.530 - Valves: Cargo tank MARVS 69 kPa gauge (10 psig) or lower.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... DANGEROUS CARGOES SAFETY STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and Equipment Cargo and Process Piping Systems § 154.530 Valves: Cargo tank MARVS 69 kPa gauge (10 psig) or lower. (a) Except those connections for tank safety relief valves and for liquid level gauging...

  6. 46 CFR 154.530 - Valves: Cargo tank MARVS 69 kPa gauge (10 psig) or lower.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... DANGEROUS CARGOES SAFETY STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and Equipment Cargo and Process Piping Systems § 154.530 Valves: Cargo tank MARVS 69 kPa gauge (10 psig) or lower. (a) Except those connections for tank safety relief valves and for liquid level gauging...

  7. Spatiotemporal chaotic localized state in liquid crystal light valve experiments with optical feedback.

    PubMed

    Verschueren, N; Bortolozzo, U; Clerc, M G; Residori, S

    2013-03-08

    The existence, stability properties, and dynamical evolution of localized spatiotemporal chaos are studied. We provide evidence of spatiotemporal chaotic localized structures in a liquid crystal light valve experiment with optical feedback. The observations are supported by numerical simulations of the Lifshitz model describing the system. This model exhibits coexistence between a uniform state and a spatiotemporal chaotic pattern, which emerge as the necessary ingredients to obtain localized spatiotemporal chaos. In addition, we have derived a simplified model that allows us to unveil the front interaction mechanism at the origin of the localized spatiotemporal chaotic structures.

  8. Signal-beam amplification by two-wave mixing in a liquid-crystal light valve.

    PubMed

    Brignon, A; Bongrand, I; Loiseaux, B; Huignard, J P

    1997-12-15

    A new two-wave-mixing interaction with gain through a Bi(12)SiO(20) liquid-crystal light valve is presented. We show that the diffraction of a pump beam in the direction of a weak signal leads to a net amplification of the signal beam, with no need for a phase shift between the interference pattern and the induced index grating. A two-wave-mixing gain of 10 and a 150-ms response time are obtained with a 8.8-microm -thick liquid-crystal layer, a total intensity of the interacting beams of only 200 muW/cm(2), and an ac external voltage of +/-6 V . Image amplification is also demonstrated.

  9. EVALUATION OF SPRING OPERATED RELIEF VALVE MAINTENANCE INTERVALS AND EXTENSION OF MAINTENANCE TIMES USING A WEIBULL ANALYSIS WITH MODIFIED BAYESIAN UPDATING

    SciTech Connect

    Harris, S.; Gross, R.; Mitchell, E.

    2011-01-18

    The Savannah River Site (SRS) spring operated pressure relief valve (SORV) maintenance intervals were evaluated using an approach provided by the American Petroleum Institute (API RP 581) for risk-based inspection technology (RBI). In addition, the impact of extending the inspection schedule was evaluated using Monte Carlo Simulation (MCS). The API RP 581 approach is characterized as a Weibull analysis with modified Bayesian updating provided by SRS SORV proof testing experience. Initial Weibull parameter estimates were updated as per SRS's historical proof test records contained in the Center for Chemical Process Safety (CCPS) Process Equipment Reliability Database (PERD). The API RP 581 methodology was used to estimate the SORV's probability of failing on demand (PFD), and the annual expected risk. The API RP 581 methodology indicates that the current SRS maintenance plan is conservative. Cost savings may be attained in certain mild service applications that present low PFD and overall risk. Current practices are reviewed and recommendations are made for extending inspection intervals. The paper gives an illustration of the inspection costs versus the associated risks by using API RP 581 Risk Based Inspection (RBI) Technology. A cost effective maintenance frequency balancing both financial risk and inspection cost is demonstrated.

  10. Pressure Relief Devices

    NASA Astrophysics Data System (ADS)

    Manha, William D.

    2010-09-01

    Pressure relief devices are used in pressure systems and on pressure vessels to prevent catastrophic rupture or explosion from excessive pressure. Pressure systems and pressure vessels have manufacturers maximum rated operating pressures or maximum design pressures(MDP) for which there are relatively high safety factors and minimum risk of rupture or explosion. Pressure systems and pressure vessels that have a potential to exceed the MDP by being connected to another higher pressure source, a compressor, or heat to water(boiler) are required to have over-pressure protecting devices. Such devices can be relief valves and/or burst discs to safely relieve potentially excessive pressure and prevent unacceptable ruptures and explosions which result in fail-safe pressure systems and pressure vessels. Common aerospace relief valve and burst disc requirements and standards will be presented. This will include the NASA PSRP Interpretation Letter TA-88-074 Fault Tolerance of Systems Using Specially Certified Burst Disks that dictates burst disc requirements for payloads on Shuttle. Two recent undesirable manned space payloads pressure relief devices and practices will be discussed, as well as why these practices should not be continued. One example for discussion is the use of three burst discs that have been placed in series to comply with safety requirements of three controls to prevent a catastrophic hazard of the over-pressurization and rupture of pressure system and/or vessels. The cavities between the burst discs are evacuated and are the reference pressures for activating the two upstream burst discs. If the upstream burst disc leaks into the reference cavity, the reference pressure increases and it can increase the burst disc activating pressure and potentially result in the burst disc assembly being ineffective for over pressure protection. The three burst discs-in-series assembly was found acceptable because the burst discs are designed for minimum risk(DFMR) of

  11. Technical evaluation report TMI action -- NUREG-0737 (II.D.1). Relief and safety valve testing, Watts Bar Nuclear Plant, Units 1 and 2 (Dockets 50-390 and 50-391)

    SciTech Connect

    Fineman, C.P.

    1995-02-01

    In the past, safety and relief valves installed in the primary coolant system of light water reactors have performed improperly. As a result, the authors of NUREG-0578 (TMI-2 Lessons Learned Task Force Status Report and Short-Term Recommendations) and, subsequently, NUREG-0737 (Clarification of TMI Action Plan Requirements) recommended development and completion of programs to do two things. First, they should reevaluate the functional performance capabilities of pressurized water reactor safety, relief, and block valves. Second, they should verify the integrity of the pressurizer safety and relief valve piping systems for normal, transient, and accident conditions. This report documents the review of those programs by Lockheed Idaho Technologies Company. Specifically, this report documents the review of the Watts Bar Nuclear Plant, Units 1 and 2, Applicant response to the requirements of NUREG-0578 and NUREG-0737. This review found the Applicant provided an acceptable response reconfirming they met General Design Criteria 14, 15, and 30 of Appendix A to 10 CFR 50 for the subject equipment. It should also be noted Lockheed Idaho performed this review for both Units 1 and 2. However, the applicability of this review to Unit 2 depends on verifying that the Unit 2 as-built system conforms to the Unit 1 design reviewed in this report.

  12. 40 CFR 264.1058 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... method specified in § 264.1063(b) if evidence of a potential leak is found by visual, audible, olfactory...) Any connector that is inaccessible or is ceramic or ceramic-lined (e.g., porcelain, glass, or glass...

  13. 40 CFR 265.1058 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... within 5 days by the method specified in § 265.1063(b) if evidence of a potential leak is found by visual..., glass, or glass-lined) is exempt from the monitoring requirements of paragraph (a) of this section and...

  14. 40 CFR 264.1058 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... method specified in § 264.1063(b) if evidence of a potential leak is found by visual, audible, olfactory...) Any connector that is inaccessible or is ceramic or ceramic-lined (e.g., porcelain, glass, or glass...

  15. 40 CFR 265.1058 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... within 5 days by the method specified in § 265.1063(b) if evidence of a potential leak is found by visual..., glass, or glass-lined) is exempt from the monitoring requirements of paragraph (a) of this section and...

  16. 40 CFR 264.1058 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... method specified in § 264.1063(b) if evidence of a potential leak is found by visual, audible, olfactory...) Any connector that is inaccessible or is ceramic or ceramic-lined (e.g., porcelain, glass, or glass...

  17. 40 CFR 265.1058 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... within 5 days by the method specified in § 265.1063(b) if evidence of a potential leak is found by visual..., glass, or glass-lined) is exempt from the monitoring requirements of paragraph (a) of this section and...

  18. 40 CFR 264.1058 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... method specified in § 264.1063(b) if evidence of a potential leak is found by visual, audible, olfactory...) Any connector that is inaccessible or is ceramic or ceramic-lined (e.g., porcelain, glass, or glass...

  19. 40 CFR 265.1058 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... within 5 days by the method specified in § 265.1063(b) if evidence of a potential leak is found by visual..., glass, or glass-lined) is exempt from the monitoring requirements of paragraph (a) of this section and...

  20. 40 CFR 264.1058 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... method specified in § 264.1063(b) if evidence of a potential leak is found by visual, audible, olfactory...) Any connector that is inaccessible or is ceramic or ceramic-lined (e.g., porcelain, glass, or glass...

  1. 40 CFR 265.1058 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... within 5 days by the method specified in § 265.1063(b) if evidence of a potential leak is found by visual..., glass, or glass-lined) is exempt from the monitoring requirements of paragraph (a) of this section and...

  2. Probabilistic analysis and operational data in response to NUREG-0737, Item II. K. 3. 2 for Westinghouse NSSS plants. [Modifications to reduce LOCA due to stuck-open power-operated relief valve

    SciTech Connect

    Wood, D.C.; Gottshall, C.L.

    1981-02-01

    This report describes various modifications to Westinghouse plants since TMI and, using probabilistic analysis via event trees, estimates the effect of the post-TMI changes, including an automatic (PORV) (power operated relief valve) isolation concept identified in NUREG-0731 item II.K.3.1. The requested safety valve operational data is included as an appendix. A significant reduction in the frequency of a small break LOCA, due to a stuck open PORV has already been achieved by the modifications made subsequent to TMI. Domestic Westinghouse operating plant data (based on 181 reactor years of operation) has been collected and evaluated. An auto block valve closure system has been evaluated. The analysis is generally applicable to all Westinghouse plants which have incorporated the post-TMI hardware and procedural changes relative to stuck-open PORVs.

  3. Cyanoacrylate medical adhesives--a new era Colgate ORABASE Soothe.N.Seal Liquid Protectant for canker sore relief.

    PubMed

    Narang, U

    2001-01-01

    Cyanoacrylate, a synthetic adhesive, is a fast polymerizable liquid monomer. Serendipity led to the discovery of cyanoacrylate adhesives in 1951. Today, a specific cyanoacrylate monomer, 2-octyl cyanoacrylate, is being used in a topical medical adhesive formulation. The only over-the-counter cyanoacrylate-based product cleared by the Food and Drug Administration is Colgate ORABASE Soothe.N. Seal Liquid Protectant. Upon application, this liquid monomer formulation polymerizes instantly into a thin, flexible polymer film that adheres tenaciously to mucosal tissue. This polymer film creates a mechanical barrier that provides immediate and long-term pain relief of oral ulcerations and irritations, and maintains a natural healing environment for the area to heal.

  4. Comparison of Stress Relief Mechanisms of Metal Films Deposited on Liquid Substrates by Thermal Evaporating and Sputtering

    NASA Astrophysics Data System (ADS)

    Yu, Sen-Jiang; Zhang, Yong-Ju; Chen, Miao-Gen

    Various metal film systems, deposited on liquid (silicone oil) substrates by thermal evaporating and DC-magnetron sputtering methods, have been successfully fabricated and the stress relief mechanisms are systematically studied by analyzing the characteristic surface morphologies. The experiment shows that the evaporating metal films can move on silicone oil surfaces freely due to the nearly zero adhesion of solid-liquid interface, which results in spontaneous formation of ordered surface patterns with a characteristic sandwiched structure driven by the internal stress. For the sputtering metal film system, however, the top surface of silicone oil can be modified to form an elastomeric polymer layer on the liquid substrate during deposition. Subsequent cooling of the system creates a higher compressive stress in the film, which is relieved by buckling of the film to form periodic wavy structures because the adhesion of solid-elastomer interface is quite strong.

  5. 46 CFR 154.802 - Alternate pressure relief settings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Alternate pressure relief settings. 154.802 Section 154... Equipment Cargo Vent Systems § 154.802 Alternate pressure relief settings. Cargo tanks with more than one relief valve setting must have one of the following arrangements: (a) Relief valves that: (1) Are set...

  6. 40 CFR 63.1025 - Valves in gas and vapor service and in light liquid service standards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Valves in gas and vapor service and in light liquid service standards. 63.1025 Section 63.1025 Protection of Environment ENVIRONMENTAL... by the provisions of § 63.1023(b)(6). (b) Leak detection. Unless otherwise specified in § 63.1021(b...

  7. 49 CFR 173.318 - Cryogenic liquids in cargo tanks.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... pressure relief valves only. (ii) Tanks in helium and atmospheric gas (except oxygen) cryogenic liquid service. For a tank used in helium and atmospheric gas (except oxygen) cryogenic liquid service, the tank... Pamphlet S-1.2. (ii) Tanks in helium and atmospheric gas (except oxygen) cryogenic liquid service....

  8. 49 CFR 173.318 - Cryogenic liquids in cargo tanks.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... pressure relief valves only. (ii) Tanks in helium and atmospheric gas (except oxygen) cryogenic liquid service. For a tank used in helium and atmospheric gas (except oxygen) cryogenic liquid service, the tank... Pamphlet S-1.2. (ii) Tanks in helium and atmospheric gas (except oxygen) cryogenic liquid service....

  9. 49 CFR 173.318 - Cryogenic liquids in cargo tanks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... pressure relief valves only. (ii) Tanks in helium and atmospheric gas (except oxygen) cryogenic liquid service. For a tank used in helium and atmospheric gas (except oxygen) cryogenic liquid service, the tank... Pamphlet S-1.2. (ii) Tanks in helium and atmospheric gas (except oxygen) cryogenic liquid service....

  10. 49 CFR 173.318 - Cryogenic liquids in cargo tanks.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... pressure relief valves only. (ii) Tanks in helium and atmospheric gas (except oxygen) cryogenic liquid service. For a tank used in helium and atmospheric gas (except oxygen) cryogenic liquid service, the tank... Pamphlet S-1.2. (ii) Tanks in helium and atmospheric gas (except oxygen) cryogenic liquid service....

  11. Optical flip-flops and sequential logic circuits using a liquid crystal light valve

    NASA Technical Reports Server (NTRS)

    Fatehi, M. T.; Collins, S. A., Jr.; Wasmundt, K. C.

    1984-01-01

    This paper is concerned with the application of optics to digital computing. A Hughes liquid crystal light valve is used as an active optical element where a weak light beam can control a strong light beam with either a positive or negative gain characteristic. With this device as the central element the ability to produce bistable states from which different types of flip-flop can be implemented is demonstrated. In this paper, some general comments are first presented on digital computing as applied to optics. This is followed by a discussion of optical implementation of various types of flip-flop. These flip-flops are then used in the design of optical equivalents to a few simple sequential circuits such as shift registers and accumulators. As a typical sequential machine, a schematic layout for an optical binary temporal integrator is presented. Finally, a suggested experimental configuration for an optical master-slave flip-flop array is given.

  12. Real time optical edge enhancement using a Hughes liquid crystal light valve

    NASA Technical Reports Server (NTRS)

    Chao, Tien-Hsin

    1989-01-01

    The discovery of an edge enhancement effect in using a Hughes CdS liquid crystal light valve (LCLV) is reported. An edge-enhanced version of the input writing image can be directly obtained by operating the LCLV at a lower bias frequency and bias voltage. Experimental conditions in which this edge enhancement effect can be optimized are described. Experimental results show that the SNR of the readout image using this technique is superior to that obtained using high-pass filtering. The repeatability of this effect is confirmed by obtaining an edge enhancement result using two different Hughes LCLVs. The applicability of this effect to improve discrimination capability in optical pattern recognition is addressed. The results show that the Hughes LCLV can be used in both continuous tone and edge-enhancing modes by simply adjusting its bias conditions.

  13. Real time optical edge enhancement using a Hughes liquid crystal light valve

    NASA Technical Reports Server (NTRS)

    Chao, Tien-Hsin

    1989-01-01

    The discovery of an edge enhancement effect in using a Hughes CdS liquid crystal light valve (LCLV) is reported. An edge-enhanced version of the input writing image can be directly obtained by operating the LCLV at a lower bias frequency and bias voltage. Experimental conditions in which this edge enhancement effect can be optimized are described. Experimental results show that the SNR of the readout image using this technique is superior to that obtained using high-pass filtering. The repeatability of this effect is confirmed by obtaining an edge enhancement result using two different Hughes LCLVs. The applicability of this effect to improve discrimination capability in optical pattern recognition is addressed. The results show that the Hughes LCLV can be used in both continuous tone and edge-enhancing modes by simply adjusting its bias conditions.

  14. Optical flip-flops and sequential logic circuits using a liquid crystal light valve

    NASA Technical Reports Server (NTRS)

    Fatehi, M. T.; Collins, S. A., Jr.; Wasmundt, K. C.

    1984-01-01

    This paper is concerned with the application of optics to digital computing. A Hughes liquid crystal light valve is used as an active optical element where a weak light beam can control a strong light beam with either a positive or negative gain characteristic. With this device as the central element the ability to produce bistable states from which different types of flip-flop can be implemented is demonstrated. In this paper, some general comments are first presented on digital computing as applied to optics. This is followed by a discussion of optical implementation of various types of flip-flop. These flip-flops are then used in the design of optical equivalents to a few simple sequential circuits such as shift registers and accumulators. As a typical sequential machine, a schematic layout for an optical binary temporal integrator is presented. Finally, a suggested experimental configuration for an optical master-slave flip-flop array is given.

  15. Microfluidic sieve valves

    DOEpatents

    Quake, Stephen R; Marcus, Joshua S; Hansen, Carl L

    2015-01-13

    Sieve valves for use in microfluidic device are provided. The valves are useful for impeding the flow of particles, such as chromatography beads or cells, in a microfluidic channel while allowing liquid solution to pass through the valve. The valves find particular use in making microfluidic chromatography modules.

  16. 40 CFR 265.1061 - Alternative standards for valves in gas/vapor service or in light liquid service: percentage of...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... gas/vapor service or in light liquid service: percentage of valves allowed to leak. 265.1061 Section 265.1061 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED... FACILITIES Air Emission Standards for Equipment Leaks § 265.1061 Alternative standards for valves in gas...

  17. 40 CFR 264.1061 - Alternative standards for valves in gas/vapor service or in light liquid service: percentage of...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... gas/vapor service or in light liquid service: percentage of valves allowed to leak. 264.1061 Section 264.1061 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED... Emission Standards for Equipment Leaks § 264.1061 Alternative standards for valves in gas/vapor service or...

  18. Variable reluctance proximity sensors for cryogenic valve position indication

    NASA Technical Reports Server (NTRS)

    Cloyd, R. A.

    1982-01-01

    A test was conducted to determine the performance of a variable reluctance proximity sensor system when installed in a space shuttle external tank vent/relief valve. The sensors were used as position indicators. The valve and sensors were cycled through a series of thermal transients; while the valve was being opened and closed pneumatically, the sensor's performance was being monitored. During these thermal transients, the vent valve was cooled ten times by liquid nitrogen and two times by liquid hydrogen. It was concluded that the sensors were acceptable replacements for the existing mechanical switches. However, the sensors need a mechanical override for the target similar to what is presently used with the mechanical switches. This override could insure contact between sensor and target and eliminate any problems of actuation gap growth caused by thermal gradients.

  19. DOT regulations, safety relief valves

    SciTech Connect

    Emerson, G.B.

    1981-01-01

    This review of overpressure protective devices is based on the ASME guide for gas transmission and distribution piping systems of 1980. Analysis of overpressure protection methods in the industry has been increasing since 1970 to insure that provisions of Part. 192, Title 49, Code of Federal Regulations, ''Transportation of natural and other gas by pipelines: minimum federal safety standards'', are being complied with or plans are being made to comply. The basic premise for protection against accidental overpressure is explained, i.e., the maximum allowable operating pressure in a gas system could be exceeded either at a compressor station or in a pipeline downstream of a pressure control devices; overpressure protection devices must be used on all of these installations with the exception of centrifugal compresssors. Four groups of locations where overpressure protection is needed are identified: compressor stations; gas holders, pipelines, and all facilities that might at times be bottle-tight; high pressure distribution systems; and low pressure distribution systems.

  20. Nonlinear optics and liquid crystal light valve for laser beam control

    NASA Astrophysics Data System (ADS)

    Huignard, Jean Pierre; Brignon, Arnaud; Steinhausser, Bastien

    2008-11-01

    The recent advances in solid state laser technology now permit to achieve high energy and efficiency sources for a wide range of applications extending from laser physics to material processing, biophotonics, remote sensing and coherent lidar systems. In particular the progress of fibre laser exploiting the double clading diode pumping structure are impressive: they are compact and emit single mode beams. However optical damage and nonlinear effects limit the output peak power emitted by a single mode fiber laser. Also limitations arise in bulk laser materials due to the thermal loading which induces strong wavefront distortions on the beams. We develop in this paper original concepts adapted to power-energy scaling of bulk or fibre lasers. The final objective is to emit high brightness and high energy beams whose quality is close to the diffraction limit. For this purpose we present new technics to be inspired from from Fourier optics and allowing the wavefront processing either through nonlinear interactions or with adaptive optical components such as electro optic phase modulators or liquid crystal light valves.

  1. Temperature-Operated Valve

    NASA Technical Reports Server (NTRS)

    Morrison, Andrew D.

    1994-01-01

    Bimetallic valve stem positions orifice at end of inner pipe orifice so liquid flows to outlet when temperature lies within small range of preset value. If liquid too cold or too hot, orifices misaligned and liquid returned to source. Such as in shower, valve prevents outflow of dangerously hot or uncomfortably cold water.

  2. Temperature-Operated Valve

    NASA Technical Reports Server (NTRS)

    Morrison, Andrew D.

    1994-01-01

    Bimetallic valve stem positions orifice at end of inner pipe orifice so liquid flows to outlet when temperature lies within small range of preset value. If liquid too cold or too hot, orifices misaligned and liquid returned to source. Such as in shower, valve prevents outflow of dangerously hot or uncomfortably cold water.

  3. 40 CFR 265.1062 - Alternative standards for valves in gas/vapor service or in light liquid service: skip period...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... gas/vapor service or in light liquid service: skip period leak detection and repair. 265.1062 Section... FACILITIES Air Emission Standards for Equipment Leaks § 265.1062 Alternative standards for valves in gas/vapor service or in light liquid service: skip period leak detection and repair. (a) An owner...

  4. 40 CFR 264.1062 - Alternative standards for valves in gas/vapor service or in light liquid service: skip period...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... gas/vapor service or in light liquid service: skip period leak detection and repair. 264.1062 Section... Emission Standards for Equipment Leaks § 264.1062 Alternative standards for valves in gas/vapor service or in light liquid service: skip period leak detection and repair. (a) An owner or operator subject...

  5. 40 CFR 264.1062 - Alternative standards for valves in gas/vapor service or in light liquid service: skip period...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... gas/vapor service or in light liquid service: skip period leak detection and repair. 264.1062 Section... Emission Standards for Equipment Leaks § 264.1062 Alternative standards for valves in gas/vapor service or in light liquid service: skip period leak detection and repair. (a) An owner or operator subject...

  6. 40 CFR 264.1062 - Alternative standards for valves in gas/vapor service or in light liquid service: skip period...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... gas/vapor service or in light liquid service: skip period leak detection and repair. 264.1062 Section... Emission Standards for Equipment Leaks § 264.1062 Alternative standards for valves in gas/vapor service or in light liquid service: skip period leak detection and repair. (a) An owner or operator subject...

  7. 40 CFR 265.1062 - Alternative standards for valves in gas/vapor service or in light liquid service: skip period...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... gas/vapor service or in light liquid service: skip period leak detection and repair. 265.1062 Section... FACILITIES Air Emission Standards for Equipment Leaks § 265.1062 Alternative standards for valves in gas/vapor service or in light liquid service: skip period leak detection and repair. (a) An owner...

  8. 40 CFR 264.1062 - Alternative standards for valves in gas/vapor service or in light liquid service: skip period...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... gas/vapor service or in light liquid service: skip period leak detection and repair. 264.1062 Section... Emission Standards for Equipment Leaks § 264.1062 Alternative standards for valves in gas/vapor service or in light liquid service: skip period leak detection and repair. (a) An owner or operator subject...

  9. 40 CFR 265.1062 - Alternative standards for valves in gas/vapor service or in light liquid service: skip period...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... gas/vapor service or in light liquid service: skip period leak detection and repair. 265.1062 Section... FACILITIES Air Emission Standards for Equipment Leaks § 265.1062 Alternative standards for valves in gas/vapor service or in light liquid service: skip period leak detection and repair. (a) An owner...

  10. 40 CFR 265.1062 - Alternative standards for valves in gas/vapor service or in light liquid service: skip period...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... gas/vapor service or in light liquid service: skip period leak detection and repair. 265.1062 Section... FACILITIES Air Emission Standards for Equipment Leaks § 265.1062 Alternative standards for valves in gas/vapor service or in light liquid service: skip period leak detection and repair. (a) An owner...

  11. Relief Sculpture

    ERIC Educational Resources Information Center

    Lawrence, Trudy

    2005-01-01

    Relief sculpture is an art form that is midway between painting and sculpture in the round. It is a process in which the subject stands out or projects a surface from the background. The surface has several levels. It can be low relief or high relief (deep or almost round) or anywhere in between. The most common example of low relief is a coin…

  12. 40 CFR 63.1010 - Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief devices in...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... evidence of a potential leak to the atmosphere is found by visual, audible, olfactory, or any other..., or other indications of a leak to the atmosphere have been eliminated; that no bubbles are observed...

  13. 40 CFR 63.1029 - Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief devices in...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... applicable, § 63.1023(c), if evidence of a potential leak to the atmosphere is found by visual, audible...), repaired shall mean that the visual, audible, olfactory, or other indications of a leak to the atmosphere...

  14. 40 CFR 63.1029 - Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief devices in...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... standards. 63.1029 Section 63.1029 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES... have been eliminated; that no bubbles are observed at potential leak sites during a leak check using...

  15. 40 CFR 63.1010 - Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief devices in...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... standards. 63.1010 Section 63.1010 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES..., or other indications of a leak to the atmosphere have been eliminated; that no bubbles are observed...

  16. 40 CFR 63.1029 - Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief devices in...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... standards. 63.1029 Section 63.1029 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES... have been eliminated; that no bubbles are observed at potential leak sites during a leak check using...

  17. 40 CFR 63.1029 - Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief devices in...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... standards. 63.1029 Section 63.1029 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES... have been eliminated; that no bubbles are observed at potential leak sites during a leak check using...

  18. 40 CFR 63.1010 - Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief devices in...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... standards. 63.1010 Section 63.1010 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES..., or other indications of a leak to the atmosphere have been eliminated; that no bubbles are observed...

  19. 40 CFR 63.1010 - Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief devices in...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... standards. 63.1010 Section 63.1010 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES..., or other indications of a leak to the atmosphere have been eliminated; that no bubbles are observed...

  20. Overflow control valve

    DOEpatents

    Hundal, Rolv; Kessinger, Boyd A.; Parlak, Edward A.

    1984-07-24

    An overflow control valve for use in a liquid sodium coolant pump tank which valve can be extended to create a seal with the pump tank wall or retracted to break the seal thereby accommodating valve removal. An actuating shaft which controls valve disc position also has cams which bear on roller surfaces to force retraction of a sliding cylinder against spring tension to retract the cylinder from sealing contact with the pump tank.

  1. Design of ITER Relief Lines

    NASA Astrophysics Data System (ADS)

    Shah, N.; Choukekar, K.; Jadon, M.; Sarkar, B.; Joshi, B.; Kanzaria, H.; Gehani, V.; Vyas, H.; Pandya, U.; Panjwani, R.; Badgujar, S.; Monneret, E.

    2017-02-01

    The ITER Cryogenic system is one of the most complex cryogenic systems in the world. It includes roughly 5 km of cryogenic transfer line (cryolines) having large number of layout singularities in terms of bends at odd angles and branches. The relief lines are particularly important cryolines as they collect the helium from outlet of all process safety valves of the cryogenic clients and transfers it back to cryoplant. The total length of ITER relief lines is around 1.6 km with process pipe size varying from DN 50 to DN 200. While some part of relief lines carries warm helium for the recovery system, most part of the relief line is vacuum jacketed cryoline which carries cold helium from the clients. The final detailed design of relief lines has been completed. The paper describes the major input data and constraints for design of relief lines, design steps, flexibility and structural analysis approach and major design outcome.

  2. 40 CFR 65.106 - Standards: Valves in gas/vapor service and in light liquid service.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... determining monitoring frequency for each process unit or valve subgroup subject to annual or biennial (once... valves. Any equipment located at a plant site with fewer than 250 valves in regulated material service is...

  3. 40 CFR 65.106 - Standards: Valves in gas/vapor service and in light liquid service.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... determining monitoring frequency for each process unit or valve subgroup subject to annual or biennial (once... valves. Any equipment located at a plant site with fewer than 250 valves in regulated material service is...

  4. Fast-responding liquid crystal light-valve technology for color-sequential display applications

    NASA Astrophysics Data System (ADS)

    Janssen, Peter J.; Konovalov, Victor A.; Muravski, Anatoli A.; Yakovenko, Sergei Y.

    1996-04-01

    A color sequential projection system has some distinct advantages over conventional systems which make it uniquely suitable for consumer TV as well as high performance professional applications such as computer monitors and electronic cinema. A fast responding light-valve is, clearly, essential for a good performing system. Response speed of transmissive LC lightvalves has been marginal thus far for good color rendition. Recently, Sevchenko Institute has made some very fast reflective LC cells which were evaluated at Philips Labs. These devices showed sub millisecond-large signal-response times, even at room temperature, and produced good color in a projector emulation testbed. In our presentation we describe our highly efficient color sequential projector and demonstrate its operation on video tape. Next we discuss light-valve requirements and reflective light-valve test results.

  5. Evaluation of Cylinder, Solenoid Valve and Servovalve Contaminant Sensitivity

    DTIC Science & Technology

    1984-02-01

    observed on poppets in relief valves and balls A in check valves as well as servovalve spool orifices. In Ref. [9], it was stated that performance...in these fields of applications. In fluid power systems, particle impingement erosion can be observed on poppets in relief valves and balls in check... poppet system inside, normally, spool-housing type valves do not have critical failure or degradation due to qD wear. With spool-housing type valves , wear

  6. 46 CFR 64.67 - Shutoff valve.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Shutoff valve. 64.67 Section 64.67 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MARINE PORTABLE TANKS AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.67 Shutoff valve. A shutoff...

  7. 46 CFR 64.67 - Shutoff valve.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Shutoff valve. 64.67 Section 64.67 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MARINE PORTABLE TANKS AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.67 Shutoff valve. A shutoff...

  8. 46 CFR 64.67 - Shutoff valve.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Shutoff valve. 64.67 Section 64.67 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MARINE PORTABLE TANKS AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.67 Shutoff valve. A shutoff...

  9. 46 CFR 64.67 - Shutoff valve.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Shutoff valve. 64.67 Section 64.67 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MARINE PORTABLE TANKS AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.67 Shutoff valve. A shutoff...

  10. 46 CFR 64.67 - Shutoff valve.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Shutoff valve. 64.67 Section 64.67 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MARINE PORTABLE TANKS AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.67 Shutoff valve. A shutoff...

  11. 19 CFR 172.1 - Notice of liquidated damages or penalty incurred and right to petition for relief.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... penalty incurred. When there is a failure to meet the conditions of any bond posted with Customs or when a... liability at the same time. (b) Notice of right to petition for relief. The notice will inform the...

  12. 40 CFR 264.1062 - Alternative standards for valves in gas/vapor service or in light liquid service: skip period...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... gas/vapor service or in light liquid service: skip period leak detection and repair. 264.1062 Section 264.1062 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED... Emission Standards for Equipment Leaks § 264.1062 Alternative standards for valves in gas/vapor service or...

  13. 40 CFR 265.1062 - Alternative standards for valves in gas/vapor service or in light liquid service: skip period...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... gas/vapor service or in light liquid service: skip period leak detection and repair. 265.1062 Section 265.1062 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED... FACILITIES Air Emission Standards for Equipment Leaks § 265.1062 Alternative standards for valves in gas...

  14. [Comparative study on the immunogenicity of human homologous cardiac valve and great artery homograft cryopreserved with liquid nitrogen].

    PubMed

    Yu, Jian-Hua; Guo, Hong-Wei; Liu, Mei-Ming; Zhang, Gong; Wu, Shu-Ming

    2009-08-18

    To study the differences on the immunogenicity of the leaflets, arterial wall and myocardium of conduit valved homograft (CVH) cryopreserved with liquid nitrogen. Mono-cell suspension of leaflets cells and arterial cells of CVH were respectively co-cultured with human lymphatic cells whose blood groups were the same with that of CVH donors. Expressive levels of CD25 and HLA-DR of these lymphatic cells were detected by flow cytometry in the different cultural duration and compared with that of lymph cells alone cultured (comparative group). The immunogenicity of CVH artery walls was more severe than that of CVH leaflets, and expressive level of whose CD25 and HLA-DR was higher. The immunogenicity of CVH myocardium was not studied because the myocardial cell suspension were not be acquired in this study. It is proved that in vitro experimental study that the immunogenicity of arterial walls of cryopreserved CVH is more severe than that of leaflets.

  15. Real-time optical correlator using computer-generated holographic filter on a liquid crystal light valve

    NASA Technical Reports Server (NTRS)

    Chao, Tien-Hsin; Yu, Jeffrey

    1990-01-01

    Limitations associated with the binary phase-only filter often used in optical correlators are presently circumvented in the writing of complex-valued data on a gray-scale spatial light modulator through the use of a computer-generated hologram (CGH) algorithm. The CGH encodes complex-valued data into nonnegative real CGH data in such a way that it may be encoded in any of the available gray-scale spatial light modulators. A CdS liquid-crystal light valve is used for the complex-valued CGH encoding; computer simulations and experimental results are compared, and the use of such a CGH filter as the synapse hologram in a holographic optical neural net is discussed.

  16. Real-time optical correlator using computer-generated holographic filter on a liquid crystal light valve

    NASA Technical Reports Server (NTRS)

    Chao, Tien-Hsin; Yu, Jeffrey

    1990-01-01

    Limitations associated with the binary phase-only filter often used in optical correlators are presently circumvented in the writing of complex-valued data on a gray-scale spatial light modulator through the use of a computer-generated hologram (CGH) algorithm. The CGH encodes complex-valued data into nonnegative real CGH data in such a way that it may be encoded in any of the available gray-scale spatial light modulators. A CdS liquid-crystal light valve is used for the complex-valued CGH encoding; computer simulations and experimental results are compared, and the use of such a CGH filter as the synapse hologram in a holographic optical neural net is discussed.

  17. Main Oxidizer Valve Design

    NASA Technical Reports Server (NTRS)

    Addona, Brad; Eddleman, David

    2015-01-01

    A developmental Main Oxidizer Valve (MOV) was designed by NASA-MSFC using additive manufacturing processes. The MOV is a pneumatically actuated poppet valve to control the flow of liquid oxygen to an engine's injector. A compression spring is used to return the valve to the closed state when pneumatic pressure is removed from the valve. The valve internal parts are cylindrical in shape, which lends itself to traditional lathe and milling operations. However, the valve body represents a complicated shape and contains the majority of the mass of the valve. Additive manufacturing techniques were used to produce a part that optimized mass and allowed for design features not practical with traditional machining processes.

  18. 40 CFR 63.1025 - Valves in gas and vapor service and in light liquid service standards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... or biennial (once every 2 years) monitoring frequencies, the percent leaking valves shall be the... in § 63.1022(c)(4). (3) Fewer than 250 valves. Any equipment located at a plant site with fewer than...

  19. 49 CFR 179.500-16 - Tests of pressure relief devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Tests of pressure relief devices. 179.500-16... 107A) § 179.500-16 Tests of pressure relief devices. (a) Pressure relief valves shall be tested by air or gas before being put into service. Valve shall open at pressure not exceeding the marked...

  20. 49 CFR 179.400-19 - Valves and gages.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...-19 Valves and gages. (a) Valves. Manually operated shut-off valves and control valves must be provided wherever needed for control of vapor phase pressure, vapor phase venting, liquid transfer and... satisfactory properties at the lading temperature. (1) Liquid control valves must be of extended stem design...

  1. 49 CFR 179.400-20 - Pressure relief devices.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR TANK CARS... safety appliances. Vent or weep holes in pressure relief devices are prohibited. All main pressure relief... lines between the final valve and end closure. (b) Materials. Materials used in pressure relief devices...

  2. Safety valve

    DOEpatents

    Bergman, Ulf C.

    1984-01-01

    The safety valve contains a resilient gland to be held between a valve seat and a valve member and is secured to the valve member by a sleeve surrounding the end of the valve member adjacent to the valve seat. The sleeve is movable relative to the valve member through a limited axial distance and a gap exists between said valve member and said sleeve.

  3. Solid handling valve

    DOEpatents

    Williams, William R.

    1979-01-01

    The present invention is directed to a solids handling valve for use in combination with lock hoppers utilized for conveying pulverized coal to a coal gasifier. The valve comprises a fluid-actuated flow control piston disposed within a housing and provided with a tapered primary seal having a recessed seat on the housing and a radially expandable fluid-actuated secondary seal. The valve seals are highly resistive to corrosion, erosion and abrasion by the solids, liquids, and gases associated with the gasification process so as to minimize valve failure.

  4. Increasing the Useful Life of Quench Reliefs with Inconel Bellows

    SciTech Connect

    Soyars, W. M.

    1999-01-01

    Reliable quench relief valves are an important part of superconducting magnet systems. Fermilab developed bellows-actuated cryogenic quench reliefs which have been in use since the early l 980's. The original design uses a stainless steel bellows. A high frequency, low amplitude vibration during relieving events has resulted in fatigue failures in the original design. To take advantage of the improved resistance to fatigue of Inconel, a nickel-chromium alloy, reliefs using Inconel 625 bellows were made. Design, development, and testing of the new version reliefs will be discussed. Tests show that relief valve lifetimes using Inconel bellows are more than five times greater than when using the original stainless steel bellows. Inconel bellows show great promise in increasing the lifetime of quench relief valves, and thus the reliability of accelerator cryogenic systems.

  5. 49 CFR 179.500-16 - Tests of pressure relief devices.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 107A) § 179.500-16 Tests of pressure relief devices. (a) Pressure relief valves shall be tested by air... devices that incorporate a rupture disc, samples of the discs used shall burst at a pressure not...

  6. 49 CFR 179.500-16 - Tests of pressure relief devices.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 107A) § 179.500-16 Tests of pressure relief devices. (a) Pressure relief valves shall be tested by air... devices that incorporate a rupture disc, samples of the discs used shall burst at a pressure not...

  7. 49 CFR 179.500-16 - Tests of pressure relief devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 107A) § 179.500-16 Tests of pressure relief devices. (a) Pressure relief valves shall be tested by air... devices that incorporate a rupture disc, samples of the discs used shall burst at a pressure not...

  8. Three-Dimensional Large Screen Display Using Polymer-Dispersed Liquid-Crystal Light Valves and a Schlieren Optical System: Proposal and Basic Experiments

    NASA Astrophysics Data System (ADS)

    Takizawa, Kuniharu

    A novel three-dimensional (3-D) projection display used with polarized eyeglasses is proposed. It consists of polymer-dispersed liquid crystal-light valves that modulate the illuminated light based on light scattering, a polarization beam splitter, and a Schlieren projection system. The features of the proposed display include a 3-D image display with a single projector, half size and half power consumption compared with a conventional 3-D projector with polarized glasses. Measured electro-optic characteristics of a polymer-dispersed liquid-crystal cell inserted between crossed polarizers suggests that the proposed display achieves small cross talk and high-extinction ratio.

  9. Multiple-Star System Adaptive Vortex Coronagraphy Using a Liquid Crystal Light Valve

    NASA Astrophysics Data System (ADS)

    Aleksanyan, Artur; Kravets, Nina; Brasselet, Etienne

    2017-05-01

    We propose the development of a high-contrast imaging technique enabling the simultaneous and selective nulling of several light sources. This is done by realizing a reconfigurable multiple-vortex phase mask made of a liquid crystal thin film on which local topological features can be addressed electro-optically. The method is illustrated by reporting on a triple-star optical vortex coronagraphy laboratory demonstration, which can be easily extended to higher multiplicity. These results allow considering the direct observation and analysis of worlds with multiple suns and more complex extrasolar planetary systems.

  10. 46 CFR 64.79 - Inspection of pressure and vacuum relief device.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Inspection of pressure and vacuum relief device. 64.79... pressure and vacuum relief device. (a) The inspection of the pressure and vacuum relief device required in... of the accuracy of the pressure setting. (b) If the pressure and vacuum relief valve passes...

  11. 46 CFR 64.79 - Inspection of pressure and vacuum relief device.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Inspection of pressure and vacuum relief device. 64.79... pressure and vacuum relief device. (a) The inspection of the pressure and vacuum relief device required in... of the accuracy of the pressure setting. (b) If the pressure and vacuum relief valve passes...

  12. 46 CFR 64.79 - Inspection of pressure and vacuum relief device.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Inspection of pressure and vacuum relief device. 64.79... pressure and vacuum relief device. (a) The inspection of the pressure and vacuum relief device required in... of the accuracy of the pressure setting. (b) If the pressure and vacuum relief valve passes...

  13. 46 CFR 64.79 - Inspection of pressure and vacuum relief device.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Inspection of pressure and vacuum relief device. 64.79... pressure and vacuum relief device. (a) The inspection of the pressure and vacuum relief device required in... of the accuracy of the pressure setting. (b) If the pressure and vacuum relief valve passes...

  14. 46 CFR 64.79 - Inspection of pressure and vacuum relief device.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Inspection of pressure and vacuum relief device. 64.79... pressure and vacuum relief device. (a) The inspection of the pressure and vacuum relief device required in... of the accuracy of the pressure setting. (b) If the pressure and vacuum relief valve passes...

  15. Drumlin relief

    NASA Astrophysics Data System (ADS)

    Spagnolo, Matteo; Clark, Chris D.; Hughes, Anna L. C.

    2012-06-01

    Drumlin relief is a key parameter for testing predictions of models of drumlin formation. Although this metric is commonly described in textbooks as being of the order of a few tens of metres, our critical review of the literature suggests an average value of about 13 m, but with much uncertainty. Here we investigate a large sample of drumlins (25,848) mapped from a high resolution digital terrain model of Britain, which allowed the identification of extremely shallow drumlins. Results indicate that most drumlins have a relief between 0.5 and 40 m (with a surprisingly low average value of only 7.1 m) a mode of 3.5-4 m, and with 41% of all drumlins characterized by a relief < 5 m. Drumlin relief is found to never exceed 7% of the width and is positively correlated with this parameter, possibly indicating that drumlins need a large base to stand against the flow of the ice. Drumlin relief is also positively correlated with the length, which shows that drumlins do not grow in length by redistributing sediments from their summits to their downflow (lee) end, as previously hypothesised.

  16. A novel dual-valve sequential injection manifold (DV-SIA) for automated liquid-liquid extraction. Application for the determination of picric acid.

    PubMed

    Skrlíková, Jana; Andruch, Vasil; Sklenárová, Hana; Chocholous, Petr; Solich, Petr; Balogh, Ioseph S

    2010-05-07

    A novel dual-valve sequential injection system (DV-SIA) for online liquid-liquid extraction which resolves the main problems of LLE utilization in SIA has been designed. The main idea behind this new design was to construct an SIA system by connecting two independent units, one for aqueous-organic mixture flow and the second specifically for organic phase flow. As a result, the DV-SIA manifold consists of an Extraction unit and a Detection unit. Processing a mixture of aqueous-organic phase in the Extraction unit and a separated organic phase in the Detection unit solves the problems associated with the change of phases having different affinities to the walls of the Teflon tubing used in the SI-system. The developed manifold is a simple, user-friendly and universal system built entirely from commercially available components. The system can be used for a variety of samples and organic solvents and is simple enough to be easily handled by operators less familiar with flow systems. The efficiency of the DV-SIA system is demonstrated by the extraction of picric acid in the form of an ion associate with 2-[2-(4-methoxy-phenylamino)-vinyl]-1,3,3-trimethyl-3H-indolium reagent, with subsequent spectrophotometric detection. The suggested DV-SIA concept can be expected to stimulate new experiments in analytical laboratories and can be applied to the elaboration of procedures for the determination of other compounds extractable by organic solvents. It could thus form a basis for the design of simple, single-purpose commercial instruments used in LLE procedures.

  17. 49 CFR 179.400-19 - Valves and gages.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... the lading temperature. (1) Liquid control valves must be of extended stem design. (2) Packing, if... effectively seal the valve stem without causing difficulty of operation. (3) Each control valve and shut-off...

  18. 40 CFR 63.168 - Standards: Valves in gas/vapor service and in light liquid service.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... each group of existing process units at existing sources subject to the provisions of subpart F or I of... valves for leaks at the intervals specified below: (1) At process units with 2 percent or greater leaking... subpart and monitor quarterly. (2) At process units with less than 2 percent leaking valves, the owner or...

  19. 40 CFR 63.1006 - Valves in gas and vapor service and in light liquid service standards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... paragraph (b) of this section, and the owner or operator shall monitor the valve according to the written...), or § 63.1016, or in paragraph (e) of this section, or the referencing subpart, the owner or operator shall monitor all valves at the intervals specified in paragraphs (b)(3) through (b)(6) of this section...

  20. Effect of pressure pulses at the interface valve on the stability of second dimension columns in online comprehensive two-dimensional liquid chromatography.

    PubMed

    Talus, Eric S; Witt, Klaus E; Stoll, Dwight R

    2015-01-23

    Users of online comprehensive two-dimensional liquid chromatography (LCxLC) frequently acknowledge that the mechanical instability of HPLC columns installed in these systems, particularly in the second dimension, is a significant impediment to its use. Such instability is not surprising given the strenuous operating environment to which these columns are subjected, including the large number (thousands per day) of fast and large pressure pulses resulting from interface valve switches (on the timescale of tens of milliseconds) associated with very fast second dimension separations. There appear to be no published reports of systematic studies of the relationship between second dimension column lifetime and any of these variables. In this study we focused on the relationship between the lifetimes of commercially available columns and the pressure pulses observed at the inlet of the second dimension column that occur during the switching of the valve that interfaces the two dimensions of a LCxLC system. We find that the magnitude of the pressure drop at the inlet of the second dimension column during the valve switch, which may vary between 10 and 95% of the column inlet pressure, is dependent on valve switching speed and design, and has a dramatic impact on column lifetime. In the worst case, columns fail within the first few hours of use in an LCxLC system. In the best case, using a valve that exhibits much smaller pressure pulses, the same columns exhibit much improved lifetimes and have been used continuously under LCxLC conditions for several days with no degradation in performance. This result represents a first step in understanding the factors that affect second dimension column lifetime, and will significantly improve the usability of the LCxLC technique in general.

  1. Plug valve

    DOEpatents

    Wordin, John J.

    1989-01-01

    An improved plug valve wherein a novel shape for the valve plug and valve chamber provide mating surfaces for improved wear characteristics. The novel shape of the valve plug is a frustum of a body of revolution of a curved known as a tractrix, a solid shape otherwise known as a peudosphere.

  2. Studies for the requirements of automatic and remotely controlled shutoff valves on hazardous liquids and natural gas pipelines with respect to public and environmental safety

    SciTech Connect

    Oland, C. Barry; Rose, Simon D.; Grant, Herb L.; Lower, Mark D.; Spann, Mark A.; Kirkpatrick, John R.; Sulfredge, C. David

    2012-12-01

    This study assesses the effectiveness of block valve closure swiftness in mitigating the consequences of natural gas and hazardous liquid pipeline releases on public and environmental safety. It also evaluates the technical, operational, and economic feasibility and potential cost benefits of installing automatic shutoff valves (ASVs) and remote control valves (RCVs) in newly constructed and fully replaced transmission lines. Risk analyses of hypothetical pipeline release scenarios are used as the basis for assessing: (1) fire damage to buildings and property in Class 1, Class 2, Class 3, and Class 4 high consequence areas (HCAs) caused by natural gas pipeline releases and subsequent ignition of the released natural gas; (2) fire damage to buildings and property in HCAs designated as high population areas and other populated areas caused by hazardous liquid pipeline releases and subsequent ignition of the released propane; and (3) socioeconomic and environmental damage in HCAs caused by hazardous liquid pipeline releases of crude oil. These risk analyses use engineering principles and fire science practices to characterize thermal radiation effects on buildings and humans and to quantify the total damage cost of socioeconomic and environmental impacts. The risk analysis approach used for natural gas pipelines is consistent with risk assessment standards developed by industry and incorporated into Federal pipeline safety regulations. Feasibility evaluations for the hypothetical pipeline release scenarios considered in this study show that installation of ASVs and RCVs in newly constructed and fully replaced natural gas and hazardous liquid pipelines is technically, operationally, and economically feasible with a positive cost benefit. However, these results may not apply to all newly constructed and fully replaced pipelines because site-specific parameters that influence risk analyses and feasibility evaluations often vary significantly from one pipeline segment to

  3. 49 CFR 179.300-17 - Tests of pressure relief devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Tests of pressure relief devices. 179.300-17... pressure relief devices. (a) Each valve shall be tested by air or gas before being put into service. The valve shall open and be vapor-tight at the pressure prescribed in § 179.301. (b) Rupture disks of...

  4. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT THE PROTECTOSEAL COMPANY PIN-TECH BUBBLE TIGHT < 500 PPM RELIEF VENT

    EPA Science Inventory

    The Environmental Technology Verification report discusses the technology and performance of a pressure relief valve for protection of storage tanks that operate at pressures of 15 psig or less. Four Pin-Tech Bubble Tight <500 ppm Relief Vent valves manufactured by the Protectose...

  5. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT THE PROTECTOSEAL COMPANY PIN-TECH BUBBLE TIGHT < 500 PPM RELIEF VENT

    EPA Science Inventory

    The Environmental Technology Verification report discusses the technology and performance of a pressure relief valve for protection of storage tanks that operate at pressures of 15 psig or less. Four Pin-Tech Bubble Tight <500 ppm Relief Vent valves manufactured by the Protectose...

  6. 49 CFR 179.15 - Pressure relief devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... disc is used in combination with a reclosing pressure relief valve, the rupture disc must be designed... be installed to detect any accumulation of pressure between the rupture disc and the reclosing... relief device must incorporate a rupture disc designed to burst at a pressure equal to the greater of 100...

  7. 46 CFR 56.50-20 - Pressure relief piping.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Pressure relief piping. 56.50-20 Section 56.50-20... APPURTENANCES Design Requirements Pertaining to Specific Systems § 56.50-20 Pressure relief piping. (a) General... pressure-relieving safety devices shall be designed to facilitate drainage. (c) Stop valves. Stop...

  8. 46 CFR 56.50-20 - Pressure relief piping.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Pressure relief piping. 56.50-20 Section 56.50-20... APPURTENANCES Design Requirements Pertaining to Specific Systems § 56.50-20 Pressure relief piping. (a) General... pressure-relieving safety devices shall be designed to facilitate drainage. (c) Stop valves. Stop...

  9. 46 CFR 56.50-20 - Pressure relief piping.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Pressure relief piping. 56.50-20 Section 56.50-20... APPURTENANCES Design Requirements Pertaining to Specific Systems § 56.50-20 Pressure relief piping. (a) General... pressure-relieving safety devices shall be designed to facilitate drainage. (c) Stop valves. Stop...

  10. 46 CFR 56.50-20 - Pressure relief piping.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Pressure relief piping. 56.50-20 Section 56.50-20... APPURTENANCES Design Requirements Pertaining to Specific Systems § 56.50-20 Pressure relief piping. (a) General... pressure-relieving safety devices shall be designed to facilitate drainage. (c) Stop valves. Stop...

  11. 46 CFR 56.50-20 - Pressure relief piping.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Pressure relief piping. 56.50-20 Section 56.50-20... APPURTENANCES Design Requirements Pertaining to Specific Systems § 56.50-20 Pressure relief piping. (a) General... pressure-relieving safety devices shall be designed to facilitate drainage. (c) Stop valves. Stop...

  12. Check valve

    DOEpatents

    Upton, H.A.; Garcia, P.

    1999-08-24

    A check valve for use in a GDCS of a nuclear reactor and having a motor driven disk including a rotatable armature for rotating the check valve disk over its entire range of motion is described. In one embodiment, the check valve includes a valve body having a coolant flow channel extending therethrough. The coolant flow channel includes an inlet end and an outlet end. A valve body seat is located on an inner surface of the valve body. The check valve further includes a disk assembly, sometimes referred to as the motor driven disc, having a counterweight and a disk shaped valve. The disk valve includes a disk base having a seat for seating with the valve body seat. The disk assembly further includes a first hinge pin member which extends at least partially through the disk assembly and is engaged to the disk. The disk valve is rotatable relative to the first hinge pin member. The check valve also includes a motor having a stator frame with a stator bore therein. An armature is rotatably positioned within the stator bore and the armature is coupled to the disk valve to cause the disk valve to rotate about its full range of motion. 5 figs.

  13. Check valve

    DOEpatents

    Upton, Hubert Allen; Garcia, Pablo

    1999-08-24

    A check valve for use in a GDCS of a nuclear reactor and having a motor driven disk including a rotatable armature for rotating the check valve disk over its entire range of motion is described. In one embodiment, the check valve includes a valve body having a coolant flow channel extending therethrough. The coolant flow channel includes an inlet end and an outlet end. A valve body seat is located on an inner surface of the valve body. The check valve further includes a disk assembly, sometimes referred to as the motor driven disc, having a counterweight and a disk shaped valve. The disk valve includes a disk base having a seat for seating with the valve body seat. The disk assembly further includes a first hinge pin member which extends at least partially through the disk assembly and is engaged to the disk. The disk valve is rotatable relative to the first hinge pin member. The check valve also includes a motor having a stator frame with a stator bore therein. An armature is rotatably positioned within the stator bore and the armature is coupled to the disk valve to cause the disk valve to rotate about its full range of motion.

  14. 46 CFR 154.801 - Pressure relief systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Pressure relief systems. 154.801 Section 154.801... Vent Systems § 154.801 Pressure relief systems. (a) Each cargo tank that has a volume of 20m3 (706 ft.3) or less must have at least one pressure relief valve. (b) Each cargo tank that has a volume of...

  15. 46 CFR 154.801 - Pressure relief systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Pressure relief systems. 154.801 Section 154.801... Vent Systems § 154.801 Pressure relief systems. (a) Each cargo tank that has a volume of 20m3 (706 ft.3) or less must have at least one pressure relief valve. (b) Each cargo tank that has a volume of...

  16. 46 CFR 154.801 - Pressure relief systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Pressure relief systems. 154.801 Section 154.801... Vent Systems § 154.801 Pressure relief systems. (a) Each cargo tank that has a volume of 20m3 (706 ft.3) or less must have at least one pressure relief valve. (b) Each cargo tank that has a volume of...

  17. 46 CFR 64.47 - Type of relief devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Type of relief devices. 64.47 Section 64.47 Shipping... CARGO HANDLING SYSTEMS Standards for an MPT § 64.47 Type of relief devices. (a) An MPT with an internal capacity of more than 550 U.S. gallons must have one or more spring loaded relief valves. In addition, a...

  18. Improved Photosensor for Light Valves

    NASA Technical Reports Server (NTRS)

    Koda, N. J.

    1983-01-01

    Processing changes improve performance of liquid-crystal light valve for displaying projection TV images. New approach monitors performance of finished light valves for given changes in CdS process and experimentally to optimize process for good sensitivity and low negative memory.

  19. Design criteria monograph for valve components

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Monograph treats valve design technology problems as they were solved in successful development of flightweight operational valves for liquid rocket systems. General practices for cleaning and contamination prevention are summarized. Balance of information is arranged by topic, since detail design requirements apply to most types of valves.

  20. Fast valve

    SciTech Connect

    Van Dyke, William J.

    1992-01-01

    A fast valve is disclosed that can close on the order of 7 milliseconds. It is closed by the force of a compressed air spring with the moving parts of the valve designed to be of very light weight and the valve gate being of wedge shaped with O-ring sealed faces to provide sealing contact without metal to metal contact. The combination of the O-ring seal and an air cushion create a soft final movement of the valve closure to prevent the fast air acting valve from having a harsh closing.

  1. Fast valve

    DOEpatents

    Van Dyke, W.J.

    1992-04-07

    A fast valve is disclosed that can close on the order of 7 milliseconds. It is closed by the force of a compressed air spring with the moving parts of the valve designed to be of very light weight and the valve gate being of wedge shaped with O-ring sealed faces to provide sealing contact without metal to metal contact. The combination of the O-ring seal and an air cushion create a soft final movement of the valve closure to prevent the fast air acting valve from having a harsh closing. 4 figs.

  2. Analysis of Complex Valve and Feed Systems

    NASA Technical Reports Server (NTRS)

    Ahuja, Vineet; Hosangadi, Ashvin; Shipman, Jeremy; Cavallo, Peter; Dash, Sanford

    2007-01-01

    A numerical framework for analysis of complex valve systems supports testing of propulsive systems by simulating key valve and control system components in the test loop. In particular, it is designed to enhance the analysis capability in terms of identifying system transients and quantifying the valve response to these transients. This system has analysis capability for simulating valve motion in complex systems operating in diverse flow regimes ranging from compressible gases to cryogenic liquids. A key feature is the hybrid, unstructured framework with sub-models for grid movement and phase change including cryogenic cavitations. The multi-element unstructured framework offers improved predictions of valve performance characteristics under steady conditions for structurally complex valves such as pressure regulator valve. Unsteady simulations of valve motion using this computational approach have been carried out for various valves in operation at Stennis Space Center such as the split-body valve and the 10-in. (approx.25.4-cm) LOX (liquid oxygen) valve and the 4-in. (approx.10 cm) Y-pattern valve (liquid nitrogen). Such simulations make use of variable grid topologies, thereby permitting solution accuracy and resolving important flow physics in the seat region of the moving valve. An advantage to this software includes possible reduction in testing costs incurred due to disruptions relating to unexpected flow transients or functioning of valve/flow control systems. Prediction of the flow anomalies leading to system vibrations, flow resonance, and valve stall can help in valve scheduling and significantly reduce the need for activation tests. This framework has been evaluated for its ability to predict performance metrics like flow coefficient for cavitating venturis and valve coefficient curves, and could be a valuable tool in predicting and understanding anomalous behavior of system components at rocket propulsion testing and design sites.

  3. Computations Of Flows In Flapper Valves

    NASA Technical Reports Server (NTRS)

    Kandula, Mastanaiah; Pearce, Dan

    1993-01-01

    Three reports describe computational studies of flows of liquid oxygen and liquid hydrogen in flapper valves located at quick-disconnect interface between main propellant feedlines of Space Shuttle orbiter and Space Shuttle external tank.

  4. Computations Of Flows In Flapper Valves

    NASA Technical Reports Server (NTRS)

    Kandula, Mastanaiah; Pearce, Dan

    1993-01-01

    Three reports describe computational studies of flows of liquid oxygen and liquid hydrogen in flapper valves located at quick-disconnect interface between main propellant feedlines of Space Shuttle orbiter and Space Shuttle external tank.

  5. Depressurization valve

    DOEpatents

    Skoda, G.I.

    1989-03-28

    A depressurization valve for use in relieving completely the pressure in a simplified boiling water reactor is disclosed. The normally closed and sealed valve is provided with a valve body defining a conduit from an outlet of a manifold from the reactor through a valve seat. A closing valve disk is configured for fitting to the valve seat to normally close the valve. The seat below the disk is provided with a radially extending annulus extending a short distance into the aperture defined by the seat. The disk is correspondingly provided with a longitudinally extending annulus that extends downwardly through the aperture defined by the seat towards the high pressure side of the valve body. A ring shaped membrane is endlessly welded to the seat annulus and to the disk annulus. The membrane is conformed over the confronted surface of the seat and disk in a C-sectioned configuration to seal the depressurization valve against the possibility of weeping. The disk is held to the closed position by an elongate stem extending away from the high pressure side of the valve body. The stem has a flange configured integrally to the stem for bias by two springs. The first spring acts from a portion of the housing overlying the disk on the stem flange adjacent the disk. This spring urges the stem and attached disk away from the seat and thus will cause the valve to open at any pressure. A second spring-preferably of the Belleville variety-acts on a latch plate surrounding and freely moving relative to the end of the stem. This second spring overcomes the bias of the first spring and any pressure acting upon the disk. This Belleville spring maintains through its spring force the valve in the closed position. At the same time, the latch plate with its freedom of movement relative to the stem allows the stem to thermally expand during valve temperature excursion.

  6. EVALUATION OF A MULTIFUNCTIONAL VALVE ASSEMBLY IN A DIRECT EXPANSION REFRIGERATION SYSTEM REPORT

    EPA Science Inventory

    The report describes the performance, including energy consumption, of a refrigeration system incorporating a multifunctional valve (MXV assembly). The MXV assembly (consisting of additional liquid line, an XTC valve, and a larger thermostatic expansion valve) was installed on al...

  7. EVALUATION OF A MULTIFUNCTIONAL VALVE ASSEMBLY IN A DIRECT EXPANSION REFRIGERATION SYSTEM REPORT

    EPA Science Inventory

    The report describes the performance, including energy consumption, of a refrigeration system incorporating a multifunctional valve (MXV assembly). The MXV assembly (consisting of additional liquid line, an XTC valve, and a larger thermostatic expansion valve) was installed on al...

  8. Problem: Heart Valve Stenosis

    MedlinePlus

    ... valve . Learn about the different types of stenosis: Aortic stenosis Tricuspid stenosis Pulmonary stenosis Mitral stenosis Outlook for ... Disease "Innocent" Heart Murmur Problem: Valve Stenosis - Problem: Aortic Valve Stenosis - Problem: Mitral Valve Stenosis - Problem: Tricuspid Valve Stenosis - ...

  9. Additively Manufactured Main Fuel Valve Housing

    NASA Technical Reports Server (NTRS)

    Eddleman, David; Richard, Jim

    2015-01-01

    Selective Laser Melting (SLM) was utilized to fabricate a liquid hydrogen valve housing typical of those found in rocket engines and main propulsion systems. The SLM process allowed for a valve geometry that would be difficult, if not impossible to fabricate by traditional means. Several valve bodies were built by different SLM suppliers and assembled with valve internals. The assemblies were then tested with liquid nitrogen and operated as desired. One unit was also burst tested and sectioned for materials analysis. The design, test results, and planned testing are presented herein.

  10. Bipropellant shut-off valve

    NASA Technical Reports Server (NTRS)

    Smith, J. V.

    1971-01-01

    An advanced design of an all metal, fast response, bipropellant, shut-off valve for use on long duration space missions is reported. The valve provides the flow control capability for a 1,000 lb thrust, bipropellant engine using oxygen difluoride and diborane as propellants. The shutoff seal selection is a soft-on-hard metal concept. The soft seal is a spherical shell that seats against a hard conical seat. Beryllium copper and beryllium nickel seals were selected to seal against an electrolyzed Inconel 718 seat. Poppet shaft sealing is achieved by use of hydroformed, Inconel 718 bellows. Two valve assemblies were fabricated and subjected to a series of tests including leak, response time, flow capacity, dry cycles, water cycles, liquid nitrogen cycles, liquid fluorine cycles, and lead-lag operation cycles. These tests demonstrated the ability of the valve to meet design goals.

  11. Septoplasty for left ventricular outflow obstruction without aortic valve replacement: a new technique.

    PubMed

    Cooley, D A; Garrett, J R

    1986-10-01

    A new technique is described for relief of diffuse obstruction in the left ventricular outflow tract without aortic valve replacement. Left ventricular septoplasty was performed, preserving the aortic valve. The supra-valve stenosis was repaired using a Y-shaped extension of the aortotomy proximally and a pantaloon-shaped patch of woven Dacron fabric. A 10-year-old girl with "tunnel" or diffuse stenosis obtained striking relief of left ventricular hypertension by this technique.

  12. Depressurization valve

    DOEpatents

    Skoda, George I.

    1989-01-01

    A depressurization valve for use in relieving completely the pressure in a simplified boiling water reactor is disclosed. The normally closed and sealed valve is provided with a valve body defining a conduit from an outlet of a manifold from the reactor through a valve seat. A closing valve disk is configured for fitting to the valve seat to normally close the valve. The seat below the disk is provided with a radially extending annulus extending a short distance into the aperture defined by the seat. The disk is correspondingly provided with a longitudinally extending annulus that extends downwardly through the aperture defined by the seat towards the high pressure side of the valve body. A ring shaped membrane is endlessly welded to the seat annulus and to the disk annulus. The membrane is conformed over the confronted surface of the seat and disk in a C-sectioned configuration to seal the depressurization valve against the possibility of weeping. The disk is held to the closed position by an elongate stem extending away from the high pressure side of the valve body. The stem has a flange configured integrally to the stem for bias by two springs. The first spring acts from a portion of the housing overlying the disk on the stem flange adjacent the disk. This spring urges the stem and attached disk away from the seat and thus will cause the valve to open at any pressure. A second spring--preferably of the Belleville variety--acts on a latch plate surrounding and freely moving relative to the end of the stem. This second spring overcomes the bias of the first spring and any pressure acting upon the disk. This Belleville spring maintains through its spring force the valve in the closed position. At the same time, the latch plate with its freedom of movement relative to the stem allows the stem to thermally expand during valve temperature excursion. The latch plate in surrounding the stem is limited in its outward movement by a boss attached to the stem at the end of

  13. 46 CFR 153.368 - Pressure-vacuum valves.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Pressure-vacuum valves. 153.368 Section 153.368 Shipping... Systems § 153.368 Pressure-vacuum valves. (a) The pressure side of a required pressure-vacuum relief valve must begin to open only at a pressure exceeding 3.5 kPa gauge (approx. 0.5 psig). (b) A...

  14. 46 CFR 153.368 - Pressure-vacuum valves.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Pressure-vacuum valves. 153.368 Section 153.368 Shipping... Systems § 153.368 Pressure-vacuum valves. (a) The pressure side of a required pressure-vacuum relief valve must begin to open only at a pressure exceeding 3.5 kPa gauge (approx. 0.5 psig). (b) A...

  15. 46 CFR 153.368 - Pressure-vacuum valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Pressure-vacuum valves. 153.368 Section 153.368 Shipping... Systems § 153.368 Pressure-vacuum valves. (a) The pressure side of a required pressure-vacuum relief valve must begin to open only at a pressure exceeding 3.5 kPa gauge (approx. 0.5 psig). (b) A...

  16. 46 CFR 153.368 - Pressure-vacuum valves.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Pressure-vacuum valves. 153.368 Section 153.368 Shipping... Systems § 153.368 Pressure-vacuum valves. (a) The pressure side of a required pressure-vacuum relief valve must begin to open only at a pressure exceeding 3.5 kPa gauge (approx. 0.5 psig). (b) A...

  17. 46 CFR 153.368 - Pressure-vacuum valves.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Pressure-vacuum valves. 153.368 Section 153.368 Shipping... Systems § 153.368 Pressure-vacuum valves. (a) The pressure side of a required pressure-vacuum relief valve must begin to open only at a pressure exceeding 3.5 kPa gauge (approx. 0.5 psig). (b) A...

  18. Nuclear radiation actuated valve

    DOEpatents

    Christiansen, David W.; Schively, Dixon P.

    1985-01-01

    A nuclear radiation actuated valve for a nuclear reactor. The valve has a valve first part (such as a valve rod with piston) and a valve second part (such as a valve tube surrounding the valve rod, with the valve tube having side slots surrounding the piston). Both valve parts have known nuclear radiation swelling characteristics. The valve's first part is positioned to receive nuclear radiation from the nuclear reactor's fuel region. The valve's second part is positioned so that its nuclear radiation induced swelling is different from that of the valve's first part. The valve's second part also is positioned so that the valve's first and second parts create a valve orifice which changes in size due to the different nuclear radiation caused swelling of the valve's first part compared to the valve's second part. The valve may be used in a nuclear reactor's core coolant system.

  19. A throat-bypass stability-bleed system using relief valves to increase the transient stability of a mixed-compression inlet. [YF-12 aircraft inlet tests in the Lewis 10 by 10 ft supersonic wind tunnel

    NASA Technical Reports Server (NTRS)

    Neiner, G. H.; Dustin, M. O.; Cole, G. L.

    1979-01-01

    A stability-bleed system was installed in a YF-12 flight inlet that was subjected to internal and external airflow disturbances in the NASA Lewis 10 by 10 foot supersonic wind tunnel. The purpose of the system is to allow higher inlet performance while maintaining a substantial tolerance (without unstart) to internal and external disturbances. At Mach numbers of 2.47 and 2.76, the inlet tolerance to decreases in diffuser-exit corrected airflow was increased by approximately 10 percent of the operating-point airflow. The stability-bleed system complemented the terminal-shock-control system of the inlet and did not show interaction problems. For disturbances which caused a combined decrease in Mach number and increase in angle of attack, the system with valves operative kept the inlet started 4 to 28 times longer than with the valves inoperative. Hence, the stability system provides additional time for the inlet control system to react and prevent unstart. This was observed for initial Mach numbers of 2.55 and 2.68. For slow increase in angle of attack at Mach 2.47 and 2.76, the system kept the inlet started beyond the steady-state unstart angle. However, the maximum transient angles of attack without unstart could not be determined because wind-tunnel mechanical-stop limits for angle of attack were reached.

  20. Simple Check Valves for Microfluidic Devices

    NASA Technical Reports Server (NTRS)

    Willis, Peter A.; Greer, Harold F.; Smith, J. Anthony

    2010-01-01

    A simple design concept for check valves has been adopted for microfluidic devices that consist mostly of (1) deformable fluorocarbon polymer membranes sandwiched between (2) borosilicate float glass wafers into which channels, valve seats, and holes have been etched. The first microfluidic devices in which these check valves are intended to be used are micro-capillary electrophoresis (microCE) devices undergoing development for use on Mars in detecting compounds indicative of life. In this application, it will be necessary to store some liquid samples in reservoirs in the devices for subsequent laboratory analysis, and check valves are needed to prevent cross-contamination of the samples. The simple check-valve design concept is also applicable to other microfluidic devices and to fluidic devices in general. These check valves are simplified microscopic versions of conventional rubber- flap check valves that are parts of numerous industrial and consumer products. These check valves are fabricated, not as separate components, but as integral parts of microfluidic devices. A check valve according to this concept consists of suitably shaped portions of a deformable membrane and the two glass wafers between which the membrane is sandwiched (see figure). The valve flap is formed by making an approximately semicircular cut in the membrane. The flap is centered over a hole in the lower glass wafer, through which hole the liquid in question is intended to flow upward into a wider hole, channel, or reservoir in the upper glass wafer. The radius of the cut exceeds the radius of the hole by an amount large enough to prevent settling of the flap into the hole. As in a conventional rubber-flap check valve, back pressure in the liquid pushes the flap against the valve seat (in this case, the valve seat is the adjacent surface of the lower glass wafer), thereby forming a seal that prevents backflow.

  1. Bistable (latching) solenoid actuated propellant isolation valve

    NASA Technical Reports Server (NTRS)

    Wichmann, H.; Deboi, H. H.

    1979-01-01

    The design, fabrication, assembly and test of a development configuration bistable (latching) solenoid actuated propellant isolation valve suitable for the control hydrazine and liquid fluorine to an 800 pound thrust rocket engine is described. The valve features a balanced poppet, utilizing metal bellows, a hard poppet/seat interface and a flexure support system for the internal moving components. This support system eliminates sliding surfaces, thereby rendering the valve free of self generated particles.

  2. Self-Rupturing Hermetic Valve

    NASA Technical Reports Server (NTRS)

    Tucker, Curtis E., Jr.; Sherrit, Stewart

    2011-01-01

    For commercial, military, and aerospace applications, low-cost, small, reliable, and lightweight gas and liquid hermetically sealed valves with post initiation on/off capability are highly desirable for pressurized systems. Applications include remote fire suppression, single-use system-pressurization systems, spacecraft propellant systems, and in situ instruments. Current pyrotechnic- activated rupture disk hermetic valves were designed for physically larger systems and are heavy and integrate poorly with portable equipment, aircraft, and small spacecraft and instrument systems. Additionally, current pyrotechnically activated systems impart high g-force shock loads to surrounding components and structures, which increase the risk of damage and can require additional mitigation. The disclosed mechanism addresses the need for producing a hermetically sealed micro-isolation valve for low and high pressure for commercial, aerospace, and spacecraft applications. High-precision electrical discharge machining (EDM) parts allow for the machining of mated parts with gaps less than a thousandth of an inch. These high-precision parts are used to support against pressure and extrusion, a thin hermetically welded diaphragm. This diaphragm ruptures from a pressure differential when the support is removed and/or when the plunger is forced against the diaphragm. With the addition of conventional seals to the plunger and a two-way actuator, a derivative of this design would allow nonhermetic use as an on/off or metering valve after the initial rupturing of the hermetic sealing disk. In addition, in a single-use hermetically sealed isolation valve, the valve can be activated without the use of potential leak-inducing valve body penetrations. One implementation of this technology is a high-pressure, high-flow-rate rupture valve that is self-rupturing, which is advantageous for high-pressure applications such as gas isolation valves. Once initiated, this technology is self

  3. Smart actuators: Valve Health Monitor (VHM) system

    NASA Astrophysics Data System (ADS)

    Perotti, José; Lucena, Angel; Burns, Bradley

    2006-05-01

    The health of electromechanical systems (actuators) and specifically of solenoid valves is a primary concern at Kennedy Space Center (KSC). These systems control the storage and transfer of such commodities as liquid hydrogen. The potential for the failure of electromechanical systems to delay a scheduled launch or to cause personnel injury requires continual maintenance and testing of the systems to ensure their readiness. Monitoring devices need to be incorporated into these systems to verify the health and performance of the valves during real operating conditions. It is very advantageous to detect degradation and/or potential problems before they happen. This feature will not only provide safer operation but save the cost of unnecessary maintenance and inspections. Solenoid valve status indicators are often based upon microswitches that work by physically contacting a valve's poppet assembly. All of the physical contact and movement tends to be very unreliable and is subject to wear and tear of the assemblies, friction, breakage of the switch, and even leakage of the fluid (gas or liquid) in the valve. The NASA Instrumentation Branch, together with its contractor, ASRC Aerospace, has developed a solenoid valve smart current signature sensor that monitors valves in a noninvasive mode. The smart system monitors specific electrical parameters of the solenoid valves and detects and predicts the performance and health of the device. The information obtained from the electrical signatures of these valves points to not only electrical components failures in the valves but also mechanical failures and/or degradations.

  4. TWO-WAY FREEZE VALVE

    DOEpatents

    Lantz, K.D.; Clark, P.M.

    1960-01-01

    A valve for closing off the flow of radioactive and corrosive gases and liquids or mixtures thereof and forming a leak tight barrier is described. This valve has no mechanical moving parts which would require design to close tolerances and retention of the usual seal tighthess. Instead, there is provided a cavity in which a fusible metal is contained. Heating and cooling are provided to exercise control over the state of the metal. Baffle chambers are utilized to separate the molten fusible metal from the gas or liquid which is being passed through and return the molten metal to its cavity.

  5. Aortic Valve Regurgitation

    MedlinePlus

    ... valve. Also, a narrowing of the aortic valve (aortic stenosis) can be associated with leaking. High blood pressure (hypertension). High blood pressure may stretch the root of the aorta where the aortic valve sits. The valve flaps ( ...

  6. Aortic Valve Stenosis

    MedlinePlus

    ... pulmonary valve and aortic valve. Each valve has flaps (cusps or leaflets) that open and close once ... valve consists of three tightly fitting, triangular-shaped flaps of tissue called cusps. Some children are born ...

  7. 49 CFR 195.116 - Valves.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Design Requirements § 195.116 Valves. Each valve installed in a pipeline system must comply with...

  8. 49 CFR 195.116 - Valves.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Design Requirements § 195.116 Valves. Each valve installed in a pipeline system must comply with...

  9. 49 CFR 179.300-17 - Tests of pressure relief devices.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... CARS Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A and 110AW) § 179.300-17 Tests of pressure relief devices. (a) Each valve shall be tested by air or gas before being put into service. The... Cars (IBR, see § 171.7 of this subchapter). (c) For pressure relief devices of the fusible plug type,...

  10. 49 CFR 179.300-17 - Tests of pressure relief devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... FOR TANK CARS Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A and 110AW) § 179.300-17 Tests of pressure relief devices. (a) Each valve shall be tested by air or gas before being put into... Specifications for Tank Cars (IBR, see § 171.7 of this subchapter). (c) For pressure relief devices of...

  11. 49 CFR 179.300-17 - Tests of pressure relief devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... CARS Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A and 110AW) § 179.300-17 Tests of pressure relief devices. (a) Each valve shall be tested by air or gas before being put into service. The... Cars (IBR, see § 171.7 of this subchapter). (c) For pressure relief devices of the fusible plug type,...

  12. 49 CFR 179.300-17 - Tests of pressure relief devices.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... CARS Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A and 110AW) § 179.300-17 Tests of pressure relief devices. (a) Each valve shall be tested by air or gas before being put into service. The... Cars (IBR, see § 171.7 of this subchapter). (c) For pressure relief devices of the fusible plug type,...

  13. Reduced Order Modeling of SLS Liquid Hydrogen Pre-Valve Flow Guide to Enable Rapid Transient Analysis

    NASA Technical Reports Server (NTRS)

    Brown, Andrew M.; Mulder, Andrew

    2017-01-01

    NASA is developing a new launch vehicle, called the Space Launch System (SLS), which is intended on taking humans out of low earth orbit to destinations including the moon, asteroids, and Mars. The propulsion system for the core stage of this vehicle includes four RS-25 Liquid Hydrogen/Oxygen rocket engines. These engines are upgraded versions of the Space Shuttle Main Engines (SSME); the upgrades include higher power levels and affordability enhancements. As with any new vehicle, the Main Propulsion System (MPS), which include the feedlines and ancillary hardware connecting the engines to the fuel and oxidizer tanks, had to be redesigned (figure 1 - export clearance in progress), as the previous MPS for the SSME's was inherently part of the Space Shuttle System, which had a completely different overall configuration.

  14. EC Hidraulic Drive Cylinder Relief Vlave Test

    SciTech Connect

    Wu, J.; /Fermilab

    1991-04-03

    This engineering note documents the testing of the set pressure of the EC hydraulic drive cylinder relief valve. The purpose of the relief valve is to provide a safety measure in the event that oil becomes trapped in the rod side of the cylinder and pressure is applied to the cap side. The note includes an explanation of the procedure used and a summary of the result of the testing done on February 14, 1991 by Gary Trotter. The result was that the cylinder relief valve relieved at the correct set pressure of 10,500 psig. The basic concern is for the protection of the cylinder. The pump is capable of providing up to 10,500 psi of pressure to either side of the cylinder. The cylinder is rated for 10,500 psi. Under normal operating conditions, the valves would be open, and the pumping pressure would automatically flow oil into one side, and remove oil from the other side. If, however, the valve for the other side was closed, so that oil could not be removed, then the pressure would build in that side. If the rod side is pressurized to the maximum pump pressure of 10,500 psi, the cross sectional area ratio of 2.29 results in a pressure of approximately 4600 psi in the cap side, which is well under the rated pressure. If, however, the cap side is pressurized to 10,500 psi, the cross sectional area would produce a pressure of approximately 24,000 psi in the rod side, which could damage the cylinder. Therefore, the pressure on the rod side must be limited to the rated pressure of 10,500 psi. In reality, the maximum operating force on the piston would be under 11,000 Ibs., which would result in the maximum cylinder pressure being under 8000 psi to the rod side, and under 3500 psi to the cap side. Therefore, the relief is only needed as a safety precaution in the case that oil becomes trapped.

  15. 46 CFR 154.546 - Excess flow valve: Closing flow.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Excess flow valve: Closing flow. 154.546 Section 154.546... and Process Piping Systems § 154.546 Excess flow valve: Closing flow. (a) The rated closing flow of vapor or liquid cargo for an excess flow valve must be specially approved by the Commandant (CG-522)....

  16. Wear resistant valve

    NASA Technical Reports Server (NTRS)

    Perkins, Gerald S. (Inventor)

    1980-01-01

    A valve which is resistant to wear caused by particles trapped between the valve seat and the valve member or poppet when the valve closes, including an outlet for directing washing fluid at the valve seat and/or sealing face of the poppet and means for supplying pressured fluid to the outlet at the time when the valve is closing.

  17. A calcified polymeric valve for valve-in-valve applications.

    PubMed

    Falahatpisheh, Ahmad; Morisawa, Daisuke; Toosky, Taraz T; Kheradvar, Arash

    2017-01-04

    The prevalence of aortic valve stenosis (AS) is increasing in the aging society. More recently, novel treatments and devices for AS, especially transcatheter aortic valve replacement (TAVR) have significantly changed the therapeutic approach to this disease. Research and development related to TAVR require testing these devices in the calcified heart valves that closely mimic a native calcific valve. However, no animal model of AS has yet been available. Alternatively, animals with normal aortic valve that are currently used for TAVR experiments do not closely replicate the aortic valve pathology required for proper testing of these devices. To solve this limitation, for the first time, we developed a novel polymeric valve whose leaflets possess calcium hydroxyapatite inclusions immersed in them. This study reports the characteristics and feasibility of these valves. Two types of the polymeric valve, i.e., moderate and severe calcified AS models were developed and tested by deploying a transcatheter valve in those and measuring the related hemodynamics. The valves were tested in a heart flow simulator, and were studied using echocardiography. Our results showed high echogenicity of the polymeric valve, that was correlated to the severity of the calcification. Aortic valve area of the polymeric valves was measured, and the severity of stenosis was defined according to the clinical guidelines. Accordingly, we showed that these novel polymeric valves closely mimic AS, and can be a desired cost-saving solution for testing the performance of the transcatheter aortic valve systems in vitro.

  18. 49 CFR 236.383 - Valve locks, valves, and valve magnets.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Valve locks, valves, and valve magnets. 236.383... Inspection and Tests § 236.383 Valve locks, valves, and valve magnets. Valve locks on valves of the non-cut-off type shall be tested at least once every three months, and valves and valve magnets shall...

  19. 49 CFR 236.383 - Valve locks, valves, and valve magnets.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Valve locks, valves, and valve magnets. 236.383... Inspection and Tests § 236.383 Valve locks, valves, and valve magnets. Valve locks on valves of the non-cut-off type shall be tested at least once every three months, and valves and valve magnets shall...

  20. 49 CFR 236.383 - Valve locks, valves, and valve magnets.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Valve locks, valves, and valve magnets. 236.383... Inspection and Tests § 236.383 Valve locks, valves, and valve magnets. Valve locks on valves of the non-cut-off type shall be tested at least once every three months, and valves and valve magnets shall...

  1. 49 CFR 236.383 - Valve locks, valves, and valve magnets.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Valve locks, valves, and valve magnets. 236.383... Inspection and Tests § 236.383 Valve locks, valves, and valve magnets. Valve locks on valves of the non-cut-off type shall be tested at least once every three months, and valves and valve magnets shall...

  2. 49 CFR 236.383 - Valve locks, valves, and valve magnets.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Valve locks, valves, and valve magnets. 236.383... Inspection and Tests § 236.383 Valve locks, valves, and valve magnets. Valve locks on valves of the non-cut-off type shall be tested at least once every three months, and valves and valve magnets shall...

  3. Development and validation of a high-performance liquid chromatography method for the determination of cold relief ingredients in chewing gum.

    PubMed

    Gasco-Lopez, A I; Izquierdo-Hornillos, R; Jiminez, A

    1997-07-18

    An isocratic high-performance liquid chromatography (HPLC) method for the simultaneous determination of the active compounds paracetamol, pseudoephedrine and chlorpheniramine in chewing gum samples has been developed and validated. The method required a simple liquid-liquid extraction using n-hexane and a mixture of water-acetonitrile prior to HPLC analysis. The chromatographic separation was achieved with an aqueous solution containing hexylamine (pH 3)-acetonitrile as the mobile phase, a Spherisorb C18 column and UV detection at 220 nm. As an application, the proposed method has been used to evaluate the release into saliva of these compounds from samples under a controlled human chewing process.

  4. Electrodynamic actuators for rocket engine valves

    NASA Technical Reports Server (NTRS)

    Fiet, O.; Doshi, D.

    1972-01-01

    Actuators, employed in acoustic loudspeakers, operate liquid rocket engine valves by replacing light paper cones with flexible metal diaphragms. Comparative analysis indicates better response time than solenoid actuators, and improved service life and reliability.

  5. Piezoelectric valve

    SciTech Connect

    Petrenko, Serhiy Fedorovich

    2013-01-15

    A motorized valve has a housing having an inlet and an outlet to be connected to a pipeline, a saddle connected with the housing, a turn plug having a rod, the turn plug cooperating with the saddle, and a drive for turning the valve body and formed as a piezoelectric drive, the piezoelectric drive including a piezoelectric generator of radially directed standing acoustic waves, which is connected with the housing and is connectable with a pulse current source, and a rotor operatively connected with the piezoelectric generator and kinematically connected with the rod of the turn plug so as to turn the turn plug when the rotor is actuated by the piezoelectric generator.

  6. The x-ray light valve: a potentially low-cost, digital radiographic imaging system--a liquid crystal cell design for chest radiography.

    PubMed

    Szeto, Timothy C; Webster, Christie Ann; Koprinarov, Ivaylo; Rowlands, J A

    2008-03-01

    Digital x-ray radiographic systems are desirable as they offer high quality images which can be processed, transferred, and stored without secondary steps. However, current clinical systems are extraordinarily expensive in comparison to film-based systems. Thus, there is a need for an economical digital imaging system for general radiology. The x-ray light valve (XLV) is a novel digital x-ray detector concept with the potential for high image quality and low cost. The XLV is comprised of a photoconductive detector layer and liquid crystal (LC) cell physically coupled in a sandwich structure. Upon exposure to x rays, charge is collected at the surface of the photoconductor, causing a change in the reflective properties of the LC cell. The visible image so formed can subsequently be digitized with an optical scanner. By choosing the properties of the LC cell in combination with the appropriate photoconductor thickness and bias potentials, the XLV can be optimized for various diagnostic imaging tasks. Specifically for chest radiography, we identified three potentially practical reflective cell designs by selecting from those commonly used in LC display technology. The relationship between reflectance and x-ray exposure (i.e., the characteristic curve) was determined for all three cells using a theoretical model. The results indicate that the reflective electrically controlled birefringence (r-ECB) cell is the preferred choice for chest radiography, provided that the characteristic curve can be shifted towards lower exposures. The feasibility of the shift of the characteristic curve is shown experimentally. The experimental results thus demonstrate that an XLV based on the r-ECB cell design exhibits a characteristic curve suitable for chest radiography.

  7. Determination of salivary cotinine through solid phase extraction using a bead-injection lab-on-valve approach hyphenated to hydrophilic interaction liquid chromatography.

    PubMed

    Ramdzan, Adlin N; Barreiros, Luísa; Almeida, M Inês G S; Kolev, Spas D; Segundo, Marcela A

    2016-01-15

    Cotinine, the first metabolite of nicotine, is often used as a biomarker in the monitoring of environmental tobacco smoke (ETS) exposure due to its long half-life. This paper reports on the development of an at-line automatic micro-solid phase extraction (μSPE) method for the determination of salivary cotinine followed by its analysis via hydrophilic interaction liquid chromatography (HILIC). The SPE methodology is based on the bead injection (BI) concept in a mesofluidic lab-on-valve (LOV) flow system to automatically perform all SPE steps. Three commercially available reversed-phase sorbents were tested, namely, Oasis HLB, Lichrolut EN and Focus, and the spherically shaped sorbents (i.e., Oasis HLB and Focus) provided better packing within the SPE column and hence higher column efficiency. An HILIC column was chosen based on its potential for achieving higher sensitivity and better retention of polar compounds such as cotinine. The method uses an isocratic program with acetonitrile:100mM ammonium acetate buffer, pH 5.8 in 95:5 v/v ratio as the mobile phase at a flow rate of 1.0 mL min(-1). Using this approach, the linear calibration range was from 10 to 1000 ng which corresponded to 5-500 μg L(-1). The corresponding μSPE-BI-LOV system was proven to be reliable in the handing and analysis of viscous biological samples such as saliva, achieving a sampling rate of 6h(-1) and a limit of detection and quantification of 1.5 and 3μgL(-1), respectively. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Propellant isolation shutoff valve program

    NASA Technical Reports Server (NTRS)

    Merritt, F. L.

    1973-01-01

    An analysis and design effort directed to advancing the state-of-the-art of space storable isolation valves for control of flow of the propellants liquid fluorine/hydrazine and Flox/monomethylhydrazine is discussed. Emphasis is on achieving zero liquid leakage and capability of withstanding missions up to 10 years in interplanetary space. Included is a study of all-metal poppet sealing theory, an evaluation of candidate seal configurations, a valve actuator trade-off study and design description of a pneumo-thermally actuated soft metal poppet seal valve. The concepts and analysis leading to the soft seal approach are documented. A theoretical evaluation of seal leakage versus seal loading, related finishes and yield strengths of various materials is provided. Application of a confined soft aluminum seal loaded to 2 to 3 times yield strength is recommended. Use of either an electro-mechanical or pneumatic actuator appears to be feasible for the application.

  9. Excess flow shutoff valve

    DOEpatents

    Kiffer, Micah S.; Tentarelli, Stephen Clyde

    2016-02-09

    Excess flow shutoff valve comprising a valve body, a valve plug, a partition, and an activation component where the valve plug, the partition, and activation component are disposed within the valve body. A suitable flow restriction is provided to create a pressure difference between the upstream end of the valve plug and the downstream end of the valve plug when fluid flows through the valve body. The pressure difference exceeds a target pressure difference needed to activate the activation component when fluid flow through the valve body is higher than a desired rate, and thereby closes the valve.

  10. Valve Disease

    MedlinePlus

    ... medicines for the rest of their lives. Valve surgery is usually an open heart technique. This means that surgeons use a heart-lung machine, because the heart must stop beating for a short time during surgery. In some patients, surgeons can repair or replace ...

  11. 46 CFR 53.05-1 - Safety valve requirements for steam boilers (modifies HG-400 and HG-401).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Safety valve requirements for steam boilers (modifies HG... (CONTINUED) MARINE ENGINEERING HEATING BOILERS Pressure Relieving Devices (Article 4) § 53.05-1 Safety valve requirements for steam boilers (modifies HG-400 and HG-401). (a) The pressure relief valve requirements and...

  12. 46 CFR 53.05-1 - Safety valve requirements for steam boilers (modifies HG-400 and HG-401).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Safety valve requirements for steam boilers (modifies HG... (CONTINUED) MARINE ENGINEERING HEATING BOILERS Pressure Relieving Devices (Article 4) § 53.05-1 Safety valve requirements for steam boilers (modifies HG-400 and HG-401). (a) The pressure relief valve requirements and...

  13. 46 CFR 53.05-1 - Safety valve requirements for steam boilers (modifies HG-400 and HG-401).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Safety valve requirements for steam boilers (modifies HG... (CONTINUED) MARINE ENGINEERING HEATING BOILERS Pressure Relieving Devices (Article 4) § 53.05-1 Safety valve requirements for steam boilers (modifies HG-400 and HG-401). (a) The pressure relief valve requirements and...

  14. 46 CFR 53.05-1 - Safety valve requirements for steam boilers (modifies HG-400 and HG-401).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Safety valve requirements for steam boilers (modifies HG... (CONTINUED) MARINE ENGINEERING HEATING BOILERS Pressure Relieving Devices (Article 4) § 53.05-1 Safety valve requirements for steam boilers (modifies HG-400 and HG-401). (a) The pressure relief valve requirements and...

  15. 46 CFR 53.05-1 - Safety valve requirements for steam boilers (modifies HG-400 and HG-401).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Safety valve requirements for steam boilers (modifies HG... (CONTINUED) MARINE ENGINEERING HEATING BOILERS Pressure Relieving Devices (Article 4) § 53.05-1 Safety valve requirements for steam boilers (modifies HG-400 and HG-401). (a) The pressure relief valve requirements and...

  16. Valve-less microdispenser

    NASA Astrophysics Data System (ADS)

    Tan, Ming Kwang; Xin, Wang; Lee, Weng Kent

    2015-11-01

    We demonstrate the concept of valve-less microdispenser to control of the liquid flow through the nozzle, by incorporating Leidenfrost effect into the nozzle design. When the nozzle is heated above the Leidenfrost point, a thin vapor layer is formed between the heated substrate and the liquid above it. The vapor pressure due to the presence of the vapor layer, together with the effect of surface tension of the liquid, exerted on the liquid-vapor interface, preventing the flow of the liquid through the nozzle. The experimental results shown that nozzles of diameter 400 micrometer and below, the nozzle temperature of 150 degree Celsius is sufficient to prevent the continuous flowing of the liquid, whereas for nozzles of diameter between 400 to 500 micrometer, the nozzle temperature needs to increase to 160 degree Celsius in order to prevent the continuous flowing of the liquid. When nozzle temperature below 160 degree Celsius, intermittent ejection of microdroplets, whose size is a function of nozzle temperature, is observed.

  17. Valve mechanism lubrication system for an overhead valve engine

    SciTech Connect

    Kronich, P.G.

    1986-07-22

    In an internal combustion engine, including a crankcase, an oil sump, push rods for operating the valves of the engine, a rocker box for housing the valve actuating mechanism, a lubrication system for lubricating the valve actuating mechanism is described which consists of: a first hollow tube for housing a first of the push rods, and first tube having one end open to the crankcase, and an opposite end open to the rocker box, for conducting oil mist from the crankcase to the rocker box to lubricate the valve rocker mechanism; a second hollow tube for housing a second push rod, the second tube having one end open to the rocker box and an opposite end open to a breather chamber for conducting liquid oil and oil mist from the rocker box to the breather chamber, the breather chamber being vented to the atmosphere; an oil drain passage for conducting liquid oil from the breather chamber to the oil sump; and baffle means in the rocker box for causing the oil mist entering the rocker box from the first tube to flow past the valve actuating mechanism for lubrication thereof before flowing from the rocker box into the second tube.

  18. Semitoroidal-diaphragm cavitating valve designed for bipropellant flow control

    NASA Technical Reports Server (NTRS)

    Young, A. L.

    1969-01-01

    Valve controls the flow of bipropellant liquids in rocket engines. Throttling and cavitation of the liquids are controlled by axial deflections of a semitoroidal metal diaphram. The valve is highly resistant to corrosion and leakage, and should be useful in food processing and chemical industries.

  19. Dump valve

    SciTech Connect

    Webber, J.C.

    1981-06-23

    A swab assembly is provided having a dump valve responsive to fluid pressure and drag which will dump the fluid load should either fluid load or drag or the effect of both fluid load and drag become abnormal. Also if the fluid pressure and/or drag become abnormal, the fluid load on the cup will be released and wash away foreign material causing abnormal drag. When the cup is dumped the pulling capabilities of the wireline truck can concentrate on overcoming the drag. The dump valve opens to wide open position and remains open to dump the fluid to assist in washing away solid materials above the cup. A swab assembly also is provided which with normal drag and an overload, may be pulled relatively slowly, but if pulled too rapidly will result in the load on the swab being dumped to protect the swab assembly and the pulling apparatus from damage. 15 claims.

  20. ELECTROSTRICTION VALVE

    DOEpatents

    Kippenhan, D.O.

    1962-09-25

    An accurately controlled, pulse gas valve is designed capable of delivering output pulses which vary in length from one-tenth millisecond to one second or more, repeated at intervals of a few milliseconds or- more. The pulsed gas valve comprises a column formed of barium titanate discs mounted in stacked relation and electrically connected in parallel, with means for applying voltage across the discs to cause them to expand and effect a mechanical elongation axially of the column. The column is mounted within an enclosure having an inlet port and an outlet port with an internal seat in communication with the outlet port, such that a plug secured to the end of the column will engage the seat of the outlet port to close the outlet port in response to the application of voltage is regulated by a conventional electronic timing circuit connected to the column. (AEC)

  1. Automatic shutoff valve

    NASA Technical Reports Server (NTRS)

    Hawkins, S. F.; Overbey, C. W.

    1980-01-01

    Cellulose-sponge disk absorbs incoming water and expands with enough force to shut valve. When water recedes, valve opens by squeezing sponge dry to its original size. This direct mechanical action is considered more reliable than solenoid valve.

  2. Automatic shutoff valve

    NASA Technical Reports Server (NTRS)

    Hawkins, S. F.; Overbey, C. W.

    1980-01-01

    Cellulose-sponge disk absorbs incoming water and expands with enough force to shut valve. When water recedes, valve opens by squeezing sponge dry to its original size. This direct mechanical action is considered more reliable than solenoid valve.

  3. Mitral Valve Disease

    MedlinePlus

    ... Tricuspid Valve Disease Cardiac Rhythm Disturbances Thoracic Aortic Aneurysm Pediatric and Congenital Heart Disease Heart abnormalities that are ... Transplantation End-stage Lung Disease Adult Lung Transplantation Pediatric Lung ... Aortic Aneurysm Mitral Valve Disease Overview The mitral valve is ...

  4. Magnetically operated check valve

    NASA Technical Reports Server (NTRS)

    Morris, Brian G. (Inventor); Bozeman, Richard J., Jr. (Inventor)

    1994-01-01

    A magnetically operated check valve is disclosed. The valve is comprised of a valve body and a movable poppet disposed therein. A magnet attracts the poppet to hold the valve shut until the force of fluid flow through the valve overcomes the magnetic attraction and moves the poppet to an unseated, open position. The poppet and magnet are configured and disposed to trap a magnetically attracted particulate and prevent it from flowing to a valve seating region.

  5. Magnetically operated check valve

    NASA Astrophysics Data System (ADS)

    Morris, Brian G.; Bozeman, Richard J., Jr.

    1994-06-01

    A magnetically operated check valve is disclosed. The valve is comprised of a valve body and a movable poppet disposed therein. A magnet attracts the poppet to hold the valve shut until the force of fluid flow through the valve overcomes the magnetic attraction and moves the poppet to an unseated, open position. The poppet and magnet are configured and disposed to trap a magnetically attracted particulate and prevent it from flowing to a valve seating region.

  6. Study on high reliability safety valve for railway vehicle

    NASA Astrophysics Data System (ADS)

    Zhang, Xuan; Chen, Ruikun; Zhang, Shixi; Xu, BuDu

    2017-09-01

    Now, the realization of most of the functions of the railway vehicles rely on compressed air, so the demand for compressed air is growing higher and higher. This safety valve is a protection device for pressure limitation and pressure relief in an air supply system of railway vehicles. I am going to introduce the structure, operating principle, research and development process of the safety valve designed by our company in this document.

  7. Speeding earthquake disaster relief

    USGS Publications Warehouse

    Mortensen, Carl; Donlin, Carolyn; Page, Robert A.; Ward, Peter

    1995-01-01

    In coping with recent multibillion-dollar earthquake disasters, scientists and emergency managers have found new ways to speed and improve relief efforts. This progress is founded on the rapid availability of earthquake information from seismograph networks.

  8. Fast-Acting Valve

    NASA Technical Reports Server (NTRS)

    Wojciechowski, Bogdan V. (Inventor); Pegg, Robert J. (Inventor)

    2003-01-01

    A fast-acting valve includes an annular valve seat that defines an annular valve orifice between the edges of the annular valve seat, an annular valve plug sized to cover the valve orifice when the valve is closed, and a valve-plug holder for moving the annular valve plug on and off the annular valve seat. The use of an annular orifice reduces the characteristic distance between the edges of the valve seat. Rather than this distance being equal to the diameter of the orifice, as it is for a conventional circular orifice, the characteristic distance equals the distance between the inner and outer radii (for a circular annulus). The reduced characteristic distance greatly reduces the gap required between the annular valve plug and the annular valve seat for the valve to be fully open, thereby greatly reducing the required stroke and corresponding speed and acceleration of the annular valve plug. The use of a valve-plug holder that is under independent control to move the annular valve plug between its open and closed positions is important for achieving controllable fast operation of the valve.

  9. Liquid Level Control System.

    DTIC Science & Technology

    A system for controlling liquid flow from an inlet into a tank comprising a normally closed poppet valve controlled by dual pressure chambers each...containing a diaphragm movable by the pressure of the liquid in the inlet to cause the valve to close. Pressure against the diaphragms is relieved by

  10. 77 FR 19533 - Changes in the Statutory Authority for Petitions for Relief

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-02

    ... Petitions for Relief AGENCY: U.S. Customs and Border Protection, Department of Homeland Security. ACTION... authorities regarding petitions for relief from a fine, penalty, forfeiture, or liquidated damages under a law... alleged to have committed a violation, or a breach of a bond condition, to petition for relief. This...

  11. Percutaneous Relief of Tension Pneumomediastinum in a Child

    SciTech Connect

    Chau, Helen Hoi-lun; Kwok, Philip Chong-hei; Lai, Albert Kwok-hung; Fan, Tsz Wo; Chan, Susan Chi-hum; Miu, Ting Yat; Chan, Grace Lai-har

    2003-11-15

    The purpose of this article was to describe the experience of relieving tension pneumomediastinum by a fluoroscopic-guided percutaneous method. We inserted a percutaneous drainage catheter with a Heimlich valve under fluoroscopic guidance to relieve the tension pneumomediastinum in a 2-year-old girl who suffered from dermatomyositis with lung involvement. This allowed immediate relief without the need for surgery. The procedure was repeated for relapsed tension pneumomediastinum. Good immediate results were achieved in each attempt. We conclude that percutaneous relief of pneumomediastinum under fluoroscopic guidance can be performed safely and rapidly in patients not fit for surgery.

  12. A capillary valve for microfluidic systems.

    SciTech Connect

    Cummings, Eric B.; Kanouff, Michael P.; Rush, Brian M.

    2004-10-01

    Microfluidic systems are becoming increasingly complicated as the number of applications grows. The use of microfluidic systems for chemical and biological agent detection, for example, requires that a given sample be subjected to many process steps, which requires microvalves to control the position and transport of the sample. Each microfluidic application has its own specific valve requirements and this has precipitated the wide variety of valve designs reported in the literature. Each of these valve designs has its strengths and weaknesses. The strength of the valve design proposed here is its simplicity, which makes it easy to fabricate, easy to actuate, and easy to integrate with a microfluidic system. It can be applied to either gas phase or liquid phase systems. This novel design uses a secondary fluid to stop the flow of the primary fluid in the system. The secondary fluid must be chosen based on the type of flow that it must stop. A dielectric fluid must be used for a liquid phase flow driven by electroosmosis, and a liquid with a large surface tension should be used to stop a gas phase flow driven by a weak pressure differential. Experiments were carried out investigating certain critical functions of the design. These experiments verified that the secondary fluid can be reversibly moved between its 'valve opened' and 'valve closed' positions, where the secondary fluid remained as one contiguous piece during this transport process. The experiments also verified that when Fluorinert is used as the secondary fluid, the valve can break an electric circuit. It was found necessary to apply a hydrophobic coating to the microchannels to stop the primary fluid, an aqueous electrolyte, from wicking past the Fluorinert and short-circuiting the valve. A simple model was used to develop valve designs that could be closed using an electrokinetic pump, and re-opened by simply turning the pump off and allowing capillary forces to push the secondary fluid back into its

  13. Oral Intake of a Liquid High-Molecular-Weight Hyaluronan Associated with Relief of Chronic Pain and Reduced Use of Pain Medication: Results of a Randomized, Placebo-Controlled Double-Blind Pilot Study

    PubMed Central

    Attridge, Victoria L.; Lenninger, Miki R.; Benson, Kathleen F.

    2015-01-01

    Abstract The goal for this study was to evaluate the effects of daily oral intake of a consumable liquid fermentate containing high-molecular-weight hyaluronan, as well as to perform a basic evaluation of safety and tolerability. A randomized, double-blind placebo-controlled study design was used to examine the effects of oral intake of hyaluronan on chronic pain conditions. Safety assessment included a complete blood count with differential, blood chemistry and electrocardiogram. The study duration was 4 weeks, where three tablespoons (45 mL) product or placebo was ingested during the first 2 weeks, and two tablespoons (30 mL) was consumed during the last 2 weeks. Seventy-eight people between the age of 19 and 71 years enrolled, and 72 people completed the study. Statistical analysis was performed using the two-tailed independent t-test for between-group significance and using the paired t-test for within-group significance. A reduction in pain scores was seen after 2 weeks of consumption of both placebo (P<.1) and active (P<.065) product; the reduction was more pronounced in the group consuming the active test product. Using “within-subject” analysis, a highly significant reduction in chronic pain scores was seen after 2 weeks of consumption of three tablespoons of active product (P<.001), whereas only a mild nonsignificant reduction in pain scores was seen in the placebo group. During the reduced intake for the last 2 weeks of study participation, pain scores showed a slight increase. During the last 2 weeks, a significant increase in the quality of sleep (P<.005) and level of physical energy (P<.05) was seen. The pain reduction during the initial 2 weeks was associated with significant reduction in the use of pain medication (P<.05). Consumption of an oral liquid formula containing high-molecular-weight hyaluronan was associated with relief of chronic pain. PMID:25415767

  14. Oral intake of a liquid high-molecular-weight hyaluronan associated with relief of chronic pain and reduced use of pain medication: results of a randomized, placebo-controlled double-blind pilot study.

    PubMed

    Jensen, Gitte S; Attridge, Victoria L; Lenninger, Miki R; Benson, Kathleen F

    2015-01-01

    The goal for this study was to evaluate the effects of daily oral intake of a consumable liquid fermentate containing high-molecular-weight hyaluronan, as well as to perform a basic evaluation of safety and tolerability. A randomized, double-blind placebo-controlled study design was used to examine the effects of oral intake of hyaluronan on chronic pain conditions. Safety assessment included a complete blood count with differential, blood chemistry and electrocardiogram. The study duration was 4 weeks, where three tablespoons (45 mL) product or placebo was ingested during the first 2 weeks, and two tablespoons (30 mL) was consumed during the last 2 weeks. Seventy-eight people between the age of 19 and 71 years enrolled, and 72 people completed the study. Statistical analysis was performed using the two-tailed independent t-test for between-group significance and using the paired t-test for within-group significance. A reduction in pain scores was seen after 2 weeks of consumption of both placebo (P<.1) and active (P<.065) product; the reduction was more pronounced in the group consuming the active test product. Using "within-subject" analysis, a highly significant reduction in chronic pain scores was seen after 2 weeks of consumption of three tablespoons of active product (P<.001), whereas only a mild nonsignificant reduction in pain scores was seen in the placebo group. During the reduced intake for the last 2 weeks of study participation, pain scores showed a slight increase. During the last 2 weeks, a significant increase in the quality of sleep (P<.005) and level of physical energy (P<.05) was seen. The pain reduction during the initial 2 weeks was associated with significant reduction in the use of pain medication (P<.05). Consumption of an oral liquid formula containing high-molecular-weight hyaluronan was associated with relief of chronic pain.

  15. Joule-Thomson Expander Without Check Valves

    NASA Technical Reports Server (NTRS)

    Chan, C. K.; Gatewood, J. R.

    1989-01-01

    Cooling effected by bidirectional, reciprocating flow of gas. Type of Joule-Thomson (J-T) expander for cryogenic cooling requires no check valves to prevent reverse flow of coolant. More reliable than conventional J-T expander, containing network of check valves, each potential source of failure. Gas flows alternately from left to right and right to left. Heat load cooled by evaporation of liquid from left or right compartment, whichever at lower pressure.

  16. Lightweight Right-Angle Valve For Cryogenics

    NASA Technical Reports Server (NTRS)

    Calhoun, Richard B.

    1993-01-01

    Lightweight right-angle valve isolates pressurized liquid or gas stream from vacuum over wide range of temperatures from ambient down to cryogenic. Sized to fit tubes of types ordinarily used in cryogenic equipment. Maintains isolation, without need for manual adjustment of packing gland as pressure and temperature vary. Mass of valve less than 60 grams. Made of off-the-shelf parts and few simple custom-machined parts.

  17. Remote actuated valve implant

    DOEpatents

    McKnight, Timothy E; Johnson, Anthony; Moise, Jr., Kenneth J; Ericson, Milton Nance; Baba, Justin S; Wilgen, John B; Evans, III, Boyd McCutchen

    2014-02-25

    Valve implant systems positionable within a flow passage, the systems having an inlet, an outlet, and a remotely activatable valve between the inlet and outlet, with the valves being operable to provide intermittent occlusion of the flow path. A remote field is applied to provide thermal or magnetic activation of the valves.

  18. Remote actuated valve implant

    DOEpatents

    McKnight, Timothy E.; Johnson, Anthony; Moise, Kenneth J.; Ericson, Milton Nance; Baba, Justin S.; Wilgen, John B.; Evans, Boyd Mccutchen

    2016-05-10

    Valve implant systems positionable within a flow passage, the systems having an inlet, an outlet, and a remotely activatable valve between the inlet and outlet, with the valves being operable to provide intermittent occlusion of the flow path. A remote field is applied to provide thermal or magnetic activation of the valves.

  19. Rotary pneumatic valve

    DOEpatents

    Hardee, Harry C.

    1991-01-01

    A rotary pneumatic valve which is thrust balanced and the pneumatic pressure developed produces only radial loads on the valve cylinder producing negligible resistance and thus minimal torque on the bearings of the valve. The valve is multiplexed such that at least two complete switching cycles occur for each revolution of the cylinder spindle.

  20. Vitrification of heart valve tissues.

    PubMed

    Brockbank, Kelvin G M; Chen, Zhenzhen; Greene, Elizabeth D; Campbell, Lia H

    2015-01-01

    Application of the original vitrification protocol used for pieces of heart valves to intact heart valves has evolved over time. Ice-free cryopreservation by Protocol 1 using VS55 is limited to small samples where relatively rapid cooling and warming rates are possible. VS55 cryopreservation typically provides extracellular matrix preservation with approximately 80 % cell viability and tissue function compared with fresh untreated tissues. In contrast, ice-free cryopreservation using VS83, Protocols 2 and 3, has several advantages over conventional cryopreservation methods and VS55 preservation, including long-term preservation capability at -80 °C; better matrix preservation than freezing with retention of material properties; very low cell viability, reducing the risks of an immune reaction in vivo; reduced risks of microbial contamination associated with use of liquid nitrogen; improved in vivo functions; no significant recipient allogeneic immune response; simplified manufacturing process; increased operator safety because liquid nitrogen is not used; and reduced manufacturing costs.

  1. Whole Teflon valves for handling droplets.

    PubMed

    Cybulski, Olgierd; Jakiela, Slawomir; Garstecki, Piotr

    2016-06-21

    We propose and test a new whole-Teflon gate valve for handling droplets. The valve allows droplet plugs to pass through without disturbing them. This is possible due to the geometric design, the choice of material and lack of any pulses of flow generated by closing or opening the valve. The duct through the valve resembles a simple segment of tubing, without constrictions, change in lumen or side pockets. There are no extra sealing materials with different wettability or chemical resistance. The only material exposed to liquids is FEP Teflon, which is resistant to aggressive chemicals and fully biocompatible. The valve can be integrated into microfluidic systems: we demonstrate a complex system for culturing bacteria in hundreds of microliter droplet chemostats. The valve effectively isolates modules of the system to increase precision of operations on droplets. We verified that the valve allowed millions of droplet plugs to safely pass through, without any cross-contamination with bacteria between the droplets. The valve can be used in automating complex microfluidic systems for experiments in biochemistry, biology and organic chemistry.

  2. Double valve Implantation

    PubMed Central

    Stassano, Paolo; Mannacio, Vito; Musumeci, Antonino; Golino, Alessandro; Maida, Piero; Ferrigno, Vincenzo; Buonocore, Gaetano; Spampinato, Nicola

    1991-01-01

    From January 1976 through December 1987, 194 patients with a mean age of 43.3 ± 13.7 years (range, 11 to 74 years) underwent double (mitral and aortic) replacement of native valves with 8 types of bioprostheses: Carpentier-Edwards, 127 valves; Hancock, 76 valves; Liotta-Bioimplant, 57 valves; Ionescu-Shiley, 53 valves; Vascor, 27 valves; Carpentier-Edwards Pericardial, 22 valves; Angell-Shiley, 20 valves; and Implamedic, 6 valves. Concomitant cardiac procedures were performed in 25 patients (12.8%). There were 18 operative deaths (9.27%). Our retrospective analysis was restricted to 352 bioprostheses implanted in the 176 patients who survived surgery and were considered at risk for valve tissue failure. The overall cumulative duration of follow-up was 1,174.1 patient-years (range, 1 to 13 years). The durations of follow-up for specific valves were: Carpentier-Edwards, 920.2 valve-years; Hancock, 383.8 valve-years; Liotta-Bioimplant, 310.2 valve-years; Ionescu-Shiley, 357.7 valve-years; Vascor, 131.2 valve-years; Carpentier-Edwards Pericardial, 52.0 valve-years; Angell-Shiley, 167.0 valve-years; and Implamedic, 31.0 valve-years. Thirty patients had thromboembolic accidents, for a linearized incidence of 2.5% per patient-year. At 13 years, the actuarial freedom from thromboembolic accidents was 85.8% ± 10.7%. Nine patients had endocarditis, for a linearized incidence of 0.7% per patient-year. At 13 years, the actuarial freedom from endocarditis was 92.0% ± 1.5%. Twenty-four patients had valve tissue failure, for a cumulative linearized incidence of 1.87% per valve-year. The cumulative actuarial probability of freedom from valve tissue failure was 78.6% ± 3.7% at 10 years and 51.2% ± 10.7% at 13 years. The 24 patients with valve tissue failure all underwent reoperation: 20 of these had double valve replacement, 3 had aortic valve replacement alone, and 1 had mitral valve replacement alone. The mean interval between initial valve implantation and reoperation was

  3. Dual stage check valve

    NASA Technical Reports Server (NTRS)

    Whitten, D. E. (Inventor)

    1973-01-01

    A dual stage seat valve head arrangement is described which consists of a primary sealing point located between a fixed orifice seat and a valve poppet, and a secondary sealing point between an orifice poppet and a valve poppet. Upstream of the valve orifice is a flexible, convoluted metal diaphragm attached to the orifice poppet. Downstream of the valve orifice, a finger spring exerts a force against the valve poppet, tending to keep the valve in a closed position. The series arrangement of a double seat and poppet is able to tolerate small particle contamination while minimizing chatter by controlling throttling or metering across the secondary seat, thus preserving the primary sealing surface.

  4. Throttle valve control device

    SciTech Connect

    Nishida, M.; Katashiba, H.

    1988-03-01

    This patent describes a valve control device which comprises: a valve shaft for operating a throttle valve; a differential gear device having first and second drive gears, for driving the valve shaft; first and second electronic control actuators for rotating the first and second drive gear, respectively; and a sensor for detecting the degree of opening of the throttle valve, so that the operation of the throttle valve is controlled by the electronic control actuators while the degree of opening of the throttle valve is being detected.

  5. Bellows sealed plug valve

    DOEpatents

    Dukas, Jr., Stephen J.

    1990-01-01

    A bellows sealed plug valve includes a valve body having an inlet passage and an outlet passage, a valve chamber between the inlet and outlet passages. A valve plug has substantially the same shape as the valve chamber and is rotatably disposed therein. A shaft is movable linearly in response to a signal from a valve actuator. A bellows is sealingly disposed between the valve chamber and the valve actuator and means are located between the bellows and the valve plug for converting linear movement of the shaft connected to the valve actuator to rotational movement of the plug. Various means are disclosed including helical thread mechanism, clevis mechanism and rack and pinion mechanism, all for converting linear motion to rotational motion.

  6. Vacuum breaker valve assembly

    DOEpatents

    Thompson, Jeffrey L.; Upton, Hubert Allen

    1999-04-27

    Breaker valve assemblies for a simplified boiling water nuclear reactor are described. The breaker valve assembly, in one form, includes a valve body and a breaker valve. The valve body includes an interior chamber, and an inlet passage extends from the chamber and through an inlet opening to facilitate transporting particles from outside of the valve body to the interior chamber. The breaker valve is positioned in the chamber and is configured to substantially seal the inlet opening. Particularly, the breaker valve includes a disk which is sized to cover the inlet opening. The disk is movably coupled to the valve body and is configured to move substantially concentrically with respect to the valve opening between a first position, where the disk completely covers the inlet opening, and a second position, where the disk does not completely cover the inlet opening.

  7. Scissor thrust valve actuator

    DOEpatents

    DeWall, Kevin G.; Watkins, John C; Nitzel, Michael E.

    2006-08-29

    Apparatus for actuating a valve includes a support frame and at least one valve driving linkage arm, one end of which is rotatably connected to a valve stem of the valve and the other end of which is rotatably connected to a screw block. A motor connected to the frame is operatively connected to a motor driven shaft which is in threaded screw driving relationship with the screw block. The motor rotates the motor driven shaft which drives translational movement of the screw block which drives rotatable movement of the valve driving linkage arm which drives translational movement of the valve stem. The valve actuator may further include a sensory control element disposed in operative relationship with the valve stem, the sensory control element being adapted to provide control over the position of the valve stem by at least sensing the travel and/or position of the valve stem.

  8. Valve-in-Valve Replacement Using a Sutureless Aortic Valve

    PubMed Central

    Dohmen, Pascal M.; Lehmkuhl, Lukas; Borger, Michael A.; Misfeld, Martin; Mohr, Friedrich W.

    2016-01-01

    Patient: Female, 61 Final Diagnosis: Tissue degeneration Symptoms: Dyspnea Medication: — Clinical Procedure: Redo valve replacement Specialty: Surgery Objective: Rare disease Background: We present a unique case of a 61-year-old female patient with homograft deterioration after redo surgery for prosthetic valve endocarditis with root abscess. Case Report: The first operation was performed for type A dissection with root, arch, and elephant trunk replacement of the thoracic aorta. The present re-redo surgery was performed as valve-in-valve with a sutureless aortic biopros-thesis. The postoperative course was uneventful and the patient was discharged on day 6. Conclusions: The current case report demonstrates that sutureless bioprostheses are an attractive option for surgical valve-in-valve procedures, which can reduce morbidity and mortality. PMID:27694795

  9. Heart valve surgery - series (image)

    MedlinePlus

    There are four valves in the heart: aortic valve, mitral valve, tricuspid valve, and pulmonary valve. The valves are designed to control the direction of blood flow through the heart. The opening and closing of the heart valves produce the heart-beat sounds.

  10. Valve for fluid control

    DOEpatents

    Oborny, Michael C.; Paul, Phillip H.; Hencken, Kenneth R.; Frye-Mason, Gregory C.; Manginell, Ronald P.

    2001-01-01

    A valve for controlling fluid flows. This valve, which includes both an actuation device and a valve body provides: the ability to incorporate both the actuation device and valve into a unitary structure that can be placed onto a microchip, the ability to generate higher actuation pressures and thus control higher fluid pressures than conventional microvalves, and a device that draws only microwatts of power. An electrokinetic pump that converts electric potential to hydraulic force is used to operate, or actuate, the valve.

  11. Magnetically operated check valve

    NASA Astrophysics Data System (ADS)

    Morris, Brian G.; Bozeman, Richard J., Jr.

    1993-03-01

    A magnetically operated check valve is disclosed having, in one aspect, a valve body and a movable poppet disposed therein. A magnet attracts the poppet to hold the valve shut until the force of fluid flow through the valve overcomes the magnetic attraction and moves the poppet to an unseated, open position. The poppet and magnet are configured and disposed to trap a magnetically attracted particulate and prevent it from flowing to a valve seating region.

  12. Lubricator valve apparatus

    SciTech Connect

    Brooks, R. T.

    1984-10-16

    A lubricator valve assembly comprises a reciprocably rotatable ball valve which is operated between open and closed positions solely through the selective application of control pressures and/or tubing pressure above the valve to a double acting sleeve type actuating piston. One end of the actuating piston has a valving piston formed thereon which cooperates with a seal bore in the housing to effect the opening or closing of a bypass fluid passage extending from a region below the ball valve to a region above the ball valve. Such valving piston also functions as part of a lost motion connection between the actuating sleeve piston and a reciprocable actuator for rotating the ball valve. In opening the ball valve, the valving piston first moves upwardly to establish a fluid bypass around the closed ball valve and then establishes contact with the actuator to rotate the ball valve to an open position. The same fluid bypass may be utilized to pump through fluid around the closed ball valve by applying fluid pressure above the ball valve. Improved sealing elements for the ball valve are also provided.

  13. Transcatheter Mitral Valve Repair Therapies: Evolution, Status and Challenges.

    PubMed

    Espiritu, Daniella; Onohara, Daisuke; Kalra, Kanika; Sarin, Eric L; Padala, Muralidhar

    2017-02-01

    Mitral regurgitation is a common cardiac valve lesion, developing from primary lesions of the mitral valve or secondary to cardiomyopathies. Moderate or higher severity of mitral regurgitation imposes significant volume overload on the left ventricle, causing permanent structural and functional deterioration of the myocardium and heart failure. Timely correction of regurgitation is essential to preserve cardiac function, but surgical mitral valve repair is often delayed due to the risks of open heart surgery. Since correction of mitral regurgitation can provide symptomatic relief and halt progressive cardiac dysfunction, transcatheter mitral valve repair technologies are emerging as alternative therapies. In this approach, the mitral valve is repaired either with sutures or implants that are delivered to the native valve on catheters introduced into the cardiovascular system under image guidance, through small vascular or ventricular ports. Several transcatheter mitral valve technologies are in development, but limited clinical success has been achieved. In this review, we present a historical perspective of mitral valve repair, review the transcatheter technologies emerging from surgical concepts, the challenges they face in achieving successful clinical application, and the increasing rigor of safety and durability standards for new transcatheter valve technologies.

  14. Hydraulically actuated gas exchange valve assembly and engine using same

    DOEpatents

    Carroll, Thomas S.; Taylor, Gregory O.

    2002-09-03

    An engine comprises a housing that defines a hollow piston cavity that is separated from a gas passage by a valve seat. The housing further defines a biasing hydraulic cavity and a control hydraulic cavity. A gas valve member is also included in the engine and is movable relative to the valve seat between an open position at which the hollow piston cavity is open to the gas passage and a closed position in which the hollow piston cavity is blocked from the gas passage. The gas valve member includes a ring mounted on a valve piece and a retainer positioned between the ring and the valve piece. A closing hydraulic surface is included on the gas valve member and is exposed to liquid pressure in the biasing hydraulic cavity.

  15. Progress in Valve Modeling at Stennis Space Center

    NASA Technical Reports Server (NTRS)

    Daines, Russell L.; Woods, Jody L.; Sulyma, Peter

    2003-01-01

    Understanding valve behavior will aid testing of rocket components at Stennis Space Center. The authors of this viewgraph presentation have developed a computational model for a cryogenic liquid control valve, and a gas pressure regulator valve. The model is a compressible/incompressible pressure-based FDNS code from Marshall Space Flight Center (MSFC). It is a k-epsilon turbulence model with wall functions.

  16. What a Relief!

    ERIC Educational Resources Information Center

    Honeycutt, Kevin

    1999-01-01

    Describes an art activity for high school students in which they create relief sculptures by rendering a two-dimensional design and then transferring that design onto a slab of clay. Stresses that this activity provides teachers with a means for introducing students to three-dimensional art. (CMK)

  17. A reversible molecular valve

    PubMed Central

    Nguyen, Thoi D.; Tseng, Hsian-Rong; Celestre, Paul C.; Flood, Amar H.; Liu, Yi; Stoddart, J. Fraser; Zink, Jeffrey I.

    2005-01-01

    In everyday life, a macroscopic valve is a device with a movable control element that regulates the flow of gases or liquids by blocking and opening passageways. Construction of such a device on the nanoscale level requires (i) suitably proportioned movable control elements, (ii) a method for operating them on demand, and (iii) appropriately sized passageways. These three conditions can be fulfilled by attaching organic, mechanically interlocked, linear motor molecules that can be operated under chemical, electrical, or optical stimuli to stable inorganic porous frameworks (i.e., by self-assembling organic machinery on top of an inorganic chassis). In this article, we demonstrate a reversibly operating nanovalve that can be turned on and off by redox chemistry. It traps and releases molecules from a maze of nanoscopic passageways in silica by controlling the operation of redox-activated bistable [2]rotaxane molecules tethered to the openings of nanopores leading out of a nanoscale reservoir. PMID:16006520

  18. Quickly Removable Valve

    NASA Technical Reports Server (NTRS)

    Robbins, John S.

    1988-01-01

    Unit removed with minimal disturbance. Valve inlet and outlet ports adjacent to each other on same side of valve body. Ports inserted into special manifold on fluid line. Valve body attached to manifold by four bolts or, alternatively, by toggle clamps. Electromechanical actuator moves in direction parallel to fluid line to open and close valve. When necessary to clean valve, removed simply by opening bolts or toggle clamps. No need to move or separate ports of fluid line. Valve useful where disturbance of fluid line detrimental or where fast maintenance essential - in oil and chemical industries, automotive vehicles, aircraft, and powerplants.

  19. Quickly Removable Valve

    NASA Technical Reports Server (NTRS)

    Robbins, John S.

    1988-01-01

    Unit removed with minimal disturbance. Valve inlet and outlet ports adjacent to each other on same side of valve body. Ports inserted into special manifold on fluid line. Valve body attached to manifold by four bolts or, alternatively, by toggle clamps. Electromechanical actuator moves in direction parallel to fluid line to open and close valve. When necessary to clean valve, removed simply by opening bolts or toggle clamps. No need to move or separate ports of fluid line. Valve useful where disturbance of fluid line detrimental or where fast maintenance essential - in oil and chemical industries, automotive vehicles, aircraft, and powerplants.

  20. Fast acting check valve

    NASA Technical Reports Server (NTRS)

    Perkins, Gerald S. (Inventor)

    1979-01-01

    A check valve which closes more rapidly to prevent wearing of the valve seat and of the valve member that seals thereagainst, including a solenoid or other actuator that aids the normal spring to quickly close the valve at approximately the time when downpath fluid flow would stop, the actuator then being deenergized. The control circuit that operates the actuator can include a pair of pressure sensors sensing pressure both upstream and downstream from the valve seat. Where the valve is utilized to control flow to or from a piston pump, energization of the actuator can be controlled by sensing when the pump piston reaches its extreme of travel.