Science.gov

Sample records for pressure relief valve

  1. Inexpensive Pressure-Relief Valve

    NASA Technical Reports Server (NTRS)

    Theordore, E. A.

    1985-01-01

    Simple device vents excess low-pressure gas. Inexpensive pressure relief valve built from polyvinylchloride pipe. Valve suitable for low pressure-- 25 to 50 cm of mercury-- and flow rates up to 14 m3/min.

  2. Dual rate pressure relief valve

    NASA Technical Reports Server (NTRS)

    Steeneken, J.

    1968-01-01

    Pressure relief valve vents at a slow bleed rate at one pressure level and at a higher bleed rate at a higher pressure level. The value housing contains a sleeve, inlet port, outlet port, an orifice, a ball and seat arrangement, and a belleville spring diaphragm.

  3. Pressure Relief Valve

    NASA Technical Reports Server (NTRS)

    1985-01-01

    "Sputtering" is the process of applying film-like metal coatings onto a surface by bombarding the coating material with electrocharged ions. This causes the material to disintegrate and relocate on the substrate an atom layer at a time. The process allows a variety of coating materials to be deposited on various surfaces. Deposition Technology, Inc. (DTI) uses "sputtering" for window films, packaging materials, etc. Valves installed on two vacuum chambers which are part of DTI's system, were developed by Lewis Research Center and detailed in Tech Briefs. The valve protects the environment and frees the operator from monitoring the chamber venting.

  4. Pressure relief valve/safety relief valve testing

    SciTech Connect

    Murray, W.A.; Hamm, E.R.; Barber, J.R.

    1994-02-01

    Pressure vessels and piping systems are protected form overpressurization by pressure relief valves. These safety features are required to be tested-inspected on some periodic basis and, in most cases witnessed by a third party inspector. As a result nonconformances found by third parties Westinghouse Hanford Company initiated a task team to develop a pressure safety program. This paper reveals their findings.

  5. Pressure relief valve types and selection

    SciTech Connect

    Emerson, G.B.

    1988-05-01

    Pressure relief valves are one of the few types of equipment purchased and installed with the hope that they'll never be used. From the production viewpoint, a pressure relief valve produces nothing, yet it is very capable of disrupting a production operation or process. From a safety standpoint, a pressure relief valve must open in certain emergency conditions and also close when the emergency condition has been alleviated. Much depends upon proper selection of the type of pressure relief valve best suited for the intended service. The six figures in this article provide a summary of basic pressure relief valve types - weight loaded, direct spring operated, and pilot operated - outlining the operation and some pros and cons of each type. It is intended to be relative and not absolute. The specific application, prior experience, available commercial or special valve configurations, coupled with various accessories (such as a pilot filter for pilot operated valves in dirty service or a rupture disc upstream of a pressure relief valve), and the location of the valve in the system may allow the use of an otherwise unacceptable valve type.

  6. 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.

  7. 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... AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.59 Spring loaded pressure relief valve. A spring loaded pressure relief valve must— (a) Be set at a...

  8. 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... AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.59 Spring loaded pressure relief valve. A spring loaded pressure relief valve must— (a) Be set at a...

  9. 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... AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.59 Spring loaded pressure relief valve. A spring loaded pressure relief valve must— (a) Be set at a...

  10. 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... AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.59 Spring loaded pressure relief valve. A spring loaded pressure relief valve must— (a) Be set at a...

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. 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...

  17. 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...

  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, 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...

  20. 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...

  1. 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...

  2. 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...

  3. 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...

  4. 46 CFR 154.1846 - Relief valves: Changing set pressure.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) At each relief valve. ... 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...

  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. Check valve installation in pilot operated relief valve prevents reverse pressurization

    NASA Technical Reports Server (NTRS)

    Oswalt, L.

    1966-01-01

    Two check valves prevent reverse flow through pilot-operated relief valves of differential area piston design. Title valves control pressure flow to ensure that the piston dome pressure is always at least as great as the main relief valve discharge pressure.

  7. 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...

  8. Dual valve plate two-way pressure relief valve

    NASA Astrophysics Data System (ADS)

    Angeli, Robert J.

    1994-02-01

    There is disclosed a two-way valve which includes dual valve plates to be positioned between first and second chambers having varying pressure therein, to relieve excess pressure in either chamber by permitting fluid flow from one chamber to the other. The valve includes a body portion having disposed therein dual valve plates. In the equilibrium state, the first valve plate is spring biased against the valve body in the direction of the first chamber to seal off any flow through the valve. The second valve plate is separately spring biased against the first valve plate in the direction of the second chamber, scaling off flow between the valve plates. When the pressure of the first chamber is greater than the pressure of the second chamber by a pre-determined amount, the first and second valve plates move away from the valve body permitting fluid flow from the first chamber to the second chamber.

  9. Dual valve plate two-way pressure relief valve

    NASA Astrophysics Data System (ADS)

    Angeli, Robert J.

    1993-02-01

    This patent application discloses a two-way valve which includes dual valve plates to be positioned between first and second chambers having varying pressure therein, to relieve excess pressure in either chamber by permitting fluid flow from one chamber to the other. The valve includes a body portion having disposed therein dual valve plates. In the equilibrium state, the first valve plate is spring biased against the valve body in the direction of the first chamber to seal off any flow through the valve. The second valve plate is separately spring biased against the first valve plate in the direction of the second chamber, sealing off flow between the valve plates. When the pressure of the first chamber is greater than the pressure of the second chamber by a predetermined amount, the first and second valve plates move away from the valve body permitting fluid flow from the first chamber to the second chamber. When the pressure of the second chamber exerted on the second valve plate through apertures in the first valve plate is greater than the pressure of the first chamber by a predetermined amount, the second valve plate moves away from the face of the first valve plate permitting fluid flow from the second chamber to the first chamber.

  10. 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... FOR TANK 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...

  11. 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 §...

  12. 49 CFR 179.220-24 - Tests of pressure relief valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... pressure relief valves. Each safety relief valve must be tested by air or gas for compliance with § 179.15... 49 Transportation 3 2011-10-01 2011-10-01 false Tests of pressure relief valves. 179.220-24 Section 179.220-24 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE...

  13. 49 CFR 179.220-24 - Tests of pressure relief valves.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Tests of pressure relief valves. 179.220-24 Section 179.220-24 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND... pressure relief valves. Each safety relief valve must be tested by air or gas for compliance with §...

  14. 49 CFR 179.220-24 - Tests of pressure relief valves.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Tests of pressure relief valves. 179.220-24 Section 179.220-24 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND... pressure relief valves. Each safety relief valve must be tested by air or gas for compliance with §...

  15. 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....

  16. 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....

  17. 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....

  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 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....

  20. 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... FOR TANK 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...

  1. 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...

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. 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...

  7. 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...

  8. 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...-113 and 107A) § 179.400-21 Test of pressure relief valves. Each valve must be tested with air or...

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

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 107A) § 179.400-21 Test of pressure relief valves. Each valve must be tested with air or gas for... 49 Transportation 3 2011-10-01 2011-10-01 false Test of pressure relief valves. 179.400-21 Section 179.400-21 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE...

  10. 49 CFR 179.200-23 - Tests of pressure relief valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... pressure relief valves. (a) Each valve shall be tested by air or gas for compliance with § 179.15 before... 49 Transportation 3 2011-10-01 2011-10-01 false Tests of pressure relief valves. 179.200-23 Section 179.200-23 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE...

  11. 49 CFR 179.400-21 - Test of pressure relief valves.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 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...

  12. 49 CFR 179.200-23 - Tests of pressure relief valves.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Tests of pressure relief valves. 179.200-23 Section 179.200-23 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND... pressure relief valves. (a) Each valve shall be tested by air or gas for compliance with § 179.15...

  13. 49 CFR 179.200-23 - Tests of pressure relief valves.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Tests of pressure relief valves. 179.200-23 Section 179.200-23 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND... pressure relief valves. (a) Each valve shall be tested by air or gas for compliance with § 179.15...

  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. Force Augmentation for Relief Valve

    NASA Technical Reports Server (NTRS)

    Luger, J.

    1982-01-01

    Simple design change for poppet relief valve enables flow through valve to exert additional force to help keep valve open. Although originally intended for relief valves for liquid oxygen and liquid nitrogen in Space Shuttle orbiter, concept is applicable to pressure-or flow-actuated valves for wide range of fluids and temperatures.

  16. Numerical investigation on cavitation in pressure relief valve for coal liquefaction

    NASA Astrophysics Data System (ADS)

    Ou, G. F.; Li, W. Z.; Xiao, D. H.; Zheng, Z. J.; Dou, H. S.; Wang, C.

    2015-01-01

    The pressure relief valve for regulating the level of the high-pressure separator works under a pressure difference up to 15 MPa in the temperature of 415 °C. Severe cavitation erosion and particle impact lead to the valve disc's mass loss. In this paper, three-dimensional turbulent cavitating flows in the pressure relief valve are numerically simulated to reveal the mechanism of mass loss at valve disc. The RNG k-epsilon turbulence model and the mixture model with a mass transfer for cavitation are employed to simulate the cavitating flow in the pressure relief valve. The result shows that there is phase change in the pressure relief process and cavitation bubbles would be transported by high-velocity backflow to the head of valve disc. For the local pressure higher than the saturated vapor pressure, the bubbles collapse at the head of disc and cavitation erosion is formed at the head of the disc. By comparing the cases of opening of 40%, 50%, and 60%, backflow velocity and cavitation region in front of the disc decrease with the opening increase. Therefore, during the actual operation, the pressure relief valve should be kept to a relatively large opening.

  17. 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.

  18. 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.

  19. Sensitive low-pressure relief valve has positive seating against leakage

    NASA Technical Reports Server (NTRS)

    1964-01-01

    A pilot-operated relief valve which provides positive seating against leakage in cryogenic systems is described. The principal advantage is that the pilot poppet is unaffected by variations in control pressures in the pilot cavity, and results in a more accurate sensing of inlet pressure conditions.

  20. 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.

  1. Navier-Stokes flow field analysis of compressible flow in a pressure relief valve

    NASA Astrophysics Data System (ADS)

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

    1993-07-01

    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.

  2. 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

    ..., and agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and..., valves, connectors, and agitators in heavy liquid service; pressure relief devices in light liquid...

  3. 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

    ..., and agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and..., valves, connectors, and agitators in heavy liquid service; pressure relief devices in light liquid...

  4. 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

    ..., and agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and..., valves, connectors, and agitators in heavy liquid service; pressure relief devices in light liquid...

  5. 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

    ..., and agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and..., valves, connectors, and agitators in heavy liquid service; pressure relief devices in light liquid...

  6. 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

    ..., and agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and..., valves, connectors, and agitators in heavy liquid service; pressure relief devices in light liquid...

  7. 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

    ... liquid service, pressure relief devices in light liquid or heavy liquid service, and flanges and other... heavy liquid service, pressure relief devices in light liquid or heavy liquid service, and flanges and other connectors. (a) Pumps and valves in heavy liquid service, pressure relief devices in light...

  8. 49 CFR 178.337-9 - Pressure relief devices, piping, valves, hoses, and fittings.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Pressure relief devices, piping, valves, hoses, and fittings. 178.337-9 Section 178.337-9 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR...

  9. 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.

  10. 49 CFR 230.49 - Setting of safety relief valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... safety relief valve shall be set to open at a pressure not exceeding the MAWP. Safety relief valves shall... glass. (d) Labeling of lowest set pressure. The set pressure of the lowest safety relief valve shall be... 49 Transportation 4 2011-10-01 2011-10-01 false Setting of safety relief valves. 230.49...

  11. 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.

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. 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...

  17. Design of Pressure Relief Valves for Protection of Steel-Lined Pressure Shafts and Tunnels Against Buckling During Emptying

    NASA Astrophysics Data System (ADS)

    Schleiss, Anton J.; Manso, Pedro A.

    2012-01-01

    Using high-strength steels for pressure shafts and tunnel liners and taking into account significant rock mass participation allows the design of comparatively thin steel liners in hydropower projects. Nevertheless, during emptying of waterways, these steel linings may be endangered by buckling. Compared with traditional measures such as increased steel liner thickness and stiffeners, pressure relief valves are a very economical solution for protection of steel liners against critical external pressure and therefore buckling during emptying. A calculation procedure has been developed for the design of the required number and arrangement of pressure relief valves, and this has been used successfully in practice. Systematic model tests enabled the assumptions of the design method to be verified.

  18. 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.

  19. 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.

  20. 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

  1. 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.

  2. Development of a variable quench pressure relief valve for superconducting magnet system

    NASA Astrophysics Data System (ADS)

    Kimura, N.; Ohhata, H.; Okamura, T.; Makida, Y.; Yoshida, H.

    2011-08-01

    A new variable quench pressure relief valve (VQRV) for a superconducting magnet system has been developed at the High Energy Accelerator Research Organization (KEK). The VQRV is designed that the setting of the blowout pressure can be freely controlled and be maintenance-free for long-term operation. A prototype VQRV was tested under a high radiation environment up to 2.5 MGy. The heat load of 1.5 W at 4.2 K and a seat leakage rate of 4.5 × 10-7 kg/s at 4.2 K of the VQRV were confirmed. It has enough performances for the cryogenic system operation in the Japan Proton Accelerator Research Complex (J-PARC) neutrino beam line. The design and test results of the VQRV are described in this technical note.

  3. Relief Valve Opens And Closes Quickly

    NASA Technical Reports Server (NTRS)

    Svejkovsky, Paul A.

    1988-01-01

    Relief valve opens quickly to relieve excess pressure and closes quickly when pressure drops slightly below relief pressure. O-ring exposes one or more ports under high pressure, releasing excess pressurized fluid. Adjusting screw used to change compression on Belleville-spring washers and to set pressure at which valve opens. Designed for use aboard Space Shuttle to vent pressurized hydrazine to vacuum, valve concept useful in industrial applications where rapid opening, rapid closing, or low susceptibility to blockage by vented fluid required.

  4. 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.

  5. 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.

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

    DOE PAGESBeta

    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 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

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. 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...

  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

    ... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Pumps, valves, connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation systems standards. 63.1010 Section 63.1010 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL...

  13. 46 CFR 154.519 - Piping relief valves.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Piping relief valves. 154.519 Section 154.519 Shipping... Process Piping Systems § 154.519 Piping relief valves. (a) The liquid relief valve that protects the cargo piping system from liquid pressure exceeding the design pressure must discharge into: (1) A cargo...

  14. 46 CFR 154.519 - Piping relief valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Piping relief valves. 154.519 Section 154.519 Shipping... Process Piping Systems § 154.519 Piping relief valves. (a) The liquid relief valve that protects the cargo piping system from liquid pressure exceeding the design pressure must discharge into: (1) A cargo...

  15. 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. PMID:26944456

  16. 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?

  17. Preliminary planning study for safety relief valve experiments in a Mark III BWR pressure suppression system

    SciTech Connect

    McCauley, E.W.; Holman, G.S.

    1980-04-21

    In response to a request from the Water Reactor Safety Research Division of the US NRC, a preliminary study is provided which identifies key features and consideration involved in planning a comprehensive in-plant Safety Relief Valve experimental program for a Mark III containment design. The report provides identification of program objectives, measurement system requirements, and some details quantifying expected system response. In addition, a preliminary test matrix is outlined which involves a supporting philosophy intended to enhance the usefulness of the experimental results for all members of the program team: experimentalists, analysts, and plant operator.

  18. 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.

  19. 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.

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

    NASA Astrophysics Data System (ADS)

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

    1993-12-01

    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.

  1. 46 CFR 54.15-10 - Safety and relief valves (modifies UG-126).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 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... marked. (h) The rated relieving capacity of safety and relief valves for use on pressure vessels shall...

  2. 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.

  3. 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.

  4. 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

    ... agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation systems..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and... in heavy liquid service; pressure relief devices in light liquid or heavy liquid service;...

  5. 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

    ... agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation systems..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and... in heavy liquid service; pressure relief devices in light liquid or heavy liquid service;...

  6. 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

    ... agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation systems..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and... in heavy liquid service; pressure relief devices in light liquid or heavy liquid service;...

  7. 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

    ... agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation systems..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and... heavy liquid service; pressure relief devices in light liquid or heavy liquid service;...

  8. 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

    ... agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation systems..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and... heavy liquid service; pressure relief devices in light liquid or heavy liquid service;...

  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..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and... heavy liquid service; pressure relief devices in light liquid or heavy liquid service;...

  10. 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

    ... agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation systems..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and... in heavy liquid service; pressure relief devices in light liquid or heavy liquid service;...

  11. 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..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and... in heavy liquid service; pressure relief devices in light liquid or heavy liquid service;...

  12. 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

    ... agitators in heavy liquid service; pressure relief devices in liquid service; and instrumentation systems..., connectors, and agitators in heavy liquid service; pressure relief devices in liquid service; and... heavy liquid service; pressure relief devices in light liquid or heavy liquid service;...

  13. Integral valve provides automatic relief and remote venting

    NASA Technical Reports Server (NTRS)

    Gilmore, R. F.

    1969-01-01

    In-line, pilot-operated, differential area, poppet type valve provides both automatic relief of a tank at a precise over-pressure and remote control of tank venting. Relief and vent operations are separate functions incorporated in an integral valve package.

  14. 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.

  15. 49 CFR 178.338-8 - Pressure relief devices, piping, valves, and fittings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) Pipe joints must be threaded, welded or flanged. If threaded pipe is used, the pipe and fittings must... connection to that coil must be provided with a valve or check valve as close to the tank shell as practicable to prevent the loss of vapor from the tank in case of damage to the coil. The liquid connection...

  16. Damage-Free Relief-Valve Disassembly

    NASA Technical Reports Server (NTRS)

    Haselmaier, H.

    1986-01-01

    Tool safely disassembles relief valves without damage to sensitive parts. Relief-valve disassembly tool used to extract valve nozzle from its housing. Holding device on tool grops nozzle. When user strikes hammer against impact disk, holding device pulls nozzle from press fit. Previously, nozzle dislodged by striking spindle above it, but practice often damaged retaining screw. New tool removes nozzle directly. With minor modifications, tool adapted to valves from different manufacturers.

  17. 49 CFR 178.338-8 - Pressure relief devices, piping, valves, and fittings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... leakage when connected. (4) Piping must be protected from damage due to thermal expansion and contraction... 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....

  18. 49 CFR 178.338-8 - Pressure relief devices, piping, valves, and fittings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... leakage when connected. (4) Piping must be protected from damage due to thermal expansion and contraction... 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....

  19. 49 CFR 178.338-8 - Pressure relief devices, piping, valves, and fittings.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... leakage when connected. (4) Piping must be protected from damage due to thermal expansion and contraction... 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....

  20. 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.

  1. Inexpensive tamper proof safety relief valve

    NASA Technical Reports Server (NTRS)

    Frankewich, P. A.

    1970-01-01

    Basic relief valve has added safety relief valve capability that relieves overpressure before failure can occur. It may be installed in inaccesible areas with a high degree of reliability, constructed from a variety of materials, and adapted to the user's specific application.

  2. 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...

  3. 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...

  4. 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... Process Piping Systems § 154.519 Piping relief valves. (a) The liquid relief valve that protects the cargo... cargo that is specially approved by the Commandant (CG-ENG). (b) A relief valve on a cargo pump...

  5. 46 CFR 154.519 - Piping relief valves.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Piping relief valves. 154.519 Section 154.519 Shipping... Process Piping Systems § 154.519 Piping relief valves. (a) The liquid relief valve that protects the cargo... cargo that is specially approved by the Commandant (CG-ENG). (b) A relief valve on a cargo pump...

  6. 46 CFR 154.519 - Piping relief valves.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Piping relief valves. 154.519 Section 154.519 Shipping... Process Piping Systems § 154.519 Piping relief valves. (a) The liquid relief valve that protects the cargo... cargo that is specially approved by the Commandant (CG-ENG). (b) A relief valve on a cargo pump...

  7. 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...

  8. Mechanism of noise generation by cavitation in hydraulic relief valve

    NASA Astrophysics Data System (ADS)

    Okita, K.; Miyamoto, Y.; Kataoka, T.; Takagi, S.; Kato, H.

    2015-12-01

    In order to clarify the mechanism of noise generation in a hydraulic relief valve, oil cavitating flows in a half cut model of the valve were observed by means of a high-speed camera and were simulated numerically. As the result of image analysis, the fluctuation of cavitation volume is corresponding to the pressure fluctuation of downstream, and the both fluctuations take peaks at frequencies from 1.5 to 2.5 kHz depending on the back pressure. In addition, as the back pressure increases, the frequency of the pressure fluctuation increases and the peak value decreases. These phenomena were also qualitatively reproduced in the numerical simulation.

  9. 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

  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 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)....

  12. 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)....

  13. 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.

  14. 49 CFR 179.500-16 - Tests of pressure relief devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Tests of pressure relief devices. 179.500-16...-113 and 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...

  15. 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...

  16. 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...

  17. 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...

  18. 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...

  19. 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...

  20. 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...

  1. 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...

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. The bombardier beetle and its use of a pressure relief valve system to deliver a periodic pulsed spray.

    PubMed

    Beheshti, Novid; Mcintosh, Andy C

    2007-12-01

    In this paper the combustion chamber of the bombardier beetle is considered and recent findings are presented which demonstrate that certain parts of the anatomy are in fact inlet and outlet valves. In particular, the authors show that the intake and exhaust valve mechanism involves a repeated (pulsating) steam explosion, the principle of which was up till now unclear. New research here has now shown the characteristics of the ejections and the role of important valves. In this paper numerical simulations of the two-phase flow ejection are presented which demonstrate that the principle of cyclic water injection followed by water and steam decompression explosions is the fundamental mechanism used to create the repeated ejections. PMID:18037729

  7. 46 CFR 154.801 - Pressure relief systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 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...

  8. 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...

  9. 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...

  10. 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...

  11. Specifications and Performances of Series Superfluid Helium Safety Relief Valves for the LHC

    NASA Astrophysics Data System (ADS)

    Perin, A.; Fontanive, V.

    2006-04-01

    Protecting the LHC magnets requires safety relief valves operating with 1.9 K pressurized superfluid helium at their inlet. Following the evaluation of prototype valves, a specification for the production of the 360 safety relief valves needed for the LHC was issued. The production of the safety valves was then awarded to an industrial contractor. The performances of pre-series valves were assessed for a variety of aspects including thermal performance, leak tightness in superfluid helium, dynamic behavior and resistance to intensive mechanical cycling. After the initial validation phase the series production was completed within the technical requirements of the specification. This paper describes the characteristics of the safety relief valves and the specifications for their industrial production. The performances of the pre-series valves are presented and an overview of the series production phase is given.

  12. 49 CFR 179.15 - Pressure relief devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... equal to the sum of the static head and gas padding pressure and the lading vapor pressure at the.... (3) The vapor tight pressure of a reclosing pressure relief valve must be at least 80 percent of the... indicator. The detection device must be closed during transportation. (3) The vapor tight pressure and...

  13. Efficiently evaluate complex pressure relief systems

    SciTech Connect

    Wright, R.K.; Walker, A.G.

    1997-01-01

    This article will present the steps necessary to perform a comprehensive analysis of complex pressure relief systems. The goal is not to discuss detailed calculations for proper valve sizing and selection, but rather to analyze and verify existing system configurations. Sizing and selection have been covered in detail by the American Petroleum Institute (API) RP 520, API RP 521, various AIChE Design Institute for Emergency Relief Systems (DIERS) publications, and other sources. In their work with industry, the authors have noticed a tendency for some engineers to proceed with detailed calculations without first preparing an overall strategy and implementation plan to make sure that the calculations yield the desired results. They have seen detailed pressure relief system analyses costing hundreds of thousands of dollars which, for any number of reasons, are incorrect. The old adage GIGO (garbage in/garbage out) certainly applies to pressure relief system analysis. They will address the thought processes and actions necessary to correctly and efficiently evaluate complex pressure relief systems.

  14. 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...

  15. 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...

  16. 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...

  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. 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...

  19. 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

  20. Cryostat "UV" Relief Valve Selection and Process Flow

    SciTech Connect

    Mulholland, G.T.; Wintercorn, S.J.; /Fermilab

    1987-08-11

    This report describes the selection of the relief valves for the D-Zero cryostats. The selection was based on the flow requirements calculated in D-Zero engineering note 3740.214,224-EN-6 under fire conditions (1200 F, no vacuum) for the central cryostat; 264 SCFM. This value was calculated from section 5.3.5 of 'Pressure Relief Device Standards; S 1.3-Compressed Gas Storage Containers', published by the Compressed Gas Association, Inc. The flow calculated above is far greater than the required fire condition flow capacity of 264 SCFM. The improbable 70 F flow temperature value of 738 SCFM is still much greater than the required fire capacity. The flow capacity of the paralleled supplemental rupture disc is 2640 SCFM, independently greater than the fire condition flow requirement.

  1. 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

  2. 49 CFR 192.199 - Requirements for design of pressure relief and limiting devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... pressure relief valve or pressure limiting device inoperative. ... 49 Transportation 3 2011-10-01 2011-10-01 false Requirements for design of pressure relief and... Design of Pipeline Components § 192.199 Requirements for design of pressure relief and limiting...

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

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Tests of pressure relief devices. 179.300-17... Tests of 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)...

  5. 46 CFR 38.10-15 - Safety relief valves-TB/ALL.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (Specifications) of this chapter may be used on tanks for a maximum pressure of 10 pounds per square inch gage... be used for any pressure. (c) The safety relief valves shall have a combined relieving capacity to discharge the greater of the following with not more than 20 percent rise in pressure (in the tank)...

  6. 46 CFR 38.10-15 - Safety relief valves-TB/ALL.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (Specifications) of this chapter may be used on tanks for a maximum pressure of 10 pounds per square inch gage... be used for any pressure. (c) The safety relief valves shall have a combined relieving capacity to discharge the greater of the following with not more than 20 percent rise in pressure (in the tank)...

  7. Argon Dewar Relief Set Pressure Modifications

    SciTech Connect

    Wu, J.; /Fermilab

    1991-03-19

    This engineering note documents the calculations of Kelly Dixon, used to determine the maximum allowable set pressure for the argon dewar low relief valve, tag number PSV620A, Anderson Greenwood Type 526J. The original setting was 16 psig. This value was chosen in order to protect against cryostat overpressurization by the source dewar (see D0 Engineering Note 115), however, the following calculations will show that the set pressure can be raised to approximately 18.5 psig, which would result in a faster filling of the cryostat, along with a higher level of liquid argon. Three other engineering notes were revised to reflect the change in set pressure according to this note. They are notes 115, 219, and 263.

  8. 46 CFR 54.15-10 - Safety and relief valves (modifies UG-126).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... reference; see 46 CFR 54.01-1). (f) Cast iron may be employed in the construction of relief valves for... with CGA S-1.2 (incorporated by reference; see 46 CFR 54.01-1). (2) 110 percent of the valve set... relief valves shall be of the direct spring loaded type. (c) Safety and relief valves for steam or...

  9. 46 CFR 54.15-10 - Safety and relief valves (modifies UG-126).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... reference; see 46 CFR 54.01-1). (f) Cast iron may be employed in the construction of relief valves for... with CGA S-1.2 (incorporated by reference; see 46 CFR 54.01-1). (2) 110 percent of the valve set... relief valves shall be of the direct spring loaded type. (c) Safety and relief valves for steam or...

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

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 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... 46 Shipping 1 2011-10-01 2011-10-01 false Safety relief valves-TB/ALL. 38.25-10 Section...

  11. Pressure relief subsystem design description

    SciTech Connect

    1986-07-01

    The primary function of the Pressure Relief Subsystem, a subsystem of the Vessel System, is to provide overpressure protection to the Vessel System. When the overpressure setpoint is reached, pressure is reduced by permitting the flow of primary coolant out of the Vessel System. This subsystem also provides the flow path by which purified helium is returned to the vessel system, either as circulating purge/flow from the Helium Purification Subsystem or make-up helium from the Helium Storage and Transfer Subsystem.

  12. 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.

  13. 49 CFR 179.100-19 - Tests of safety relief valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Tests of safety relief valves. 179.100-19 Section... HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR TANK CARS Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120) §...

  14. 49 CFR 179.100-19 - Tests of safety relief valves.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Tests of safety relief valves. 179.100-19 Section... HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR TANK CARS Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120) §...

  15. 49 CFR 179.100-19 - Tests of safety relief valves.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Tests of safety relief valves. 179.100-19 Section... HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR TANK CARS Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and 120) §...

  16. 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... MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS SPECIFICATIONS FOR TANK CARS Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and...

  17. 123. View in subway of relief and safety valves for ...

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

    123. View in subway of relief and safety valves for turbine unit no. 3; looking northeast. To right is entrance to Basement Room B-4. Photo by Jet Lowe, HAER, 1989. - Puget Sound Power & Light Company, White River Hydroelectric Project, 600 North River Avenue, Dieringer, Pierce County, WA

  18. 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...

  19. 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...

  20. 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...

  1. 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...

  2. 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...

  3. 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.

  4. 33 CFR 149.105 - What are the requirements for the overflow and relief valves?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) Each oil and natural gas transfer system (OTS/NGTS) must include a relief valve that, when activated... transfer system overflow or relief valve must not allow a discharge into the sea. ... overflow and relief valves? 149.105 Section 149.105 Navigation and Navigable Waters COAST GUARD,...

  5. 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...

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. 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

    ... (incorporated by reference; see 46 CFR 53.01-1) except as noted otherwise in this section. (b) Hot water heating... 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...

  11. 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

    ... (incorporated by reference; see 46 CFR 53.01-1) except as noted otherwise in this section. (b) Hot water heating... 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...

  12. 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

    ... (incorporated by reference; see 46 CFR 53.01-1) except as noted otherwise in this section. (b) Hot water heating... 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...

  13. 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

    ... (incorporated by reference; see 46 CFR 53.01-1) except as noted otherwise in this section. (b) Hot water heating... 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...

  14. 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

    ... (incorporated by reference; see 46 CFR 53.01-1) except as noted otherwise in this section. (b) Hot water heating... 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...

  15. 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.

  16. High pressure gate valve failure

    SciTech Connect

    Place, M. Jr.; Kochera, J.W.

    1995-10-01

    Shell Oil Company was attempting to develop CRA (Corrosion Resistant Alloy) valves for use in those completions utilizing CRA tubing. The testing and development of new materials for CRA valves of both the solid and clad version were pursued. As part of this CRA valve development program, Shell Oil Company tried to reconcile the apparent discrepancy between unacceptable laboratory test results on 410 SS in sour environments with both the apparent success (when properly heat treated and at an acceptable hardness level) of this alloy in commercial sour use and the fact that it is fully accepted in NACE MR-01-75. A410 stainless steel valve was tested near the material yield strength at low H{sub 2}S partial pressures at the STF (Static Test Facility) in Mississippi. The valve failed by crack growth and body wall leakage while under test.

  17. Pressure valve for needle gate valve control. June 13, 1913. ...

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

    Pressure valve for needle gate valve control. June 13, 1913. Photocopy of original drawing. Drawing on file at the Salt River Project Archives. Phoenix, Arizona - Cross Cut Hydro Plant, North Side of Salt River, Tempe, Maricopa County, AZ

  18. 49 CFR 179.100-19 - Tests of safety relief valves.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Tests of safety relief valves. 179.100-19 Section 179.100-19 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND... Tests of safety relief valves. (a) Each valve shall be tested by air or gas for compliance with §...

  19. 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..., Fittings, and Accessory Equipment § 38.10-15 Safety relief valves—TB/ALL. (a) Each tank shall be fitted with or (subject to approval by the Commandant) connected to one or more safety relief valves...

  20. 46 CFR 64.71 - Marking of pressure relief devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Marking of pressure relief devices. 64.71 Section 64.71... AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.71 Marking of pressure relief devices. A pressure relief device must be plainly and permanently marked with...

  1. 46 CFR 64.57 - Acceptance of pressure relief devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Acceptance of pressure relief devices. 64.57 Section 64... PORTABLE TANKS AND CARGO HANDLING SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.57 Acceptance of pressure relief devices. A pressure relief device for an MPT must be— (a) From...

  2. LOX, GOX and Pressure Relief

    NASA Technical Reports Server (NTRS)

    McLeod, Ken; Stoltzfus, Joel

    2006-01-01

    Oxygen relief systems present a serious fire hazard risk with often severe consequences. This presentation offers a risk management solution strategy which encourages minimizing ignition hazards, maximizing best materials, and utilizing good practices. Additionally, the relief system should be designed for cleanability and ballistic flow. The use of the right metals, softgoods, and lubricants, along with the best assembly techniques, is stressed. Materials should also be tested if data is not available and a full hazard analysis should be conducted in an effort to minimize risk and harm.

  3. Conceptual design of pressure relief systems for cryogenic application

    NASA Astrophysics Data System (ADS)

    Grohmann, S.; Süßer, M.

    2014-01-01

    The conceptual design of pressure relief systems is an important aspect in the early phase of any cryogenic system design, because a prudent and responsible evaluation of relief systems involves much more than just relief devices. The conceptual design consists of various steps: At first, hazard scenarios must be considered and the worst-case scenario identified. Next, a staged interaction against pressure increase is to be defined. This is followed by the selection of the general type of pressure relief device for each stage, such as safety valve and rupture disc, respectively. Then, a decision concerning their locations, their capacities and specific features must be taken. Furthermore, it is mandatory to consider the inlet pressure drop and the back pressure in the exhaust line for sizing the safety devices. And last but not least, economic and environmental considerations must be made in case of releasing the medium to the atmosphere. The development of the system's safety concept calls for a risk management strategy based on identification and analysis of hazards, and consequent risk mitigation using a system-based approach in compliance with the standards.

  4. Conceptual design of pressure relief systems for cryogenic application

    SciTech Connect

    Grohmann, S.; Süßer, M.

    2014-01-29

    The conceptual design of pressure relief systems is an important aspect in the early phase of any cryogenic system design, because a prudent and responsible evaluation of relief systems involves much more than just relief devices. The conceptual design consists of various steps: At first, hazard scenarios must be considered and the worst-case scenario identified. Next, a staged interaction against pressure increase is to be defined. This is followed by the selection of the general type of pressure relief device for each stage, such as safety valve and rupture disc, respectively. Then, a decision concerning their locations, their capacities and specific features must be taken. Furthermore, it is mandatory to consider the inlet pressure drop and the back pressure in the exhaust line for sizing the safety devices. And last but not least, economic and environmental considerations must be made in case of releasing the medium to the atmosphere. The development of the system's safety concept calls for a risk management strategy based on identification and analysis of hazards, and consequent risk mitigation using a system-based approach in compliance with the standards.

  5. Low energy high pressure miniature screw valve

    DOEpatents

    Fischer, Gary J.; Spletzer, Barry L.

    2006-12-12

    A low energy high pressure screw valve having a valve body having an upper portion and a lower portion, said lower portion of said valve body defining an inlet flow passage and an outlet flow passage traversing said valve body to a valve seat, said upper portion of said valve body defining a cavity at said valve seat, a diaphragm restricting flow between said upper portion of said valve body and said lower portion, said diaphragm capable of engaging said valve seat to restrict fluid communication between said inlet passage and said outlet passage, a plunger within said cavity supporting said diaphragm, said plunger being capable of engaging said diaphragm with said valve seat at said inlet and outlet fluid passages, said plunger being in point contact with a drive screw having threads engaged with opposing threads within said upper portion of said valve body such engagement allowing motion of said drive screw within said valve body.

  6. 49 CFR 179.400-20 - Pressure relief devices.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Pressure relief devices. 179.400-20 Section 179...-20 Pressure relief devices. (a) The tank must be provided with pressure relief devices for the... safety appliances. Vent or weep holes in pressure relief devices are prohibited. All main pressure...

  7. 49 CFR 179.400-20 - Pressure relief devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Pressure relief devices. 179.400-20 Section 179...-20 Pressure relief devices. (a) The tank must be provided with pressure relief devices for the... safety appliances. Vent or weep holes in pressure relief devices are prohibited. All main pressure...

  8. 49 CFR 179.400-20 - Pressure relief devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Pressure relief devices. 179.400-20 Section 179...-20 Pressure relief devices. (a) The tank must be provided with pressure relief devices for the... safety appliances. Vent or weep holes in pressure relief devices are prohibited. All main pressure...

  9. 49 CFR 179.400-20 - Pressure relief devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Pressure relief devices. 179.400-20 Section 179... and 107A) § 179.400-20 Pressure relief devices. (a) The tank must be provided with pressure relief... structure, trucks and safety appliances. Vent or weep holes in pressure relief devices are prohibited....

  10. 46 CFR 38.10-15 - Safety relief valves-TB/ALL.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 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...

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. FLUID PRESSURE AND CAM OPERATED VACUUM VALVE

    DOEpatents

    Batzer, T.H.

    1963-11-26

    An ultra-high vacuum valve that is bakable, reusable, and capable of being quickly opened and closed is described. A translationally movable valve gate having an annular ridge is adapted to contact an annular soft metal gasket disposed at the valve seat such that the soft metal gasket extends beyond the annular ridge on all sides. The valve gate is closed, by first laterally aligning the valve gate with the valve seat and then bringing the valve gate and valve seat into seating contact by the translational movement of a ramp-like wedging means that engages similar ramp-like stractures at the base of the valve gate to force the valve gate into essentially pressureless contact with the annular soft metal gasket. This gasket is then pressurized from beneath by a fluid thereby effecting a vacuura tight seal between the gasket and the ridge. (AEC)

  17. Pressure compensated flow control valve

    DOEpatents

    Minteer, Daniel J.

    1999-01-01

    The invention is an air flow control valve which is capable of maintaining a constant flow at the outlet despite changes in the inlet or outlet pressure. The device consists of a shell assembly with an inlet chamber and outlet chamber separated by a separation plate. The chambers are connected by an orifice. Also located within the inlet chamber is a port controller assembly. The port controller assembly consists of a differential pressure plate and port cap affixed thereon. The cap is able to slide in and out of the orifice separating the inlet and outlet chambers. When the pressure differential is sufficient, the differential pressure plate rises or falls to maintain a constant air flow. Movement of the port controller assembly does not require the use of seals, diaphragms, tight tolerances, bushings, bearings, hinges, guides, or lubricants.

  18. 46 CFR 38.25-10 - Safety relief valves-TB/ALL.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 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 shall be inspected at least once in every...

  19. 46 CFR 38.25-10 - 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. 38.25-10 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 shall be inspected at least once in every...

  20. 46 CFR 38.25-10 - Safety relief valves-TB/ALL.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 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 shall be inspected at least once in every...

  1. 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 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 shall be inspected at least once in every...

  2. 49 CFR 179.500-12 - Pressure relief devices.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Pressure relief devices. 179.500-12 Section 179...-12 Pressure relief devices. (a) Tank shall be equipped with one or more pressure relief devices of... pressure equal to 70 percent of the marked test pressure of tank, flow capacity will be sufficient...

  3. 49 CFR 179.500-12 - Pressure relief devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Pressure relief devices. 179.500-12 Section 179...-12 Pressure relief devices. (a) Tank shall be equipped with one or more pressure relief devices of... pressure equal to 70 percent of the marked test pressure of tank, flow capacity will be sufficient...

  4. 49 CFR 179.500-12 - Pressure relief devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Pressure relief devices. 179.500-12 Section 179...-12 Pressure relief devices. (a) Tank shall be equipped with one or more pressure relief devices of... pressure equal to 70 percent of the marked test pressure of tank, flow capacity will be sufficient...

  5. 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

    ... reference; see 46 CFR 52.01-1) except as noted otherwise in this section. (2) A safety valve must: (i) Be... (CONTINUED) MARINE ENGINEERING POWER BOILERS General Requirements § 52.01-120 Safety valves and safety relief... than 51mm (2 in.) NPS. (3) On river steam vessels whose boilers are connected in batteries...

  6. 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

    ... reference; see 46 CFR 52.01-1) except as noted otherwise in this section. (2) A safety valve must: (i) Be... (CONTINUED) MARINE ENGINEERING POWER BOILERS General Requirements § 52.01-120 Safety valves and safety relief... than 51mm (2 in.) NPS. (3) On river steam vessels whose boilers are connected in batteries...

  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

    ... reference; see 46 CFR 52.01-1) except as noted otherwise in this section. (2) A safety valve must: (i) Be... (CONTINUED) MARINE ENGINEERING POWER BOILERS General Requirements § 52.01-120 Safety valves and safety relief... than 51mm (2 in.) NPS. (3) On river steam vessels whose boilers are connected in batteries...

  8. 46 CFR 153.371 - Minimum relief valve setting for refrigerated cargo tanks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... steady state temperature obtained by a full tank of cargo with the refrigeration system operating under... tanks. The relief valve setting for a containment system that carries a refrigerated cargo must at...

  9. 49 CFR 178.346-3 - Pressure relief.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Pressure relief. 178.346-3 Section 178.346-3... Containers for Motor Vehicle Transportation § 178.346-3 Pressure relief. (a) Each cargo tank must be equipped with a pressure relief system in accordance with § 178.345-10 and this section. (b) Type...

  10. 49 CFR 178.347-4 - Pressure relief.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Pressure relief. 178.347-4 Section 178.347-4... Specifications for Containers for Motor Vehicle Transportation § 178.347-4 Pressure relief. (a) Each cargo tank must be equipped with a pressure and vacuum relief system in accordance with § 178.345-10 and...

  11. 49 CFR 178.347-4 - Pressure relief.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Pressure relief. 178.347-4 Section 178.347-4... Containers for Motor Vehicle Transportation § 178.347-4 Pressure relief. (a) Each cargo tank must be equipped with a pressure and vacuum relief system in accordance with § 178.345-10 and this section. (b) Type...

  12. 49 CFR 178.347-4 - Pressure relief.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Pressure relief. 178.347-4 Section 178.347-4... Containers for Motor Vehicle Transportation § 178.347-4 Pressure relief. (a) Each cargo tank must be equipped with a pressure and vacuum relief system in accordance with § 178.345-10 and this section. (b) Type...

  13. 49 CFR 178.346-3 - Pressure relief.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Pressure relief. 178.346-3 Section 178.346-3... Containers for Motor Vehicle Transportation § 178.346-3 Pressure relief. (a) Each cargo tank must be equipped with a pressure relief system in accordance with § 178.345-10 and this section. (b) Type...

  14. 49 CFR 178.346-3 - Pressure relief.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Pressure relief. 178.346-3 Section 178.346-3... Containers for Motor Vehicle Transportation § 178.346-3 Pressure relief. (a) Each cargo tank must be equipped with a pressure relief system in accordance with § 178.345-10 and this section. (b) Type...

  15. 49 CFR 178.346-3 - Pressure relief.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Pressure relief. 178.346-3 Section 178.346-3... Containers for Motor Vehicle Transportation § 178.346-3 Pressure relief. (a) Each cargo tank must be equipped with a pressure relief system in accordance with § 178.345-10 and this section. (b) Type...

  16. 49 CFR 178.346-3 - Pressure relief.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Pressure relief. 178.346-3 Section 178.346-3... Specifications for Containers for Motor Vehicle Transportation § 178.346-3 Pressure relief. (a) Each cargo tank must be equipped with a pressure relief system in accordance with § 178.345-10 and this section....

  17. 49 CFR 178.347-4 - Pressure relief.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Pressure relief. 178.347-4 Section 178.347-4... Containers for Motor Vehicle Transportation § 178.347-4 Pressure relief. (a) Each cargo tank must be equipped with a pressure and vacuum relief system in accordance with § 178.345-10 and this section. (b) Type...

  18. 49 CFR 178.347-4 - Pressure relief.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Pressure relief. 178.347-4 Section 178.347-4... Containers for Motor Vehicle Transportation § 178.347-4 Pressure relief. (a) Each cargo tank must be equipped with a pressure and vacuum relief system in accordance with § 178.345-10 and this section. (b) Type...

  19. 46 CFR 54.15-10 - Safety and relief valves (modifies UG-126).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... reference; see 46 CFR 54.01-1). (f) Cast iron may be employed in the construction of relief valves for... with CGA S-1.2 (incorporated by reference; see 46 CFR 54.01-1). (2) 110 percent of the valve set... rated capacity if some essential part of the pilot or auxiliary device should fail. All other safety...

  20. 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

    ... reference; see 46 CFR 52.01-1) except as noted otherwise in this section. (2) A safety valve must: (i) Be... capacity certified by the National Board of Boiler and Pressure Vessel Inspectors; (iii) Have a drain... relieving capacity of drum and superheater safety valves as certified by the valve manufacturer shall not...

  1. 49 CFR 179.500-12 - Pressure relief devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Pressure relief devices. 179.500-12 Section 179... and 107A) § 179.500-12 Pressure relief devices. (a) Tank shall be equipped with one or more pressure..., with tank filled with air at pressure equal to 70 percent of the marked test pressure of tank,...

  2. 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.

  3. 46 CFR 64.71 - Marking of pressure relief devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Marking of pressure relief devices. 64.71 Section 64.71 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 § 64.71...

  4. 46 CFR 64.57 - Acceptance of pressure relief devices.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Acceptance of pressure relief devices. 64.57 Section 64.57 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 §...

  5. 46 CFR 64.71 - Marking of pressure relief devices.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Marking of pressure relief devices. 64.71 Section 64.71 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 § 64.71...

  6. 46 CFR 64.57 - Acceptance of pressure relief devices.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Acceptance of pressure relief devices. 64.57 Section 64.57 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 §...

  7. 46 CFR 64.57 - Acceptance of pressure relief devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Acceptance of pressure relief devices. 64.57 Section 64.57 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 §...

  8. 46 CFR 64.57 - Acceptance of pressure relief devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Acceptance of pressure relief devices. 64.57 Section 64.57 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 §...

  9. 46 CFR 64.71 - Marking of pressure relief devices.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Marking of pressure relief devices. 64.71 Section 64.71 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 § 64.71...

  10. 46 CFR 154.802 - Alternate pressure relief settings.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 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...) Change the set pressure without pressure testing to verify the new setting; and (2) Can be...

  11. 46 CFR 154.802 - Alternate pressure relief settings.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 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...) Change the set pressure without pressure testing to verify the new setting; and (2) Can be...

  12. 46 CFR 154.802 - Alternate pressure relief settings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 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...) Change the set pressure without pressure testing to verify the new setting; and (2) Can be...

  13. 46 CFR 154.802 - Alternate pressure relief settings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 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...) Change the set pressure without pressure testing to verify the new setting; and (2) Can be...

  14. 49 CFR 178.345-10 - Pressure relief.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Pressure relief. 178.345-10 Section 178.345-10... Containers for Motor Vehicle Transportation § 178.345-10 Pressure relief. (a) Each cargo tank must be equipped to relieve pressure and vacuum conditions in conformance with this section and the...

  15. 14 CFR 121.267 - Extinguishing agent container pressure relief.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Extinguishing agent container pressure....267 Extinguishing agent container pressure relief. Extinguishing agent containers must be provided with a pressure relief to prevent bursting of the container because of excessive internal...

  16. 49 CFR 178.345-10 - Pressure relief.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Pressure relief. 178.345-10 Section 178.345-10... Containers for Motor Vehicle Transportation § 178.345-10 Pressure relief. (a) Each cargo tank must be equipped to relieve pressure and vacuum conditions in conformance with this section and the...

  17. 49 CFR 178.345-10 - Pressure relief.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Pressure relief. 178.345-10 Section 178.345-10... Containers for Motor Vehicle Transportation § 178.345-10 Pressure relief. (a) Each cargo tank must be equipped to relieve pressure and vacuum conditions in conformance with this section and the...

  18. 49 CFR 179.300-15 - Pressure relief devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Pressure relief devices. 179.300-15 Section 179... Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A and 110AW) § 179.300-15 Pressure relief devices... shall be sufficient to prevent building up pressure in tank in excess of 82.5 percent of the tank...

  19. 49 CFR 179.300-15 - Pressure relief devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Pressure relief devices. 179.300-15 Section 179... Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A and 110AW) § 179.300-15 Pressure relief devices... shall be sufficient to prevent building up pressure in tank in excess of 82.5 percent of the tank...

  20. 49 CFR 178.345-10 - Pressure relief.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Pressure relief. 178.345-10 Section 178.345-10... Containers for Motor Vehicle Transportation § 178.345-10 Pressure relief. (a) Each cargo tank must be equipped to relieve pressure and vacuum conditions in conformance with this section and the...

  1. 49 CFR 178.345-10 - Pressure relief.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Pressure relief. 178.345-10 Section 178.345-10... Specifications for Containers for Motor Vehicle Transportation § 178.345-10 Pressure relief. (a) Each cargo tank must be equipped to relieve pressure and vacuum conditions in conformance with this section and...

  2. 14 CFR 125.165 - Extinguishing agent container pressure relief.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Extinguishing agent container pressure... Requirements § 125.165 Extinguishing agent container pressure relief. Extinguishing agent containers must be provided with a pressure relief to prevent bursting of the container because of excessive...

  3. 49 CFR 179.300-15 - Pressure relief devices.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Pressure relief devices. 179.300-15 Section 179... Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A and 110AW) § 179.300-15 Pressure relief devices... shall be sufficient to prevent building up pressure in tank in excess of 82.5 percent of the tank...

  4. 49 CFR 179.300-15 - Pressure relief devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Pressure relief devices. 179.300-15 Section 179... Pressure relief devices. (a) Unless prohibited in part 173 of this subchapter, tanks shall be equipped with... total discharge capacity shall be sufficient to prevent building up pressure in tank in excess of...

  5. [Safety of oxygen-pressure-reducing valves].

    PubMed

    Dauphin, A

    1999-11-01

    When a gas cylinder valve is opened slowly, as required, the associated pressure reducing valve works properly and gas expansion decreases the temperature of the device proportionally to the delivered gas flow. Conversely, when the valve is opened rapidly, the pressure in the high pressure chamber grows suddenly from 0 to 200 bars in the case of a full O2-cylinder, if no flow is required at the valve outlet. This adiabatic compression in a small space generates a peak of high temperature. In the presence of combustible foreign debris and O2, ignition can occur. When the melting point of the metallic component is reached the device bursts and those in the vicinity are at risk of burns or death from inhalation of melten metallic debris. As several of such critical incidents occurred with O2-pressure-reducing valves whose high pressure chambers were made of aluminium, the French medical devices agency has enacted a regulation prohibiting their use. PMID:10615550

  6. 46 CFR 95.15-40 - Pressure relief.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Pressure relief. 95.15-40 Section 95.15-40 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 95.15-40 Pressure relief. (a) Where...

  7. 46 CFR 193.15-40 - Pressure relief.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Pressure relief. 193.15-40 Section 193.15-40 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide and Clean Agent Extinguishing Systems, Details § 193.15-40 Pressure relief....

  8. 46 CFR 95.16-35 - Pressure relief.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Pressure relief. 95.16-35 Section 95.16-35 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS FIRE PROTECTION EQUIPMENT Fixed Clean Agent Gas Extinguishing Systems, Details § 95.16-35 Pressure relief....

  9. 46 CFR 95.15-40 - Pressure relief.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Pressure relief. 95.15-40 Section 95.15-40 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 95.15-40 Pressure relief. (a) Where...

  10. 46 CFR 95.16-35 - Pressure relief.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Pressure relief. 95.16-35 Section 95.16-35 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS FIRE PROTECTION EQUIPMENT Fixed Clean Agent Gas Extinguishing Systems, Details § 95.16-35 Pressure relief....

  11. 46 CFR 95.16-35 - Pressure relief.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Pressure relief. 95.16-35 Section 95.16-35 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS FIRE PROTECTION EQUIPMENT Fixed Clean Agent Gas Extinguishing Systems, Details § 95.16-35 Pressure relief....

  12. 46 CFR 193.15-40 - Pressure relief.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Pressure relief. 193.15-40 Section 193.15-40 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide and Clean Agent Extinguishing Systems, Details § 193.15-40 Pressure relief. (a) Where necessary, relatively...

  13. 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... remove liquid cargo....

  14. 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... remove liquid cargo....

  15. 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....

  16. 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... remove liquid cargo....

  17. 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... remove liquid cargo....

  18. 46 CFR 193.15-40 - Pressure relief.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Pressure relief. 193.15-40 Section 193.15-40 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide and Clean Agent Extinguishing Systems, Details § 193.15-40 Pressure relief. (a) Where necessary, relatively...

  19. 46 CFR 95.15-40 - Pressure relief.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Pressure relief. 95.15-40 Section 95.15-40 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS FIRE PROTECTION EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 95.15-40 Pressure relief. (a) Where necessary, relatively tight compartments such...

  20. 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.

  1. 46 CFR 193.15-40 - Pressure relief.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 193.15-40 Pressure relief. (a) Where necessary... suitable means for relieving excessive pressure accumulating within the compartment when the carbon...

  2. 46 CFR 76.15-40 - Pressure relief.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Carbon Dioxide Extinguishing Systems, Details § 76.15-40 Pressure relief. (a) Where necessary, relatively... means for relieving excessive pressure accumulating within the compartment when the carbon dioxide...

  3. 46 CFR 76.15-40 - Pressure relief.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Carbon Dioxide Extinguishing Systems, Details § 76.15-40 Pressure relief. (a) Where necessary, relatively... means for relieving excessive pressure accumulating within the compartment when the carbon dioxide...

  4. 46 CFR 193.15-40 - Pressure relief.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 193.15-40 Pressure relief. (a) Where necessary... suitable means for relieving excessive pressure accumulating within the compartment when the carbon...

  5. 46 CFR 76.15-40 - Pressure relief.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Carbon Dioxide Extinguishing Systems, Details § 76.15-40 Pressure relief. (a) Where necessary, relatively... means for relieving excessive pressure accumulating within the compartment when the carbon dioxide...

  6. 46 CFR 76.15-40 - Pressure relief.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Carbon Dioxide Extinguishing Systems, Details § 76.15-40 Pressure relief. (a) Where necessary, relatively... means for relieving excessive pressure accumulating within the compartment when the carbon dioxide...

  7. 46 CFR 95.15-40 - Pressure relief.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 95.15-40 Pressure relief. (a) Where necessary... suitable means for relieving excessive pressure accumulating within the compartment when the carbon...

  8. 46 CFR 95.15-40 - Pressure relief.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... EQUIPMENT Carbon Dioxide Extinguishing Systems, Details § 95.15-40 Pressure relief. (a) Where necessary... suitable means for relieving excessive pressure accumulating within the compartment when the carbon...

  9. 46 CFR 76.15-40 - Pressure relief.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Carbon Dioxide Extinguishing Systems, Details § 76.15-40 Pressure relief. (a) Where necessary, relatively... means for relieving excessive pressure accumulating within the compartment when the carbon dioxide...

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

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... relief valves for service other than steam and air need not be provided with a lifting device although a lifting device is desirable if the vapors are such that their release will not create a hazard. (e) If the... service shall be provided with a substantial lifting device so that the disk can be lifted from its...

  11. 46 CFR 153.371 - Minimum relief valve setting for refrigerated 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 refrigerated cargo tanks. 153.371 Section 153.371 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Venting Systems...

  12. 46 CFR 153.371 - Minimum relief valve setting for refrigerated 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 refrigerated cargo tanks. 153.371 Section 153.371 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo Venting Systems...

  13. 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 cargo tanks. 153.370 Section 153.370 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo...

  14. 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 cargo tanks. 153.370 Section 153.370 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Cargo...

  15. 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...

  16. 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...

  17. 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...

  18. 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...

  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. Vent and relief valve maintains low leakage rate over broad temperature range

    NASA Technical Reports Server (NTRS)

    Weitenbeck, R. G.

    1968-01-01

    Low leakage rate, large diameter vent and relief valve operates satisfactorily over a large temperature range by a design that accommodates waviness and distortions due to thermal gradients. It is based on a fixed sealing member having an inclined lapped surface to which a flexible flow gate conforms.

  1. 46 CFR 154.1838 - Discharge by gas pressurization.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) The pressurizing line has: (1) A pressure reducing valve that has a setting that is 90 percent or less of the tank's relief valve setting; and (2) A manual control valve between the pressure reducing valve and the tank....

  2. 49 CFR 192.197 - Control of the pressure of gas delivered from high-pressure distribution systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    .... This device may be either a relief valve or an automatic shutoff that shuts, if the pressure on the... relief valve vented to the outside atmosphere, with the relief valve set to open so that the pressure of gas going to the customer does not exceed a maximum safe value. The relief valve may either be...

  3. New program sizes pressure-relief drums

    SciTech Connect

    Durand, A.A.; Osorio, R.A.; Suarez, R.H.

    1996-05-06

    In accordance with API Recommended Practice 521, a new procedure has been developed for the design of relief drums. The calculation method determines by convergence the most economical length-to-diameter ratio for gas-liquid separation vessels. Drum sizing is based on the separation of a two-phase stream, taking into account the special condition of intermittent flow. Design parameters such as settling velocity and residence time also must be calculated to determine an optimum design. A new program based on a programmable algorithm can be converted from basic language to any other computer language to facilitate vessel-design computations. The program quickly and efficiently computes design values for relief systems used in refineries and petrochemical plants.

  4. Valve assemblies. [for oxygen systems

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Seals and sealing, especially relative to valve designs for O2 systems are investigated. Also considered are high pressure requirements, pressure and flow regulators, and check and relief valves. Valve failure as induced by overstress or abrasion, galling, and ignition of valve parts was detailed.

  5. 49 CFR 179.15 - Pressure relief devices.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Pressure relief devices. 179.15 Section 179.15 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR TANK CARS General Design Requirements § 179.15 Pressure...

  6. 49 CFR 179.103-4 - Safety relief devices and pressure regulators.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Safety relief devices and pressure regulators. 179...) § 179.103-4 Safety relief devices and pressure regulators. (a) Safety relief devices and pressure... design must be provided to protect safety relief devices and pressure regulators from damage....

  7. Combination pressure regulator and safety valve: A Concept

    NASA Technical Reports Server (NTRS)

    Acres, R. L.

    1972-01-01

    Device for regulating high pressure liquefied gas to high pressure vapor generator using liquid oxygen is described. System includes pressure regulation and safety valve features. Construction of the equipment and method of operation are presented.

  8. Study of pressing machine pressure relief characteristics based on AMESim

    NASA Astrophysics Data System (ADS)

    Wang, Chuanli; Zhang, Hui; Yu, Caofeng; Wu, Xiaolei

    2016-01-01

    When a working cylinder of the pressing machine working cylinder was stuck and underwent retracted conversion, pressure shock was high in working cylinder cavity and flow pulsation was distinct in the pipeline due to the high working pressure and frequent retracted transformation of the working cylinder, which not only shortened the service life of the pressing machine, but also exerted serious impacts on the machining precision and quality, especially after the pressing machine applied loads and high-pressure oil in work rod end cavity of working cylinder needed to be relieved in a short time. In order to research and analyze the better pressure relief characteristics of the two types of pressure relief circuits of the pressing machine, the paper established models, carried out simulation and analysis and then made contrastive analysis of the working cylinder rod velocity, rod acceleration and port pressure pulsation according to the simulation results.

  9. 46 CFR 64.71 - Marking of pressure relief devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Marking of pressure relief devices. 64.71 Section 64.71 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING MARINE PORTABLE TANKS... identifying number; and (d) Pipe size of inlet....

  10. 40 CFR 61.242-4 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... each pressure release, the pressure relief device shall be returned to a condition of no detectable.... (2) No later than 5 calendar days after the pressure release, the pressure relief device shall be... release, a new rupture disk shall be installed upstream of the pressure relief device as soon...

  11. Sliding pressure control valve for pneumatic hammer drill

    SciTech Connect

    Polsky, Yarom

    2011-08-30

    A pneumatic device control apparatus and method comprising a ported valve slidably fitted over a feed tube of the pneumatic device, and using a compliant biasing device to constrain motion of the valve to provide asymmetric timing for extended pressurization of a power chamber and reduced pressurization of a return chamber of the pneumatic device. The pneumatic device can be a pneumatic hammer drill.

  12. Device damps fluid pressure oscillations in vent valve

    NASA Technical Reports Server (NTRS)

    Nein, H. J.

    1968-01-01

    Device, containing a tuned series arrangement of two plenum chambers and two orifices, damps high pressure fluid oscillations in a vent valve. Used in conjunction with vent valves, it relieves gas pressure that develops in liquid hydrogen and liquid oxygen tanks used on a space vehicle.

  13. Hydraulic High Pressure Valve Controller Using the In-Situ Pressure Difference

    NASA Technical Reports Server (NTRS)

    Bao, Xiaoqi (Inventor); Sherrit, Stewart (Inventor); Badescu, Mircea (Inventor); Bar-Cohen, Yoseph (Inventor); Hall, Jeffery L. (Inventor)

    2016-01-01

    A hydraulic valve controller that uses an existing pressure differential as some or all of the power source for valve operation. In a high pressure environment, such as downhole in an oil or gas well, the pressure differential between the inside of a pipe and the outside of the pipe may be adequately large to drive a linear slide valve. The valve is operated hydraulically by a piston in a bore. When a higher pressure is applied to one end of the bore and a lower pressure to the other end, the piston moves in response to the pressure differential and drives a valve attached to it. If the pressure differential is too small to drive the piston at a sufficiently high speed, a pump is provided to generate a larger pressure differential to be applied. The apparatus is conveniently constructed using multiport valves, which can be rotary valves.

  14. 40 CFR 265.1054 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...: Pressure relief devices in gas/vapor service. (a) Except during pressure releases, each pressure relief... 40 Protection of Environment 27 2012-07-01 2012-07-01 false Standards: Pressure relief devices in gas/vapor service. 265.1054 Section 265.1054 Protection of Environment ENVIRONMENTAL PROTECTION...

  15. 40 CFR 265.1054 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...: Pressure relief devices in gas/vapor service. (a) Except during pressure releases, each pressure relief... 40 Protection of Environment 26 2011-07-01 2011-07-01 false Standards: Pressure relief devices in gas/vapor service. 265.1054 Section 265.1054 Protection of Environment ENVIRONMENTAL PROTECTION...

  16. 40 CFR 60.482-4 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., 2006 § 60.482-4 Standards: Pressure relief devices in gas/vapor service. (a) Except during pressure releases, each pressure relief device in gas/vapor service shall be operated with no detectable emissions... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standards: Pressure relief devices...

  17. 40 CFR 60.482-4 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., 2006 § 60.482-4 Standards: Pressure relief devices in gas/vapor service. (a) Except during pressure releases, each pressure relief device in gas/vapor service shall be operated with no detectable emissions... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standards: Pressure relief devices...

  18. 40 CFR 60.482-4 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., 2006 § 60.482-4 Standards: Pressure relief devices in gas/vapor service. (a) Except during pressure releases, each pressure relief device in gas/vapor service shall be operated with no detectable emissions... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standards: Pressure relief devices...

  19. 40 CFR 60.482-4 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., 2006 § 60.482-4 Standards: Pressure relief devices in gas/vapor service. (a) Except during pressure releases, each pressure relief device in gas/vapor service shall be operated with no detectable emissions... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards: Pressure relief devices...

  20. 40 CFR 265.1054 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...: Pressure relief devices in gas/vapor service. (a) Except during pressure releases, each pressure relief... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Standards: Pressure relief devices in gas/vapor service. 265.1054 Section 265.1054 Protection of Environment ENVIRONMENTAL PROTECTION...

  1. 49 CFR 192.743 - Pressure limiting and regulating stations: Capacity of relief devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...: Capacity of relief devices. 192.743 Section 192.743 Transportation Other Regulations Relating to... STANDARDS Maintenance § 192.743 Pressure limiting and regulating stations: Capacity of relief devices. (a) Pressure relief devices at pressure limiting stations and pressure regulating stations must have...

  2. Effects of a continuous lateral turning device on pressure relief.

    PubMed

    Do, Nam Ho; Kim, Deog Young; Kim, Jung-Hoon; Choi, Jong Hyun; Joo, So Young; Kang, Na Kyung; Baek, Yoon Su

    2016-01-01

    [Purpose] The purpose of this study was to examine the pressure-relieving effects of a continuous lateral turning device on common pressure ulcer sites. [Subjects] Twenty-four healthy adults participated. [Methods] The design of our continuous lateral turning device was motivated by the need for an adequate pressure-relieving device for immobile and/or elderly people. The procedure of manual repositioning is embodied in our continuous lateral turning device. The interface pressure and time were measured, and comfort grade was evaluated during sessions of continuous lateral turning at 0°, 15°, 30°, and 45°. We quantified the pressure-relieving effect using peak pressure, mean pressure, and pressure time integration. [Results] Participants demonstrated pressure time integration values below the pressure-time threshold at 15°, 30°, and 45° at all the common pressure ulcer sites. Moreover, the most effective angles for pressure relief at the common pressure ulcer sites were 30° at the occiput, 15° at the left scapula, 45° at the right scapula, 45° at the sacrum, 15° at the right heel, and 30° at the left heel. However, angles greater than 30° induced discomfort. [Conclusion] Continuous lateral turning with our specially designed device effectively relieved the pressure of targeted sites. Moreover, the suggested angles of continuous lateral turning can be used to relieve pressure at targeted sites. PMID:27065531

  3. Effects of a continuous lateral turning device on pressure relief

    PubMed Central

    Do, Nam Ho; Kim, Deog Young; Kim, Jung-Hoon; Choi, Jong Hyun; Joo, So Young; Kang, Na Kyung; Baek, Yoon Su

    2016-01-01

    [Purpose] The purpose of this study was to examine the pressure-relieving effects of a continuous lateral turning device on common pressure ulcer sites. [Subjects] Twenty-four healthy adults participated. [Methods] The design of our continuous lateral turning device was motivated by the need for an adequate pressure-relieving device for immobile and/or elderly people. The procedure of manual repositioning is embodied in our continuous lateral turning device. The interface pressure and time were measured, and comfort grade was evaluated during sessions of continuous lateral turning at 0°, 15°, 30°, and 45°. We quantified the pressure-relieving effect using peak pressure, mean pressure, and pressure time integration. [Results] Participants demonstrated pressure time integration values below the pressure-time threshold at 15°, 30°, and 45° at all the common pressure ulcer sites. Moreover, the most effective angles for pressure relief at the common pressure ulcer sites were 30° at the occiput, 15° at the left scapula, 45° at the right scapula, 45° at the sacrum, 15° at the right heel, and 30° at the left heel. However, angles greater than 30° induced discomfort. [Conclusion] Continuous lateral turning with our specially designed device effectively relieved the pressure of targeted sites. Moreover, the suggested angles of continuous lateral turning can be used to relieve pressure at targeted sites. PMID:27065531

  4. 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)

  5. 40 CFR 264.1054 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... relief devices in gas/vapor service. (a) Except during pressure releases, each pressure relief device in... 40 Protection of Environment 27 2012-07-01 2012-07-01 false Standards: Pressure relief devices in gas/vapor service. 264.1054 Section 264.1054 Protection of Environment ENVIRONMENTAL PROTECTION...

  6. 40 CFR 264.1054 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... relief devices in gas/vapor service. (a) Except during pressure releases, each pressure relief device in... 40 Protection of Environment 26 2011-07-01 2011-07-01 false Standards: Pressure relief devices in gas/vapor service. 264.1054 Section 264.1054 Protection of Environment ENVIRONMENTAL PROTECTION...

  7. 40 CFR 63.1030 - Pressure relief devices in gas and vapor service standards.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... § 63.1030 Pressure relief devices in gas and vapor service standards. (a) Compliance schedule. The... section, each pressure relief device in gas and vapor service shall be operated with an instrument reading... 40 Protection of Environment 11 2013-07-01 2013-07-01 false Pressure relief devices in gas...

  8. 40 CFR 63.1030 - Pressure relief devices in gas and vapor service standards.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... § 63.1030 Pressure relief devices in gas and vapor service standards. (a) Compliance schedule. The... section, each pressure relief device in gas and vapor service shall be operated with an instrument reading... 40 Protection of Environment 11 2012-07-01 2012-07-01 false Pressure relief devices in gas...

  9. 40 CFR 63.1011 - Pressure relief devices in gas and vapor service standards.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Pressure relief devices in gas and vapor service standards. (a) Compliance schedule. The owner or operator... section, each pressure relief device in gas or vapor service shall be operated with an instrument reading... 40 Protection of Environment 11 2013-07-01 2013-07-01 false Pressure relief devices in gas...

  10. 40 CFR 63.1011 - Pressure relief devices in gas and vapor service standards.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Pressure relief devices in gas and vapor service standards. (a) Compliance schedule. The owner or operator... section, each pressure relief device in gas or vapor service shall be operated with an instrument reading... 40 Protection of Environment 11 2014-07-01 2014-07-01 false Pressure relief devices in gas...

  11. 40 CFR 264.1054 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... relief devices in gas/vapor service. (a) Except during pressure releases, each pressure relief device in... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Standards: Pressure relief devices in gas/vapor service. 264.1054 Section 264.1054 Protection of Environment ENVIRONMENTAL PROTECTION...

  12. 40 CFR 63.1030 - Pressure relief devices in gas and vapor service standards.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... § 63.1030 Pressure relief devices in gas and vapor service standards. (a) Compliance schedule. The... section, each pressure relief device in gas and vapor service shall be operated with an instrument reading... 40 Protection of Environment 11 2014-07-01 2014-07-01 false Pressure relief devices in gas...

  13. 40 CFR 63.1011 - Pressure relief devices in gas and vapor service standards.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Pressure relief devices in gas and vapor service standards. (a) Compliance schedule. The owner or operator... section, each pressure relief device in gas or vapor service shall be operated with an instrument reading... 40 Protection of Environment 11 2012-07-01 2012-07-01 false Pressure relief devices in gas...

  14. 40 CFR 63.1030 - Pressure relief devices in gas and vapor service standards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... § 63.1030 Pressure relief devices in gas and vapor service standards. (a) Compliance schedule. The... section, each pressure relief device in gas and vapor service shall be operated with an instrument reading... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Pressure relief devices in gas...

  15. 40 CFR 63.1011 - Pressure relief devices in gas and vapor service standards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Pressure relief devices in gas and vapor service standards. (a) Compliance schedule. The owner or operator... section, each pressure relief device in gas or vapor service shall be operated with an instrument reading... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Pressure relief devices in gas...

  16. 30 CFR 18.28 - Devices for pressure relief, ventilation, or drainage.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Devices for pressure relief, ventilation, or... Construction and Design Requirements § 18.28 Devices for pressure relief, ventilation, or drainage. (a) Devices... metal will prevent discharge of flame in explosion tests. (b) Devices for pressure relief,...

  17. 40 CFR 63.165 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... pressure release and being returned to organic HAP service, the pressure relief device shall be monitored... release, a rupture disk shall be installed upstream of the pressure relief device as soon as practicable... relief device in gas/vapor service shall be operated with an instrument reading of less than 500...

  18. 40 CFR 61.242-8 - Standards: Pressure relief services in liquid service and connectors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...: Pressure relief services in liquid service and connectors. (a) If evidence of a potential leak is found by visual, audible, olfactory, or any other detection method at pressure relief devices in liquid service... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Standards: Pressure relief services...

  19. Enhancement of pressurizer safety valve operability by seating design improvement

    SciTech Connect

    Moisidis, N.T.; Ratiu, M.D.

    1995-08-01

    Operating conditions specific to pressurizer safety valves (PSVs) have led to numerous problems and have caused industry and NRC concerns regarding the adequacy of spring-loaded self-actuated safety valves for reactor coolant system (RCS) overpressure protection. Specific concerns are: setpoint drift, spurious actuations, and pressure protection. Specific concerns are: setpoint drift, spurious actuations, and leakage. Based on testing and valve construction analysis of a Crosby model 6M6 PSV (Moisidis and Ratiu, 1992), it was established that the primary contributor to the valve problems is a susceptibility to weak seating. To eliminate spring instability, a new spring washer was designed, which guides the spring and precludes its rotation from the reference installed position. Results of tests performed on a prototype PSV equipped with the modified upper spring washer has shown significant improvements in valve operability and a consistent setpoint reproducibility to less than {+-}1% of the PSV setpoint (testing of baseline, unmodified valve, resulted in a setpoint drift of {+-} 2%). Enhanced valve operability will result in a significant decrease in operating and maintenance costs associated with valve maintenance and testing. In addition, the enhanced setpoint reproducibility will allow the development of a nitrogen to steam correlation for future in-house PSV testing which will result in further reductions in costs associated with valve testing.

  20. Design criteria monograph for pressure regulators, relief valves, check valves, burst disks, and explosive valves

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Monograph reviews and assesses current design practices, and from them establishes firm guidance for achieving greater consistency in design, increased reliability in end product, and greater efficiency in design effort. Five devices are treated separately. Guides to aid in configuration selection are outlined.

  1. 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

  2. Detail view of valve mechanisms and goverenor on high pressure ...

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

    Detail view of valve mechanisms and goverenor on high pressure stage engine of unit 43. - Burnsville Natural Gas Pumping Station, Saratoga Avenue between Little Kanawha River & C&O Railroad line, Burnsville, Braxton County, WV

  3. Inservice leak testing of primary pressure isolation valves

    SciTech Connect

    Livingston, R.A.

    1983-02-01

    This report discusses the inservice leak testing of primary pressure isolation valves in commercial power reactors which was investigated to identify problems with current test procedures and requirements. Nine utilities were surveyed to gather information which is presented in this report. An analysis of the survey information was performed, resulting in recommended changes to improve valve leak testing requirements currently invoked by Section XI of the ASME Boiler and Pressure Vessel Code, Plant Technical Specifications, and Regulatory Guides addressing this subject.

  4. Effects of pressure and temperature on gate valve unwedging

    SciTech Connect

    Damerell, P.S.; Harrison, D.H.; Hayes, P.W.; Simons, J.W.; Walker, T.A.

    1996-12-01

    The stem thrust required to unwedge a gate valve is influenced by the pressure and temperature when the valve is closed and by the changes in these conditions between closure and opening. {open_quotes}Pressure locking{close_quotes} and {open_quotes}thermal binding{close_quotes} refer to situations where pressure and temperature effects cause the unwedging load to be much higher than normal. A model of these phenomena has been developed. Wedging (closure) is modeled as developing an {open_quotes}interference{close_quotes} between the disk and its seat rings in the valve. The effects of pressure and temperature are analyzed to determine the change in this disk-to-seat {open_quotes}interference{close_quotes}. Flexibilities, of the disk, body, stem and yoke strongly influence the unwedging thrust. Calculations and limited comparisons to data have been performed for a range of valve designs and scenarios. Pressure changes can increase the unwedging load when there is either a uniform pressure decrease, or a situation where the bonnet pressure exceeds the pressures in the adjacent piping. Temperature changes can increase the unwedging load when: (1) valve closure at elevated system temperature produces a delayed stem expansion, (2) a temperature increase after closure produces a bonnet pressure increase, or (3) a temperature change after closure produces an increase in the disk-to-seat {open_quotes}interference{close_quotes} or disk-to-seat friction.

  5. Pressure locking and thermal binding of gate valves

    SciTech Connect

    Kelly, E.M.

    1996-12-01

    Pressure locking and thermal binding represent potential common mode failure mechanisms that can cause safety-related power-operated gate valves to fail in the closed position, thus rendering redundant safety-related systems incapable of performing their safety functions. Supplement 6 to Generic Letter 89-10, {open_quotes}Safety-Related Motor-Operated Gate Valve Testing and Surveillance,{close_quotes} provided an acceptable approach to addressing pressure locking and thermal binding of gate valves. More recently, the NRC has issued Generic Letter 95-07, {open_quotes}Pressure Locking and Thermal Binding of Safety-Related Power-Operated Gate Valves,{close_quotes} to request that licensees take certain actions to ensure that safety-related power-operated gate valves that are susceptible to pressure locking or thermal binding are capable of performing their safety functions within the current licensing bases. Over the past two years, several plants in Region I determined that valves in certain systems were potentially susceptible to pressure locking and thermal binding, and have taken various corrective actions. The NRC Region I Systems Engineering Branch has been actively involved in the inspection of licensee actions in response to the pressure locking and thermal binding issue. Region I continues to maintain an active involvement in this area, including participation with the Office of Nuclear Reactor Regulation in reviewing licensee responses to Generic Letter 95-07.

  6. Enhancement of pressurizer safety valve operability by seating design improvement

    SciTech Connect

    Moisidis, N.T.; Ratiu, M.D.

    1994-12-31

    Operating conditions specific to Pressurizer Safety Valves (PSVs) have led to numerous problems and have caused industry and NRC concerns regarding the adequacy of spring loaded self-actuated safety valves for Reactor Coolant System (RCS) overpressure protection. Specific concerns are: setpoint drift, spurious actuations and leakage. Based on testing and valve construction analysis of a Crosby model 6M6 PSV, it was established that the primary contributor to the valve problems is a susceptibility to weak seating. To eliminate spring instability, a new spring washer was designed, which guides the spring and precludes its rotation from the reference installed position. Results of tests performed on a prototype PSV equipped with the modified upper spring washer has shown significant improvements in valve operability and a consistent setpoint reproducibility to less than {+-}1% of the PSV setpoint (testing of baseline, unmodified valve, resulted in a setpoint drift of {+-}2%). Enhanced valve operability will result in a significant decrease in operating and maintenance costs associated with valve maintenance and testing. In addition, the enhanced setpoint reproducibility will allow the development of a nitrogen to steam correlation for future in-house PSV testing which will result in further reductions in costs associated with valve testing.

  7. 46 CFR 64.69 - Location of the pressure relief device.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Location of the pressure relief device. 64.69 Section 64.69 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 §...

  8. 46 CFR 64.69 - Location of the pressure relief device.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Location of the pressure relief device. 64.69 Section 64.69 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 §...

  9. 46 CFR 64.69 - Location of the pressure relief device.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Location of the pressure relief device. 64.69 Section 64.69 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 §...

  10. 46 CFR 64.69 - Location of the pressure relief device.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Location of the pressure relief device. 64.69 Section 64.69 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 §...

  11. 46 CFR 64.69 - Location of the pressure relief device.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Location of the pressure relief device. 64.69 Section 64.69 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 §...

  12. 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

    ... reference; see 46 CFR 52.01-1) except as noted otherwise in this section. (2) A safety valve must: (i) Be... safety valve is the nominal diameter (as defined in 56.07-5(b)) of the inlet opening. (8) Lever or... necessary, lever or weighted safety valves shall not be used. All such replacements shall conform to...

  13. Valve selection handbook. Third edition

    SciTech Connect

    Zappe, R.W. )

    1991-01-01

    This book covers the fundamentals of value construction and application, and analyzes the different hazards and requirements of all types of industrial fluid flow situations. This book expands the coverage of pressure relief valves and rupture discs. It includes a new section on damping valve chatter, which is a serious problem in installations such as atomic power plants where valve chatter could have catastrophic consequences to the safety of the plant. There is also new information on performance of spring-loaded pressure relief valves and a closer examination of valve selection with respect to rupture discs and explosion venting.

  14. Measuring Tissue Perfusion During Pressure Relief Maneuvers: Insights Into Preventing Pressure Ulcers

    PubMed Central

    Makhsous, Mohsen; Priebe, Michael; Bankard, James; Rowles, Diana; Zeigler, Mary; Chen, David; Lin, Fang

    2007-01-01

    Background/Objective: To study the effect on tissue perfusion of relieving interface pressure using standard wheelchair pushups compared with a mechanical automated dynamic pressure relief system. Design: Repeated measures in 2 protocols on 3 groups of subjects. Participants: Twenty individuals with motor-complete paraplegia below T4, 20 with motor-complete tetraplegia, and 20 able-bodied subjects. Methods: Two 1-hour sitting protocols: dynamic protocol, sitting configuration alternated every 10 minutes between a normal sitting configuration and an off-loading configuration; wheelchair pushup protocol, normal sitting configuration with standard wheelchair pushup once every 20 minutes. Main Outcome Measures: Transcutaneous partial pressures of oxygen and carbon dioxide measured from buttock overlying the ischial tuberosity and interface pressure measured at the seat back and buttocks. Perfusion deterioration and recovery times were calculated during changes in interface pressures. Results: In the off-loading configuration, concentrated interface pressure during the normal sitting configuration was significantly diminished, and tissue perfusion was significantly improved. Wheelchair pushups showed complete relief of interface pressure but incomplete recovery of tissue perfusion. Conclusions: Interface pressure analysis does not provide complete information about the effectiveness of pressure relief maneuvers. Measures of tissue perfusion may help establish more effective strategies. Relief achieved by standard wheelchair pushups may not be sufficient to recover tissue perfusion compromised during sitting; alternate maneuvers may be necessary. The dynamic seating system provided effective pressure relief with sustained reduction in interface pressure adequate for complete recovery of tissue perfusion. Differences in perfusion recovery times between subjects with spinal cord injury (SCI) and controls raise questions about the importance of changes in vascular responses

  15. 40 CFR 63.165 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Standards: Pressure relief devices in gas/vapor service. (a) Except during pressure releases, each pressure... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Standards: Pressure relief devices in gas/vapor service. 63.165 Section 63.165 Protection of Environment ENVIRONMENTAL PROTECTION...

  16. 40 CFR 63.165 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Standards: Pressure relief devices in gas/vapor service. (a) Except during pressure releases, each pressure... 40 Protection of Environment 10 2012-07-01 2012-07-01 false Standards: Pressure relief devices in gas/vapor service. 63.165 Section 63.165 Protection of Environment ENVIRONMENTAL PROTECTION...

  17. 40 CFR 60.482-4a - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Standards: Pressure relief devices in gas/vapor service. (a) Except during pressure releases, each pressure... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Standards: Pressure relief devices in gas/vapor service. 60.482-4a Section 60.482-4a Protection of Environment ENVIRONMENTAL...

  18. 40 CFR 60.482-4a - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Standards: Pressure relief devices in gas/vapor service. (a) Except during pressure releases, each pressure... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Standards: Pressure relief devices in gas/vapor service. 60.482-4a Section 60.482-4a Protection of Environment ENVIRONMENTAL...

  19. 40 CFR 60.482-4a - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Standards: Pressure relief devices in gas/vapor service. (a) Except during pressure releases, each pressure... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Standards: Pressure relief devices in gas/vapor service. 60.482-4a Section 60.482-4a Protection of Environment ENVIRONMENTAL...

  20. 40 CFR 60.482-4a - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Standards: Pressure relief devices in gas/vapor service. (a) Except during pressure releases, each pressure... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards: Pressure relief devices in gas/vapor service. 60.482-4a Section 60.482-4a Protection of Environment ENVIRONMENTAL...

  1. High-Pressure Valve With Controlled Seating Force

    NASA Technical Reports Server (NTRS)

    Bradley, R. H.

    1987-01-01

    Poppet and seat less likely to be damaged by faulty operation. Improvements in widely-used high-pressure valve increase accuracy of preloading of poppet. Redesigned valve prevents metal shavings and other debris from developing during operation, installation, or removal. New features include secondary seal in cap. Belleville washers create precise value of seating force. If installer attempts to exceed force, torque limiter gives tactile and aural warning and makes further force increases difficult.

  2. Airblast fuel injection with adjustable valve cracking pressure

    SciTech Connect

    Halvorsen, R.M.

    1990-10-16

    This patent describes an airblast fuel injector having injector body means for forming an inner air chamber with a downstream air discharge orifice, an outer air chamber with a downstream air discharge orifice and an annular fuel chamber between the inner and outer air chambers with a downstream fuel discharge orifice. The injector body means forming a passage between the annular fuel chamber and an upstream fuel inlet chamber, a valve seat member adjustably received in the passage and having a fuel bore for receiving fuel from the fuel inlet chamber and terminating in a fuel discharge port, and an arcuate spring valve disposed on the injector body means and including a cantilever end portion overlying the fuel discharge port and biased against the valve seat member over the fuel discharge port when fuel pressure is below a minimum value and operable when fuel pressure exceeds a selected value to allow fuel flow discharge from the fuel discharge port to the annular fuel chamber. The valve seat member being adjustable in position in the passage relative to the cantilever end portion of the valve from the exterior of the injector body means to adjust the valve opening pressure.

  3. 14 CFR 23.365 - Pressurized cabin loads.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... zero up to the maximum relief valve setting. (b) The external pressure distribution in flight, and any... corresponding to the maximum relief valve setting multiplied by a factor of 1.33, omitting other loads. (e) If...

  4. 14 CFR 23.365 - Pressurized cabin loads.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... zero up to the maximum relief valve setting. (b) The external pressure distribution in flight, and any... corresponding to the maximum relief valve setting multiplied by a factor of 1.33, omitting other loads. (e) If...

  5. 49 CFR 192.199 - Requirements for design of pressure relief and limiting devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    .... Except for rupture discs, each pressure relief or pressure limiting device must: (a) Be constructed of..., pipe, and fittings located between the system to be protected and the pressure relieving device,...

  6. Application of RELAP5/MOD1 for calculation of safety and relief valve discharge piping hydrodynamic loads. Final report. [PWR

    SciTech Connect

    Not Available

    1982-12-01

    A series of operability tests of spring-loaded safety valves was performed at Combustion Engineering in Windsor, CT as part of the PWR Safety and Relief Valve Test Program conducted by EPRI on behalf of PWR Utilities in response to the recommendations of NUREG-0578 and the requirements of the NRC. Experimental data from five of the safety valve tests are compared with RELAP5/MOD1 calculations to evaluate the capability of the code to determine the fluid-induced transient loads on downstream piping. Comparisons between data and calculations are given for transients with discharge of steam, water, and water loop seal followed by steam. RELAP5/MOD1 provides useful engineering estimates of the fluid-induced piping loads for all cases.

  7. 40 CFR 61.242-4 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... devices in gas/vapor service. (a) Except during pressure releases, each pressure relief device in gas... 40 Protection of Environment 8 2011-07-01 2011-07-01 false Standards: Pressure relief devices in gas/vapor service. 61.242-4 Section 61.242-4 Protection of Environment ENVIRONMENTAL PROTECTION...

  8. 40 CFR 61.242-4 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... devices in gas/vapor service. (a) Except during pressure releases, each pressure relief device in gas... 40 Protection of Environment 9 2012-07-01 2012-07-01 false Standards: Pressure relief devices in gas/vapor service. 61.242-4 Section 61.242-4 Protection of Environment ENVIRONMENTAL PROTECTION...

  9. High-pressure cryogenic valves for the Vulcain rocket motor

    NASA Astrophysics Data System (ADS)

    Garceau, P.; Meyer, F.

    The high-pressure valve developed to control the flow of liquid oxygen or hydrogen into the gas generator of the ESA Vulcain rocket motor is described. The spherical ball-seal design employed provides high reliability over a service lifetime of 5000 on-off actuations at temperatures 20-350 K and pressures up to 200 bar. Leakage is limited to a few cu cm/sec of hydrogen at 20 K. The steps in the development process, from the definition of the valve specifications to the fabrication and testing phase are reviewed, and the final design is shown in drawings, diagrams, and photographs.

  10. Workshop on gate valve pressure locking and thermal binding

    SciTech Connect

    Brown, E.J.

    1995-07-01

    The purpose of the Workshop on Gate Valve Pressure Locking and Thermal Binding was to discuss pressure locking and thermal binding issues that could lead to inoperable gate valves in both boiling water and pressurized water reactors. The goal was to foster exchange of information to develop the technical bases to understand the phenomena, identify the components that are susceptible, discuss actual events, discuss the safety significance, and illustrate known corrective actions that can prevent or limit the occurrence of pressure locking or thermal binding. The presentations were structured to cover U.S. Nuclear Regulatory Commission staff evaluation of operating experience and planned regulatory activity; industry discussions of specific events, including foreign experience, and efforts to determine causes and alleviate the affects; and valve vendor experience and recommended corrective action. The discussions indicated that identifying valves susceptible to pressure locking and thermal binding was a complex process involving knowledge of components, systems, and plant operations. The corrective action options are varied and straightforward.

  11. Pressure tracking control of vehicle ABS using piezo valve modulator

    NASA Astrophysics Data System (ADS)

    Jeon, Juncheol; Choi, Seung-Bok

    2011-03-01

    This paper presents a wheel slip control for the ABS(anti-lock brake system) of a passenger vehicle using a controllable piezo valve modulator. The ABS is designed to optimize for braking effectiveness and good steerability. As a first step, the principal design parameters of the piezo valve and pressure modulator are appropriately determined by considering the braking pressure variation during the ABS operation. The proposed piezo valve consists of a flapper, pneumatic circuit and a piezostack actuator. In order to get wide control range of the pressure, the pressure modulator is desired. The modulator consists of a dual-type cylinder filled with different substances (fluid and gas) and a piston rod moving vertical axis to transmit the force. Subsequently, a quarter car wheel slip model is formulated and integrated with the governing equation of the piezo valve modulator. A sliding mode controller to achieve the desired slip rate is then designed and implemented. Braking control performances such as brake pressure and slip rate are evaluated via computer simulations.

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. 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...

  17. Reed Valve Regulates Welding Back-Purge Pressure

    NASA Technical Reports Server (NTRS)

    Coby, J. Ben, Jr.; Weeks, Jack L.

    1991-01-01

    Simple modification yields welds of better quality. Reed valve halves fluctuations in pressure in back-purge chamber attached to workpiece undergoing keyhole plasma arc welding. Identical to one used in fuel system of two-cycle gasoline engine. Backbead smoother, and weld penetrates more uniformly.

  18. 31. DETAIL OF PRESSURE GAUGE AND ASSOCIATED VALVES AND TUBING ...

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

    31. DETAIL OF PRESSURE GAUGE AND ASSOCIATED VALVES AND TUBING FOR STRETCH SLING CYLINDER. GAUGE LOCATED IN SOUTHWEST CORNER OF SLC-3W MST STATION 78. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  19. 46 CFR 54.15-15 - Relief devices for unfired steam boilers, evaporators, and heat exchangers (modifies UG-126).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... between atmospheric pressure and 15 p.s.i.g., may use a rupture disc as an alternative to the safety valve... HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PRESSURE VESSELS Pressure-Relief Devices § 54.15-15 Relief... safety valve set to relieve at a pressure not exceeding the “maximum allowable working pressure” of...

  20. 46 CFR 54.15-15 - Relief devices for unfired steam boilers, evaporators, and heat exchangers (modifies UG-126).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... between atmospheric pressure and 15 p.s.i.g., may use a rupture disc as an alternative to the safety valve... HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PRESSURE VESSELS Pressure-Relief Devices § 54.15-15 Relief... safety valve set to relieve at a pressure not exceeding the “maximum allowable working pressure” of...

  1. 46 CFR 54.15-15 - Relief devices for unfired steam boilers, evaporators, and heat exchangers (modifies UG-126).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... between atmospheric pressure and 15 p.s.i.g., may use a rupture disc as an alternative to the safety valve... HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PRESSURE VESSELS Pressure-Relief Devices § 54.15-15 Relief... safety valve set to relieve at a pressure not exceeding the “maximum allowable working pressure” of...

  2. 46 CFR 54.15-15 - Relief devices for unfired steam boilers, evaporators, and heat exchangers (modifies UG-126).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... between atmospheric pressure and 15 p.s.i.g., may use a rupture disc as an alternative to the safety valve... HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PRESSURE VESSELS Pressure-Relief Devices § 54.15-15 Relief... safety valve set to relieve at a pressure not exceeding the “maximum allowable working pressure” of...

  3. 46 CFR 54.15-15 - Relief devices for unfired steam boilers, evaporators, and heat exchangers (modifies UG-126).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... between atmospheric pressure and 15 p.s.i.g., may use a rupture disc as an alternative to the safety valve... HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PRESSURE VESSELS Pressure-Relief Devices § 54.15-15 Relief... safety valve set to relieve at a pressure not exceeding the “maximum allowable working pressure” of...

  4. 40 CFR 65.111 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...: Pressure relief devices in gas/vapor service. (a) Compliance schedule. The owner or operator shall comply... 40 Protection of Environment 16 2014-07-01 2014-07-01 false Standards: Pressure relief devices in gas/vapor service. 65.111 Section 65.111 Protection of Environment ENVIRONMENTAL PROTECTION...

  5. 40 CFR 65.111 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 15 2011-07-01 2011-07-01 false Standards: Pressure relief devices in gas/vapor service. 65.111 Section 65.111 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONSOLIDATED FEDERAL AIR RULE Equipment Leaks § 65.111 Standards: Pressure relief devices in gas/vapor service....

  6. 40 CFR 65.111 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...: Pressure relief devices in gas/vapor service. (a) Compliance schedule. The owner or operator shall comply... 40 Protection of Environment 16 2012-07-01 2012-07-01 false Standards: Pressure relief devices in gas/vapor service. 65.111 Section 65.111 Protection of Environment ENVIRONMENTAL PROTECTION...

  7. 40 CFR 65.111 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...: Pressure relief devices in gas/vapor service. (a) Compliance schedule. The owner or operator shall comply... 40 Protection of Environment 16 2013-07-01 2013-07-01 false Standards: Pressure relief devices in gas/vapor service. 65.111 Section 65.111 Protection of Environment ENVIRONMENTAL PROTECTION...

  8. 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.

  9. 49 CFR 195.264 - Impoundment, protection against entry, normal/emergency venting or pressure/vacuum relief for...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... relief venting must be provided for each atmospheric pressure breakout tank. Pressure/vacuum-relieving... specified: (1) Normal/emergency relief venting installed on atmospheric pressure tanks built to API... relief venting installed on atmospheric pressure tanks (such as those built to API Standard 650 or...

  10. 49 CFR 195.264 - Impoundment, protection against entry, normal/emergency venting or pressure/vacuum relief for...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... relief venting must be provided for each atmospheric pressure breakout tank. Pressure/vacuum-relieving... specified: (1) Normal/emergency relief venting installed on atmospheric pressure tanks built to API... relief venting installed on atmospheric pressure tanks (such as those built to API Standard 650 or...

  11. 49 CFR 195.264 - Impoundment, protection against entry, normal/emergency venting or pressure/vacuum relief for...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... relief venting must be provided for each atmospheric pressure breakout tank. Pressure/vacuum-relieving... specified: (1) Normal/emergency relief venting installed on atmospheric pressure tanks built to API... relief venting installed on atmospheric pressure tanks (such as those built to API Standard 650 or...

  12. 49 CFR 195.264 - Impoundment, protection against entry, normal/emergency venting or pressure/vacuum relief for...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... relief venting must be provided for each atmospheric pressure breakout tank. Pressure/vacuum-relieving... specified: (1) Normal/emergency relief venting installed on atmospheric pressure tanks built to API... relief venting installed on atmospheric pressure tanks (such as those built to API Standard 650 or...

  13. 46 CFR 154.452 - External pressure.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false External pressure. 154.452 Section 154.452 Shipping... Independent Tank Type C and Process Pressure Vessels § 154.452 External pressure. The design external pressure...) for tanks without a vacuum relief valve. P2=0, or the pressure relief valve setting for an...

  14. 46 CFR 154.452 - External pressure.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false External pressure. 154.452 Section 154.452 Shipping... Independent Tank Type C and Process Pressure Vessels § 154.452 External pressure. The design external pressure...) for tanks without a vacuum relief valve. P2=0, or the pressure relief valve setting for an...

  15. 46 CFR 154.452 - External pressure.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false External pressure. 154.452 Section 154.452 Shipping... Independent Tank Type C and Process Pressure Vessels § 154.452 External pressure. The design external pressure...) for tanks without a vacuum relief valve. P2=0, or the pressure relief valve setting for an...

  16. 46 CFR 154.452 - External pressure.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false External pressure. 154.452 Section 154.452 Shipping... Independent Tank Type C and Process Pressure Vessels § 154.452 External pressure. The design external pressure...) for tanks without a vacuum relief valve. P2=0, or the pressure relief valve setting for an...

  17. 46 CFR 154.452 - External pressure.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false External pressure. 154.452 Section 154.452 Shipping... Independent Tank Type C and Process Pressure Vessels § 154.452 External pressure. The design external pressure...) for tanks without a vacuum relief valve. P2=0, or the pressure relief valve setting for an...

  18. Pressure Relief Devices for High-Pressure Gaseous Storage Systems: Applicability to Hydrogen Technology

    SciTech Connect

    Kostival, A.; Rivkin, C.; Buttner, W.; Burgess, R.

    2013-11-01

    Pressure relief devices (PRDs) are viewed as essential safety measures for high-pressure gas storage and distribution systems. These devices are used to prevent the over-pressurization of gas storage vessels and distribution equipment, except in the application of certain toxic gases. PRDs play a critical role in the implementation of most high-pressure gas storage systems and anyone working with these devices should understand their function so they can be designed, installed, and maintained properly to prevent any potentially dangerous or fatal incidents. As such, the intention of this report is to introduce the reader to the function of the common types of PRDs currently used in industry. Since high-pressure hydrogen gas storage systems are being developed to support the growing hydrogen energy infrastructure, several recent failure incidents, specifically involving hydrogen, will be examined to demonstrate the results and possible mechanisms of a device failure. The applicable codes and standards, developed to minimize the risk of failure for PRDs, will also be reviewed. Finally, because PRDs are a critical component for the development of a successful hydrogen energy infrastructure, important considerations for pressure relief devices applied in a hydrogen gas environment will be explored.

  19. 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...

  20. System for detecting operating errors in a variable valve timing engine using pressure sensors

    DOEpatents

    Wiles, Matthew A.; Marriot, Craig D

    2013-07-02

    A method and control module includes a pressure sensor data comparison module that compares measured pressure volume signal segments to ideal pressure volume segments. A valve actuation hardware remedy module performs a hardware remedy in response to comparing the measured pressure volume signal segments to the ideal pressure volume segments when a valve actuation hardware failure is detected.

  1. The efficacy of pressure relief maneuvers in spinal cord injury patients, a clinical study

    NASA Astrophysics Data System (ADS)

    Ho, Thuan; Nguyen, Ahn Thu; Lichy, Alison; Groah, Suzanne; Ramella-Roman, Jessica C.

    2014-02-01

    Pressure reliefs are recommended to wheelchair bound individuals to control and minimize skin damage. To this date recommendation on duration and intervals between pressure reliefs is not clear. Recent studies have shown a relationship between reduction in tissue perfusion and oxygenation due to pressure and skin pathophysiologic changes. We have developed a fiber-optics probe that allows measurement of oxygenation in addition to perfusion in real time; this low profile probe can be utilized while sitting and during pressure reliefs. We have conducted a clinical trial at the National Rehabilitation Hospital on individual with spinal cord injury. The overriding goal of this project was to develop the evidence base for clinical recommendations on pressure reliefs. Results of the study will be presented.

  2. 46 CFR 56.50-25 - Safety and relief valve escape piping.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 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...

  3. 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...

  4. 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...

  5. 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...

  6. 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...

  7. Innovative, High-Pressure, Cryogenic Control Valve: Short Face-to-Face, Reduced Cost

    NASA Technical Reports Server (NTRS)

    Wilkes, Karlin; Larsen, Ed; McCourt, Jackson

    2003-01-01

    A control valve that can throttle high-pressure cryogenic fluid embodies several design features that distinguish it over conventional valves designed for similar applications. Field and design engineers worked together to create a valve that would simplify installation, trim changes, and maintenance, thus reducing overall cost. The seals and plug stem packing were designed to perform optimally in cryogenic temperature ranges. Unlike conventional high-pressure cryogenic valves, the trim size can be changed independent of the body.

  8. Longitudinal Impedance Tomography for Blood Pressure Characterization of Valve Deformation

    PubMed Central

    Vahabi, Zahra; Amirfattahi, Rasool

    2015-01-01

    Aorta is formed in a dynamic environment which gives rise to imbalances between many forces that tend to extend the diameter and length. Furthermore, internal forces tend to resist this extension. Impedance tomography can show this imbalance to stimulate the stenosis of aortic valve, growth of the elastic, collagen and to effectively reduce the stresses in the underlying tissue. In blood flow, auscultation noises occurred and in the echocardiography decrease in left ventricular ejection speed can be observed. In this paper, we have modeled an aorta based on anatomical studies to simulate natural, 20% and 30% stenosis as usual heart disease to early diagnosis. Valve deformation causes different impedance tomography in 3D mesh of aorta as blood pressure. Remodeling of aorta and its flow is found when a cylindrical slice of the fully retracted blood aorta is cut longitudinally through the wall. PMID:26120568

  9. Significant issues and changes for ANSI/ASME OM-1 1981, part 1, ASME OMc code-1994, and ASME OM Code-1995, Appendix I, inservice testing of pressure relief devices in light water reactor power plants

    SciTech Connect

    Seniuk, P.J.

    1996-12-01

    This paper identifies significant changes to the ANSI/ASME OM-1 1981, Part 1, and ASME Omc Code-1994 and ASME OM Code-1995, Appendix I, {open_quotes}Inservice Testing of Pressure Relief Devices in Light-Water Reactor Power Plants{close_quotes}. The paper describes changes to different Code editions and presents insights into the direction of the code committee and selected topics to be considered by the ASME O&M Working Group on pressure relief devices. These topics include scope issues, thermal relief valve issues, as-found and as-left set-pressure determinations, exclusions from testing, and cold setpoint bench testing. The purpose of this paper is to describe some significant issues being addressed by the O&M Working Group on Pressure Relief Devices (OM-1). The writer is currently the chair of OM-1 and the statements expressed herein represents his personal opinion.

  10. 49 CFR 179.15 - Pressure relief devices.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... of the static head and gas padding pressure and the lading vapor pressure at the following reference... tank burst pressure but no more than 33 percent of the minimum tank burst pressure. (3) The vapor tight... detection device must be closed during transportation. (3) The vapor tight pressure and the...

  11. 49 CFR 179.15 - Pressure relief devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... of the static head and gas padding pressure and the lading vapor pressure at the following reference... tank burst pressure but no more than 33 percent of the minimum tank burst pressure. (3) The vapor tight... detection device must be closed during transportation. (3) The vapor tight pressure and the...

  12. 49 CFR 179.15 - Pressure relief devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... of the static head and gas padding pressure and the lading vapor pressure at the following reference... tank burst pressure but no more than 33 percent of the minimum tank burst pressure. (3) The vapor tight... detection device must be closed during transportation. (3) The vapor tight pressure and the...

  13. Compression relief engine brake

    SciTech Connect

    Meneely, V.A.

    1987-10-06

    A compression relief brake is described for four cycle internal-combustion engines, comprising: a pressurized oil supply; means for selectively pressurizing a hydraulic circuit with oil from the oil supply; a master piston and cylinder communicating with a slave piston and cylinder via the hydraulic circuit; an engine exhaust valve mechanically coupled to the engine and timed to open during the exhaust cycle of the engine the exhaust valve coupled to the slave piston. The exhaust valve is spring-based in a closed state to contact a valve seat; a sleeve frictionally and slidably disposed within a cavity defined by the slave piston which cavity communicates with the hydraulic circuit. When the hydraulic circuit is selectively pressurized and the engine is operating the sleeve entraps an incompressible volume of oil within the cavity to generate a displacement of the slave piston within the slave cylinder, whereby a first gap is maintained between the exhaust valve and its associated seat; and means for reciprocally activating the master piston for increasing the pressure within the previously pressurized hydraulic circuit during at least a portion of the expansion cycle of the engine whereby a second gap is reciprocally maintained between the exhaust valve and its associated seat.

  14. Design of a cyclic pressure bioreactor for the ex vivo study of aortic heart valves.

    PubMed

    Schipke, Kimberly J; To, S D Filip; Warnock, James N

    2011-01-01

    The aortic valve, located between the left ventricle and the aorta, allows for unidirectional blood flow, preventing backflow into the ventricle. Aortic valve leaflets are composed of interstitial cells suspended within an extracellular matrix (ECM) and are lined with an endothelial cell monolayer. The valve withstands a harsh, dynamic environment and is constantly exposed to shear, flexion, tension, and compression. Research has shown calcific lesions in diseased valves occur in areas of high mechanical stress as a result of endothelial disruption or interstitial matrix damage(1-3). Hence, it is not surprising that epidemiological studies have shown high blood pressure to be a leading risk factor in the onset of aortic valve disease(4). The only treatment option currently available for valve disease is surgical replacement of the diseased valve with a bioprosthetic or mechanical valve(5). Improved understanding of valve biology in response to physical stresses would help elucidate the mechanisms of valve pathogenesis. In turn, this could help in the development of non-invasive therapies such as pharmaceutical intervention or prevention. Several bioreactors have been previously developed to study the mechanobiology of native or engineered heart valves(6-9). Pulsatile bioreactors have also been developed to study a range of tissues including cartilage(10), bone(11) and bladder(12). The aim of this work was to develop a cyclic pressure system that could be used to elucidate the biological response of aortic valve leaflets to increased pressure loads. The system consisted of an acrylic chamber in which to place samples and produce cyclic pressure, viton diaphragm solenoid valves to control the timing of the pressure cycle, and a computer to control electrical devices. The pressure was monitored using a pressure transducer, and the signal was conditioned using a load cell conditioner. A LabVIEW program regulated the pressure using an analog device to pump compressed

  15. Dynamical behaviour of three-way throttle valve with pressure gradient stabilization

    NASA Astrophysics Data System (ADS)

    Vašina, Martin; Hružík, Lumír; Bureček, Adam; Sikora, Roman

    2015-05-01

    Three-way throttle valves with pressure gradient stabilization are used in order to ensure constant flow independently of load changes of hydraulic motors in hydraulic systems. These valves are used to vibration damping in hydraulic systems too. For this reason, it is suitable to install the valves close to hydraulic motors. The valves also have a positive influence on an increasing of system eigenfrequency. The paper deals with investigation of dynamical behaviour and eigenfrequency of a three-way throttle valve with pressure gradient stabilization in consequence of transient changes.

  16. 40 CFR 63.169 - Standards: Pumps, valves, connectors, and agitators in heavy liquid service; instrumentation...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., and agitators in heavy liquid service; instrumentation systems; and pressure relief devices in liquid...: Pumps, valves, connectors, and agitators in heavy liquid service; instrumentation systems; and pressure relief devices in liquid service. (a) Pumps, valves, connectors, and agitators in heavy liquid...

  17. 40 CFR 63.169 - Standards: Pumps, valves, connectors, and agitators in heavy liquid service; instrumentation...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., and agitators in heavy liquid service; instrumentation systems; and pressure relief devices in liquid...: Pumps, valves, connectors, and agitators in heavy liquid service; instrumentation systems; and pressure relief devices in liquid service. (a) Pumps, valves, connectors, and agitators in heavy liquid...

  18. 40 CFR 63.169 - Standards: Pumps, valves, connectors, and agitators in heavy liquid service; instrumentation...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., and agitators in heavy liquid service; instrumentation systems; and pressure relief devices in liquid...: Pumps, valves, connectors, and agitators in heavy liquid service; instrumentation systems; and pressure relief devices in liquid service. (a) Pumps, valves, connectors, and agitators in heavy liquid...

  19. 40 CFR 63.169 - Standards: Pumps, valves, connectors, and agitators in heavy liquid service; instrumentation...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., and agitators in heavy liquid service; instrumentation systems; and pressure relief devices in liquid...: Pumps, valves, connectors, and agitators in heavy liquid service; instrumentation systems; and pressure relief devices in liquid service. (a) Pumps, valves, connectors, and agitators in heavy liquid...

  20. 40 CFR 63.169 - Standards: Pumps, valves, connectors, and agitators in heavy liquid service; instrumentation...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., and agitators in heavy liquid service; instrumentation systems; and pressure relief devices in liquid...: Pumps, valves, connectors, and agitators in heavy liquid service; instrumentation systems; and pressure relief devices in liquid service. (a) Pumps, valves, connectors, and agitators in heavy liquid...

  1. Results of pressure locking and thermal binding tests of gate valves

    SciTech Connect

    DeWall, K.G.; Watkins, J.C.; McKellar, M.G.; Bramwell, D.

    1998-05-01

    The US Nuclear Regulatory Commission (NRC), Office of Nuclear Regulatory Research, is funding the Idaho National Engineering and Environmental Laboratory (INEEL) in performing research investigating the performance of gate valves subjected to pressure locking and thermal binding conditions. Pressure locking and thermal binding are phenomena that make a closed gate valve difficult to open. Pressure locking can occur when operating sequences or temperature changes cause the pressure of the fluid in the bonnet (and, in most gate valves, between the discs) to be higher than the pressure on the upstream and downstream sides of the disc assembly. Thermal binding can occur when thermal expansion/contraction effects cause the disc to be squeezed between the valve body seats. If the loads associated with pressure locking or thermal binding are very high, the actuator might not have the capacity to open the valve. The authors tested a flexible-wedge gate valve and a double-disc gate valve under pressure locking and thermal binding conditions. The results show that these valves are susceptible to pressure locking; however, they are not significantly affected by thermal binding. For the flexible-wedge gate valve, pressure locking loads (in terms of stem thrust) were higher than corresponding hydrostatic opening loads by a factor of 1.1 to 1.5. For the parallel disc gate valve, pressure locking loads were higher by a factor of 2.05 to 2.4. The results also show that seat leakage affects the bonnet pressurization rate when the valve is subjected to thermally induced pressure locking conditions.

  2. Methods for combining a theoretical and an empirical approach in modelling pressure and flow control valves for CAE-programs for fluid power circuits

    NASA Astrophysics Data System (ADS)

    Handroos, Heikki

    An analytical mathematical model for a fluid power valve uses equations based on physical laws. The parameters consist of physical coefficients, dimensions of the internal elements, spring constants, etc. which are not provided by the component manufacturers. The valve has to be dismantled in order to determine their values. The model is only in accordance with a particular type of valve construction and there are a large number of parameters. This is a major common problem in computer aided engineering (CAE) programs for fluid power circuits. Methods for solving this problem by combining a theoretical and an empirical approach are presented. Analytical models for single stage pressure and flow control valves are brought into forms which contain fewer parameters whose values can be determined from measured characteristic curves. The least squares criterion is employed to identify the parameter values describing the steady state of a valve. The steady state characteristic curves that are required data for this identification are quite often provided by the manufacturers. The parameters describing the dynamics of a valve are determined using a simple noncomputational method using dynamic characteristic curves that can be easily measured. The importance of the identification accuracy of the different parameters of the single stage pressure relief valve model is compared using a parameter sensitivity analysis method. A new comparison method called relative mean value criterion is used to compare the influences of variations of the different parameters to a nominal dynamic response.

  3. 46 CFR 34.15-40 - Pressure relief-T/ALL.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false Pressure relief-T/ALL. 34.15-40 Section 34.15-40 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide... relieving excessive pressure accumulating within the compartment when the carbon dioxide is injected....

  4. 46 CFR 34.15-40 - Pressure relief-T/ALL.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Pressure relief-T/ALL. 34.15-40 Section 34.15-40 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide... relieving excessive pressure accumulating within the compartment when the carbon dioxide is injected....

  5. 46 CFR 34.15-40 - Pressure relief-T/ALL.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false Pressure relief-T/ALL. 34.15-40 Section 34.15-40 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide... relieving excessive pressure accumulating within the compartment when the carbon dioxide is injected....

  6. 46 CFR 34.15-40 - Pressure relief-T/ALL.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false Pressure relief-T/ALL. 34.15-40 Section 34.15-40 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide... relieving excessive pressure accumulating within the compartment when the carbon dioxide is injected....

  7. 46 CFR 34.15-40 - Pressure relief-T/ALL.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 1 2012-10-01 2012-10-01 false Pressure relief-T/ALL. 34.15-40 Section 34.15-40 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS FIREFIGHTING EQUIPMENT Carbon Dioxide... relieving excessive pressure accumulating within the compartment when the carbon dioxide is injected....

  8. 49 CFR 179.103-4 - Safety relief devices and pressure regulators.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Safety relief devices and pressure regulators. 179...) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR TANK CARS Specifications for Pressure Tank Car Tanks (Classes DOT-105, 109, 112, 114 and...

  9. Non-reclosing pressure relief device for vacuum systems

    DOEpatents

    Swansiger, William A.

    1994-01-01

    A non-reclosing overpressure protection device such as a rupture disc provides a non-reclosing opening upon forcible contact with a knife blade. A bellows, having an inlet capable of being sealably connected to a source of pressure (the vacuum system) and an outlet containing the rupture disc, transmits the pressure in the system to the disc. The bellows maintains the disc away from the knife when the pressure is below an overpressure amount, and carries the disc to a position when the pressure is above an overpressure amount where the disc is ruptured by the knife.

  10. Non-reclosing pressure relief device for vacuum systems

    DOEpatents

    Swansiger, W.A.

    1994-02-08

    A non-reclosing overpressure protection device such as a rupture disc provides a non-reclosing opening upon forcible contact with a knife blade. A bellows, having an inlet capable of being sealably connected to a source of pressure (the vacuum system) and an outlet containing the rupture disc, transmits the pressure in the system to the disc. The bellows maintains the disc away from the knife when the pressure is below an overpressure amount, and carries the disc to a position when the pressure is above an overpressure amount where the disc is ruptured by the knife. 6 figures.

  11. A piezoelectric micro control valve with integrated capacitive sensing for ambulant blood pressure waveform monitoring

    NASA Astrophysics Data System (ADS)

    Groen, Maarten S.; Wu, Kai; Brookhuis, Robert A.; van Houwelingen, Marc J.; Brouwer, Dannis M.; Lötters, Joost C.; Wiegerink, Remco J.

    2014-12-01

    We have designed and characterized a MEMS microvalve with built-in capacitive displacement sensing and fitted it with a miniature piezoelectric actuator to achieve active valve control. The integrated displacement sensor enables high bandwidth proportional control of the gas flow through the valve. This is an essential requirement for non-invasive blood pressure waveform monitoring based on following the arterial pressure with a counter pressure. Using the capacitive sensor, we demonstrate negligible hysteresis in the valve control characteristics. Fabrication of the valve requires only two mask steps for deep reactive ion etching (DRIE) and one release etch.

  12. 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.

  13. 49 CFR 178.348-4 - Pressure relief.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...—calories per gram (BTU/lb); Z = The compressibility factor for the vapor (if this factor is unknown, let Z... heat at constant pressure, in -calories per gram degree centigrade (BTU/lb °F.); and Cv = The specific heat at constant volume, in -calories per gram degree centigrade (BTU/lb °F.)....

  14. 49 CFR 178.348-4 - Pressure relief.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...—calories per gram (BTU/lb); Z = The compressibility factor for the vapor (if this factor is unknown, let Z... heat at constant pressure, in -calories per gram degree centigrade (BTU/lb °F.); and Cv = The specific heat at constant volume, in -calories per gram degree centigrade (BTU/lb °F.)....

  15. 49 CFR 178.348-4 - Pressure relief.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...—calories per gram (BTU/lb); Z = The compressibility factor for the vapor (if this factor is unknown, let Z... heat at constant pressure, in -calories per gram degree centigrade (BTU/lb °F.); and Cv = The specific heat at constant volume, in -calories per gram degree centigrade (BTU/lb °F.)....

  16. 49 CFR 178.348-4 - Pressure relief.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...—calories per gram (BTU/lb); Z = The compressibility factor for the vapor (if this factor is unknown, let Z... heat at constant pressure, in -calories per gram degree centigrade (BTU/lb °F.); and Cv = The specific heat at constant volume, in -calories per gram degree centigrade (BTU/lb °F.)....

  17. Obstruction of a Codman-Hakim programmable valve by a migrating pressure control cam.

    PubMed

    Shimizu, Satoru; Utsuki, Satoshi; Suzuki, Sachio; Oka, Hidehiro; Fujii, Kiyotaka

    2005-09-01

    Although the Codman-Hakim programmable valve is popular, several problems arising from its design have been described. The authors report an additional cause of shunt obstruction in the system. A 6-year-old girl who had received a ventriculoperitoneal shunt with the Codman-Hakim programmable valve system presented with worsening consciousness. The valve proved hard to flush, and emergency revision of the valve was performed. Examination of the extracted valve revealed that the pressure control cam had migrated into the outlet of the valve, thus causing the obstruction. A crack in the plastic housing surrounding the cam suggesting a past impact to the system was also revealed. These factors should thus be kept in mind as potential sources of obstruction of the valve system, especially in patients susceptible to episodes of head impact. PMID:16238082

  18. Pressure Regulators as Valves for Saving Compressed Air and their Influence on System Dynamics

    NASA Astrophysics Data System (ADS)

    Dvořák, Lukáš; Fojtášek, Kamil

    2015-05-01

    Pressure regulators in the field of pneumatic mechanisms can be used as valves for saving compressed air. For example it can be used to reduce the pressure when the piston rod is retracting unloaded and thus it is possible to save some energy. However the problem is that saving valve can significantly affect the dynamics of the pneumatic system. The lower pressure in the piston rod chamber causes extension of time for retraction of the piston rod. This article compare the air consumption experimentally determined and calculated, measured curves of pressure in cylinder chambers and piston speed when saving valve is set up differently.

  19. 40 CFR 265.1054 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 26 2014-07-01 2014-07-01 false Standards: Pressure relief devices in gas/vapor service. 265.1054 Section 265.1054 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) INTERIM STATUS STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND...

  20. 40 CFR 61.242-4 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 9 2014-07-01 2014-07-01 false Standards: Pressure relief devices in gas/vapor service. 61.242-4 Section 61.242-4 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Equipment Leaks...

  1. 40 CFR 265.1054 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 27 2013-07-01 2013-07-01 false Standards: Pressure relief devices in gas/vapor service. 265.1054 Section 265.1054 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) INTERIM STATUS STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND...

  2. 40 CFR 63.1030 - Pressure relief devices in gas and vapor service standards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 10 2011-07-01 2011-07-01 false Pressure relief devices in gas and vapor service standards. 63.1030 Section 63.1030 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National...

  3. 40 CFR 264.1054 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 26 2014-07-01 2014-07-01 false Standards: Pressure relief devices in gas/vapor service. 264.1054 Section 264.1054 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Air...

  4. 40 CFR 63.165 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 10 2014-07-01 2014-07-01 false Standards: Pressure relief devices in gas/vapor service. 63.165 Section 63.165 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES National Emission Standards...

  5. 40 CFR 60.482-4 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standards: Pressure relief devices in gas/vapor service. 60.482-4 Section 60.482-4 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Equipment Leaks of VOC in...

  6. 40 CFR 63.165 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 9 2011-07-01 2011-07-01 false Standards: Pressure relief devices in gas/vapor service. 63.165 Section 63.165 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES National Emission Standards...

  7. 40 CFR 63.1011 - Pressure relief devices in gas and vapor service standards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 10 2011-07-01 2011-07-01 false Pressure relief devices in gas and vapor service standards. 63.1011 Section 63.1011 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National...

  8. 40 CFR 60.482-4a - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Standards: Pressure relief devices in gas/vapor service. 60.482-4a Section 60.482-4a Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Equipment Leaks of VOC...

  9. 40 CFR 264.1054 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 27 2013-07-01 2013-07-01 false Standards: Pressure relief devices in gas/vapor service. 264.1054 Section 264.1054 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Air...

  10. 40 CFR 61.242-4 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 9 2013-07-01 2013-07-01 false Standards: Pressure relief devices in gas/vapor service. 61.242-4 Section 61.242-4 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Equipment Leaks...

  11. 40 CFR 65.111 - Standards: Pressure relief devices in gas/vapor service.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Standards: Pressure relief devices in gas/vapor service. 65.111 Section 65.111 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... device in gas/vapor service shall be operated with an instrument reading of less than 500 parts...

  12. An air-pressure-free elastomeric valve for integrated nucleic acid analysis by capillary electrophoresis

    NASA Astrophysics Data System (ADS)

    Jung, Wooseok; Barrett, Matthew; Brooks, Carla; Rivera, Andrew; Birdsell, Dawn N.; Wagner, David M.; Zenhausern, Frederic

    2015-12-01

    We present a new elastomeric valve for integrated nucleic acid analysis by capillary electrophoresis. The valve functions include metering to capture a designated volume of biological sample into a polymerase chain reaction (PCR) chamber, sealing to preserve the sample during PCR cycling, and transfer of the PCR-products and on-chip formamide post-processing for the analysis of DNA fragments by capillary gel electrophoresis. This new valve differs from prior art polydimethylsiloxane (PDMS) valves in that the valve is not actuated externally by air-pressure or vacuum so that it simplifies a DNA analysis system by eliminating the need for an air-pressure or vacuum source, and off-cartridge solenoid valves, control circuit boards and software. Instead, the new valve is actuated by a thermal cycling peltier assembly integrated within the hardware instrument that tightly comes in contact with a microfluidic cartridge for thermal activation during PCR, so that it spontaneously closes the valve without an additional actuator system. The valve has bumps in the designated locations so that it has a self-alignment that does not require precise alignment of a valve actuator. Moreover, the thickness of the new valve is around 600 μm with an additional bump height of 400 μm so that it is easy to handle and very feasible to fabricate by injection molding compared to other PDMS valves whose thicknesses are around 30-100 μm. The new valve provided over 95% of metering performance in filling the fixed volume of the PCR chamber, preserved over 97% of the sample volume during PCR, and showed very comparable capillary electrophoresis peak heights to the benchtop assay tube controls with very consistent transfer volume of the PCR-product and on-chip formamide. The new valve can perform a core function for integrated nucleic acid analysis by capillary electrophoresis.

  13. 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.

  14. Experiment and numerical simulation of cavitation performance on a pressure-regulating valve with different openings

    NASA Astrophysics Data System (ADS)

    Qu, W. S.; Tan, L.; Cao, S. L.; Xu, Y.; Huang, J.; Xu, Q. H.

    2015-01-01

    As a kind of widely used device in pipe system for pressure and flow rate regulating, the valve would experience cavitation in the case when a sharp pressure drop occurs, which will induce the energy loss, noise and vibration of pipeline system, and even operational accidents. The experiment on flow resistance coefficient of a DN600 pressure-regulating valve under operation conditions from 0% to 100% openings is conducted. Based on the RNG k-e turbulence model and the Rayleigh-Plesset cavitation equation, a set of computational model is developed to simulate the turbulent flow in the valve under operational conditions from 0% to 100% openings. The computational results of flow resistance coefficient are compared to the experimental data. And the numerical simulation is employed to predict the cavitation performance of the valve at different inlet flow conditions. The transient cavitating flow is calculated to reveal the time evolution of cavitation in the valve.

  15. Functional Changes of Diaphragm Type Shunt Valves Induced by Pressure Pulsation

    NASA Astrophysics Data System (ADS)

    Lee, Chong-Sun; Suh, Chang-Min; Ra, Young-Shin

    Shunt valves used to treat patients with hydrocephalus were tested to investigate influence of pressure pulsation on their flow control characteristics. Our focus was on flow dynamic and functional changes of the small and thin diaphragms in the valves that serve as the main flow control mechanism and are made from silicone elastomer. Firstly, pressure-flow control curves were compared under pulsed and steady flow (without pulsation) conditions. Secondly, functional changes of the valves were tested after a long-term continuous pulsation with a peristaltic pump. Thirdly, flushing procedures selectively conducted by neurosurgeons were simulated with a fingertip pressed on the dome of the valves. As 20cc/hr of flow rate was adjusted at a constant pressure, application of 40mmH2O of pressure pulse increased flow rate through shunt valves more than 60%. As a 90cm length silicone catheter was connected to the valve outlet, increase in the flow rate was substantially reduced to 17.5%. Pressure-flow control characteristics of some valves showed significant changes after twenty-eight days of pressure pulsation at 1.0 Hz under 50.0cc/hr of flow rate. Flushing simulation resulted in temporary decrease in the pressure level. It took three hours to fully recover the normal pressure-flow control characteristics after the flushing. Our results suggest that shunt valves with a thin elastic diaphragm as the main flow control mechanism are sensitive to intracranial pressure pulsation or pressure spikes enough to change their pressure-flow control characteristics.

  16. High-temperature, high-pressure oxygen metering valve

    NASA Technical Reports Server (NTRS)

    Christianson, Rollin C. (Inventor); Lycou, Peter P. (Inventor); Daniel, James A. (Inventor)

    1993-01-01

    A control valve includes a body defining a central cavity arranged between a fluid inlet and outwardly-diverging first and second fluid outlets respectively disposed in a common transverse plane. A valve member is arranged in the cavity for rotation between first and second operating positions where a transverse fluid passage through the valve member alternatively communicates the fluid inlet with one or the other of the fluid outlets. To minimize fluid turbulence when the valve member is rotated to an alternate operating position, the fluid passage has a convergent entrance for maintaining the passage in permanent communication with the fluid inlet as well as an oblong exit opening with spaced side walls for enabling the exit opening to temporarily span the first and second fluid outlets as the valve member is turned between its respective operating positions.

  17. 14 CFR 23.841 - Pressurized cabins.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... airplane must be able to maintain a cabin pressure altitude of not more than 15,000 feet in event of any... following valves, controls, and indicators, for controlling cabin pressure: (1) Two pressure relief valves... indicate to the pilot the pressure differential, the cabin pressure altitude, and the rate of change...

  18. High-temperature, high-pressure spherical segment valve provides quick opening

    NASA Technical Reports Server (NTRS)

    Giovannetti, A.; Himmelright, R.; Meyer, K.; Nitta, H.

    1964-01-01

    A hollow spherical segment valve with an eccentric permits non-rubbing closure and provides a means for gas-cooling the seal. The design allows quick opening at high temperatures and discharge pressures.

  19. Rankine cycle condenser pressure control using an energy conversion device bypass valve

    SciTech Connect

    Ernst, Timothy C; Nelson, Christopher R; Zigan, James A

    2014-04-01

    The disclosure provides a waste heat recovery system and method in which pressure in a Rankine cycle (RC) system of the WHR system is regulated by diverting working fluid from entering an inlet of an energy conversion device of the RC system. In the system, an inlet of a controllable bypass valve is fluidly coupled to a working fluid path upstream of an energy conversion device of the RC system, and an outlet of the bypass valve is fluidly coupled to the working fluid path upstream of the condenser of the RC system such that working fluid passing through the bypass valve bypasses the energy conversion device and increases the pressure in a condenser. A controller determines the temperature and pressure of the working fluid and controls the bypass valve to regulate pressure in the condenser.

  20. Alteration of the pressure setting of a Codman-Hakim programmable valve by a television.

    PubMed

    Utsuki, Satoshi; Shimizu, Satoru; Oka, Hidehiro; Suzuki, Sachio; Fujii, Kiyotaka

    2006-08-01

    A 7-year-old girl presented in semicomatose condition. She had received a ventriculoperitoneal shunt using a Codman-Hakim programmable valve. Head computed tomography demonstrated hydrocephalus and head radiography showed that the pressure setting of the shunt valve had changed to 60 mmH(2)O from 40 mmH(2)O. The pressure setting was returned to 40 mmH(2)O, and she was discharged because her clinical symptoms and hydrocephalus improved. One month later, she lost consciousness again and was transported to our hospital. Hydrocephalus and shunt valve pressure of 50 mmH(2)O were noted, and the pressure setting was returned to 40 mmH(2)O again. She was discharged without complications. We suspected that the valve pressure was caused by close contact with a television, because the patient tended to touch a television with her head during play. The valve pressure did not change after the television was placed on a high stand out of reach. We should recognize that there are many sources of weak magnetic fields that may influence a programmable valve in everyday life. PMID:16936463

  1. Skin microvascular and metabolic response to pressure relief maneuvers in people with spinal cord injury

    NASA Astrophysics Data System (ADS)

    Ramella-Roman, Jessica C.; Le, Du V. N.; Ghassemi, Pejhman; Nguyen, Thu A.; Lichy, Alison; Groah, Suzanne

    2013-02-01

    Clinician's recommendations on wheelchair pressure reliefs in the context of the high prevalence of pressure ulcers that occur in people with spinal cord injury is not supported by strong experimental evidence. Some data indicates that altered tissue perfusion and oxygenation occurring under pressure loads, such as during sitting, induce various pathophysiologic changes that may lead to pressure ulcers. Pressure causes a cascade of responses, including initial tissue hypoxia, which leads to ischemia, vascular leakage, tissue acidification, compensatory angiogenesis, thrombosis, and hyperemia, all of which may lead to tissue damage. We have developed an advanced skin sensor that allows measurement of oxygenation in addition to perfusion, and can be safely used during sitting. The sensor consists of a set of fiber optics probes, spectroscopic and Laser Doppler techniques that are used to obtain parameters of interest. The overriding goal of this project is to develop the evidence base for clinical recommendations on pressure reliefs. In this paper we will illustrate the experimental apparatus as well as some preliminary results of a small clinical trial conducted at the National Rehabilitation Hospital.

  2. A method for evaluating pressure locking and thermal binding of gate valves

    SciTech Connect

    Dogan, T.

    1996-12-01

    A method is described to evaluate the susceptibility of gate valves to pressure locking and thermal binding. Binding of the valve disc in the closed position due to high pressure water trapped in the bonnet cavity (pressure locking) or differential thermal expansion of the disk in the seat (thermal binding) represents a potential mechanism that can prevent safety-related systems from functioning when called upon. The method described here provides a general equation that can be applied to a given gate valve design and set of operating conditions to determine the susceptibility of the valve to fail due to disc binding. The paper is organized into three parts. The first part discusses the physical mechanisms that cause disc binding. The second part describes the mathematical equations. The third part discusses the conclusions.

  3. Numerical investigation of cavitation flow inside spool valve with large pressure drop

    NASA Astrophysics Data System (ADS)

    Deng, Jian; Pan, Dingyi; Xie, Fangfang; Shao, Xueming

    2015-12-01

    Spool valves play an important role in fluid power system. Cavitation phenomena happen frequently inside the spool valves, which cause structure damages, noise and lower down hydrodynamic performance. A numerical tools incorporating the cavitation model, are developed to predict the flow structure and cavitation pattern in the spool valve. Two major flow states in the spool valve chamber, i.e. flow-in and flow-out, are studies. The pressure distributions along the spool wall are first investigated, and the results agree well with the experimental data. For the flow-in cases, the local pressure at the throttling area drops much deeper than the pressure in flow-out cases. Meanwhile, the bubbles are more stable in flow-in cases than those in flow-out cases, which are ruptured and shed into the downstream.

  4. In vitro experiment of the pressure regulating valve for a glaucoma implant

    NASA Astrophysics Data System (ADS)

    Bae, Byunghoon; Kee, Hongseok; Kim, Seonho; Lee, Yeon; Sim, Taeseok; Kim, Yongkweon; Park, Kyihwan

    2003-09-01

    Glaucoma is an eye disease which is caused by abnormal high intraocular pressure (IOP) in the eye. If the condition of the patient becomes serious, the use of an implant device is recommended, which decreases the IOP compulsory. Active implants for glaucoma implants are capable of controlling the IOP actively and coping with the personal differences of patients. However, the conventional active valves for the glaucoma implant are not convenient for the patient and feasibility is not shown for the glaucoma treatment. In this paper, we propose, analyze, fabricate and experiment on the pressure regulating valve for the active implant. Based on the analysis, we carry out optimal design of the proposed valve. The in vitro experiments are performed extensively both using and not using a rabbit in open- and closed-loop pressure control. The various experimental results verify the possibility of the proposed valve for a glaucoma implant.

  5. 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.

  6. Promote Pressure Ulcer Healing in Individuals with Spinal Cord Injury Using an Individualized Cyclic Pressure-Relief Protocol

    PubMed Central

    Makhsous, Mohsen; Lin, Fang; Knaus, Evan; Zeigler, Mary; Rowles, Diane M.; Gittler, Michelle; Bankard, James; Chen, David

    2010-01-01

    Objective To evaluate whether an individualized cyclic pressure-relief protocol accelerates wound healing in wheelchair users with established pressure ulcers (PrUs). Design Randomized controlled study. Setting Spinal cord injury clinics. Participants Forty-four subjects, aged 18–79 years, with a Stage II or Stage III PrU, were randomly assigned to the control (n = 22) or treatment (n = 22) groups. Interventions Subjects in the treatment group used wheelchairs equipped with an individually adjusted automated seat that provided cyclic pressure relief, and those in the control group used a standard wheelchair. All subjects sat in wheelchairs for a minimum of 4 hours per day for 30 days during their PrU treatment. Main Outcome Measures Wound characteristics were assessed using the Pressure Ulcer Scale for Healing (PUSH) tool and wound dimensions recorded with digital photographs twice a week. Median healing time for a 30% healing relative to initial measurements, the percentage reduction in wound area, and the percentage improvement in PUSH score achieved at the end of the trial were compared between groups. Results At the end of 30 days, both groups demonstrated a general trend of healing. However, the treatment group was found to take significantly less time to achieve 30% healing for the wound measurement compared with the control group. The percentage improvement of the wound area and PUSH scores were greater in using cyclic seating (45.0 ± 21.0, P < .003; 29.9 ± 24. 6, P < .003) compared with standard seating (10.2 ± 34.9, 5.8 ± 9.2). Conclusions The authors' findings show that cyclically relieving pressure in the area of a wound for seated individuals can greatly aid wound healing. The current study provides evidence that the individualized cyclic pressure-relief protocol helps promote pressure wound healing in a clinical setting. The authors concluded that the individualized cyclic pressure relief may have substantial benefits in accelerating the healing

  7. Faulting processes at high fluid pressures: An example of fault valve behavior from the Wattle Gully Fault, Victoria, Australia

    NASA Astrophysics Data System (ADS)

    Cox, Stephen F.

    1995-07-01

    The internal structures of the Wattle Gully Fault provide insights about the mechanics and dynamics of fault systems exhibiting fault valve behavior in high fluid pressure regimes. This small, high-angle reverse fault zone developed at temperatures near 300°C in the upper crust, late during mid-Devonian regional crustal shortening in central Victoria, Australia. The Wattle Gully Fault forms part of a network of faults that focused upward migration of fluids generated by metamorphism and devolatilisation at deeper crustal levels. The fault has a length of around 800 m and a maximum displacement of 50 m and was oriented at 60° to 80° to the maximum principal stress during faulting. The structure was therefore severely misoriented for frictional reactivation. This factor, together with the widespread development of steeply dipping fault fill quartz veins and associated subhorizontal extension veins within the fault zone, indicates that faulting occurred at low shear stresses and in a near-lithostatic fluid pressure regime. The internal structures of these veins, and overprinting relationships between veins and faults, indicate that vein development was intimately associated with faulting and involved numerous episodes of fault dilatation and hydrothermal sealing and slip, together with repeated hydraulic extension fracturing adjacent to slip surfaces. The geometries, distribution and internal structures of veins in the Wattle Gully Fault Zone are related to variations in shear stress, fluid pressure, and near-field principal stress orientations during faulting. Vein opening is interpreted to have been controlled by repeated fluid pressure fluctuations associated with cyclic, deformation-induced changes in fault permeability during fault valve behavior. Rates of recovery of shear stress and fluid pressure after rupture events are interpreted to be important factors controlling time dependence of fault shear strength and slip recurrence. Fluctuations in shear stress

  8. NASA Helps Industry Relieve Pressure Safely

    NASA Technical Reports Server (NTRS)

    2003-01-01

    In many industrial applications, pressure relief valves (PRV) perform the critical function of safely releasing pressure before potentially damaging build-ups occur. Conventional relief valves, however, have proven unstable, leading to premature wear and devasting consequences. A high-performance pressure relief valve, the PRV95, now being manufactured my Marotta Scientific Controls, Inc., of Montville, NJ, provides the answer to premature wear and instability. Using an improved valve design developed under a NASA Small Business Innovation Research Program (SBIR) contract from John C. Stennis Space Center (SSC), Marotta's PRV95 pressure relief valve provides stability over the entire operational range, from fully closed to fully open. The valve employs upstream control for valve positioning, that makes the valve more stable and affords excellent repeatability with minimal lag time. 'It opens and closes softly, and does not oscillate or generate hard impacts; oscillation can result in a hard impact pressure release, which can lead to an explosion in the presence of oxygen,' says Bill St. Cyr, Chief of Test Technology Branch at Stennis Space Center. Marotta's PRV95 design is also unique in its ability to maintain a seal near the set point of the relief limit. Typically, relief valves seal tightly up to 90% of set point and then reseat when pressure is reduced to 85% of set point. The PRV95 technology maintains seal integrity until 98% of set point and will reseat a 95-97% of set point. This allows the operator to protect his system while not exceeding its limits.

  9. Radial-directed fluid-pressure-loaded all-metal-sealed gate valve

    DOEpatents

    Batzer, Thomas H.

    1992-01-01

    A large diameter gate valve uses a radially directed fluid pressure loaded all metal seal formed by engaging and disengaging a fixed and a moveable seal element. The fixed element is formed of a circular flange which contains a pressure chamber with a deformable wall, and is mounted to the valve body. The moving seal element contains an annular recess which mates with the circular flange, and is carried on a moveable sub-frame which moves on a frame fixed in the valve body. The valve opening defines an axis in a first direction, and the sub-frame moves through the valve body in a second direction which is substantially perpendicular to the first direction. The sub-frame and moveable seal element move in the second direction until the moveable element reaches a stop mounted in the valve body at which position the moveable element is aligned with but spaced apart from the fixed element. As the sub-frame continues to move in the second direction, the moveable element is forced to move toward and engage the fixed element. The pressure chamber in the flange is then pressurized to complete the seal.

  10. A study of the fluid-dynamic pressure fields on compressor reed valves

    NASA Astrophysics Data System (ADS)

    Hunt, R. D.

    1985-12-01

    The flow induced pressure field in a reed valve arrangement was analytically predicted and experimentally measured for steady state conditions. The flow was found to be supersonic in nature with an imbedded shock for all but the lowest pressure runs. The analytic method used one-dimensional isentropic and normal shock relations. The technique provides a good first look at the nature of the flow and is compatible for use on a small computer system. The experimental data was obtained by using an idealized reed valve model. The data acquisition system was computerized and used a scanivalve system to measure the pressure in the valve model. Circular, square, and rectangular valve plate geometries were investigated. The inlet was circular for all cases. Flow visualization oil was also used in a qualitative approach to determine the location and shape of the shock in the flow. The pressure measurements and the flow visualization showed the shock to be circular for all geometries and pressures tested. At high total pressure runs the valve plate began vibrating and the shock location became smeared suggesting the shock was also oscillating.

  11. Innovative, High-Pressure, Cryogenic Control Valve: Short Face-to-Face, Reduced Cost

    NASA Technical Reports Server (NTRS)

    Wilkes, Karlin; Larsen, Ed; McCourt, Jackson

    2004-01-01

    A control valve that can throttle high pressure cryogenic fluid embodies several design features that distinguish it over conventional valves designed for similar applications. Field and design engineers worked together to create a valve that would simplify installation, trim changes, and maintenance, thus reducing overall cost. The seals and plug stem packing were designed to perform optimally in cryogenic temperature ranges. Unlike conventional high-pressure cryogenic valves, the trim size can be changed independent of the body. The design feature that provides flexibility for changing the trim is a split body. The body is divided into an upper and a lower section with the seat ring sandwiched in between. In order to maintain the plug stem packing at an acceptable sealing temperature during cryogenic service, heat-exchanging fins were added to the upper body section (see figure). The body is made of stainless steel.

  12. Problem: Heart Valve Regurgitation

    MedlinePlus

    ... Pressure High Blood Pressure Tools & Resources Stroke More Problem: Heart Valve Regurgitation Updated:May 26,2016 What ... content was last reviewed May 2016. Heart Valve Problems and Disease • Home • About Heart Valves • Heart Valve ...

  13. Problem: Heart Valve Stenosis

    MedlinePlus

    ... Pressure High Blood Pressure Tools & Resources Stroke More Problem: Heart Valve Stenosis Updated:Aug 10,2016 About ... content was last reviewed May 2016. Heart Valve Problems and Disease • Home • About Heart Valves • Heart Valve ...

  14. Numerical Simulation of Flow-Induced Noise in High Pressure Reducing Valve

    PubMed Central

    Wei, Lin; Zhu, Guorong; Qian, Jinyuan; Fei, Yang; Jin, Zhijiang

    2015-01-01

    The main objective of this paper is to study the characteristics of flow-induced noise in high pressure reducing valve (HPRV) and to provide some guidance for noise control. Based on computational fluid dynamics (CFD), numerical method was used to compute flow field. Ffowcs Williams and Hawkings Model was applied to obtain acoustic signals. The unsteady flow field shows that noise sources are located at the bottom of plug for valve without perforated plate, and noise sources are behind the plate for valve with perforated plate. Noise directivity analysis and spectrum characteristics indicate that the perforated plate could help to reduce noise effectively. Inlet pressure has great effects on sound pressure level (SPL). The higher inlet pressure will lead to larger SPL at high frequency. When the maximum Ma is close to 1, SPL at low frequency becomes very high. PMID:26061396

  15. Transient hydrodynamics of in-line valves in viscoelastic pressurized pipes: long-period analysis

    NASA Astrophysics Data System (ADS)

    Meniconi, Silvia; Brunone, Bruno; Ferrante, Marco; Massari, Christian

    2012-07-01

    The literature contains few reports devoted to the analysis of the effects of a partially closed in-line valve on the characteristics of transients in viscoelastic pressurized pipes. In this paper a contribution to the analysis of the long-period behavior of pressure is offered from both the experimental and numerical modeling point of view. In the first part, laboratory tests and the related results—noticeably extensive with respect to the existing literature—are examined. More precisely, the dependance of the damping of the dimensionless pressure maximum values on the initial conditions and in-line valve local head loss coefficient is shown. In the second part, a 1-D numerical model is developed by determining its parameters within a physically based procedure. Model parameters are obtained by considering transients in a constant-diameter pipe (single pipe) and then exported to the case of pipes with a partially closed in-line valve (in-line valve pipe). Moreover, particular attention is devoted to the modalities of specifying boundary conditions. In particular, the quasi-steady-state approach is followed for determining the transient local head loss due to the partially closed in-line valve and the actual supply conditions and characteristics of the maneuver are taken into account. Finally, the effect of unsteady friction and viscoelasticity is examined in both single and in-line valve pipes.

  16. Adding a custom made pressure release valve during air enema for intussusception: A new technique

    PubMed Central

    Ahmed, Hosni Morsi; Ahmed, Osama; Ahmed, Refaat Khodary

    2015-01-01

    Background: Non-surgical reduction remains the first line treatment of choice for intussusception. The major complication of air enema reduction is bowel perforation. The authors developed a custom made pressure release valve to be added to portable insufflation devices, delivering air at pressures accepted as safe for effective reduction of intussusception in children under fluoroscopic guidance. The aim of this study was to develop a custom made pressure release valve that is suitable for the insufflation devices used for air enema reduction of intussusception and to put this valve into regular clinical practice. Materials and Methods: An adjustable, custom made pressure release valve was assembled by the authors using readily available components. The valve was coupled to a simple air enema insufflation device. The device was used for the trial of reduction of intussusception in a prospective study that included 132 patients. Results: The success rate for air enema reduction with the new device was 88.2%. The mean pressure required to achieve complete reduction was 100 mmHg. The insufflation pressure never exceeded the preset value (120 mmHg). Of the successful cases, 58.3% were reduced from the first attempt while 36.1% required a second insufflation. Only 5.55% required a third insufflation to complete the reduction. In cases with unsuccessful pneumatic reduction attempt (18.1%), surgical treatment was required. Surgery ranged from simple reduction to resection with a primary end to end anastomosis. No complications from air enema were recorded. Conclusions: The authors recommend adding pressure release valves to ensure safety by avoiding pressure overshoot during the procedure. PMID:26712286

  17. Valve assembly for use with high temperature and high pressure fluids

    DOEpatents

    De Feo, Angelo

    1982-01-01

    The valve assembly for use with high temperature and high pressure fluids has inner and outer spaced shells and a valve actuator support of inner and outer spaced members which are connected at their end portions to the inner and outer shells, respectively, to extend substantially normal to the longitudinal axis of the inner shell. A layer of resilient heat insulating material covers the outer surfaces of the inner shell and the inner actuator support member and is of a thickness to only occupy part of the spaces between the inner and outer shells and inner and outer actuator support members. The remaining portion of the space between the inner and outer shells and the space between the inner and outer members is substantially filled with a body of castable, rigid refractory material. A movable valve member is disposed in the inner shell. A valve actuator assembly is supported in the valve actuator support to extend into the inner shell for connection with the movable valve member for movement of the movable valve member to positions from a fully open to a fully closed position to control flow of fluid through the inner shell. An anchor mneans is disposed adjacent opposite sides of the axis of the valve actuator support and attached to the inner shell so that relative radial movement between the inner and outer shell is permitted by the layer of resilient heat insulating material and relative longitudinal movement of the inner shell to the outer shell is permitted in opposite directions from the anchor means to thereby maintain the functional integrity of the movable valve member by providing an area of the inner shell surrounding the movable valve member longitdinally stationary, but at the same time allowing radial movement.

  18. Safety Testing of Left Ventricular Vent Valves.

    PubMed

    Gavin, Caroline; Coblentz, John; Acsell, Jeffrey R; Shackelford, Anthony G; Sistino, Joseph J

    2015-03-01

    Vent vacuum relief valves (VRVs) are used to limit the negative pressure at the ventricular vent catheter tip as well as prevent reversal of blood flow and prevention of air embolism. The purpose of this study was to evaluate the performance of three commercially available ventricular vent valves. The negative pressure at which the vent valve opened was measured at the valve inlet using high-fidelity pressure transducers. Also, the flow rate at which air entrainment occurred due to valve opening was recorded. Using a 51.5 cm column of saline, the resistance for each valve was calculated. The mean ± SD opening negative pressures were -231.3 ± 35.2 mmHg for the Quest Medical valve, -219.8 mmHg ± 17.2 for the Sorin valve, and -329.6 · 38.0 mmHg for the Terumo valve. The red Quest Medical valve opened at a lower flow (1.44 ± .03 L/min) than the dark blue Sorin valve (2.93 ± .01 L/min) and light blue LH130 Terumo valve (2.36 ± .02 L/min). The Sorin valve had the least resistance of 34.1 dyn-s/cm, followed by the Terumo LH130 valve resistance of 58.1 dyn·s/cm5, and the Quest Medical VRV-II valve with a resistance of 66.5 dyn·s/cm. We found that the valves are significantly different in the negative pressure generated. Understanding the limitations of these devices is important to reduce the occurrence of adverse events associated with venting and to select the best device for a specific clinical application. PMID:26390676

  19. 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.

  20. A Respiratory Airway-Inspired Low-Pressure, Self-Regulating Valve for Drip Irrigation

    NASA Astrophysics Data System (ADS)

    Wang, Ruo-Qian; Winter, Amos G.; GEAR Lab Team

    2015-11-01

    One of the most significant barriers to achieving large-scale dissemination of drip irrigation is the cost of the pump and power system. An effective means of reducing power consumption is by reducing pumping pressure. The principle source of pressure drop in a drip system is the high flow resistance in the self-regulating flow resistors installed at the outlets of the pips, which evenly distribute water over a field. Traditional architectures require a minimum pressure of ~1 bar to maintain a constant flow rate; our aim is to reduce this pressure by 90% and correspondingly lower pumping power to facilitate the creation of low-cost, off-grid drip irrigation systems. This study presents a new Starling resistor architecture that enables the adjustment of flow rate with a fixed minimum pressure demand of ~0.1 bar. A Starling resistor is a flexible tube subjected to a transmural pressure, which collapses the tube to restrict flow. Our design uses a single pressure source to drive flow through the flexible tube and apply a transmural pressure. Flow into the flexible tube is restricted with a needle valve, to increase the transmural pressure. Using this device, a series of experiments were conducted with different flexible tube diameters, lengths and wall thickness. We found that the resistance of the needle valve changes flow rate but not the minimum transmural pressure required to collapse the tube. A lumped-parameter model was developed to capture the relationships between valve openings, pressure, and flow rates.

  1. Polymeric check valve with an elevated pedestal for precise cracking pressure in a glaucoma drainage device.

    PubMed

    Park, Chang-Ju; Yang, Dong-Seong; Cha, Jung-Joon; Lee, Jong-Hyun

    2016-02-01

    This paper presents the design, fabrication, and characterization of a polymeric micro check valve for a glaucoma drainage device (GDD) featuring the precise regulation of intraocular pressure (IOP) and effective aqueous humor turnover (AHT). The pedestal, slightly elevated by selective coating of a parylene C film, induces pre-stress in the thin valve membrane, which enhances the predictability of the cracking pressure of the GDD. The proposed GDD comprises a cannula and a normally closed polymeric micro check valve, which are made of PDMS, a biocompatible polymer, with three layers: top (cover), intermediate (thin valve membrane), and bottom (base plate). A feedback channel, located between the top and intermediate layers, prevents reverse flow by feeding the pressure of the outlet channel back to the thin valve membrane. To achieve a precise cracking pressure and sufficient drainage of humor for humans, the thicknesses of the valve membrane and parylene C film are designed to be 58 μm and 1 μm, respectively, which are confirmed using a COMSOL simulation. The experimental results show that the cracking pressure of the fabricated GDD lies within the range of normal IOP (1.33-2.67 kPa). The forward flow rate (drainage rate), 4.3 ± 0.9 μL/min at 2.5 kPa, is adequate to accommodate the rate of AHT in a normal human eye (2.4 ± 0.6 μL/min). The reverse flow was not observed when a hydrostatic pressure of up to 4 kPa was applied to the outlet and the feedback channel. PMID:26864969

  2. Spinal Cord Injury and Pressure Ulcer Prevention: Using Functional Activity in Pressure Relief

    PubMed Central

    Stinson, May; Gillan, Cathy; Morton, Julie; Gardner, Evie; Sprigle, Stephen

    2013-01-01

    Background. People with spinal cord injury (SCI) are at increased risk of pressure ulcers due to prolonged periods of sitting. Concordance with pressure relieving movements is poor amongst this population, and one potential alternative to improve this would be to integrate pressure relieving movements into everyday functional activities. Objectives. To investigate both the current pressure relieving behaviours of SCI individuals during computer use and the application of an ergonomically adapted computer-based activity to reduce interface pressure. Design. Observational and repeated measures design. Setting. Regional Spinal Cord Injury Unit. Participants. Fourteen subjects diagnosed with SCI (12 male, 2 female). Intervention.Comparing normal sitting to seated movements and induced forward reaching positions. Main Outcome Measures. Interface pressure measurements: dispersion index (DI), peak pressure index (PPI), and total contact area (CA). The angle of trunk tilt was also measured. Results. The majority of movements yielded less than 25% reduction in interface pressure compared to normal sitting. Reaching forward by 150% of arm length during an adapted computer activity significantly reduced DI (P < 0.05), angle of trunk tilt (p<0.05), and PPI for both ischial tuberosity regions (P < 0.001) compared to normal sitting. Conclusion. Reaching forward significantly redistributed pressure at the seating interface, as evidenced by the change in interface pressures compared to upright sitting. PMID:23691301

  3. Numerical simulation analysis and optimum design for combined type pressure reducing valves

    NASA Astrophysics Data System (ADS)

    Gou, D. M.; Guo, P. C.; Zheng, X. B.; Luo, X. Q.; Sun, L. G.

    2016-05-01

    Pressure reducing valve is an extremely significant equipment of energy dissipation for the water supply by gravity with pressure reducing technology in hydropower stations, and which has a pronounced effect on the normal technical water supply even safety operation for the hydropower units. A three-dimensional numerical calculation of flow field and cavitation characteristics towards a combined type pressure reducing valves was carried out based on the system of technical water supply in this paper. The numerical results show that the investigated valve could meet the requirements of technological supply water pressure and great pressure loss was caused when the water flow was accelerated by narrow overflowing section between throttling cone and valve seat. At working operation, obvious cavitation phenomenon was observed on the surface of throttling cone, and the maximum volume fraction of vapor reached 0.537%. Based on above researches, this paper introduces an optimization model for profile line design of throttling cone. The optimal results show that the cavitation performance is effectively improved with identical pressure drop compared with original results.

  4. What is the ideal initial valve pressure setting in neonates with ventriculoperitoneal shunts?

    PubMed

    Korinth, Marcus C; Gilsbach, J M

    2002-04-01

    In order to determine the optimal valve pressure setting during the first weeks in neonates after implantation of programmable Hakim valves and to analyze the benefits and possible side effects of a new treatment protocol in this age group, we performed this prospective study. In 20 consecutive newborns less than 5 weeks of age with hydrocephalus due to various etiologies, a ventriculoperitoneal shunt with a programmable Hakim valve at an extremely low initial valve pressure setting of 30-40 mm H(2)O was implanted. This "overdrainage" was maintained, monitored by regular clinical examination and transcranial ultrasonographic imaging, until the wound healing was uneventfully completed and the permanent valve pressure setting of 100-120 mm H(2)O was chosen. In this age group, which is prone to specific noninfectious shunt complications like wound breakdown, cerebrospinal fluid (CSF) fistula and subcutaneous CSF collections, none of these complications were seen, nor were there any persisting overdrainage phenomena on transcranial ultrasonography. Initial, temporary "overdrainage" represents a simple, useful and risk-free therapy in neonates with programmable shunts which might lower the incidence of typical noninfectious complications in this age group. PMID:12006750

  5. Variable force solenoid pressure control for an automatic transmission

    SciTech Connect

    Lemieux, G.E.

    1989-05-30

    This patent describes a hydraulic pressure control circuit for an automatic transmission having fluid pressure operated clutch and brake servo. The controlling transmission consists of: a pump and a main pressure regulator valve means for establishing a regulated pressure in the control circuit; a variable force solenoid valve means for developing a pressure proportional to engine torque including a variable force solenoid connected to pressure regulating portions of the torque proportional pressure; a torque signal passage connecting to the variable force solenoid valve means with the pressure regulator valve means whereby the regulated pressure level maintained by the main regulator valve means is controlled in response to changes in the torque proportional pressure; and a variable force solenoid pressure relief valve means communicating with the torque signal passage and with the variable force solenoid valve means whereby the variable force solenoid valve means is adapted to regulate and to develop a pressure of reduced value relative to the regulated pressure of the main pressure regulator valve means as it establishes the torque proportional pressure, the solenoid pressure relief valve means comprising a pressure regulating valve spool, a valve chamber receiving the spool. The spool and the valve chamber having registering valve lands, a valve spring on one side of the spool urging the spool in one direction, a first pressure area on the pool being exposed to the torque proportional pressure, a second pressure area on the valve spool exposed to the pressure of reduced value whereby the spring, the pressure of reduced value and the torque proportional pressure establish a balanced force on the spool.

  6. Pressure disequilibria induced by rapid valve closure in noble gas extraction lines

    NASA Astrophysics Data System (ADS)

    Morgan, Leah E.; Davidheiser-Kroll, Brett

    2015-06-01

    Pressure disequilibria during rapid valve closures can affect calculated molar quantities for a range of gas abundance measurements (e.g., K-Ar geochronology, (U-Th)/He geochronology, noble gas cosmogenic chronology). Modeling indicates this effect in a system with a 10 L reservoir reaches a bias of 1% before 1000 pipette aliquants have been removed from the system, and a bias of 10% before 10,000 aliquants. Herein we explore the causes and effects of this problem, which is the result of volume changes during valve closure. We also present a solution in the form of an electropneumatic pressure regulator that can precisely control valve motion. This solution reduces the effect to ˜0.3% even after 10,000 aliquants have been removed from a 10 L reservoir.

  7. Quick-Disconnect Valves For Modular Fluid Systems

    NASA Technical Reports Server (NTRS)

    Fluger, Charles; Rexer, Rudolf; Roebelen, George J.; Green, John B., Jr.

    1988-01-01

    Maintainable valves being developed for use as interfaces between modules or other separable components in maintainable fluid systems. Pair of valves joins two plumbing subsystems, connected to or disconnected from each other and enabling either or both to be isolated upon disconnection. Relief valve built into cartridge of maintainable valve, cartridge removes for replacement or inspection. New valves designed for temperature-regulating equipment aboard space station, used with or without modifications in variety of liquid and low-pressure-gas systems on Earth.

  8. Microcracking during stress-relief of polycrystalline ice formed at high pressure

    NASA Astrophysics Data System (ADS)

    Meglis, Irene L.; Gagnon, R. E.; Young, R. P.

    To study microcracking in a brittle material in response to stress-relief, samples of polycrystalline ice were frozen under hydrostatic pressures up to 19 MPa and subsequently decompressed. Eight cylindrical samples (approximately 56 mm in diameter and 120 mm long) were made by freezing a slurry of crushed ice and degassed water inside a clear Teflon jacket. Four additional tests were done by reloading samples which were previously unloaded, allowing them to re-equilibrate, and then unloading again. Tests were filmed through windows in the confining cell. Acoustic emissions were monitored in some samples. When the stress was released, intense cracking occurred for approximately 0.4 seconds and then tapered off. Thin sections showed that the stress-relief cracks were approximately equal to the facet size (<5 mm), were primarily along grain boundaries, and were distributed throughout the samples with no obvious preferred orientation. Within a few hours of unloading, grain boundaries became cloudy, possibly a result of air trapped at the grain surfaces. Preliminary results from further tests indicate that this air plays a significant role in crack nucleation.

  9. A novel mechanism of cochlear excitation during simultaneous stimulation and pressure relief through the round window

    PubMed Central

    Weddell, Thomas D.; Yarin, Yury M.; Drexl, Markus; Russell, Ian J.; Elliott, Stephen J.; Lukashkin, Andrei N.

    2014-01-01

    The round window (RW) membrane provides pressure relief when the cochlea is excited by sound. Here, we report measurements of cochlear function from guinea pigs when the cochlea was stimulated at acoustic frequencies by movements of a miniature magnet which partially occluded the RW. Maximum cochlear sensitivity, corresponding to subnanometre magnet displacements at neural thresholds, was observed for frequencies around 20 kHz, which is similar to that for acoustic stimulation. Neural response latencies to acoustic and RW stimulation were similar and taken to indicate that both means of stimulation resulted in the generation of conventional travelling waves along the cochlear partition. It was concluded that the relatively high impedance of the ossicles, as seen from the cochlea, enabled the region of the RW not occluded by the magnet, to act as a pressure shunt during RW stimulation. We propose that travelling waves, similar to those owing to acoustic far-field pressure changes, are driven by a jet-like, near-field component of a complex pressure field, which is generated by the magnetically vibrated RW. Outcomes of research described here are theoretical and practical design principles for the development of new types of hearing aids, which use near-field, RW excitation of the cochlea. PMID:24501274

  10. Development of a fluid friction control valve for pressure letdown in hot dirty gas streams

    SciTech Connect

    Novack, M.

    1990-09-01

    Control valves required for pressure letdown service in future commercial coal conversion plants will be subjected to severe service at a temperature and pressure as high as 1800{degree}F and 800 psig, respectively, in a gaseous environment leading to valve erosion and corrosion. This report describes the design and development of a fluid friction control valve (FFCV) for these severe pressure reduction applications. The FFCV is designed to dissipate friction-induced energy losses uniformly over an extended surface flow path, and thus eliminate pressure reduction taking place in a single-step process. This important feature of the FFCV, by which the fluid mixture velocity is significantly reduced, has the potential of minimizing or even eliminating the problems associated with conventional-type control valves. The component parts of the FFCV exposed to the hot gas flow stream were fabricated from Inconel Alloy 625, a high strength nickel-chromium-molybdenum alloy used in high temperature corrosive environments. The FFCV underwent combined parametric and endurance tests at temperatures and pressures of up to 1500 F and 1000 psig, respectively, at gas stream flowrates of up to 100 lb/hr. To simulate abrasive ash/char particulate as found in conversion plant gas streams, three forms of silica powders were used. Over the course of 53 test runs, the FFCV was subjected to a cumulative endurance test duration of 164 hours, of which 55 hours were with silica particulate in the gas stream. During these tests the FFCV maintained its structural integrity and operated without clogging or jamming. Upon completion of testing, examination of the internal valve surfaces exposed to the gas stream showed no discernable erosion. 1 ref., 23 figs., 3 tabs.

  11. Nonlinear fluid/structure interaction relating a rupture-disc pressure-relief device. [LMFBR

    SciTech Connect

    Hsieh, B.J.; Kot, C.A.; Shin, Y.W.; Youngdahl, C.K.

    1983-01-01

    Rupture disc assemblies are used in piping network systems as a pressure-relief device. The reverse-buckling type is chosen for application in a liquid metal fast breeder reactor. This assembly is used successfully in systems in which the fluid is highly compressible, such as air; the opening up of the disc by the knife setup is complete. However, this is not true for a liquid system; it had been observed experimentally that the disc may open up only partially or not at all. Therefore, to realistically understand and represent a rupture disc assembly in a liquid environment, the fluid-structure interactions between the liquid medium and the disc assembly must be considered. The methods for analyzing the fluid and the disc and the mechanism interconnecting them are presented. The fluid is allowed to cavitate through a column-cavitation model and the disc is allowed to become plastically deformed through the classic Von Mises' yield criteria, when necessary.

  12. 49 CFR 178.337-9 - Pressure relief devices, piping, valves, hoses, and fittings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... must not be capable of causing any adverse chemical reaction with the cargo tank lading in the event of... citations affecting § 178.337-9, see the List of CFR Sections Affected which appears in the Finding...

  13. 49 CFR 178.337-9 - Pressure relief devices, piping, valves, hoses, and fittings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... causing any adverse chemical reaction with the cargo tank lading in the event of leakage. The unit... affecting § 178.337-9, see the List of CFR Sections Affected which appears in the Finding Aids section...

  14. 49 CFR 178.337-9 - Pressure relief devices, piping, valves, hoses, and fittings.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... causing any adverse chemical reaction with the cargo tank lading in the event of leakage. The unit... affecting § 178.337-9, see the List of CFR Sections Affected, which appears in the Finding Aids section...

  15. 49 CFR 178.338-8 - Pressure relief devices, piping, valves, and fittings.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    .... Where copper tubing is permitted, joints shall be brazed or be of equally strong metal union type. The melting point of the brazing materials may not be lower than 1000 °F. The method of joining tubing may not reduce the strength of the tubing, such as by the cutting of threads. (3) Each hose coupling must...

  16. 49 CFR 178.337-9 - Pressure relief devices, piping, valves, hoses, and fittings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... causing any adverse chemical reaction with the cargo tank lading in the event of leakage. The unit... affecting § 178.337-9, see the List of CFR Sections Affected, which appears in the Finding Aids section...

  17. 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

    ....'' Existing Coast Guard regulations regarding the allowable stress factors for type B and type C independent... promulgated regulations on allowable stress factors on May 3, 1979. CG-ENG Policy Letter 04-12 establishes... advanced techniques, the IMO standards for allowable stress factors provide a level of safety...

  18. Recommendations on frequently encountered relief requests

    SciTech Connect

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

    1992-01-01

    This paper is based on the review of a large database of requests for relief from enservice testing (1ST) requirements for pumps and valves. From the review, the paper identifies areas where enhancements to either the relief request process or the applicable test codes can improve IST of pumps and valves. Certain types of requests occur frequently. The paper examines some frequent requests and considers possible changes to the requirements to determine if the frequent requests can be eliminated. Recommended changes and their bases will be discussed. IST of safety-related pumps and valves at commercial nuclear power plants is done according to the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (the Code), Section XI. Because of the design and function of some safety systems in nuclear plants, performing Code testing of certain pumps and valves is impractical or a hardship without a compensating increase in the level of safety. Deviations from the Code are allowed by law, as reviewed and approved by the United States Nuclear Regulatory Commission (NRC), through the relief request process. Because of similarities in plant design and system function, many problems encountered in testing components are similar from plant to plant. Likewise, there are often common problems associated with test methods or equipment. Therefore, many relief requests received by the NRC from various plants are similar. Identifying and addressing the root causes for these common requests will greatly improve IST.

  19. Recommendations on frequently encountered relief requests

    SciTech Connect

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

    1992-09-01

    This paper is based on the review of a large database of requests for relief from enservice testing (1ST) requirements for pumps and valves. From the review, the paper identifies areas where enhancements to either the relief request process or the applicable test codes can improve IST of pumps and valves. Certain types of requests occur frequently. The paper examines some frequent requests and considers possible changes to the requirements to determine if the frequent requests can be eliminated. Recommended changes and their bases will be discussed. IST of safety-related pumps and valves at commercial nuclear power plants is done according to the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (the Code), Section XI. Because of the design and function of some safety systems in nuclear plants, performing Code testing of certain pumps and valves is impractical or a hardship without a compensating increase in the level of safety. Deviations from the Code are allowed by law, as reviewed and approved by the United States Nuclear Regulatory Commission (NRC), through the relief request process. Because of similarities in plant design and system function, many problems encountered in testing components are similar from plant to plant. Likewise, there are often common problems associated with test methods or equipment. Therefore, many relief requests received by the NRC from various plants are similar. Identifying and addressing the root causes for these common requests will greatly improve IST.

  20. Nonlinear fluid/structure interaction relating a rupture-disc pressure-relief device

    SciTech Connect

    Hsieh, B.J.; Kot, C.A.; Shin, Y.W.; Youngdahi, C.K.

    1983-01-01

    Rupture disc assemblies are used in piping network systems as pressure-relief devices. The reverse-buckling type discs are chosen for application in heat transport systems of liquid metal fast breeder reactors. When the pressure on the disc is of sufficient magnitude and duration, the disc develops large displacement, is consequently torn open by a cutting-knife setup and thus relieves the excess pressure. Such disc assemblies are used very successfully in systems in which the fluid is highly compressible, e.g., air; the opening of the disc by the knife setup is complete. However, this is not true for a liquid system; in this case it has been observed experimentally that the disc may open up only partially or not at all. Therefore, to understand and realistically represent a rupture disc assembly in a liquid environment, the fluid-structure interactions between the liquid medium and the disc assembly must be considered. In this paper, methods for analyzing the fluid and the disc and the mechanism interconnecting them are presented. When necessary the fluid is allowed to cavitate through a column separation model and the disc can become plastically deformed using the classic Von Mises' yield criteria.