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Sample records for liquid relief valves

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

    Code of Federal Regulations, 2012 CFR

    2012-07-01

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

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

    Code of Federal Regulations, 2013 CFR

    2013-07-01

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

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

    Code of Federal Regulations, 2011 CFR

    2011-07-01

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

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

    Code of Federal Regulations, 2014 CFR

    2014-07-01

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

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

    Code of Federal Regulations, 2010 CFR

    2010-07-01

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

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. 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.

  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... comply with paragraphs (b)(1) and (b)(2) of this section. Pumps, valves, connectors, and agitators...

  13. 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... shall comply with paragraphs (b)(1) and (b)(2) of this section. Pumps, valves, connectors, and...

  14. 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

    ... 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... comply with paragraphs (b)(1) and (b)(2) of this section. Pumps, valves, connectors, and agitators...

  15. 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... shall comply with paragraphs (b)(1) and (b)(2) of this section. Pumps, valves, connectors, and...

  16. 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... shall comply with paragraphs (b)(1) and (b)(2) of this section. Pumps, valves, connectors, and...

  17. 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... comply with paragraphs (b)(1) and (b)(2) of this section. Pumps, valves, connectors, and agitators...

  18. 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... shall comply with paragraphs (b)(1) and (b)(2) of this section. Pumps, valves, connectors, and...

  19. 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... shall comply with paragraphs (b)(1) and (b)(2) of this section. Pumps, valves, connectors, and...

  20. 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... comply with paragraphs (b)(1) and (b)(2) of this section. Pumps, valves, connectors, and agitators...

  1. 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... comply with paragraphs (b)(1) and (b)(2) of this section. Pumps, valves, connectors, and agitators...

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. 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...

  7. 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.

  8. 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...

  9. 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...

  10. 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...

  11. 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...

  12. 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...

  13. Fluid relief and check valve

    DOEpatents

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

    1986-07-17

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

  14. 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

  15. 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.

  16. 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.

  17. 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...

  18. 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...

  19. 49 CFR 230.49 - Setting of safety relief valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

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

  20. 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...

  1. 49 CFR 230.49 - Setting of safety relief valves.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

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

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

    Code of Federal Regulations, 2012 CFR

    2012-10-01

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

  3. 49 CFR 179.400-21 - Test of pressure relief valves.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

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

  4. 49 CFR 179.400-21 - Test of pressure relief valves.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

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

  5. 49 CFR 179.400-21 - Test of pressure relief valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

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

  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. Liquid rocket valve components

    NASA Technical Reports Server (NTRS)

    1973-01-01

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

  8. 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...

  9. 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...

  10. 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...

  11. 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...

  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. Refuge alternatives relief valve testing and design

    PubMed Central

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

    2016-01-01

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

  14. Refuge alternatives relief valve testing and design.

    PubMed

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

    2016-10-01

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

  15. Liquid rocket valve assemblies

    NASA Technical Reports Server (NTRS)

    1973-01-01

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

  16. 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

  17. 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...

  18. 46 CFR 154.1846 - Relief valves: Changing set pressure.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

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

  19. 46 CFR 154.1846 - Relief valves: Changing set pressure.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

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

  20. 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...

  1. 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...

  2. Liquid blocking check valve

    DOEpatents

    Merrill, John T.

    1984-01-01

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

  3. 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...

  4. 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...

  5. 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...

  6. 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...

  7. 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...

  8. 46 CFR 64.59 - Spring loaded pressure relief valve.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

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

  9. 46 CFR 64.59 - Spring loaded pressure relief valve.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

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

  10. 46 CFR 64.59 - Spring loaded pressure relief valve.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

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

  11. 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...

  12. 46 CFR 64.59 - Spring loaded pressure relief valve.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

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

  13. 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

  14. 46 CFR 54.15-10 - Safety and relief valves (modifies UG-126).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... relief valves shall be of the direct spring loaded type. (c) Safety and relief valves for steam or air... cast iron are prohibited. (g) The spring in a relief valve in service for pressures up to and including... percent below that for which the relief valve is marked. For higher pressures, the spring shall not...

  15. 46 CFR 54.15-10 - Safety and relief valves (modifies UG-126).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... relief valves shall be of the direct spring loaded type. (c) Safety and relief valves for steam or air... cast iron are prohibited. (g) The spring in a relief valve in service for pressures up to and including... percent below that for which the relief valve is marked. For higher pressures, the spring shall not...

  16. Liquid-blocking check valve

    DOEpatents

    Merrill, J.T.

    1982-09-27

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

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

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

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

  18. 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...

  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, 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...

  1. 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...

  2. 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...

  3. 46 CFR 154.519 - Piping relief valves.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

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

  4. 46 CFR 154.519 - Piping relief valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

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

  5. 46 CFR 154.519 - Piping relief valves.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

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

  6. 46 CFR 154.519 - Piping relief valves.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

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

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

    DTIC Science & Technology

    1980-10-01

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

  8. 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...

  9. 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...

  10. 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...

  11. 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...

  12. 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...

  13. 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 §...

  14. 46 CFR 54.15-10 - Safety and relief valves (modifies UG-126).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... of cast iron. Safety relief valves used in liquefied compressed gas service shall meet subpart 162... reference; see 46 CFR 54.01-1). (f) Cast iron may be employed in the construction of relief valves for... cast iron are prohibited. (g) The spring in a relief valve in service for pressures up to and...

  15. 46 CFR 54.15-10 - Safety and relief valves (modifies UG-126).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... of cast iron. Safety relief valves used in liquefied compressed gas service shall meet subpart 162... reference; see 46 CFR 54.01-1). (f) Cast iron may be employed in the construction of relief valves for... cast iron are prohibited. (g) The spring in a relief valve in service for pressures up to and...

  16. 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...

  17. 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...

  18. 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...

  19. 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...

  20. 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...

  1. 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....

  2. 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....

  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 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....

  6. 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....

  7. 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...

  8. 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....

  9. 46 CFR 38.25-10 - Safety relief valves-TB/ALL.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

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

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

    Code of Federal Regulations, 2013 CFR

    2013-10-01

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

  11. 49 CFR 179.200-23 - Tests of pressure relief valves.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 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...

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

    Code of Federal Regulations, 2011 CFR

    2011-10-01

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

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

    Code of Federal Regulations, 2012 CFR

    2012-10-01

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

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

    Code of Federal Regulations, 2014 CFR

    2014-10-01

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

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

    NASA Technical Reports Server (NTRS)

    2005-01-01

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

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

    Code of Federal Regulations, 2013 CFR

    2013-10-01

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

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

    Code of Federal Regulations, 2011 CFR

    2011-10-01

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

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

    Code of Federal Regulations, 2012 CFR

    2012-10-01

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

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

    Code of Federal Regulations, 2014 CFR

    2014-10-01

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

  20. 49 CFR 179.220-24 - Tests of pressure relief valves.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

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

  1. 49 CFR 179.220-24 - Tests of pressure relief valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

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

  2. 49 CFR 179.220-24 - Tests of pressure relief valves.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

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

  3. 46 CFR 56.50-25 - Safety and relief valve escape piping.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... supported and installed so that no stress is transmitted to the safety valve body. (c) Safety or relief... 46 Shipping 2 2010-10-01 2010-10-01 false Safety and relief valve escape piping. 56.50-25 Section... SYSTEMS AND APPURTENANCES Design Requirements Pertaining to Specific Systems § 56.50-25 Safety and...

  4. 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... Design and Equipment Cargo Venting Systems § 153.371 Minimum relief valve setting for refrigerated cargo tanks. The relief valve setting for a containment system that carries a refrigerated cargo must at...

  5. 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)....

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

    Code of Federal Regulations, 2012 CFR

    2012-10-01

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

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

    Code of Federal Regulations, 2011 CFR

    2011-10-01

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

  8. 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)....

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

    Code of Federal Regulations, 2014 CFR

    2014-10-01

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

  10. 77 FR 59408 - Finding of Equivalence; Alternate Pressure Relief Valve Settings on Certain Vessels Carrying...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-27

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

  11. 46 CFR 38.10-15 - Safety relief valves-TB/ALL.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

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

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

    Code of Federal Regulations, 2014 CFR

    2014-10-01

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

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

    Code of Federal Regulations, 2010 CFR

    2010-10-01

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

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

    Code of Federal Regulations, 2012 CFR

    2012-10-01

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

  16. 46 CFR 53.05-2 - Relief valve requirements for hot water boilers (modifies HG-400.2).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

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

  17. 46 CFR 53.05-2 - Relief valve requirements for hot water boilers (modifies HG-400.2).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

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

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

    SciTech Connect

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

    2002-07-01

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

  19. 49 CFR 179.200-23 - Tests of pressure relief valves.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

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

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

    Code of Federal Regulations, 2012 CFR

    2012-10-01

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

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

    Code of Federal Regulations, 2011 CFR

    2011-10-01

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

  2. 46 CFR 38.10-15 - Safety relief valves-TB/ALL.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

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

  3. 46 CFR 38.10-15 - Safety relief valves-TB/ALL.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

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

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

    SciTech Connect

    Gross, Robert; Harris, Stephen

    2007-08-01

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

  5. 46 CFR 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....

  6. 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.

  7. 46 CFR 154.517 - Piping: Liquid pressure relief.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

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

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

    Code of Federal Regulations, 2013 CFR

    2013-10-01

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

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

    Code of Federal Regulations, 2011 CFR

    2011-10-01

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

  10. 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.

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

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

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

  12. 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.

  13. 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...

  14. 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...

  15. 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...

  16. 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...

  17. 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...

  18. 33 CFR 149.105 - What are the requirements for the overflow and relief valves?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

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

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

    Code of Federal Regulations, 2010 CFR

    2010-10-01

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

  20. 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.

  1. The Liquid Metal Plasma Valve Closing Switch

    DTIC Science & Technology

    1976-11-01

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

  2. 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.

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

    NASA Technical Reports Server (NTRS)

    Urban, E. W.

    1980-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2012-06-01

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

  5. 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

  6. Binary Operation Of A Liquid-Crystal Light Valve

    NASA Technical Reports Server (NTRS)

    Davis, Jeffrey A.

    1990-01-01

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

  7. 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.

  8. 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.

  9. 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.

  10. Computational Modeling of Liquid and Gaseous Control Valves

    NASA Technical Reports Server (NTRS)

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

    2005-01-01

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

  11. Liquid-fuel valve with precise throttling control

    NASA Technical Reports Server (NTRS)

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

    1971-01-01

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

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

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

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

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

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

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

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

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

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

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

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

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

  16. 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.

  17. 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.

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

    DOE PAGES

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

    2015-12-01

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

  19. Smectic A and C* liquid crystal light valves

    NASA Astrophysics Data System (ADS)

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

    1993-07-01

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

  20. 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?

  1. 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.

  2. 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.

  3. Liquid-Crystal Light Valve Enhances Edges In Images

    NASA Technical Reports Server (NTRS)

    Chao, Tien-Hsin; Liu, Hua-Kuang

    1991-01-01

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

  4. Schottky diode silicon liquid-crystal light valve

    NASA Astrophysics Data System (ADS)

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

    1991-06-01

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

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

    Code of Federal Regulations, 2013 CFR

    2013-10-01

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

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

    Code of Federal Regulations, 2012 CFR

    2012-10-01

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

  7. 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.

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

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS... other pressure parts, except for pump seals and pressure relief devices, must be at least 4 times...

  9. Liquid crystal light valve technologies for display applications

    NASA Astrophysics Data System (ADS)

    Kikuchi, Hiroshi; Takizawa, Kuniharu

    2001-11-01

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

  10. 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...

  11. 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...

  12. 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...

  13. 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...

  14. 49 CFR 178.338-8 - Pressure relief devices, piping, valves, and fittings.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...) SPECIFICATIONS FOR PACKAGINGS Specifications for Containers for Motor Vehicle Transportation § 178.338-8 Pressure... pressure parts, except for pump seals and pressure relief devices, must be at least 4 times the...

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

    NASA Technical Reports Server (NTRS)

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

    1977-01-01

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

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

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., valves, hose, and fittings. (1) The burst pressure of all piping, pipe fittings, hose and other pressure... of the cargo tank. Additionally, the burst pressure may not be less than 4 times any higher pressure... must be tested for leakage at not less than 225 psig using dry air or inert gas. (c) Marking inlets...

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

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) Piping, valves, and fittings. (1) The burst pressure of all piping, pipe fittings, hoses and other... pressure of the tank. Additionally, the burst pressure may not be less than 4 times any higher pressure to..., and fittings have been tested after installation with gas or air and proved leak tight at not...

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

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...) Piping, valves, and fittings. (1) The burst pressure of all piping, pipe fittings, hoses and other... pressure of the tank. Additionally, the burst pressure may not be less than 4 times any higher pressure to..., and fittings have been tested after installation with gas or air and proved leak tight at not...

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

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...) Piping, valves, and fittings. (1) The burst pressure of all piping, pipe fittings, hoses and other... pressure of the tank. Additionally, the burst pressure may not be less than 4 times any higher pressure to..., and fittings have been tested after installation with gas or air and proved leak tight at not...

  20. 49 CFR 178.337-9 - Pressure relief devices, piping, valves, hoses, and fittings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

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

  1. 49 CFR 178.337-9 - Pressure relief devices, piping, valves, hoses, and fittings.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

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

  2. 49 CFR 178.337-9 - Pressure relief devices, piping, valves, hoses, and fittings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... in service. For chlorine service, see paragraph (b)(7) of this section. (2) Pipe joints must be... original pressure test. (8) Chlorine cargo tanks. Angle valves on cargo tanks intended for chlorine service must conform to the standards of the Chlorine Institute, Inc., Dwg. 104-8 or “Section 3, Pamphlet...

  3. 49 CFR 178.337-9 - Pressure relief devices, piping, valves, hoses, and fittings.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

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

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

    NASA Technical Reports Server (NTRS)

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

    1993-01-01

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

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

    PubMed

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

    2016-02-10

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

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

    NASA Technical Reports Server (NTRS)

    Urban, E. W.

    1981-01-01

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

  7. 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.

  8. 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.

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

    SciTech Connect

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

    2004-09-27

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

  10. VALVE

    DOEpatents

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

    1962-04-17

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

  11. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2007-01-01

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

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

    PubMed

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

    2010-01-21

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

  14. 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.

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

    PubMed

    Velescu, C; Popa, N C

    2015-01-01

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

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

    PubMed Central

    Velescu, C.; Popa, N. C.

    2015-01-01

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

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

    NASA Technical Reports Server (NTRS)

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

    2012-01-01

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

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

    NASA Technical Reports Server (NTRS)

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

    2008-01-01

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

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

    PubMed

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

    2010-06-22

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

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

    PubMed

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

    2015-02-25

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

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

    NASA Astrophysics Data System (ADS)

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

    2016-03-01

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

  2. 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.

  3. 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

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

    PubMed

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

    1997-12-15

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

  5. 40 CFR 265.1058 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) SOLID WASTES (CONTINUED) INTERIM STATUS STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT... § 265.1057(e). (e) Any connector that is inaccessible or is ceramic or ceramic-lined (e.g.,...

  6. 40 CFR 264.1058 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) SOLID WASTES (CONTINUED) STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND...) Any connector that is inaccessible or is ceramic or ceramic-lined (e.g., porcelain, glass, or...

  7. 40 CFR 265.1058 - Standards: Pumps and valves in heavy liquid service, pressure relief devices in light liquid or...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) SOLID WASTES (CONTINUED) INTERIM STATUS STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT... § 265.1057(e). (e) Any connector that is inaccessible or is ceramic or ceramic-lined (e.g.,...

  8. 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

    ...) SOLID WASTES (CONTINUED) STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND...) Any connector that is inaccessible or is ceramic or ceramic-lined (e.g., porcelain, glass, or...

  9. 46 CFR 154.802 - Alternate pressure relief settings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

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

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

    PubMed

    Narang, U

    2001-01-01

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

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

    NASA Astrophysics Data System (ADS)

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

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

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

    NASA Technical Reports Server (NTRS)

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

    1984-01-01

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

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

    NASA Technical Reports Server (NTRS)

    Chao, Tien-Hsin

    1989-01-01

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

  14. Microfluidic sieve valves

    DOEpatents

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

    2015-01-13

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

  15. Variable reluctance proximity sensors for cryogenic valve position indication

    NASA Technical Reports Server (NTRS)

    Cloyd, R. A.

    1982-01-01

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

  16. Temperature-Operated Valve

    NASA Technical Reports Server (NTRS)

    Morrison, Andrew D.

    1994-01-01

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

  17. Design of ITER Relief Lines

    NASA Astrophysics Data System (ADS)

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

    2017-02-01

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

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

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... than 0.25 percent leaking valves, the owner or operator may elect to monitor each valve once every 2... provided in paragraph (c)(3) of this section. VT = The sum of the total number of valves monitored....

  19. 40 CFR 65.106 - Standards: Valves in gas/vapor service and in light liquid service.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... than 0.25 percent leaking valves, the owner or operator may elect to monitor each valve once every 2... provided in paragraph (c)(3) of this section. VT = The sum of the total number of valves monitored....

  20. 40 CFR 65.106 - Standards: Valves in gas/vapor service and in light liquid service.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... than 0.25 percent leaking valves, the owner or operator may elect to monitor each valve once every 2... provided in paragraph (c)(3) of this section. VT = The sum of the total number of valves monitored....

  1. 40 CFR 65.106 - Standards: Valves in gas/vapor service and in light liquid service.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... than 0.25 percent leaking valves, the owner or operator may elect to monitor each valve once every 2... provided in paragraph (c)(3) of this section. VT = The sum of the total number of valves monitored....

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

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... than 0.25 percent leaking valves, the owner or operator may elect to monitor each valve once every 2... provided in paragraph (c)(3) of this section. VT = The sum of the total number of valves monitored....

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

    DTIC Science & Technology

    1984-02-01

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

  4. 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...

  5. 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...

  6. 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...

  7. 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...

  8. 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...

  9. 19 CFR 172.1 - Notice of liquidated damages or penalty incurred and right to petition for relief.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

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

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

    NASA Technical Reports Server (NTRS)

    Chao, Tien-Hsin; Yu, Jeffrey

    1990-01-01

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

  11. Main Oxidizer Valve Design

    NASA Technical Reports Server (NTRS)

    Addona, Brad; Eddleman, David

    2015-01-01

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

  12. 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...

  13. Safety valve

    DOEpatents

    Bergman, Ulf C.

    1984-01-01

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

  14. 40 CFR 63.1025 - Valves in gas and vapor service and in light liquid service standards.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... total valves in the applicable process unit or group of process units to be subdivided shall be less... the overall performance of total valves in the applicable process unit or group of process units is... overall performance of total valves in the applicable process unit or group of process units is 2...

  15. 40 CFR 63.1025 - Valves in gas and vapor service and in light liquid service standards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... total valves in the applicable process unit or group of process units to be subdivided shall be less... the overall performance of total valves in the applicable process unit or group of process units is... overall performance of total valves in the applicable process unit or group of process units is 2...

  16. 40 CFR 63.1025 - Valves in gas and vapor service and in light liquid service standards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... total valves in the applicable process unit or group of process units to be subdivided shall be less... the overall performance of total valves in the applicable process unit or group of process units is... overall performance of total valves in the applicable process unit or group of process units is 2...

  17. Solid handling valve

    DOEpatents

    Williams, William R.

    1979-01-01

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

  18. 77 FR 54839 - Clarification of Submission of Requests for Relief or Alternatives From the Regulatory...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-06

    ... Pressure Vessel Code (ASME BPV Code) and Code for Operation and Maintenance of Nuclear Power Plants (OM... evaluation. Provide the ASME BPV or OM Code examination or test requirements for the pump(s), valve(s), weld... specific pump(s), valve(s), weld(s), or component(s) for which the relief or alternative is requested....

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

    SciTech Connect

    Soyars, W. M.

    1999-01-01

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

  20. 49 CFR 179.500-16 - Tests of pressure relief devices.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

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

  1. 49 CFR 179.500-16 - Tests of pressure relief devices.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

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

  2. 49 CFR 179.500-16 - Tests of pressure relief devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

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

  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, 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...

  6. 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...

  7. 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...

  8. Drumlin relief

    NASA Astrophysics Data System (ADS)

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

    2012-06-01

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

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

    NASA Astrophysics Data System (ADS)

    Takizawa, Kuniharu

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

  10. 49 CFR 179.400-19 - Valves and gages.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

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

  11. 40 CFR 60.482-7a - Standards: Valves in gas/vapor service and in light liquid service.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Industry for Which Construction, Reconstruction, or Modification Commenced After November 7, 2006 § 60.482...)(5). If less than 2.0 percent of the valves are leaking for that process unit, the valve must be... bolts; (2) Replacement of bonnet bolts; (3) Tightening of packing gland nuts; (4) Injection of...

  12. 40 CFR 60.482-7 - Standards: Valves in gas/vapor service and in light liquid service.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Industry for which Construction, Reconstruction, or Modification Commenced After January 5, 1981, and on or....483-2(b)(5). If less than 2.0 percent of the valves are leaking for that process unit, the valve must... bolts; (2) Replacement of bonnet bolts; (3) Tightening of packing gland nuts; (4) Injection of...

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

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Industry for which Construction, Reconstruction, or Modification Commenced After January 5, 1981, and on or....483-2(b)(5). If less than 2.0 percent of the valves are leaking for that process unit, the valve must... bolts; (2) Replacement of bonnet bolts; (3) Tightening of packing gland nuts; (4) Injection of...

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

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Industry for Which Construction, Reconstruction, or Modification Commenced After November 7, 2006 § 60.482...)(5). If less than 2.0 percent of the valves are leaking for that process unit, the valve must be... bolts; (2) Replacement of bonnet bolts; (3) Tightening of packing gland nuts; (4) Injection of...

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

    PubMed

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

    2010-05-07

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

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

    PubMed

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

    2015-01-23

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

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

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... be made on the same basis and this shall be the basis used for comparison with the subgrouping... has been delayed by the total number of valves subject to the requirements of this section. (d)...

  18. 40 CFR 63.1006 - Valves in gas and vapor service and in light liquid service standards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... be made on the same basis and this shall be the basis used for comparison with the subgrouping... has been delayed by the total number of valves subject to the requirements of this section. (d)...

  19. Heart valve surgery - discharge

    MedlinePlus

    ... surgery - minimally invasive Aortic valve surgery - open Bicuspid aortic valve Endocarditis Heart valve surgery Mitral valve prolapse Mitral valve surgery - minimally invasive Mitral valve surgery - open Pulmonary valve stenosis Smoking - tips on how to quit Patient Instructions ...

  20. 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...

  1. 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...

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. 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...

  7. Check valve

    DOEpatents

    Upton, H.A.; Garcia, P.

    1999-08-24

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

  8. Check valve

    DOEpatents

    Upton, Hubert Allen; Garcia, Pablo

    1999-08-24

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

  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. 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...

  12. 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...

  13. Valve Disease

    MedlinePlus

    ... valves in the heart: tricuspid, pulmonary, mitral, and aortic. Two types of problems can disrupt blood flow though the valves: regurgitation or stenosis. Regurgitation is also called insufficiency or incompetence. Regurgitation ...

  14. Design criteria monograph for valve components

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Monograph treats valve design technology problems as they were solved in successful development of flightweight operational valves for liquid rocket systems. General practices for cleaning and contamination prevention are summarized. Balance of information is arranged by topic, since detail design requirements apply to most types of valves.

  15. Fast valve

    DOEpatents

    Van Dyke, W.J.

    1992-04-07

    A fast valve is disclosed that can close on the order of 7 milliseconds. It is closed by the force of a compressed air spring with the moving parts of the valve designed to be of very light weight and the valve gate being of wedge shaped with O-ring sealed faces to provide sealing contact without metal to metal contact. The combination of the O-ring seal and an air cushion create a soft final movement of the valve closure to prevent the fast air acting valve from having a harsh closing. 4 figs.

  16. Fast valve

    DOEpatents

    Van Dyke, William J.

    1992-01-01

    A fast valve is disclosed that can close on the order of 7 milliseconds. It is closed by the force of a compressed air spring with the moving parts of the valve designed to be of very light weight and the valve gate being of wedge shaped with O-ring sealed faces to provide sealing contact without metal to metal contact. The combination of the O-ring seal and an air cushion create a soft final movement of the valve closure to prevent the fast air acting valve from having a harsh closing.

  17. Analysis of Complex Valve and Feed Systems

    NASA Technical Reports Server (NTRS)

    Ahuja, Vineet; Hosangadi, Ashvin; Shipman, Jeremy; Cavallo, Peter; Dash, Sanford

    2007-01-01

    A numerical framework for analysis of complex valve systems supports testing of propulsive systems by simulating key valve and control system components in the test loop. In particular, it is designed to enhance the analysis capability in terms of identifying system transients and quantifying the valve response to these transients. This system has analysis capability for simulating valve motion in complex systems operating in diverse flow regimes ranging from compressible gases to cryogenic liquids. A key feature is the hybrid, unstructured framework with sub-models for grid movement and phase change including cryogenic cavitations. The multi-element unstructured framework offers improved predictions of valve performance characteristics under steady conditions for structurally complex valves such as pressure regulator valve. Unsteady simulations of valve motion using this computational approach have been carried out for various valves in operation at Stennis Space Center such as the split-body valve and the 10-in. (approx.25.4-cm) LOX (liquid oxygen) valve and the 4-in. (approx.10 cm) Y-pattern valve (liquid nitrogen). Such simulations make use of variable grid topologies, thereby permitting solution accuracy and resolving important flow physics in the seat region of the moving valve. An advantage to this software includes possible reduction in testing costs incurred due to disruptions relating to unexpected flow transients or functioning of valve/flow control systems. Prediction of the flow anomalies leading to system vibrations, flow resonance, and valve stall can help in valve scheduling and significantly reduce the need for activation tests. This framework has been evaluated for its ability to predict performance metrics like flow coefficient for cavitating venturis and valve coefficient curves, and could be a valuable tool in predicting and understanding anomalous behavior of system components at rocket propulsion testing and design sites.

  18. Depressurization valve

    DOEpatents

    Skoda, G.I.

    1989-03-28

    A depressurization valve for use in relieving completely the pressure in a simplified boiling water reactor is disclosed. The normally closed and sealed valve is provided with a valve body defining a conduit from an outlet of a manifold from the reactor through a valve seat. A closing valve disk is configured for fitting to the valve seat to normally close the valve. The seat below the disk is provided with a radially extending annulus extending a short distance into the aperture defined by the seat. The disk is correspondingly provided with a longitudinally extending annulus that extends downwardly through the aperture defined by the seat towards the high pressure side of the valve body. A ring shaped membrane is endlessly welded to the seat annulus and to the disk annulus. The membrane is conformed over the confronted surface of the seat and disk in a C-sectioned configuration to seal the depressurization valve against the possibility of weeping. The disk is held to the closed position by an elongate stem extending away from the high pressure side of the valve body. The stem has a flange configured integrally to the stem for bias by two springs. The first spring acts from a portion of the housing overlying the disk on the stem flange adjacent the disk. This spring urges the stem and attached disk away from the seat and thus will cause the valve to open at any pressure. A second spring-preferably of the Belleville variety-acts on a latch plate surrounding and freely moving relative to the end of the stem. This second spring overcomes the bias of the first spring and any pressure acting upon the disk. This Belleville spring maintains through its spring force the valve in the closed position. At the same time, the latch plate with its freedom of movement relative to the stem allows the stem to thermally expand during valve temperature excursion.

  19. Computations Of Flows In Flapper Valves

    NASA Technical Reports Server (NTRS)

    Kandula, Mastanaiah; Pearce, Dan

    1993-01-01

    Three reports describe computational studies of flows of liquid oxygen and liquid hydrogen in flapper valves located at quick-disconnect interface between main propellant feedlines of Space Shuttle orbiter and Space Shuttle external tank.

  20. EVALUATION OF A MULTIFUNCTIONAL VALVE ASSEMBLY IN A DIRECT EXPANSION REFRIGERATION SYSTEM REPORT

    EPA Science Inventory

    The report describes the performance, including energy consumption, of a refrigeration system incorporating a multifunctional valve (MXV assembly). The MXV assembly (consisting of additional liquid line, an XTC valve, and a larger thermostatic expansion valve) was installed on al...

  1. Problem: Heart Valve Stenosis

    MedlinePlus

    ... valve . Learn about the different types of stenosis: Aortic stenosis Tricuspid stenosis Pulmonary stenosis Mitral stenosis Outlook for ... Disease "Innocent" Heart Murmur Problem: Valve Stenosis - Problem: Aortic Valve Stenosis - Problem: Mitral Valve Stenosis - Problem: Tricuspid Valve Stenosis - ...

  2. Depressurization valve

    DOEpatents

    Skoda, George I.

    1989-01-01

    A depressurization valve for use in relieving completely the pressure in a simplified boiling water reactor is disclosed. The normally closed and sealed valve is provided with a valve body defining a conduit from an outlet of a manifold from the reactor through a valve seat. A closing valve disk is configured for fitting to the valve seat to normally close the valve. The seat below the disk is provided with a radially extending annulus extending a short distance into the aperture defined by the seat. The disk is correspondingly provided with a longitudinally extending annulus that extends downwardly through the aperture defined by the seat towards the high pressure side of the valve body. A ring shaped membrane is endlessly welded to the seat annulus and to the disk annulus. The membrane is conformed over the confronted surface of the seat and disk in a C-sectioned configuration to seal the depressurization valve against the possibility of weeping. The disk is held to the closed position by an elongate stem extending away from the high pressure side of the valve body. The stem has a flange configured integrally to the stem for bias by two springs. The first spring acts from a portion of the housing overlying the disk on the stem flange adjacent the disk. This spring urges the stem and attached disk away from the seat and thus will cause the valve to open at any pressure. A second spring--preferably of the Belleville variety--acts on a latch plate surrounding and freely moving relative to the end of the stem. This second spring overcomes the bias of the first spring and any pressure acting upon the disk. This Belleville spring maintains through its spring force the valve in the closed position. At the same time, the latch plate with its freedom of movement relative to the stem allows the stem to thermally expand during valve temperature excursion. The latch plate in surrounding the stem is limited in its outward movement by a boss attached to the stem at the end of

  3. Bipropellant shut-off valve

    NASA Technical Reports Server (NTRS)

    Smith, J. V.

    1971-01-01

    An advanced design of an all metal, fast response, bipropellant, shut-off valve for use on long duration space missions is reported. The valve provides the flow control capability for a 1,000 lb thrust, bipropellant engine using oxygen difluoride and diborane as propellants. The shutoff seal selection is a soft-on-hard metal concept. The soft seal is a spherical shell that seats against a hard conical seat. Beryllium copper and beryllium nickel seals were selected to seal against an electrolyzed Inconel 718 seat. Poppet shaft sealing is achieved by use of hydroformed, Inconel 718 bellows. Two valve assemblies were fabricated and subjected to a series of tests including leak, response time, flow capacity, dry cycles, water cycles, liquid nitrogen cycles, liquid fluorine cycles, and lead-lag operation cycles. These tests demonstrated the ability of the valve to meet design goals.

  4. Septoplasty for left ventricular outflow obstruction without aortic valve replacement: a new technique.

    PubMed

    Cooley, D A; Garrett, J R

    1986-10-01

    A new technique is described for relief of diffuse obstruction in the left ventricular outflow tract without aortic valve replacement. Left ventricular septoplasty was performed, preserving the aortic valve. The supra-valve stenosis was repaired using a Y-shaped extension of the aortotomy proximally and a pantaloon-shaped patch of woven Dacron fabric. A 10-year-old girl with "tunnel" or diffuse stenosis obtained striking relief of left ventricular hypertension by this technique.

  5. Additively Manufactured Main Fuel Valve Housing

    NASA Technical Reports Server (NTRS)

    Eddleman, David; Richard, Jim

    2015-01-01

    Selective Laser Melting (SLM) was utilized to fabricate a liquid hydrogen valve housing typical of those found in rocket engines and main propulsion systems. The SLM process allowed for a valve geometry that would be difficult, if not impossible to fabricate by traditional means. Several valve bodies were built by different SLM suppliers and assembled with valve internals. The assemblies were then tested with liquid nitrogen and operated as desired. One unit was also burst tested and sectioned for materials analysis. The design, test results, and planned testing are presented herein.

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. Nuclear radiation actuated valve

    DOEpatents

    Christiansen, David W.; Schively, Dixon P.

    1985-01-01

    A nuclear radiation actuated valve for a nuclear reactor. The valve has a valve first part (such as a valve rod with piston) and a valve second part (such as a valve tube surrounding the valve rod, with the valve tube having side slots surrounding the piston). Both valve parts have known nuclear radiation swelling characteristics. The valve's first part is positioned to receive nuclear radiation from the nuclear reactor's fuel region. The valve's second part is positioned so that its nuclear radiation induced swelling is different from that of the valve's first part. The valve's second part also is positioned so that the valve's first and second parts create a valve orifice which changes in size due to the different nuclear radiation caused swelling of the valve's first part compared to the valve's second part. The valve may be used in a nuclear reactor's core coolant system.

  12. 49 CFR 179.500-16 - Tests of pressure relief devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... tested by air or gas before being put into service. Valve shall open at pressure not exceeding the marked... relief devices that incorporate a rupture disc, samples of the discs used shall burst at a pressure...

  13. A throat-bypass stability-bleed system using relief valves to increase the transient stability of a mixed-compression inlet. [YF-12 aircraft inlet tests in the Lewis 10 by 10 ft supersonic wind tunnel

    NASA Technical Reports Server (NTRS)

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

    1979-01-01

    A stability-bleed system was installed in a YF-12 flight inlet that was subjected to internal and external airflow disturbances in the NASA Lewis 10 by 10 foot supersonic wind tunnel. The purpose of the system is to allow higher inlet performance while maintaining a substantial tolerance (without unstart) to internal and external disturbances. At Mach numbers of 2.47 and 2.76, the inlet tolerance to decreases in diffuser-exit corrected airflow was increased by approximately 10 percent of the operating-point airflow. The stability-bleed system complemented the terminal-shock-control system of the inlet and did not show interaction problems. For disturbances which caused a combined decrease in Mach number and increase in angle of attack, the system with valves operative kept the inlet started 4 to 28 times longer than with the valves inoperative. Hence, the stability system provides additional time for the inlet control system to react and prevent unstart. This was observed for initial Mach numbers of 2.55 and 2.68. For slow increase in angle of attack at Mach 2.47 and 2.76, the system kept the inlet started beyond the steady-state unstart angle. However, the maximum transient angles of attack without unstart could not be determined because wind-tunnel mechanical-stop limits for angle of attack were reached.

  14. Self-Rupturing Hermetic Valve

    NASA Technical Reports Server (NTRS)

    Tucker, Curtis E., Jr.; Sherrit, Stewart

    2011-01-01

    For commercial, military, and aerospace applications, low-cost, small, reliable, and lightweight gas and liquid hermetically sealed valves with post initiation on/off capability are highly desirable for pressurized systems. Applications include remote fire suppression, single-use system-pressurization systems, spacecraft propellant systems, and in situ instruments. Current pyrotechnic- activated rupture disk hermetic valves were designed for physically larger systems and are heavy and integrate poorly with portable equipment, aircraft, and small spacecraft and instrument systems. Additionally, current pyrotechnically activated systems impart high g-force shock loads to surrounding components and structures, which increase the risk of damage and can require additional mitigation. The disclosed mechanism addresses the need for producing a hermetically sealed micro-isolation valve for low and high pressure for commercial, aerospace, and spacecraft applications. High-precision electrical discharge machining (EDM) parts allow for the machining of mated parts with gaps less than a thousandth of an inch. These high-precision parts are used to support against pressure and extrusion, a thin hermetically welded diaphragm. This diaphragm ruptures from a pressure differential when the support is removed and/or when the plunger is forced against the diaphragm. With the addition of conventional seals to the plunger and a two-way actuator, a derivative of this design would allow nonhermetic use as an on/off or metering valve after the initial rupturing of the hermetic sealing disk. In addition, in a single-use hermetically sealed isolation valve, the valve can be activated without the use of potential leak-inducing valve body penetrations. One implementation of this technology is a high-pressure, high-flow-rate rupture valve that is self-rupturing, which is advantageous for high-pressure applications such as gas isolation valves. Once initiated, this technology is self

  15. Simple Check Valves for Microfluidic Devices

    NASA Technical Reports Server (NTRS)

    Willis, Peter A.; Greer, Harold F.; Smith, J. Anthony

    2010-01-01

    A simple design concept for check valves has been adopted for microfluidic devices that consist mostly of (1) deformable fluorocarbon polymer membranes sandwiched between (2) borosilicate float glass wafers into which channels, valve seats, and holes have been etched. The first microfluidic devices in which these check valves are intended to be used are micro-capillary electrophoresis (microCE) devices undergoing development for use on Mars in detecting compounds indicative of life. In this application, it will be necessary to store some liquid samples in reservoirs in the devices for subsequent laboratory analysis, and check valves are needed to prevent cross-contamination of the samples. The simple check-valve design concept is also applicable to other microfluidic devices and to fluidic devices in general. These check valves are simplified microscopic versions of conventional rubber- flap check valves that are parts of numerous industrial and consumer products. These check valves are fabricated, not as separate components, but as integral parts of microfluidic devices. A check valve according to this concept consists of suitably shaped portions of a deformable membrane and the two glass wafers between which the membrane is sandwiched (see figure). The valve flap is formed by making an approximately semicircular cut in the membrane. The flap is centered over a hole in the lower glass wafer, through which hole the liquid in question is intended to flow upward into a wider hole, channel, or reservoir in the upper glass wafer. The radius of the cut exceeds the radius of the hole by an amount large enough to prevent settling of the flap into the hole. As in a conventional rubber-flap check valve, back pressure in the liquid pushes the flap against the valve seat (in this case, the valve seat is the adjacent surface of the lower glass wafer), thereby forming a seal that prevents backflow.

  16. Bistable (latching) solenoid actuated propellant isolation valve

    NASA Technical Reports Server (NTRS)

    Wichmann, H.; Deboi, H. H.

    1979-01-01

    The design, fabrication, assembly and test of a development configuration bistable (latching) solenoid actuated propellant isolation valve suitable for the control hydrazine and liquid fluorine to an 800 pound thrust rocket engine is described. The valve features a balanced poppet, utilizing metal bellows, a hard poppet/seat interface and a flexure support system for the internal moving components. This support system eliminates sliding surfaces, thereby rendering the valve free of self generated particles.

  17. Smart actuators: Valve Health Monitor (VHM) system

    NASA Astrophysics Data System (ADS)

    Perotti, José; Lucena, Angel; Burns, Bradley

    2006-05-01

    The health of electromechanical systems (actuators) and specifically of solenoid valves is a primary concern at Kennedy Space Center (KSC). These systems control the storage and transfer of such commodities as liquid hydrogen. The potential for the failure of electromechanical systems to delay a scheduled launch or to cause personnel injury requires continual maintenance and testing of the systems to ensure their readiness. Monitoring devices need to be incorporated into these systems to verify the health and performance of the valves during real operating conditions. It is very advantageous to detect degradation and/or potential problems before they happen. This feature will not only provide safer operation but save the cost of unnecessary maintenance and inspections. Solenoid valve status indicators are often based upon microswitches that work by physically contacting a valve's poppet assembly. All of the physical contact and movement tends to be very unreliable and is subject to wear and tear of the assemblies, friction, breakage of the switch, and even leakage of the fluid (gas or liquid) in the valve. The NASA Instrumentation Branch, together with its contractor, ASRC Aerospace, has developed a solenoid valve smart current signature sensor that monitors valves in a noninvasive mode. The smart system monitors specific electrical parameters of the solenoid valves and detects and predicts the performance and health of the device. The information obtained from the electrical signatures of these valves points to not only electrical components failures in the valves but also mechanical failures and/or degradations.

  18. Aortic Valve Regurgitation

    MedlinePlus

    ... valve. Also, a narrowing of the aortic valve (aortic stenosis) can be associated with leaking. High blood pressure (hypertension). High blood pressure may stretch the root of the aorta where the aortic valve sits. The valve flaps ( ...

  19. Mitral Valve Disease

    MedlinePlus

    ... Heart Disease Diseases of the arteries, valves, and aorta, as well as cardiac rhythm disturbances Aortic Valve ... are two main types of mitral valve disease: Stenosis – the valve does not open enough to allow ...

  20. TWO-WAY FREEZE VALVE

    DOEpatents

    Lantz, K.D.; Clark, P.M.

    1960-01-01

    A valve for closing off the flow of radioactive and corrosive gases and liquids or mixtures thereof and forming a leak tight barrier is described. This valve has no mechanical moving parts which would require design to close tolerances and retention of the usual seal tighthess. Instead, there is provided a cavity in which a fusible metal is contained. Heating and cooling are provided to exercise control over the state of the metal. Baffle chambers are utilized to separate the molten fusible metal from the gas or liquid which is being passed through and return the molten metal to its cavity.

  1. 49 CFR 179.300-17 - Tests of pressure relief devices.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... CARS Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A and 110AW) § 179.300-17 Tests of pressure relief devices. (a) Each valve shall be tested by air or gas before being put into service. The... Cars (IBR, see § 171.7 of this subchapter). (c) For pressure relief devices of the fusible plug type,...

  2. 49 CFR 179.300-17 - Tests of pressure relief devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... FOR TANK CARS Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A and 110AW) § 179.300-17 Tests of pressure relief devices. (a) Each valve shall be tested by air or gas before being put into... Specifications for Tank Cars (IBR, see § 171.7 of this subchapter). (c) For pressure relief devices of...

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

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... CARS Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A and 110AW) § 179.300-17 Tests of pressure relief devices. (a) Each valve shall be tested by air or gas before being put into service. The... Cars (IBR, see § 171.7 of this subchapter). (c) For pressure relief devices of the fusible plug type,...

  4. 49 CFR 179.300-17 - Tests of pressure relief devices.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... CARS Specifications for Multi-Unit Tank Car Tanks (Classes DOT-106A and 110AW) § 179.300-17 Tests of pressure relief devices. (a) Each valve shall be tested by air or gas before being put into service. The... Cars (IBR, see § 171.7 of this subchapter). (c) For pressure relief devices of the fusible plug type,...

  5. A calcified polymeric valve for valve-in-valve applications.

    PubMed

    Falahatpisheh, Ahmad; Morisawa, Daisuke; Toosky, Taraz T; Kheradvar, Arash

    2017-01-04

    The prevalence of aortic valve stenosis (AS) is increasing in the aging society. More recently, novel treatments and devices for AS, especially transcatheter aortic valve replacement (TAVR) have significantly changed the therapeutic approach to this disease. Research and development related to TAVR require testing these devices in the calcified heart valves that closely mimic a native calcific valve. However, no animal model of AS has yet been available. Alternatively, animals with normal aortic valve that are currently used for TAVR experiments do not closely replicate the aortic valve pathology required for proper testing of these devices. To solve this limitation, for the first time, we developed a novel polymeric valve whose leaflets possess calcium hydroxyapatite inclusions immersed in them. This study reports the characteristics and feasibility of these valves. Two types of the polymeric valve, i.e., moderate and severe calcified AS models were developed and tested by deploying a transcatheter valve in those and measuring the related hemodynamics. The valves were tested in a heart flow simulator, and were studied using echocardiography. Our results showed high echogenicity of the polymeric valve, that was correlated to the severity of the calcification. Aortic valve area of the polymeric valves was measured, and the severity of stenosis was defined according to the clinical guidelines. Accordingly, we showed that these novel polymeric valves closely mimic AS, and can be a desired cost-saving solution for testing the performance of the transcatheter aortic valve systems in vitro.

  6. Wear resistant valve

    NASA Technical Reports Server (NTRS)

    Perkins, Gerald S. (Inventor)

    1980-01-01

    A valve which is resistant to wear caused by particles trapped between the valve seat and the valve member or poppet when the valve closes, including an outlet for directing washing fluid at the valve seat and/or sealing face of the poppet and means for supplying pressured fluid to the outlet at the time when the valve is closing.

  7. 49 CFR 236.383 - Valve locks, valves, and valve magnets.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Valve locks, valves, and valve magnets. 236.383... Inspection and Tests § 236.383 Valve locks, valves, and valve magnets. Valve locks on valves of the non-cut-off type shall be tested at least once every three months, and valves and valve magnets shall...

  8. 49 CFR 236.383 - Valve locks, valves, and valve magnets.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Valve locks, valves, and valve magnets. 236.383... Inspection and Tests § 236.383 Valve locks, valves, and valve magnets. Valve locks on valves of the non-cut-off type shall be tested at least once every three months, and valves and valve magnets shall...

  9. 49 CFR 236.383 - Valve locks, valves, and valve magnets.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Valve locks, valves, and valve magnets. 236.383... Inspection and Tests § 236.383 Valve locks, valves, and valve magnets. Valve locks on valves of the non-cut-off type shall be tested at least once every three months, and valves and valve magnets shall...

  10. 49 CFR 236.383 - Valve locks, valves, and valve magnets.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Valve locks, valves, and valve magnets. 236.383... Inspection and Tests § 236.383 Valve locks, valves, and valve magnets. Valve locks on valves of the non-cut-off type shall be tested at least once every three months, and valves and valve magnets shall...

  11. 49 CFR 236.383 - Valve locks, valves, and valve magnets.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Valve locks, valves, and valve magnets. 236.383... Inspection and Tests § 236.383 Valve locks, valves, and valve magnets. Valve locks on valves of the non-cut-off type shall be tested at least once every three months, and valves and valve magnets shall...

  12. Piezoelectric valve

    SciTech Connect

    Petrenko, Serhiy Fedorovich

    2013-01-15

    A motorized valve has a housing having an inlet and an outlet to be connected to a pipeline, a saddle connected with the housing, a turn plug having a rod, the turn plug cooperating with the saddle, and a drive for turning the valve body and formed as a piezoelectric drive, the piezoelectric drive including a piezoelectric generator of radially directed standing acoustic waves, which is connected with the housing and is connectable with a pulse current source, and a rotor operatively connected with the piezoelectric generator and kinematically connected with the rod of the turn plug so as to turn the turn plug when the rotor is actuated by the piezoelectric generator.

  13. 46 CFR 154.546 - Excess flow valve: Closing flow.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Excess flow valve: Closing flow. 154.546 Section 154.546... and Process Piping Systems § 154.546 Excess flow valve: Closing flow. (a) The rated closing flow of vapor or liquid cargo for an excess flow valve must be specially approved by the Commandant (CG-522)....

  14. Reduced Order Modeling of SLS Liquid Hydrogen Pre-Valve Flow Guide to Enable Rapid Transient Analysis

    NASA Technical Reports Server (NTRS)

    Brown, Andrew M.; Mulder, Andrew

    2017-01-01

    NASA is developing a new launch vehicle, called the Space Launch System (SLS), which is intended on taking humans out of low earth orbit to destinations including the moon, asteroids, and Mars. The propulsion system for the core stage of this vehicle includes four RS-25 Liquid Hydrogen/Oxygen rocket engines. These engines are upgraded versions of the Space Shuttle Main Engines (SSME); the upgrades include higher power levels and affordability enhancements. As with any new vehicle, the Main Propulsion System (MPS), which include the feedlines and ancillary hardware connecting the engines to the fuel and oxidizer tanks, had to be redesigned (figure 1 - export clearance in progress), as the previous MPS for the SSME's was inherently part of the Space Shuttle System, which had a completely different overall configuration.

  15. Electrodynamic actuators for rocket engine valves

    NASA Technical Reports Server (NTRS)

    Fiet, O.; Doshi, D.

    1972-01-01

    Actuators, employed in acoustic loudspeakers, operate liquid rocket engine valves by replacing light paper cones with flexible metal diaphragms. Comparative analysis indicates better response time than solenoid actuators, and improved service life and reliability.

  16. Excess flow shutoff valve

    DOEpatents

    Kiffer, Micah S.; Tentarelli, Stephen Clyde

    2016-02-09

    Excess flow shutoff valve comprising a valve body, a valve plug, a partition, and an activation component where the valve plug, the partition, and activation component are disposed within the valve body. A suitable flow restriction is provided to create a pressure difference between the upstream end of the valve plug and the downstream end of the valve plug when fluid flows through the valve body. The pressure difference exceeds a target pressure difference needed to activate the activation component when fluid flow through the valve body is higher than a desired rate, and thereby closes the valve.

  17. Propellant isolation shutoff valve program

    NASA Technical Reports Server (NTRS)

    Merritt, F. L.

    1973-01-01

    An analysis and design effort directed to advancing the state-of-the-art of space storable isolation valves for control of flow of the propellants liquid fluorine/hydrazine and Flox/monomethylhydrazine is discussed. Emphasis is on achieving zero liquid leakage and capability of withstanding missions up to 10 years in interplanetary space. Included is a study of all-metal poppet sealing theory, an evaluation of candidate seal configurations, a valve actuator trade-off study and design description of a pneumo-thermally actuated soft metal poppet seal valve. The concepts and analysis leading to the soft seal approach are documented. A theoretical evaluation of seal leakage versus seal loading, related finishes and yield strengths of various materials is provided. Application of a confined soft aluminum seal loaded to 2 to 3 times yield strength is recommended. Use of either an electro-mechanical or pneumatic actuator appears to be feasible for the application.

  18. 46 CFR 53.05-1 - Safety valve requirements for steam boilers (modifies HG-400 and HG-401).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Safety valve requirements for steam boilers (modifies HG... (CONTINUED) MARINE ENGINEERING HEATING BOILERS Pressure Relieving Devices (Article 4) § 53.05-1 Safety valve requirements for steam boilers (modifies HG-400 and HG-401). (a) The pressure relief valve requirements and...

  19. 46 CFR 53.05-1 - Safety valve requirements for steam boilers (modifies HG-400 and HG-401).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Safety valve requirements for steam boilers (modifies HG... (CONTINUED) MARINE ENGINEERING HEATING BOILERS Pressure Relieving Devices (Article 4) § 53.05-1 Safety valve requirements for steam boilers (modifies HG-400 and HG-401). (a) The pressure relief valve requirements and...

  20. 46 CFR 53.05-1 - Safety valve requirements for steam boilers (modifies HG-400 and HG-401).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Safety valve requirements for steam boilers (modifies HG... (CONTINUED) MARINE ENGINEERING HEATING BOILERS Pressure Relieving Devices (Article 4) § 53.05-1 Safety valve requirements for steam boilers (modifies HG-400 and HG-401). (a) The pressure relief valve requirements and...

  1. 46 CFR 53.05-1 - Safety valve requirements for steam boilers (modifies HG-400 and HG-401).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Safety valve requirements for steam boilers (modifies HG... (CONTINUED) MARINE ENGINEERING HEATING BOILERS Pressure Relieving Devices (Article 4) § 53.05-1 Safety valve requirements for steam boilers (modifies HG-400 and HG-401). (a) The pressure relief valve requirements and...

  2. 46 CFR 53.05-1 - Safety valve requirements for steam boilers (modifies HG-400 and HG-401).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Safety valve requirements for steam boilers (modifies HG... (CONTINUED) MARINE ENGINEERING HEATING BOILERS Pressure Relieving Devices (Article 4) § 53.05-1 Safety valve requirements for steam boilers (modifies HG-400 and HG-401). (a) The pressure relief valve requirements and...

  3. Determination of salivary cotinine through solid phase extraction using a bead-injection lab-on-valve approach hyphenated to hydrophilic interaction liquid chromatography.

    PubMed

    Ramdzan, Adlin N; Barreiros, Luísa; Almeida, M Inês G S; Kolev, Spas D; Segundo, Marcela A

    2016-01-15

    Cotinine, the first metabolite of nicotine, is often used as a biomarker in the monitoring of environmental tobacco smoke (ETS) exposure due to its long half-life. This paper reports on the development of an at-line automatic micro-solid phase extraction (μSPE) method for the determination of salivary cotinine followed by its analysis via hydrophilic interaction liquid chromatography (HILIC). The SPE methodology is based on the bead injection (BI) concept in a mesofluidic lab-on-valve (LOV) flow system to automatically perform all SPE steps. Three commercially available reversed-phase sorbents were tested, namely, Oasis HLB, Lichrolut EN and Focus, and the spherically shaped sorbents (i.e., Oasis HLB and Focus) provided better packing within the SPE column and hence higher column efficiency. An HILIC column was chosen based on its potential for achieving higher sensitivity and better retention of polar compounds such as cotinine. The method uses an isocratic program with acetonitrile:100mM ammonium acetate buffer, pH 5.8 in 95:5 v/v ratio as the mobile phase at a flow rate of 1.0 mL min(-1). Using this approach, the linear calibration range was from 10 to 1000 ng which corresponded to 5-500 μg L(-1). The corresponding μSPE-BI-LOV system was proven to be reliable in the handing and analysis of viscous biological samples such as saliva, achieving a sampling rate of 6h(-1) and a limit of detection and quantification of 1.5 and 3μgL(-1), respectively.

  4. Valve-less microdispenser

    NASA Astrophysics Data System (ADS)

    Tan, Ming Kwang; Xin, Wang; Lee, Weng Kent

    2015-11-01

    We demonstrate the concept of valve-less microdispenser to control of the liquid flow through the nozzle, by incorporating Leidenfrost effect into the nozzle design. When the nozzle is heated above the Leidenfrost point, a thin vapor layer is formed between the heated substrate and the liquid above it. The vapor pressure due to the presence of the vapor layer, together with the effect of surface tension of the liquid, exerted on the liquid-vapor interface, preventing the flow of the liquid through the nozzle. The experimental results shown that nozzles of diameter 400 micrometer and below, the nozzle temperature of 150 degree Celsius is sufficient to prevent the continuous flowing of the liquid, whereas for nozzles of diameter between 400 to 500 micrometer, the nozzle temperature needs to increase to 160 degree Celsius in order to prevent the continuous flowing of the liquid. When nozzle temperature below 160 degree Celsius, intermittent ejection of microdroplets, whose size is a function of nozzle temperature, is observed.

  5. ELECTROSTRICTION VALVE

    DOEpatents

    Kippenhan, D.O.

    1962-09-25

    An accurately controlled, pulse gas valve is designed capable of delivering output pulses which vary in length from one-tenth millisecond to one second or more, repeated at intervals of a few milliseconds or- more. The pulsed gas valve comprises a column formed of barium titanate discs mounted in stacked relation and electrically connected in parallel, with means for applying voltage across the discs to cause them to expand and effect a mechanical elongation axially of the column. The column is mounted within an enclosure having an inlet port and an outlet port with an internal seat in communication with the outlet port, such that a plug secured to the end of the column will engage the seat of the outlet port to close the outlet port in response to the application of voltage is regulated by a conventional electronic timing circuit connected to the column. (AEC)

  6. Dump valve

    SciTech Connect

    Webber, J.C.

    1981-06-23

    A swab assembly is provided having a dump valve responsive to fluid pressure and drag which will dump the fluid load should either fluid load or drag or the effect of both fluid load and drag become abnormal. Also if the fluid pressure and/or drag become abnormal, the fluid load on the cup will be released and wash away foreign material causing abnormal drag. When the cup is dumped the pulling capabilities of the wireline truck can concentrate on overcoming the drag. The dump valve opens to wide open position and remains open to dump the fluid to assist in washing away solid materials above the cup. A swab assembly also is provided which with normal drag and an overload, may be pulled relatively slowly, but if pulled too rapidly will result in the load on the swab being dumped to protect the swab assembly and the pulling apparatus from damage. 15 claims.

  7. Semitoroidal-diaphragm cavitating valve designed for bipropellant flow control

    NASA Technical Reports Server (NTRS)

    Young, A. L.

    1969-01-01

    Valve controls the flow of bipropellant liquids in rocket engines. Throttling and cavitation of the liquids are controlled by axial deflections of a semitoroidal metal diaphram. The valve is highly resistant to corrosion and leakage, and should be useful in food processing and chemical industries.

  8. Mitral Valve Prolapse

    MedlinePlus

    ... Personal Stories Support Network: You're Not Alone Heart Valve Disease Symptoms Dr. Robert Bonow describes the symptoms that may alert you to heart valve disease. Valve Disease Resources Patient Guide: Understanding Your Heart ...

  9. Automatic shutoff valve

    NASA Technical Reports Server (NTRS)

    Hawkins, S. F.; Overbey, C. W.

    1980-01-01

    Cellulose-sponge disk absorbs incoming water and expands with enough force to shut valve. When water recedes, valve opens by squeezing sponge dry to its original size. This direct mechanical action is considered more reliable than solenoid valve.

  10. Mitral Valve Prolapse

    MedlinePlus

    Mitral valve prolapse (MVP) occurs when one of your heart's valves doesn't work properly. The flaps of ... Migraine headaches Chest discomfort Most people who have mitral valve prolapse (MVP) don't need treatment because they ...

  11. Magnetically operated check valve

    NASA Technical Reports Server (NTRS)

    Morris, Brian G. (Inventor); Bozeman, Richard J., Jr. (Inventor)

    1994-01-01

    A magnetically operated check valve is disclosed. The valve is comprised of a valve body and a movable poppet disposed therein. A magnet attracts the poppet to hold the valve shut until the force of fluid flow through the valve overcomes the magnetic attraction and moves the poppet to an unseated, open position. The poppet and magnet are configured and disposed to trap a magnetically attracted particulate and prevent it from flowing to a valve seating region.

  12. Magnetically operated check valve

    NASA Astrophysics Data System (ADS)

    Morris, Brian G.; Bozeman, Richard J., Jr.

    1994-06-01

    A magnetically operated check valve is disclosed. The valve is comprised of a valve body and a movable poppet disposed therein. A magnet attracts the poppet to hold the valve shut until the force of fluid flow through the valve overcomes the magnetic attraction and moves the poppet to an unseated, open position. The poppet and magnet are configured and disposed to trap a magnetically attracted particulate and prevent it from flowing to a valve seating region.

  13. Fast-Acting Valve

    NASA Technical Reports Server (NTRS)

    Wojciechowski, Bogdan V. (Inventor); Pegg, Robert J. (Inventor)

    2003-01-01

    A fast-acting valve includes an annular valve seat that defines an annular valve orifice between the edges of the annular valve seat, an annular valve plug sized to cover the valve orifice when the valve is closed, and a valve-plug holder for moving the annular valve plug on and off the annular valve seat. The use of an annular orifice reduces the characteristic distance between the edges of the valve seat. Rather than this distance being equal to the diameter of the orifice, as it is for a conventional circular orifice, the characteristic distance equals the distance between the inner and outer radii (for a circular annulus). The reduced characteristic distance greatly reduces the gap required between the annular valve plug and the annular valve seat for the valve to be fully open, thereby greatly reducing the required stroke and corresponding speed and acceleration of the annular valve plug. The use of a valve-plug holder that is under independent control to move the annular valve plug between its open and closed positions is important for achieving controllable fast operation of the valve.

  14. Speeding earthquake disaster relief

    USGS Publications Warehouse

    Mortensen, Carl; Donlin, Carolyn; Page, Robert A.; Ward, Peter

    1995-01-01

    In coping with recent multibillion-dollar earthquake disasters, scientists and emergency managers have found new ways to speed and improve relief efforts. This progress is founded on the rapid availability of earthquake information from seismograph networks.

  15. Percutaneous Relief of Tension Pneumomediastinum in a Child

    SciTech Connect

    Chau, Helen Hoi-lun; Kwok, Philip Chong-hei; Lai, Albert Kwok-hung; Fan, Tsz Wo; Chan, Susan Chi-hum; Miu, Ting Yat; Chan, Grace Lai-har

    2003-11-15

    The purpose of this article was to describe the experience of relieving tension pneumomediastinum by a fluoroscopic-guided percutaneous method. We inserted a percutaneous drainage catheter with a Heimlich valve under fluoroscopic guidance to relieve the tension pneumomediastinum in a 2-year-old girl who suffered from dermatomyositis with lung involvement. This allowed immediate relief without the need for surgery. The procedure was repeated for relapsed tension pneumomediastinum. Good immediate results were achieved in each attempt. We conclude that percutaneous relief of pneumomediastinum under fluoroscopic guidance can be performed safely and rapidly in patients not fit for surgery.

  16. A capillary valve for microfluidic systems.

    SciTech Connect

    Cummings, Eric B.; Kanouff, Michael P.; Rush, Brian M.

    2004-10-01

    Microfluidic systems are becoming increasingly complicated as the number of applications grows. The use of microfluidic systems for chemical and biological agent detection, for example, requires that a given sample be subjected to many process steps, which requires microvalves to control the position and transport of the sample. Each microfluidic application has its own specific valve requirements and this has precipitated the wide variety of valve designs reported in the literature. Each of these valve designs has its strengths and weaknesses. The strength of the valve design proposed here is its simplicity, which makes it easy to fabricate, easy to actuate, and easy to integrate with a microfluidic system. It can be applied to either gas phase or liquid phase systems. This novel design uses a secondary fluid to stop the flow of the primary fluid in the system. The secondary fluid must be chosen based on the type of flow that it must stop. A dielectric fluid must be used for a liquid phase flow driven by electroosmosis, and a liquid with a large surface tension should be used to stop a gas phase flow driven by a weak pressure differential. Experiments were carried out investigating certain critical functions of the design. These experiments verified that the secondary fluid can be reversibly moved between its 'valve opened' and 'valve closed' positions, where the secondary fluid remained as one contiguous piece during this transport process. The experiments also verified that when Fluorinert is used as the secondary fluid, the valve can break an electric circuit. It was found necessary to apply a hydrophobic coating to the microchannels to stop the primary fluid, an aqueous electrolyte, from wicking past the Fluorinert and short-circuiting the valve. A simple model was used to develop valve designs that could be closed using an electrokinetic pump, and re-opened by simply turning the pump off and allowing capillary forces to push the secondary fluid back into its

  17. Rotary pneumatic valve

    DOEpatents

    Hardee, Harry C.

    1991-01-01

    A rotary pneumatic valve which is thrust balanced and the pneumatic pressure developed produces only radial loads on the valve cylinder producing negligible resistance and thus minimal torque on the bearings of the valve. The valve is multiplexed such that at least two complete switching cycles occur for each revolution of the cylinder spindle.

  18. Remote actuated valve implant

    DOEpatents

    McKnight, Timothy E; Johnson, Anthony; Moise, Jr., Kenneth J; Ericson, Milton Nance; Baba, Justin S; Wilgen, John B; Evans, III, Boyd McCutchen

    2014-02-25

    Valve implant systems positionable within a flow passage, the systems having an inlet, an outlet, and a remotely activatable valve between the inlet and outlet, with the valves being operable to provide intermittent occlusion of the flow path. A remote field is applied to provide thermal or magnetic activation of the valves.

  19. Dual stage check valve

    NASA Technical Reports Server (NTRS)

    Whitten, D. E. (Inventor)

    1973-01-01

    A dual stage seat valve head arrangement is described which consists of a primary sealing point located between a fixed orifice seat and a valve poppet, and a secondary sealing point between an orifice poppet and a valve poppet. Upstream of the valve orifice is a flexible, convoluted metal diaphragm attached to the orifice poppet. Downstream of the valve orifice, a finger spring exerts a force against the valve poppet, tending to keep the valve in a closed position. The series arrangement of a double seat and poppet is able to tolerate small particle contamination while minimizing chatter by controlling throttling or metering across the secondary seat, thus preserving the primary sealing surface.

  20. Double valve Implantation

    PubMed Central

    Stassano, Paolo; Mannacio, Vito; Musumeci, Antonino; Golino, Alessandro; Maida, Piero; Ferrigno, Vincenzo; Buonocore, Gaetano; Spampinato, Nicola

    1991-01-01

    From January 1976 through December 1987, 194 patients with a mean age of 43.3 ± 13.7 years (range, 11 to 74 years) underwent double (mitral and aortic) replacement of native valves with 8 types of bioprostheses: Carpentier-Edwards, 127 valves; Hancock, 76 valves; Liotta-Bioimplant, 57 valves; Ionescu-Shiley, 53 valves; Vascor, 27 valves; Carpentier-Edwards Pericardial, 22 valves; Angell-Shiley, 20 valves; and Implamedic, 6 valves. Concomitant cardiac procedures were performed in 25 patients (12.8%). There were 18 operative deaths (9.27%). Our retrospective analysis was restricted to 352 bioprostheses implanted in the 176 patients who survived surgery and were considered at risk for valve tissue failure. The overall cumulative duration of follow-up was 1,174.1 patient-years (range, 1 to 13 years). The durations of follow-up for specific valves were: Carpentier-Edwards, 920.2 valve-years; Hancock, 383.8 valve-years; Liotta-Bioimplant, 310.2 valve-years; Ionescu-Shiley, 357.7 valve-years; Vascor, 131.2 valve-years; Carpentier-Edwards Pericardial, 52.0 valve-years; Angell-Shiley, 167.0 valve-years; and Implamedic, 31.0 valve-years. Thirty patients had thromboembolic accidents, for a linearized incidence of 2.5% per patient-year. At 13 years, the actuarial freedom from thromboembolic accidents was 85.8% ± 10.7%. Nine patients had endocarditis, for a linearized incidence of 0.7% per patient-year. At 13 years, the actuarial freedom from endocarditis was 92.0% ± 1.5%. Twenty-four patients had valve tissue failure, for a cumulative linearized incidence of 1.87% per valve-year. The cumulative actuarial probability of freedom from valve tissue failure was 78.6% ± 3.7% at 10 years and 51.2% ± 10.7% at 13 years. The 24 patients with valve tissue failure all underwent reoperation: 20 of these had double valve replacement, 3 had aortic valve replacement alone, and 1 had mitral valve replacement alone. The mean interval between initial valve implantation and reoperation was

  1. Valve-in-Valve Replacement Using a Sutureless Aortic Valve

    PubMed Central

    Dohmen, Pascal M.; Lehmkuhl, Lukas; Borger, Michael A.; Misfeld, Martin; Mohr, Friedrich W.

    2016-01-01

    Patient: Female, 61 Final Diagnosis: Tissue degeneration Symptoms: Dyspnea Medication: — Clinical Procedure: Redo valve replacement Specialty: Surgery Objective: Rare disease Background: We present a unique case of a 61-year-old female patient with homograft deterioration after redo surgery for prosthetic valve endocarditis with root abscess. Case Report: The first operation was performed for type A dissection with root, arch, and elephant trunk replacement of the thoracic aorta. The present re-redo surgery was performed as valve-in-valve with a sutureless aortic biopros-thesis. The postoperative course was uneventful and the patient was discharged on day 6. Conclusions: The current case report demonstrates that sutureless bioprostheses are an attractive option for surgical valve-in-valve procedures, which can reduce morbidity and mortality. PMID:27694795

  2. Joule-Thomson Expander Without Check Valves

    NASA Technical Reports Server (NTRS)

    Chan, C. K.; Gatewood, J. R.

    1989-01-01

    Cooling effected by bidirectional, reciprocating flow of gas. Type of Joule-Thomson (J-T) expander for cryogenic cooling requires no check valves to prevent reverse flow of coolant. More reliable than conventional J-T expander, containing network of check valves, each potential source of failure. Gas flows alternately from left to right and right to left. Heat load cooled by evaporation of liquid from left or right compartment, whichever at lower pressure.

  3. Vacuum breaker valve assembly

    DOEpatents

    Thompson, Jeffrey L.; Upton, Hubert Allen

    1999-04-27

    Breaker valve assemblies for a simplified boiling water nuclear reactor are described. The breaker valve assembly, in one form, includes a valve body and a breaker valve. The valve body includes an interior chamber, and an inlet passage extends from the chamber and through an inlet opening to facilitate transporting particles from outside of the valve body to the interior chamber. The breaker valve is positioned in the chamber and is configured to substantially seal the inlet opening. Particularly, the breaker valve includes a disk which is sized to cover the inlet opening. The disk is movably coupled to the valve body and is configured to move substantially concentrically with respect to the valve opening between a first position, where the disk completely covers the inlet opening, and a second position, where the disk does not completely cover the inlet opening.

  4. Bellows sealed plug valve

    DOEpatents

    Dukas, Jr., Stephen J.

    1990-01-01

    A bellows sealed plug valve includes a valve body having an inlet passage and an outlet passage, a valve chamber between the inlet and outlet passages. A valve plug has substantially the same shape as the valve chamber and is rotatably disposed therein. A shaft is movable linearly in response to a signal from a valve actuator. A bellows is sealingly disposed between the valve chamber and the valve actuator and means are located between the bellows and the valve plug for converting linear movement of the shaft connected to the valve actuator to rotational movement of the plug. Various means are disclosed including helical thread mechanism, clevis mechanism and rack and pinion mechanism, all for converting linear motion to rotational motion.

  5. Scissor thrust valve actuator

    DOEpatents

    DeWall, Kevin G.; Watkins, John C; Nitzel, Michael E.

    2006-08-29

    Apparatus for actuating a valve includes a support frame and at least one valve driving linkage arm, one end of which is rotatably connected to a valve stem of the valve and the other end of which is rotatably connected to a screw block. A motor connected to the frame is operatively connected to a motor driven shaft which is in threaded screw driving relationship with the screw block. The motor rotates the motor driven shaft which drives translational movement of the screw block which drives rotatable movement of the valve driving linkage arm which drives translational movement of the valve stem. The valve actuator may further include a sensory control element disposed in operative relationship with the valve stem, the sensory control element being adapted to provide control over the position of the valve stem by at least sensing the travel and/or position of the valve stem.

  6. Heart valve surgery - series (image)

    MedlinePlus

    There are four valves in the heart: aortic valve, mitral valve, tricuspid valve, and pulmonary valve. The valves are designed to control the direction of blood flow through the heart. The opening and closing of the heart valves produce the heart-beat sounds.

  7. Vitrification of heart valve tissues.

    PubMed

    Brockbank, Kelvin G M; Chen, Zhenzhen; Greene, Elizabeth D; Campbell, Lia H

    2015-01-01

    Application of the original vitrification protocol used for pieces of heart valves to intact heart valves has evolved over time. Ice-free cryopreservation by Protocol 1 using VS55 is limited to small samples where relatively rapid cooling and warming rates are possible. VS55 cryopreservation typically provides extracellular matrix preservation with approximately 80 % cell viability and tissue function compared with fresh untreated tissues. In contrast, ice-free cryopreservation using VS83, Protocols 2 and 3, has several advantages over conventional cryopreservation methods and VS55 preservation, including long-term preservation capability at -80 °C; better matrix preservation than freezing with retention of material properties; very low cell viability, reducing the risks of an immune reaction in vivo; reduced risks of microbial contamination associated with use of liquid nitrogen; improved in vivo functions; no significant recipient allogeneic immune response; simplified manufacturing process; increased operator safety because liquid nitrogen is not used; and reduced manufacturing costs.

  8. Whole Teflon valves for handling droplets.

    PubMed

    Cybulski, Olgierd; Jakiela, Slawomir; Garstecki, Piotr

    2016-06-21

    We propose and test a new whole-Teflon gate valve for handling droplets. The valve allows droplet plugs to pass through without disturbing them. This is possible due to the geometric design, the choice of material and lack of any pulses of flow generated by closing or opening the valve. The duct through the valve resembles a simple segment of tubing, without constrictions, change in lumen or side pockets. There are no extra sealing materials with different wettability or chemical resistance. The only material exposed to liquids is FEP Teflon, which is resistant to aggressive chemicals and fully biocompatible. The valve can be integrated into microfluidic systems: we demonstrate a complex system for culturing bacteria in hundreds of microliter droplet chemostats. The valve effectively isolates modules of the system to increase precision of operations on droplets. We verified that the valve allowed millions of droplet plugs to safely pass through, without any cross-contamination with bacteria between the droplets. The valve can be used in automating complex microfluidic systems for experiments in biochemistry, biology and organic chemistry.

  9. Oral Intake of a Liquid High-Molecular-Weight Hyaluronan Associated with Relief of Chronic Pain and Reduced Use of Pain Medication: Results of a Randomized, Placebo-Controlled Double-Blind Pilot Study

    PubMed Central

    Attridge, Victoria L.; Lenninger, Miki R.; Benson, Kathleen F.

    2015-01-01

    Abstract The goal for this study was to evaluate the effects of daily oral intake of a consumable liquid fermentate containing high-molecular-weight hyaluronan, as well as to perform a basic evaluation of safety and tolerability. A randomized, double-blind placebo-controlled study design was used to examine the effects of oral intake of hyaluronan on chronic pain conditions. Safety assessment included a complete blood count with differential, blood chemistry and electrocardiogram. The study duration was 4 weeks, where three tablespoons (45 mL) product or placebo was ingested during the first 2 weeks, and two tablespoons (30 mL) was consumed during the last 2 weeks. Seventy-eight people between the age of 19 and 71 years enrolled, and 72 people completed the study. Statistical analysis was performed using the two-tailed independent t-test for between-group significance and using the paired t-test for within-group significance. A reduction in pain scores was seen after 2 weeks of consumption of both placebo (P<.1) and active (P<.065) product; the reduction was more pronounced in the group consuming the active test product. Using “within-subject” analysis, a highly significant reduction in chronic pain scores was seen after 2 weeks of consumption of three tablespoons of active product (P<.001), whereas only a mild nonsignificant reduction in pain scores was seen in the placebo group. During the reduced intake for the last 2 weeks of study participation, pain scores showed a slight increase. During the last 2 weeks, a significant increase in the quality of sleep (P<.005) and level of physical energy (P<.05) was seen. The pain reduction during the initial 2 weeks was associated with significant reduction in the use of pain medication (P<.05). Consumption of an oral liquid formula containing high-molecular-weight hyaluronan was associated with relief of chronic pain. PMID:25415767

  10. Magnetically operated check valve

    NASA Astrophysics Data System (ADS)

    Morris, Brian G.; Bozeman, Richard J., Jr.

    1993-03-01

    A magnetically operated check valve is disclosed having, in one aspect, a valve body and a movable poppet disposed therein. A magnet attracts the poppet to hold the valve shut until the force of fluid flow through the valve overcomes the magnetic attraction and moves the poppet to an unseated, open position. The poppet and magnet are configured and disposed to trap a magnetically attracted particulate and prevent it from flowing to a valve seating region.

  11. Liquid Level Control System.

    DTIC Science & Technology

    A system for controlling liquid flow from an inlet into a tank comprising a normally closed poppet valve controlled by dual pressure chambers each...containing a diaphragm movable by the pressure of the liquid in the inlet to cause the valve to close. Pressure against the diaphragms is relieved by

  12. When a Heart Murmur Signals Valve Disease

    MedlinePlus

    ... Problem: Valve Stenosis - Problem: Aortic Valve Stenosis - Problem: Mitral Valve Stenosis - Problem: Tricuspid Valve Stenosis - Problem: Pulmonary Valve Stenosis Problem: Mitral Valve Prolapse Problem: Heart Valve Regurgitation - Problem: Aortic ...

  13. Transcatheter Mitral Valve Repair Therapies: Evolution, Status and Challenges.

    PubMed

    Espiritu, Daniella; Onohara, Daisuke; Kalra, Kanika; Sarin, Eric L; Padala, Muralidhar

    2017-02-01

    Mitral regurgitation is a common cardiac valve lesion, developing from primary lesions of the mitral valve or secondary to cardiomyopathies. Moderate or higher severity of mitral regurgitation imposes significant volume overload on the left ventricle, causing permanent structural and functional deterioration of the myocardium and heart failure. Timely correction of regurgitation is essential to preserve cardiac function, but surgical mitral valve repair is often delayed due to the risks of open heart surgery. Since correction of mitral regurgitation can provide symptomatic relief and halt progressive cardiac dysfunction, transcatheter mitral valve repair technologies are emerging as alternative therapies. In this approach, the mitral valve is repaired either with sutures or implants that are delivered to the native valve on catheters introduced into the cardiovascular system under image guidance, through small vascular or ventricular ports. Several transcatheter mitral valve technologies are in development, but limited clinical success has been achieved. In this review, we present a historical perspective of mitral valve repair, review the transcatheter technologies emerging from surgical concepts, the challenges they face in achieving successful clinical application, and the increasing rigor of safety and durability standards for new transcatheter valve technologies.

  14. Hydraulically actuated gas exchange valve assembly and engine using same

    DOEpatents

    Carroll, Thomas S.; Taylor, Gregory O.

    2002-09-03

    An engine comprises a housing that defines a hollow piston cavity that is separated from a gas passage by a valve seat. The housing further defines a biasing hydraulic cavity and a control hydraulic cavity. A gas valve member is also included in the engine and is movable relative to the valve seat between an open position at which the hollow piston cavity is open to the gas passage and a closed position in which the hollow piston cavity is blocked from the gas passage. The gas valve member includes a ring mounted on a valve piece and a retainer positioned between the ring and the valve piece. A closing hydraulic surface is included on the gas valve member and is exposed to liquid pressure in the biasing hydraulic cavity.

  15. Fast acting check valve

    NASA Technical Reports Server (NTRS)

    Perkins, Gerald S. (Inventor)

    1979-01-01

    A check valve which closes more rapidly to prevent wearing of the valve seat and of the valve member that seals thereagainst, including a solenoid or other actuator that aids the normal spring to quickly close the valve at approximately the time when downpath fluid flow would stop, the actuator then being deenergized. The control circuit that operates the actuator can include a pair of pressure sensors sensing pressure both upstream and downstream from the valve seat. Where the valve is utilized to control flow to or from a piston pump, energization of the actuator can be controlled by sensing when the pump piston reaches its extreme of travel.

  16. Quickly Removable Valve

    NASA Technical Reports Server (NTRS)

    Robbins, John S.

    1988-01-01

    Unit removed with minimal disturbance. Valve inlet and outlet ports adjacent to each other on same side of valve body. Ports inserted into special manifold on fluid line. Valve body attached to manifold by four bolts or, alternatively, by toggle clamps. Electromechanical actuator moves in direction parallel to fluid line to open and close valve. When necessary to clean valve, removed simply by opening bolts or toggle clamps. No need to move or separate ports of fluid line. Valve useful where disturbance of fluid line detrimental or where fast maintenance essential - in oil and chemical industries, automotive vehicles, aircraft, and powerplants.

  17. Ball valve extractor

    DOEpatents

    Herndon, Charles; Brown, Roger A.

    2002-01-01

    An apparatus and process for removing a ball valve is provided. The ball valve removal tool provides a handle sliding along the length of a shaft. One end of the shaft is secured within an interior cavity of a ball valve while the opposite end of the shaft defines a stop member. By providing a manual sliding force to the handle, the handle impacts the stop member and transmits the force to the ball valve. The direction of the force is along the shaft of the removal tool and disengages the ball valve from the ball valve housing.

  18. Living with Heart Valve Disease

    MedlinePlus

    ... page from the NHLBI on Twitter. Living With Heart Valve Disease Heart valve disease is a lifelong condition. However, ... all of your medicines as prescribed. Pregnancy and Heart Valve Disease Mild or moderate heart valve disease during pregnancy ...

  19. Valve mechanism having variable valve timing

    SciTech Connect

    Oda, H.; Masuda, S.; Morita, Y.

    1986-04-08

    This patent describes a valve mechanism for an internal combustion engine which consists of a camshaft rotatable about a longitudinal axis and having a cam formed thereon, a swingable member mounted for swinging movement about the longitudinal axis of the camshaft and formed with a tappet receiving hole. A valve tapper is received in the tappet receiving hole for a slidable movement along the tappet receiving hole. The tappet has a cam which engages the surface at one end and a stem engages the surface at the other end. A valve stem is mounted for axial movement and engaged at one end with the stem engaging, surface of the tappet to be actuated thereby. A valve timing control swingably moves the swingable member and the tappet about the camshaft axis in accordance with predetermined engine operating conditions to thereby change valve opening and valve closing timing. The control includes means for holding the swingable member at a first position. The tappet and valve stem are in contact at a first position on the stem engaging surface of the tappet and the direction of the slidable movement of the tappet is aligned with the direction of the axial movement of the valve stem at least under heavy load, high speed engine operation, and for moving the swingable member from the first position to a second position. The tappet and valve stem are in contact at a second position on the stem engaging surface of the tappet at low speed engine operation to effect a change in valve opening and valve closing timing.

  20. Monitoring circuit accurately measures movement of solenoid valve

    NASA Technical Reports Server (NTRS)

    Gillett, J. D.

    1966-01-01

    Solenoid operated valve in a control system powered by direct current issued to accurately measure the valve travel. This system is currently in operation with a 28-vdc power system used for control of fluids in liquid rocket motor test facilities.

  1. Pump isolation valve

    DOEpatents

    Kinney, Calvin L.; Wetherill, Todd M.

    1983-08-02

    The pump isolation valve provides a means by which the pump may be selectively isolated from the remainder of the coolant system while being compatible with the internal hydraulic arrangement of the pump during normal operation of the pump. The valve comprises a valve cylinder disposed around the pump and adjacent to the last pump diffuser with a turning vane attached to the lower end of the valve cylinder in a manner so as to hydraulically match with the discharge diffuser. The valve cylinder is connected to a drive means for sliding the valve cylinder relative to the diffuser support cylinder so as to block flow in either direction through the discharge diffuser when the valve is in the closed position and to aid in the flow of the coolant from the discharge diffuser by means of the turning vane when the valve is in the open position.

  2. Problem: Mitral Valve Regurgitation

    MedlinePlus

    ... Options • Recovery and Healthy Living Goals • Personal Stories Heart Valve Disease Symptoms Dr. Robert Bonow describes the symptoms that may alert you to heart valve disease. Support Network: You're Not Alone Popular Articles ...

  3. Problem: Heart Valve Regurgitation

    MedlinePlus

    ... Options • Recovery and Healthy Living Goals • Personal Stories Heart Valve Disease Symptoms Dr. Robert Bonow describes the symptoms that may alert you to heart valve disease. Support Network: You're Not Alone Popular Articles ...

  4. Aortic Valve Disease

    MedlinePlus

    ... Ventricle Normal Heart Select Disease To Learn More Aortic Stenosis Aortic Insufficiency Aorta The aorta is the main ... the rest of your body. Aortic Valve In aortic stenosis, the aortic valve becomes narrowed and does not ...

  5. Aortic Valve Stenosis

    MedlinePlus

    ... By Mayo Clinic Staff Aortic valve stenosis — or aortic stenosis — occurs when the heart's aortic valve narrows. This ... pressure may prevent or slow the development of aortic stenosis. Ask your doctor if you need to lower ...

  6. Stemless Ball Valve

    NASA Technical Reports Server (NTRS)

    Burgess, Robert K.; Yakos, David; Walthall, Bryan

    2012-01-01

    This invention utilizes a new method of opening and closing a ball valve. Instead of rotating the ball with a perpendicular stem (as is the case with standard ball valves), the ball is rotated around a fixed axis by two guide pins. This innovation eliminates the leak point that is present in all standard ball valves due to the penetration of an actuation stem through the valve body. The VOST (Venturi Off-Set-Technology) valve has been developed for commercial applications. The standard version of the valve consists of an off-set venturi flow path through the valve. This path is split at the narrowest portion of the venturi, allowing the section upstream from the venturi to be rotated. As this rotation takes place, the venturi becomes restricted as one face rotates with respect to the other, eventually closing off the flow path. A spring-loaded seal made of resilient material is embedded in the upstream face of the valve, making a leak-proof seal between the faces; thus a valve is formed. The spring-loaded lip seal is the only seal that can provide a class six, or bubble-tight, seal against the opposite face of the valve. Tearing action of the seal by high-velocity gas on this early design required relocation of the seal to the downstream face of the valve. In the stemless embodiment of this valve, inner and outer magnetic cartridges are employed to transfer mechanical torque from the outside of the valve to the inside without the use of a stem. This eliminates the leak path caused by the valve stems in standard valves because the stems penetrate through the bodies of these valves.

  7. Aerodynamic Shutoff Valve

    NASA Technical Reports Server (NTRS)

    Horstman, Raymond H.

    1992-01-01

    Aerodynamic flow achieved by adding fixed fairings to butterfly valve. When valve fully open, fairings align with butterfly and reduce wake. Butterfly free to turn, so valve can be closed, while fairings remain fixed. Design reduces turbulence in flow of air in internal suction system. Valve aids in development of improved porous-surface boundary-layer control system to reduce aerodynamic drag. Applications primarily aerospace. System adapted to boundary-layer control on high-speed land vehicles.

  8. Valve technology: A compilation

    NASA Technical Reports Server (NTRS)

    1971-01-01

    A technical compilation on the types, applications and modifications to certain valves is presented. Data cover the following: (1) valves that feature automatic response to stimuli (thermal, electrical, fluid pressure, etc.), (2) modified valves changed by redesign of components to increase initial design effectiveness or give the item versatility beyond its basic design capability, and (3) special purpose valves with limited application as presented, but lending themselves to other uses with minor changes.

  9. Heart Valve Diseases

    MedlinePlus

    Your heart has four valves. Normally, these valves open to let blood flow through or out of your heart, and then shut to keep it from flowing ... close tightly. It's one of the most common heart valve conditions. Sometimes it causes regurgitation. Stenosis - when ...

  10. Mitral Valve Prolapse

    PubMed Central

    Rosser, Walter W.

    1992-01-01

    The author discusses the pathophysiology of mitral valve prolapse and provides guidelines to identify and treat low-to high-risk mitral valve prolapse. An approach to diagnosing bacterial endocarditis and its prophylaxis are also discussed. The author reviews mitral valve prolapse syndrome and the risk of sudden death.

  11. Double-Poppet Valve

    NASA Technical Reports Server (NTRS)

    Huber, W. C.

    1984-01-01

    New valve design includes two poppet/seat combinations actuated simultaneously. If one fails, other continues to seal against fluid flow. Valve primarily useful for handling dangerous fluids and lighter and more compact than comparable redundant-valve systems used at present.

  12. Dump valve assembly

    DOEpatents

    Owen, T.J.

    1984-01-01

    A dump valve assembly comprising a body having a bore defined by a tapered wall and a truncated spherical valve member adapted to seat along a spherical surface portion thereof against said tapered wall. Means are provided for pivoting said valve member between a closed position engagable with said tapered wall and an open position disengaged therefrom.

  13. Well safety valve

    SciTech Connect

    Vinzant, M.B.; Hilts, R.L.; Meaders, M.; Speegle, S.C.

    1984-07-24

    A retrievable well safety valve in a cased well system including a tubing string, a dual packer downhole around the tubing sealing with the casing and submersible pump in the tubing string below the packer. The safety valve controls flow of pumped fluids through the tubing to surface and directs gas flow into the casing annulus above the packer. When the safety valve is landed in cooperating tubing nipples above the packer, separated central annular flow passages are formed for pumped fluids and gas respectively. A ball valve in the central flow passage controls pumped fluid flow therethrough and an annular valve coupled to the ball valve controls gas flow from below the packer through the annular flow passage around and by the ball valve. When the ball valve is in the down and open position, the valve ball member engages a lower seat, which maintains the central and annular flow passages separate and prevents comingling flow of fluids and gas. The coupled valves are held open by pressured fluid from surface and are closed automatically on loss of pressure in their control fluid circuits. When the valves close, a circuit of flow passages for recirculating pumped fluids and gas are opened below the ball valve and the pump may continue operation without overload.

  14. Microblower assisted barometric valve

    DOEpatents

    Rossabi, Joseph; Hyde, Warren K.; Riha, Brian D.; Jackson, Dennis G.; Sappington, Frank

    2005-12-06

    A gas exchange apparatus is provided which provides for both passive fluid flow and blower associated fluid flow through a barometric valve. A battery powered blower is provided which allows for operation of the barometric valve during times when the barometric valve would otherwise be closed, and provides for enhanced volume of gas exchange.

  15. Lock For Valve Stem

    NASA Technical Reports Server (NTRS)

    Burley, Richard K.; Guirguis, Kamal S.

    1991-01-01

    Simple, cheap device locks valve stem so its setting cannot be changed by unauthorized people. Device covers valve stem; cover locked in place with standard padlock. Valve lock made of PVC pipe and packing band. Shears, drill or punch, and forming rod only tools needed.

  16. How Is Mitral Valve Prolapse Treated?

    MedlinePlus

    ... page from the NHLBI on Twitter. How Is Mitral Valve Prolapse Treated? Most people who have mitral valve ... all hospitals offer this method. Valve Repair and Valve Replacement In mitral valve surgery, the valve is repaired or replaced. ...

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

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... liquid flow rates. All valves must be made from approved materials compatible with the lading and having... Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS SPECIFICATIONS FOR TANK...

  18. The relief of mitral stenosis. An historic step in cardiac surgery.

    PubMed Central

    Khan, M N

    1996-01-01

    Significant progress has been achieved in cardiac surgery in the last 50 years. Mitral valve surgery (especially for the relief of mitral stenosis) has paralleled the innovations and trends of cardiac surgery and often has served as the benchmark of the latest procedures and techniques. A chronological survey of mitral valve surgery is presented, with emphasis on parallels to cardiac surgery in general and with highlights of key figures and events that have conclusively altered the surgeon's approach to and success with cardiac dysfunction. A few surgeons promulgated the idea of cardiac surgery in the late 19th century, but mitral valve surgeries were not performed in earnest until Souttar's and Cutler's initial attempts in the 1920s and were not successful on large groups of patients until Bailey and Harken made independent breakthroughs in the 1940s, finally laying to rest the idea of the "inviolable heart." Cardiopulmonary bypass provided cardiac surgeons with the time to implant mechanical and bioprosthetic valves for palliative benefit to patients. The "perfect" valve has yet to be found, but the Starr-Edwards mechanical valve since its inception in 1961 has been one of the most successful and widely used prosthetic valves. Gradual improvement in surgical technique and growing knowledge of valve function enabled the re-emergence of mitral valve repair in the 1980s as the preferred surgical method of treating mitral stenosis. In the last 10 years, mitral valve balloon dilation has provided a nonsurgical technique for relief of stenosis and represents the broader trend towards interventional techniques. Images PMID:8969024

  19. Rapid-Chill Cryogenic Coaxial Direct-Acting Solenoid Valve

    NASA Technical Reports Server (NTRS)

    Richard, James; Castor, Jim; Sheller, Richard

    2006-01-01

    A commercially available cryogenic direct- acting solenoid valve has been modified to incorporate a rapid-chill feature. The net effect of the modifications is to divert some of the cryogenic liquid to the task of cooling the remainder of the cryogenic liquid that flows to the outlet. Among the modifications are the addition of several holes and a gallery into a valve-seat retainer and the addition of a narrow vent passage from the gallery to the atmosphere.

  20. A new real-time non-coherent to coherent light image converter - The hybrid field effect liquid crystal light valve

    NASA Technical Reports Server (NTRS)

    Grinberg, J.; Jacobson, A.; Bleha, W.; Miller, L.; Fraas, L.; Boswell, D.; Myer, G.

    1975-01-01

    A new, high-performance device has been developed for application to real-time coherent optical data processing. The new device embodies a CdS photoconductor, a CdTe light-absorbing layer, a dielectric mirror, and a liquid crystal layer sandwiched between indium-tin-oxide transparent electrodes deposited on optical quality glass flats. The noncoherent image is directed onto the photoconductor; this reduces the impedance of the photoconductor, thereby switching the ac voltage that is impressed across the electrodes onto the liquid crystal to activate the device. The liquid crystal is operated in a hybrid field effect mode. It utilizes the twisted nematic effect to create a dark off-state and the optical birefringence effect to create the bright on-state. The liquid crystal modulates the polarization of the coherent read-out light so an analyzer must be used to create an intensity modulated output beam.

  1. 49 CFR 195.116 - Valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Valves. 195.116 Section 195.116 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS...

  2. Approaching cancer pain relief.

    PubMed

    Lickiss, J N

    2001-01-01

    Pain is defined as an unpleasant experience-it is subjective and achieving pain relief is achieving a change in the patient's experience. There needs to be an adequate concept of a human person (an ecological model will be discussed) and a logical process for approaching pain relief in an individual patient (e.g. the plan used in the Sydney Institute of Palliative Medicine). Communication with the patient is critical to get a grasp of him or her as a person, their environment, personal experience and cultural background. Then encourage him or her to tell the story of the cancer saga as they perceive it, listening carefully for the matters which may have given rise to acute distress (for example, delay in diagnosis) and how they adjusted to this. The individual is conveying a great deal about him or herself as they tell their story. Next the story of the treatment and their experience of it, and then the response of their tumour to it--then the story of their pain: when it began, its characteristics, how it evolved, what factors worsen the pain, what relieves it, etc. This is followed by careful clinical examination to clarify what could be the most likely mechanism(s) responsible for the noxious stimulus. Some investigation (e.g. X-ray) may be justified to assist clarification--but not before making a clinical diagnosis (best guess) and commencing treatment with drugs or other logical measures with some local action--depending on the most probable mechanism. Paracetamol/non-steroidal anti-inflammatory drugs (NSAIDs) etc may be logical. Threshold factors should be attended to--comfort, concern always, or anxiolytic or antidepressant drugs if the patient is pathologically anxious or depressed. The opioid drugs--with morphine still as the gold standard--should be appropriately used. This involves careful calibration of dose (below sedative level) normally with an immediate-release, preparation--and, in the case of morphine, specific counselling concerning 'myths' to

  3. CAM operated fuel valve

    SciTech Connect

    Kelly, S.T.; Katchka, J.R.

    1991-09-03

    This patent describes improvement in a fuel control valve construction comprising a housing means having an inlet means adapted to be interconnected to a fuel source and a main outlet means adapted to be interconnected to a main burner means, the housing means having a main valve seat for interconnecting the inlet means with the main outlet means, the housing means having a movable main valve member for opening and closing the main valve seat, the housing means having a movable lever operatively associated with the main valve member and having a manually operable actuator means for controlling the operating positions of the lever, the lever having an intermediate cam follower portion and opposed ends disposed on each side of the cam follower portion with one end of the opposed ends being pivotally mounted to the housing means and with the other end of the opposed ends for operating the main valve member, the housing means having biasing means operatively interconnected to the lever to tend to pivot the lever in one direction that opens the main valve member away from its the main valve seat. The improvement comprises; the housing means has a thermostatically controlled means that is operatively associated with the lever and is adapted to engage and hold the lever in a position wherein the main valve member is in a closed condition against its the main valve seat when the thermostatically controlled means is in one operating condition thereof and the actuator means is in the on condition thereof.

  4. Valve selection in aortic valve endocarditis

    PubMed Central

    Zubrytska, Yana

    2016-01-01

    Aortic prosthetic valve endocarditis (PVE) is a potentially life-threatening disease. Mortality and incidence of infective endocarditis have been reduced in the past 30 years. Medical treatment of aortic PVE may be successful in patients who have a prompt response after antibiotic treatment and who do not have prosthetic dysfunction. In advanced stages, antibiotic therapy alone is insufficient to control the disease, and surgical intervention is necessary. Surgical treatment may be lifesaving, but it is still associated with considerable morbidity and mortality. The aim of surgery is to perform a radical excision of all infected and necrotic tissue, reconstruction of the left ventricle outflow tract, and replacement of the aortic valve. There is no unanimous consensus on which is the optimal prosthesis to implant in this context, and several surgical techniques have been suggested. We aim to analyze the efficacy of the surgical treatment and discuss the issue of valve selection in patients with aortic valve endocarditis. PMID:27785132

  5. Guide to prosthetic cardiac valves

    SciTech Connect

    Morse, D.; Steiner, R.M.; Fernandez, J.

    1985-01-01

    This book contains 10 chapters. Some of the chapter titles are: The development of artificial heart valves: Introduction and historical perspective; The radiology of prosthetic heart valves; The evaluation of patients for prosthetic valve implantation; Pathology of cardiac valve replacement; and Bioengineering of mechanical and biological heart valve substitutes.

  6. What Is Heart Valve Disease?

    MedlinePlus

    ... flow properly. Acquired heart valve disease usually involves aortic or mitral valves. Although the valves are normal at first, problems develop over time. Both congenital and acquired heart valve disease can cause stenosis or backflow. Outlook Many people have heart valve ...

  7. Cryogenic Cam Butterfly Valve

    NASA Technical Reports Server (NTRS)

    McCormack, Kenneth J. (Inventor)

    2016-01-01

    A cryogenic cam butterfly valve has a body that includes an axially extending fluid conduit formed there through. A disc lug is connected to a back side of a valve disc and has a circular bore that receives and is larger than a cam of a cam shaft. The valve disc is rotatable for a quarter turn within the body about a lug axis that is offset from the shaft axis. Actuating the cam shaft in the closing rotational direction first causes the camming side of the cam of the cam shaft to rotate the disc lug and the valve disc a quarter turn from the open position to the closed position. Further actuating causes the camming side of the cam shaft to translate the valve disc into sealed contact with the valve seat. Opening rotational direction of the cam shaft reverses these motions.

  8. Minimally invasive valve surgery.

    PubMed

    Woo, Y Joseph; Seeburger, Joerg; Mohr, Friedrich W

    2007-01-01

    As alternatives to standard sternotomy, surgeons have developed innovative, minimally invasive approaches to conducting valve surgery. Through very small skin incisions and partial upper sternal division for aortic valve surgery and right minithoracotomy for mitral surgery, surgeons have become adept at performing complex valve procedures. Beyond cosmetic appeal, apparent benefits range from decreased pain and bleeding to improved respiratory function and recovery time. The large retrospective studies and few small prospective randomized studies are herein briefly summarized. The focus is then directed toward describing specific intraoperative technical details in current clinical use, covering anesthetic preparation, incision, mediastinal access, cardiovascular cannulation, valve exposure, and valve reconstruction. Finally, unique situations such as pulmonic valve surgery, reoperations, beating heart surgery, and robotics are discussed.

  9. Intelligent Flow Control Valve

    NASA Technical Reports Server (NTRS)

    Kelley, Anthony R (Inventor)

    2015-01-01

    The present invention is an intelligent flow control valve which may be inserted into the flow coming out of a pipe and activated to provide a method to stop, measure, and meter flow coming from the open or possibly broken pipe. The intelligent flow control valve may be used to stop the flow while repairs are made. Once repairs have been made, the valve may be removed or used as a control valve to meter the amount of flow from inside the pipe. With the addition of instrumentation, the valve may also be used as a variable area flow meter and flow controller programmed based upon flowing conditions. With robotic additions, the valve may be configured to crawl into a desired pipe location, anchor itself, and activate flow control or metering remotely.

  10. JenaValve.

    PubMed

    Treede, Hendrik; Rastan, Ardawan; Ferrari, Markus; Ensminger, Stephan; Figulla, Hans-Reiner; Mohr, Friedrich-Wilhelm

    2012-09-01

    The JenaValve is a next-generation TAVI device which consists of a well-proven porcine root valve mounted on a low-profile nitinol stent. Feeler guided positioning and clip fixation on the diseased leaflets allow for anatomically correct implantation of the device without rapid pacing. Safety and efficacy of transapical aortic valve implantation using the JenaValve were evaluated in a multicentre prospective study that showed good short and midterm results. The valve was CE-mark released in Europe in September 2011. A post-market registry ensures on-going and prospective data collection in "real-world" patients. The transfemoral JenaValve delivery system will be evaluated in a first-in-man study in the near future.

  11. Aging assessment of the boiling-water reactor (BWR) standby liquid control system. Phase 1

    SciTech Connect

    Orton, R.D.; Johnson, A.B.; Buckley, G.D.; Larson, L.L.

    1992-10-01

    Pacific Northwest Laboratory conducted a Phase I aging assessment of the standby liquid control (SLC) system used in boiling-water reactors. The study was based on detailed reviews of SLC system component and operating experience information obtained from the Nuclear Plant Reliability Database System, the Nuclear Document System, Licensee Event Reports, and other databases. Sources dealing with sodium pentaborate, borates, boric acid, and the effects of environment and corrosion in the SLC system were reviewed to characterize chemical properties and corrosion characteristics of borated solutions. The leading aging degradation concern to date appears to be setpoint drift in relief valves, which has been discovered during routine surveillance and is thought to be caused by mechanical wear. Degradation was also observed in pump seals and internal valves. In general, however, the results of the Phase I study suggest that age-related degradation of SLC systems has not been serious.

  12. Aging assessment of the boiling-water reactor (BWR) standby liquid control system

    SciTech Connect

    Orton, R.D.; Johnson, A.B.; Buckley, G.D.; Larson, L.L.

    1992-10-01

    Pacific Northwest Laboratory conducted a Phase I aging assessment of the standby liquid control (SLC) system used in boiling-water reactors. The study was based on detailed reviews of SLC system component and operating experience information obtained from the Nuclear Plant Reliability Database System, the Nuclear Document System, Licensee Event Reports, and other databases. Sources dealing with sodium pentaborate, borates, boric acid, and the effects of environment and corrosion in the SLC system were reviewed to characterize chemical properties and corrosion characteristics of borated solutions. The leading aging degradation concern to date appears to be setpoint drift in relief valves, which has been discovered during routine surveillance and is thought to be caused by mechanical wear. Degradation was also observed in pump seals and internal valves. In general, however, the results of the Phase I study suggest that age-related degradation of SLC systems has not been serious.

  13. Aortic or Mitral Valve Replacement With the Biocor and Biocor Supra

    ClinicalTrials.gov

    2016-03-09

    Aortic Valve Insufficiency; Aortic Valve Regurgitation; Aortic Valve Stenosis; Aortic Valve Incompetence; Mitral Valve Insufficiency; Mitral Valve Regurgitation; Mitral Valve Stenosis; Mitral Valve Incompetence

  14. [Modern mitral valve surgery].

    PubMed

    Bothe, W; Beyersdorf, F

    2016-04-01

    At the beginning of the 20th century, Cutler and Levine performed the first successful surgical treatment of a stenotic mitral valve, which was the only treatable heart valve defect at that time. Mitral valve surgery has evolved significantly since then. The introduction of the heart-lung machine in 1954 not only reduced the surgical risk, but also allowed the treatment of different mitral valve pathologies. Nowadays, mitral valve insufficiency has become the most common underlying pathomechanism of mitral valve disease and can be classified into primary and secondary mitral insufficiency. Primary mitral valve insufficiency is mainly caused by alterations of the valve (leaflets and primary order chords) itself, whereas left ventricular dilatation leading to papillary muscle displacement and leaflet tethering via second order chords is the main underlying pathomechanism for secondary mitral valve regurgitation. Valve reconstruction using the "loop technique" plus annuloplasty is the surgical strategy of choice and normalizes life expectancy in patients with primary mitral regurgitation. In patients with secondary mitral regurgitation, implanting an annuloplasty is not superior to valve replacement and results in high rates of valve re-insufficiency (up to 30 % after 3 months) due to ongoing ventricular dilatation. In order to improve repair results in these patients, we add a novel subvalvular technique (ring-noose-string) to the annuloplasty that aims to prevent ongoing ventricular remodeling and re-insufficiency. In modern mitral surgery, a right lateral thoracotomy is the approach of choice with excellent repair and cosmetic results.

  15. Passively actuated valve

    SciTech Connect

    Modro, S. Michael; Ougouag, Abderrafi M.

    2005-09-20

    A passively actuated valve for isolating a high pressure zone from a low pressure zone and discontinuing the isolation when the pressure in the high pressure zone drops below a preset threshold. If the pressure in the high pressure zone drops below the preset threshold, the valve opens and allows flow from the high pressure zone to the low pressure zone. The valve remains open allowing pressure equalization and back-flow should a pressure inversion between the two pressure zone occur.

  16. Transventricular mitral valve operations.

    PubMed

    Joseph Woo, Y; McCormick, Ryan C

    2011-10-01

    We report transventricular mitral valve operations in 2 patients with severe mitral regurgitation and postinfarction left ventricular rupture and pseudoaneurysm. The first patient had direct papillary muscle involvement necessitating replacement of the mitral valve. The second patient had indirect mitral involvement allowing for placement of an atrial mitral annuloplasty ring via the left ventricle. Both patients showed no mitral valve regurgitation after replacement or repair and had uneventful postoperative recoveries. These cases demonstrate a feasible, alternative, transventricular approach to mitral valve replacement and repair.

  17. Compact gate valve

    DOEpatents

    Bobo, Gerald E.

    1977-01-01

    This invention relates to a double-disc gate valve which is compact, comparatively simple to construct, and capable of maintaining high closing pressures on the valve discs with low frictional forces. The valve casing includes axially aligned ports. Mounted in the casing is a sealed chamber which is pivotable transversely of the axis of the ports. The chamber contains the levers for moving the valve discs axially, and an actuator for the levers. When an external drive means pivots the chamber to a position where the discs are between the ports and axially aligned therewith, the actuator for the levers is energized to move the discs into sealing engagement with the ports.

  18. Magnetic Check Valve

    NASA Technical Reports Server (NTRS)

    Morris, Brian G.; Bozeman, Richard J., Jr.

    1994-01-01

    Poppet in proposed check valve restored to closed condition by magnetic attraction instead of spring force. Oscillations suppressed, with consequent reduction of wear. Stationary magnetic disk mounted just upstream of poppet, also containing magnet. Valve body nonmagnetic. Forward pressure or flow would push poppet away from stationary magnetic disk so fluid flows easily around poppet. Stop in valve body prevents poppet from being swept away. When flow stopped or started to reverse, magnetic attraction draws poppet back to disk. Poppet then engages floating O-ring, thereby closing valve and preventing reverse flow. Floating O-ring facilitates sealing at low loads.

  19. Engine valve driving apparatus

    SciTech Connect

    Masuda, S.; Uesugi, T.; Oda, H.

    1989-01-03

    An engine valve driving apparatus for an internal combustion engine having a cam driven engine valve is described. It consists of a camshaft rotatable in synchronism with rotation of a crankshaft of an engine and a movable cam member supported by the camshaft for axial movement and prevented from turning relative to the camshaft. The movable cam member can be axially shifted between an operative position wherein the cam member is cooperative with a member of the engine valve so as to cause an operation of the engine valve and an inoperative position wherein the cam member is out of cooperation with the member.

  20. Modeling the Mitral Valve

    NASA Astrophysics Data System (ADS)

    Kaiser, Alexander

    2016-11-01

    The mitral valve is one of four valves in the human heart. The valve opens to allow oxygenated blood from the lungs to fill the left ventricle, and closes when the ventricle contracts to prevent backflow. The valve is composed of two fibrous leaflets which hang from a ring. These leaflets are supported like a parachute by a system of strings called chordae tendineae. In this talk, I will describe a new computational model of the mitral valve. To generate geometry, general information comes from classical anatomy texts and the author's dissection of porcine hearts. An MRI image of a human heart is used to locate the tips of the papillary muscles, which anchor the chordae tendineae, in relation to the mitral ring. The initial configurations of the valve leaflets and chordae tendineae are found by solving solving an equilibrium elasticity problem. The valve is then simulated in fluid (blood) using the immersed boundary method over multiple heart cycles in a model valve tester. We aim to identify features and mechanisms that influence or control valve function. Support from National Science Foundation, Graduate Research Fellowship Program, Grant DGE 1342536.

  1. What Causes Heart Valve Disease?

    MedlinePlus

    ... page from the NHLBI on Twitter. What Causes Heart Valve Disease? Heart conditions and other disorders, age-related changes, ... valve disease. Other Conditions and Factors Linked to Heart Valve Disease Many other conditions and factors are linked to ...

  2. Options for Heart Valve Replacement

    MedlinePlus

    ... which may include human or animal donor tissue) Ross Procedure — “Borrowing” your healthy valve and moving it ... Considerations for Surgery Medications Valve Repair Valve Replacement - Ross Procedure - Newer Surgery Options - What is TAVR? - Types ...

  3. 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.

  4. 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.

  5. 19 CFR 172.2 - Petition for relief.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 2 2011-04-01 2011-04-01 false Petition for relief. 172.2 Section 172.2 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY... for liquidated damages or remission or mitigation of a fine or penalty secured by a Customs...

  6. Valve mechanisms for at least two simultaneously actuable valves

    SciTech Connect

    Heimburg, F.

    1989-02-21

    This patent describes a valve gear for at least two valves of an internal combustion engine to be operated simultaneously on longitudinal axes, wherein the valve gear comprises a thrust device which is common to all valves and displaceable on an axis by a cam shaft and against which the valves abut by their valve stems to that displacement of the thrust device causes corresponding displacement of the valves, characterized in that the camshaft includes a single cam that is seated on the thrust device eccentrically relative to its axis causing rotation of the thrust device about its axis. When the thrust device is displaced, the thrust device is axially symmetrical, and the valve stems each abut against the thrust device at positions centered on points offset from the longitudinal axes of the valves causing rotation of the valves about their longitudinal axis when the valves are displaced.

  7. Understanding Heart Valve Problems and Causes

    MedlinePlus

    ... affecting the aortic valve, and can lead to aortic stenosis . Mediastinal radiation therapy (radiation to the chest) – Studies ... Disease "Innocent" Heart Murmur Problem: Valve Stenosis - Problem: Aortic Valve Stenosis - Problem: Mitral Valve Stenosis - Problem: Tricuspid Valve Stenosis - ...

  8. How Is Heart Valve Disease Treated?

    MedlinePlus

    ... and replacing it with a man-made or biological valve. Biological valves are made from pig, cow, or human ... the valve. Man-made valves last longer than biological valves and usually don’t have to be ...

  9. A cryogenic valve for spacecraft applications

    NASA Technical Reports Server (NTRS)

    Salerno, L. J.; Spivak, A. L.

    1982-01-01

    Space-compatible cryogenic valves are now required to operate between room and liquid helium temperatures. A remotely controllable cryogenic valve is described, which is made of bellows-type stainless steel and is operated by a miniature dc motor with integral gearset (485:1) at a nominal voltage of 28 Vdc. The power transmission provides a further reduction of 7.2:1 to give an overall gear ratio of nearly 3500:1, assuring reliability of operation at low temperatures. Valve performance (leak rate) data are presented at LN2, LHe, and SfHe temperatures at delivered torques of 18, 27, 31, and 35 N-m. At a closing torque of 31 N-m, a leak rate of 0.028 scc/sec was achieved at 2 K, while at a torque of 18 N-m the leak rate at 300 K was less than 3 x 10 to the -9th scc/sec.

  10. Heimlich valve and pneumothorax.

    PubMed

    Gogakos, Apostolos; Barbetakis, Nikolaos; Lazaridis, George; Papaiwannou, Antonis; Karavergou, Anastasia; Lampaki, Sofia; Baka, Sofia; Mpoukovinas, Ioannis; Karavasilis, Vasilis; Kioumis, Ioannis; Pitsiou, Georgia; Katsikogiannis, Nikolaos; Tsakiridis, Kosmas; Rapti, Aggeliki; Trakada, Georgia; Zissimopoulos, Athanasios; Tsirgogianni, Katerina; Zarogoulidis, Konstantinos; Zarogoulidis, Paul

    2015-03-01

    The Heimlich valve is a small one-way valve used for chest drainage that empties into a flexible collection device and prevents return of gases or fluids into the pleural space. The Heimlich valve is less than 13 cm (5 inches) long and facilitates patient ambulation. Currently there are several systems in the market. It can be used in many patients instead of a traditional water seal drainage system. The Heimlich chest drainage valve was developed so that the process of draining the pleural cavity could be accomplished in a safe, relatively simple, and efficient manner. This valve system has replaced the cumbersome underwater drainage bottle system. Moreover; the Heimlich valve system connects to chest tubing and allows fluid and air to pass in one direction only. This system functions in any position, and it does not ever need to be clamped, a regulated suction can be attached to it if necessary. The valve drains into a plastic bag that can be held at any level, allowing the patient undergoing chest drainage to be ambulatory simply by carrying the bag. In the current mini review we will present the Heimlich valve system and method of insertion.

  11. Mitral valve surgery - open

    MedlinePlus

    ... Saunders; 2012:chap 61. Otto CM, Bonow RO. Valvular heart disease. In: Mann DL, Zipes DP, Libby P, Bonow ... Editorial team. Related MedlinePlus Health Topics Heart Surgery Heart Valve Diseases Mitral Valve Prolapse Browse the Encyclopedia A.D. ...

  12. Minimally invasive valve surgery.

    PubMed

    Woo, Y Joseph

    2009-08-01

    Traditional cardiac valve replacement surgery is being rapidly supplanted by innovative, minimally invasive approaches toward the repair of these valves. Patients are experiencing benefits ranging from less bleeding and pain to faster recovery and greater satisfaction. These operations are proving to be safe, highly effective, and durable, and their use will likely continue to increase and become even more widely applicable.

  13. Linear motion valve

    NASA Technical Reports Server (NTRS)

    Chandler, J. A. (Inventor)

    1985-01-01

    The linear motion valve is described. The valve spool employs magnetically permeable rings, spaced apart axially, which engage a sealing assembly having magnetically permeable pole pieces in magnetic relationship with a magnet. The gap between the ring and the pole pieces is sealed with a ferrofluid. Depletion of the ferrofluid is minimized.

  14. Valve for abrasive material

    DOEpatents

    Gardner, Harold S.

    1982-01-01

    A ball valve assembly for controlling the flow of abrasive particulates including an enlarged section at the bore inlet and an enlarged section at the bore outlet. A refractory ceramic annular deflector is positioned in each of the enlarged sections, substantially extending the useful life of the valve.

  15. Heimlich valve and pneumothorax

    PubMed Central

    Gogakos, Apostolos; Barbetakis, Nikolaos; Lazaridis, George; Papaiwannou, Antonis; Karavergou, Anastasia; Lampaki, Sofia; Baka, Sofia; Mpoukovinas, Ioannis; Karavasilis, Vasilis; Kioumis, Ioannis; Pitsiou, Georgia; Katsikogiannis, Nikolaos; Tsakiridis, Kosmas; Rapti, Aggeliki; Trakada, Georgia; Zissimopoulos, Athanasios; Tsirgogianni, Katerina; Zarogoulidis, Konstantinos

    2015-01-01

    The Heimlich valve is a small one-way valve used for chest drainage that empties into a flexible collection device and prevents return of gases or fluids into the pleural space. The Heimlich valve is less than 13 cm (5 inches) long and facilitates patient ambulation. Currently there are several systems in the market. It can be used in many patients instead of a traditional water seal drainage system. The Heimlich chest drainage valve was developed so that the process of draining the pleural cavity could be accomplished in a safe, relatively simple, and efficient manner. This valve system has replaced the cumbersome underwater drainage bottle system. Moreover; the Heimlich valve system connects to chest tubing and allows fluid and air to pass in one direction only. This system functions in any position, and it does not ever need to be clamped, a regulated suction can be attached to it if necessary. The valve drains into a plastic bag that can be held at any level, allowing the patient undergoing chest drainage to be ambulatory simply by carrying the bag. In the current mini review we will present the Heimlich valve system and method of insertion. PMID:25861609

  16. Space Vehicle Valve System

    NASA Technical Reports Server (NTRS)

    Kelley, Anthony R. (Inventor); Lindner, Jeffrey L. (Inventor)

    2014-01-01

    The present invention is a space vehicle valve system which controls the internal pressure of a space vehicle and the flow rate of purged gases at a given internal pressure and aperture site. A plurality of quasi-unique variable dimension peaked valve structures cover the purge apertures on a space vehicle. Interchangeable sheet guards configured to cover valve apertures on the peaked valve structure contain a pressure-activated surface on the inner surface. Sheet guards move outwardly from the peaked valve structure when in structural contact with a purge gas stream flowing through the apertures on the space vehicle. Changing the properties of the sheet guards changes the response of the sheet guards at a given internal pressure, providing control of the flow rate at a given aperture site.

  17. ULTRA HIGH VACUUM VALVE

    DOEpatents

    Fry, W.A.

    1962-05-29

    A valve for high vacuum applications such as the CStellarator where chamber pressures as low as 2 x 10/sup -10/ mm Hg are necessary is designed with a line-of-sight path through the valve for visual inspection of the contents of reactants in such chambers. The valve comprises a turnable resilient metal ball having an aperture therethrough, means for selectively turning the ball to rotate the axis of its line-of-sight path, and soft, deformable opposing orifices that are movable relatively toward said ball to seal with opposite ball surfaces upon said movement of said axis of said line-of-sight path. The valve also includes a bellows seal connected between said orifices and internal actuating means that eliminates the requirement for gasketed turnable valve closing stems. (AEC)

  18. Boston Scientific Lotus valve.

    PubMed

    Meredith, Ian T; Hood, Kristin L; Haratani, Nicole; Allocco, Dominic J; Dawkins, Keith D

    2012-09-01

    As a result of recent randomised controlled trials and registry observations, transcatheter aortic valve replacement (TAVR) enjoys growing appeal for the treatment of patients at high or extreme risk from surgical aortic valve replacement. However, the current technologies and techniques have important limitations, including risk of stroke, vascular complications and paravalvular aortic regurgitation, which may in turn influence survival. While careful patient selection and screening may improve outcomes, new valve designs and iterations are required. The Lotus aortic valve replacement system is a new fully repositionable device designed to facilitate more precise delivery and minimise paravalvular regurgitation. The safety and efficacy of the Lotus valve are being studied systematically in the REPRISE clinical trial programme.

  19. Intermittent stuck valve after aortic valve replacement with a mechanical valve

    PubMed Central

    Luo, Wenzong; Wang, Xinxin; Li, Jing; Mu, Yun; Ni, Yiming

    2017-01-01

    Abstract Background: Intermittent stuck valve after mechanical valve replacement surgery is a very rare and severe complication. Case summary: We present 1 case of a 53-year-old woman after aortic valve replacement for severe aortic valve stenosis combined with hypertrophy septum. She was diagnosed with intermittent stuck valve only 1 day after surgery by clinical symptoms, intraoperative transoesophageal echocardiogram, and intraoperative findings. Conclusions: Although indications for concomitant myectomy during aortic valve replacement are not clear, we recommend myectomy to prevent stuck valve after St Jude Medical Regent prosthesis replacement for severe aortic valve stenosis combined with hypertrophy septum. PMID:28248877

  20. 40 CFR 60.483-2 - Alternative standards for valves-skip period leak detection and repair.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... valves in gas/vapor and light liquid service. (4) If the percent of valves leaking is greater than 2.0... Industry for which Construction, Reconstruction, or Modification Commenced After January 5, 1981, and on or... periods with the percent of valves leaking equal to or less than 2.0, an owner or operator may begin...

  1. 40 CFR 60.483-2 - Alternative standards for valves-skip period leak detection and repair.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... valves in gas/vapor and light liquid service. (4) If the percent of valves leaking is greater than 2.0... Industry for which Construction, Reconstruction, or Modification Commenced After January 5, 1981, and on or... periods with the percent of valves leaking equal to or less than 2.0, an owner or operator may begin...

  2. 40 CFR 60.483-2 - Alternative standards for valves-skip period leak detection and repair.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... valves in gas/vapor and light liquid service. (4) If the percent of valves leaking is greater than 2.0... Industry for which Construction, Reconstruction, or Modification Commenced After January 5, 1981, and on or... periods with the percent of valves leaking equal to or less than 2.0, an owner or operator may begin...

  3. 40 CFR 60.483-2 - Alternative standards for valves-skip period leak detection and repair.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... valves in gas/vapor and light liquid service. (4) If the percent of valves leaking is greater than 2.0... Industry for which Construction, Reconstruction, or Modification Commenced After January 5, 1981, and on or... periods with the percent of valves leaking equal to or less than 2.0, an owner or operator may begin...

  4. Percutaneous transcatheter aortic valve replacement: first transfemoral implant in Asia.

    PubMed

    Chiam, P T; Koh, T H; Chao, V T; Lee, C Y; See Tho, V Y; Tan, S Y; Lim, S T; Hwang, N C; Sin, Y K; Chua, Y L

    2009-05-01

    Surgical aortic valve replacement (AVR) is the standard of care for patients with symptomatic severe aortic stenosis (AS), providing relief of symptoms and prolonging survival. However, many patients are either denied or not offered surgery due to high surgical risk or non-operability for open AVR. The technology of percutaneous aortic valve implantation emerged in 2002, and has since evolved rapidly with satisfactory results. Currently, almost all the procedures are performed predominantly in Europe and North America. The first-in-Asia percutaneous transcatheter aortic valve implantation via the transfemoral route is described. A 77-year-old man with symptomatic severe AS and at high surgical risk was successfully treated, with sustained clinical improvement and satisfactory haemodynamic results at 30-day follow-up.

  5. Face-Sealing Butterfly Valve

    NASA Technical Reports Server (NTRS)

    Tervo, John N.

    1992-01-01

    Valve plate made to translate as well as rotate. Valve opened and closed by turning shaft and lever. Interactions among lever, spring, valve plate, and face seal cause plate to undergo combination of translation and rotation so valve plate clears seal during parts of opening and closing motions.

  6. Sliding-gate valve

    DOEpatents

    Usnick, George B.; Ward, Gene T.; Blair, Henry O.; Roberts, James W.; Warner, Terry N.

    1979-01-01

    This invention is a novel valve of the slidable-gate type. The valve is designed especially for long-term use with highly abrasive slurries. The sealing surfaces of the gate are shielded by the valve seats when the valve is fully open or closed, and the gate-to-seat clearance is swept with an inflowing purge gas while the gate is in transit. A preferred form of the valve includes an annular valve body containing an annular seat assembly defining a flow channel. The seat assembly comprises a first seat ring which is slidably and sealably mounted in the body, and a second seat ring which is tightly fitted in the body. These rings cooperatively define an annular gap which, together with passages in the valve body, forms a guideway extending normal to the channel. A plate-type gate is mounted for reciprocation in the guideway between positions where a portion of the plate closes the channel and where a circular aperture in the gate is in register with the channel. The valve casing includes opposed chambers which extend outwardly from the body along the axis of the guideway to accommodate the end portions of the gate. The chambers are sealed from atmosphere; when the gate is in transit, purge gas is admitted to the chambers and flows inwardly through the gate-to-seat-ring, clearance, minimizing buildup of process solids therein. A shaft reciprocated by an external actuator extends into one of the sealed chambers through a shaft seal and is coupled to an end of the gate. Means are provided for adjusting the clearance between the first seat ring and the gate while the valve is in service.

  7. Long life valve design concepts

    NASA Technical Reports Server (NTRS)

    Jones, J. R.; Hall, A. H., Jr.

    1975-01-01

    Valve concept evaluation, final candidate selection, design, manufacture, and demonstration testing of a pneumatically actuated 10-inch hybrid poppet butterfly shutoff valve are presented. Conclusions and recommendations regarding those valve characteristics and features which would serve to guide in the formulation of future valve procurements are discussed. The pertinent design goals were temperature range of plus 200 to minus 423 F, valve inlet pressure 35 psia, actuation pressure 750 psia, main seal leakage 3 x 0.00001 sccs at 35 psia valve inlet pressure, and a storage and operating life of 10 years. The valve was designed to be compatible with RP-1, propane, LH2, LO2, He, and N2.

  8. Magnetically driven cold valve for {sup 4}He

    SciTech Connect

    Bueno, J.; Blaauwgeers, R.; Partapsing, R.; Taminiau, I.; Jochemsen, R.

    2006-08-15

    We have designed a low temperature valve for liquid helium, which uses a magnetic field gradient and a permanent magnet to close. For closing, it presses a small ruby ball onto a Torlon seat. We present a small valve that is easy to build and easily controlled via two wires. It has a fast response, reliable, and has the advantage that there is no dead volume change on closing and no additional helium line is required to operate.

  9. Quartz ball valve

    NASA Technical Reports Server (NTRS)

    Goetz, C.; Ingle, W. M. (Inventor)

    1980-01-01

    A ball valve particularly suited for use in the handling of highly corrosive fluids is described. It is characterized by a valve housing formed of communicating segments of quartz tubing, a pair of communicating sockets disposed in coaxial alignment with selected segments of tubing for establishing a pair of inlet ports communicating with a common outlet port, a ball formed of quartz material supported for displacement between the sockets and configured to be received alternately thereby, and a valve actuator including a rod attached to the ball for selectively displacing the ball relative to each of the sockets for controlling fluid flow through the inlet ports.

  10. Mesofluidic two stage digital valve

    DOEpatents

    Jansen, John F; Love, Lonnie J; Lind, Randall F; Richardson, Bradley S

    2013-12-31

    A mesofluidic scale digital valve system includes a first mesofluidic scale valve having a valve body including a bore, wherein the valve body is configured to cooperate with a solenoid disposed substantially adjacent to the valve body to translate a poppet carried within the bore. The mesofluidic scale digital valve system also includes a second mesofluidic scale valve disposed substantially perpendicular to the first mesofluidic scale valve. The mesofluidic scale digital valve system further includes a control element in communication with the solenoid, wherein the control element is configured to maintain the solenoid in an energized state for a fixed period of time to provide a desired flow rate through an orifice of the second mesofluidic valve.

  11. Mitral Valve Prolapse

    MedlinePlus

    ... Kawasaki Disease Long Q-T Syndrome Marfan Syndrome Metabolic Syndrome Mitral Valve Prolapse Myocardial Bridge Myocarditis Obstructive Sleep Apnea Pericarditis Peripheral Vascular Disease Rheumatic Fever Sick Sinus Syndrome Silent Ischemia Stroke Sudden ...

  12. Pulmonary valve stenosis

    MedlinePlus

    ... valvuloplasty - pulmonary Images Heart valves References Carabello BA. Valvular heart disease. In: Goldman L, Schafer AI, eds. Goldman's Cecil ... Saunders; 2016:chap 69. Otto CM, Bownow RO. Valvular heart disease. In: Mann DL, Zipes DP, Libby P, Bonow ...

  13. Valve Repair or Replacement

    MedlinePlus

    ... invasive valve surgery can be done using a robot. Robotic surgery does not require a large incision ... the procedure. The Texas Heart Institute has a robot. With robotic surgery, the surgeon has a control ...

  14. Mitral Valve Prolapse.

    ERIC Educational Resources Information Center

    Bergy, Gordon G.

    1980-01-01

    Mitral valve prolapse is the most common heart disease seen in college and university health services. It underlies most arrhythmia and many chest complaints. Activity and exercise restrictions are usually unnecessary. (Author/CJ)

  15. Pulmonary Valve Stenosis

    MedlinePlus

    ... as mild, moderate or severe, depending on a measurement of the blood pressure difference between the right ... balloon, widening the narrowed valve to increase blood flow, and then removes the balloon. The most common ...

  16. Bidirectional piston valve

    DOEpatents

    Fischer, Harry C.

    1977-01-01

    This invention is a reversing valve having an inlet, an outlet, and an inlet-outlet port. The valve is designed to respond to the introduction of relatively high-pressure fluid at its inlet or, alternatively, of lower-pressure fluid at its inlet-outlet port. The valve includes an axially slidable assembly which is spring-biased to a position where it isolates the inlet and connects the inlet-outlet port to the outlet. The admission of high-pressure fluid to the inlet displaces the slidable assembly to a position where the outlet is isolated and the inlet is connected to the inlet-outlet port. The valve is designed to minimize pressure drops and leakage. It is of a reliable and comparatively simple design.

  17. Bicuspid aortic valve

    MedlinePlus

    ... stiff and not open up. This is called aortic stenosis , which causes the heart to pump harder than usual to get blood through the valve. The aorta may become enlarged with this condition. BAV is ...

  18. THERMALLY OPERATED VAPOR VALVE

    DOEpatents

    Dorward, J.G. Jr.

    1959-02-10

    A valve is presented for use in a calutron to supply and control the vapor to be ionized. The invention provides a means readily operable from the exterior of the vacuum tank of the apparatuss without mechanical transmission of forces for the quick and accurate control of the ionizing arc by a corresponding control of gas flow theretos thereby producing an effective way of carefully regulating the operation of the calutron. The invention consists essentially of a tube member extending into the charge bottle of a calutron devices having a poppet type valve closing the lower end of the tube. An electrical heating means is provided in the valve stem to thermally vary the length of the stem to regulate the valve opening to control the flow of material from the charge bottle.

  19. Valve for gas centrifuges

    DOEpatents

    Hahs, Charles A.; Burbage, Charles H.

    1984-01-01

    The invention is a pneumatically operated valve assembly for simultaneously (1) closing gas-transfer lines connected to a gas centrifuge or the like and (2) establishing a recycle path between two of the lines so closed. The valve assembly is especially designed to be compact, fast-acting, reliable, and comparatively inexpensive. It provides large reductions in capital costs for gas-centrifuge cascades.

  20. Bicuspid Aortic Valve

    DTIC Science & Technology

    2006-08-01

    severe aortic stenosis . Figure 1F. Oblique axial cine bright blood imaging through the valve plane of the aorta, demonstrates the aortic valve to...the ascending aorta. This moderate to large jet is consistent with moderate to severe aortic stenosis . No diastolic jet to suggest aortic ...conditions. Functional impairment of the aortic valve—namely aortic stenosis and aortic regurgitation—is the most common complication (in up to 68-85% of

  1. Piston and valve assembly

    SciTech Connect

    Rolder, G. K.

    1985-10-01

    A downhole hydraulically actuated pump assembly of either the free or fixed type lifts formation fluid from the bottom of a borehole to the surface of the ground. The downhole pump has a power piston which actuates a production plunger. A valve means is concentrically arranged within the power piston. A stationary, hollow valve control rod extends through the power piston and through the valve means, with a lower marginal end of the control rod terminating within the production plunger. Power fluid flows through the control rod and to the valve means. As the power piston reciprocates within the engine cylinder, means on the control rod actuates the valve means between two alternant positions so that power fluid is applied to the bottom face of the power piston to thereby cause the power piston to reciprocate upward; and thereafter, the control rod causes the valve means to shift to the other position, whereupon spent power fluid is exhausted from the engine cylinder. The spent power fluid is admixed with production fluid and is conducted to the surface of the ground.

  2. Engine valve train module

    SciTech Connect

    Wirth, R.C.; De Klep, E.L.

    1988-01-26

    In a reciprocating internal combustion engine of the type having an engine block means defining at least one cylinder with a first port and a second port in flow communication therewith, a first valve and a second valve reciprocably located to control flow through the first and second ports, respectively, and normally biased to a port closed position, the improvement is described comprising a valve train module that includes a housing adapted to be secured by machine screws to the engine block means above the first and second valves; an engine driven camshaft having axial spaced apart first and second cam lobes operatively supported for rotation in the housing; a lifter guide bore in the housing located substantially coaxial with the reciprocating axis of the first valve; a direct acting hydraulic lash adjuster operatively supported in the lifter guide bore with one end thereof engaging the first cam lobe and at its opposite end being operatively connected to the first valve. A follower guide bore is in the housing operatively aligned relative to the second cam lobe; a hollow rocker shaft is operatively fixed in the housing in parallel spaced apart relationship to the engine driven camshaft; a rocker arm pivotably supported intermediate its ends by the rocker shaft.

  3. Mitral disc-valve variance

    PubMed Central

    Berroya, Renato B.; Escano, Fernando B.

    1972-01-01

    This report deals with a rare complication of disc-valve prosthesis in the mitral area. A significant disc poppet and struts destruction of mitral Beall valve prostheses occurred 20 and 17 months after implantation. The resulting valve incompetence in the first case contributed to the death of the patient. The durability of Teflon prosthetic valves appears to be in question and this type of valve probably will be unacceptable if there is an increasing number of disc-valve variance in the future. Images PMID:5017573

  4. LIQUID TARGET

    DOEpatents

    Martin, M.D.; Salsig, W.W. Jr.

    1959-01-13

    A liquid handling apparatus is presented for a liquid material which is to be irradiated. The apparatus consists essentially of a reservoir for the liquid, a target element, a drain tank and a drain lock chamber. The target is in the form of a looped tube, the upper end of which is adapted to be disposed in a beam of atomic particles. The lower end of the target tube is in communication with the liquid in the reservoir and a means is provided to continuously circulate the liquid material to be irradiated through the target tube. Means to heat the reservoir tank is provided in the event that a metal is to be used as the target material. The apparatus is provided with suitable valves and shielding to provide maximum safety in operation.

  5. 9. BUTTERFLY VALVE CONTROL DIABLO POWERHOUSE. BUTTERFLY VALVES WERE MANUFACTURED ...

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

    9. BUTTERFLY VALVE CONTROL DIABLO POWERHOUSE. BUTTERFLY VALVES WERE MANUFACTURED BY THE PELTON WATER WHEEL COMPANY IN 1931, 1989. - Skagit Power Development, Diablo Powerhouse, On Skagit River, 6.1 miles upstream from Newhalem, Newhalem, Whatcom County, WA

  6. Implantation of the CoreValve percutaneous aortic valve.

    PubMed

    Lamarche, Yoan; Cartier, Raymond; Denault, André Y; Basmadjian, Arsène; Berry, Colin; Laborde, Jean-Claude; Bonan, Raoul

    2007-01-01

    Surgical aortic valve replacement is the only recommended treatment for significant aortic valve stenosis. Percutaneous aortic valve replacement appears to be a novel option for high-risk patients. We report the implantation of the ReValving system (CoreValve, Paris, France) in a 64-year-old woman who was refused aortic valve replacement surgery for critical aortic stenosis and left ventricular dysfunction because of severe pulmonary fibrosis. After anesthesia, the patient was put on femorofemoral cardiopulmonary bypass, and underwent a balloon valvuloplasty with subsequent retrograde aortic valve replacement by the ReValving system. Transesophageal echocardiographic monitoring of the patient's hemodynamics showed immediate improvements of the valvular area and left ventricular ejection fraction and only traces of paravalvular leaks. The patient was easily weaned from ventilation and resumed activity soon after the surgery. A multidisciplinary approach is presently necessary to offer a reliable and safe procedure.

  7. Perceval Sutureless Valve – are Sutureless Valves Here?

    PubMed Central

    Chandola, Rahul; Teoh, Kevin; Elhenawy, Abdelsalam; Christakis, George

    2015-01-01

    With the advent of transcatheter aortic valve implantation (TAVI) techniques, a renewed interest has developed in sutureless aortic valve concepts in the last decade. The main feature of sutureless aortic valve implantation is the speed of insertion, thus making implantation easier for the surgeon. As a result, cross clamp times and myocardial ischemia may be reduced. The combined procedures (CABG with AVR in particular) can be done with a short cross clamp time. Perceval valve also provides an increased effective orifice area as compared with a stented bioprosthesis. Sutureless implantation of the Perceval valve is not only associated with shorter cross-clamp and cardiopulmonary bypass times but improved clinical outcomes too. This review covers the sutureless aortic valves and their evolution, with elaborate details on Perceval S valve in particular (which is the most widely used sutureless valve around the globe). PMID:25394851

  8. 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.

  9. Fast closing valve

    SciTech Connect

    Hanson, C.L.

    1984-01-10

    A valve is provided for protecting the high vacuum of a particle accelerator in the event of air leakage, wherein the valve provides an axially symmetrical passage to avoid disturbance of the partical beam during normal operation, and yet enables very rapid and tight closure of the beam-carrying pipe in the event of air leakage. The valve includes a ball member which can rotate between a first position wherein a bore in the member is aligned with the beam pipe, and a second position out of line with the pipe. A seal member is flexibly sealed to the pipe, and has a seal end which can move tightly against the ball member after the bore has rotated out of line with the pipe, to thereby assure that the seal member does not retard rapid rotation of the ball valve member. The ball valve member can be rapidly rotated by a conductive arm fixed to it and which is rotated by the discharge of a capacitor bank through coils located adjacent to the arm.

  10. Fast closing valve

    DOEpatents

    Hanson, Clark L.

    1984-01-10

    A valve is provided for protecting the high vacuum of a particle accelera in the event of air leakage, wherein the valve provides an axially symmetrical passage to avoid disturbance of the partical beam during normal operation, and yet enables very rapid and tight closure of the beam-carrying pipe in the event of air leakage. The valve includes a ball member (30) which can rotate between a first position wherein a bore (32) in the member is aligned with the beam pipe, and a second position out of line with the pipe. A seal member (38) is flexibly sealed to the pipe, and has a seal end which can move tightly against the ball member after the bore has rotated out of line with the pipe, to thereby assure that the seal member does not retard rapid rotation of the ball valve member. The ball valve member can be rapidly rotated by a conductive arm (40) fixed to it and which is rotated by the discharge of a capacitor bank through coils (44, 45) located adjacent to the arm.

  11. Sutureless aortic valve replacement

    PubMed Central

    Phan, Kevin

    2015-01-01

    The increasing incidence of aortic stenosis and greater co-morbidities and risk profiles of the contemporary patient population has driven the development of minimally invasive aortic valve surgery and percutaneous transcatheter aortic valve implantation (TAVI) techniques to reduce surgical trauma. Recent technological developments have led to an alternative minimally invasive option which avoids the placement and tying of sutures, known as “sutureless” or rapid deployment aortic valves. Potential advantages for sutureless aortic prostheses include reducing cross-clamp and cardiopulmonary bypass (CPB) duration, facilitating minimally invasive surgery and complex cardiac interventions, whilst maintaining satisfactory hemodynamic outcomes and low paravalvular leak rates. However, given its recent developments, the majority of evidence regarding sutureless aortic valve replacement (SU-AVR) is limited to observational studies and there is a paucity of adequately-powered randomized studies. Recently, the International Valvular Surgery Study Group (IVSSG) has formulated to conduct the Sutureless Projects, set to be the largest international collaborative group to investigate this technology. This keynote lecture will overview the use, the potential advantages, the caveats, and current evidence of sutureless and rapid deployment aortic valve replacement (AVR). PMID:25870807

  12. Valving for controlling a fluid-driven reciprocating apparatus

    SciTech Connect

    Whitehead, J.C.

    1995-06-27

    A pair of control valve assemblies is described for alternately actuating a pair of fluid-driven free-piston devices by using fluid pressure communication therebetween. Each control valve assembly is switched by a pressure signal depending on the state of its counterpart`s piston. The communication logic is arranged to provide overlap of the forward strokes of the pistons, so that at least one of the pair will always be pressurized. Thus, uninterrupted pumping of liquid is made possible from a pair of free-piston pumps. In addition, the speed and frequency of piston stroking is entirely dependent on the mechanical power load applied. In the case of a pair of pumps, this enables liquid delivery at a substantially constant pressure over the full range of flow rates, from zero to maximum flow. Each of the valve assemblies uses an intake-exhaust valve and a signal valve with the signal valve of one pump being connected to be pressure responsive to the piston of the opposite cylinder or pump. 15 figs.

  13. Valving for controlling a fluid-driven reciprocating apparatus

    SciTech Connect

    Whitehead, John C.

    1995-01-01

    A pair of control valve assemblies for alternately actuating a pair of fluid-driven free-piston devices by using fluid pressure communication therebetween. Each control valve assembly is switched by a pressure signal depending on the state of its counterpart's piston. The communication logic is arranged to provide overlap of the forward strokes of the pistons, so that at least one of the pair will always be pressurized. Thus, uninterrupted pumping of liquid is made possible from a pair of free-piston pumps. In addition, the speed and frequency of piston stroking is entirely dependent on the mechanical power load applied. In the case of a pair of pumps, this enables liquid delivery at a substantially constant pressure over the full range of flow rates, from zero to maximum flow. Each of the valve assemblies uses an intake-exhaust valve and a signal valve with the signal valve of one pump being connected to be pressure responsive to the piston of the opposite cylinder or pump.

  14. Aortic valve replacement with the De Bakey valve.

    PubMed

    Paton, B C; Pine, M B

    1976-10-01

    De Bakey prostheses were inserted in 29 patients with aortic valve disease between October, 1970, and May, 1972. Ten patients have died, but all but one of the remaining 19 have beel followed for a minimum of 19 months. Evaluation of the results in these subjects indicates that the function of the De Bakey valve compares favorably with that of other aortic valve prostheses.

  15. 81. View of 41 valve house (right) and 42 valve ...

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

    81. View of 4-1 valve house (right) and 4-2 valve house (left); in the foreground is penstock which extends from Penstock No. 1 to the 4-1 valve house; looking south. Photo by Jet Lowe, HAER, 1989. - Puget Sound Power & Light Company, White River Hydroelectric Project, 600 North River Avenue, Dieringer, Pierce County, WA

  16. 83. Interior of 42 valve house; the motor and valve ...

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

    83. Interior of 4-2 valve house; the motor and valve mechanism is identical to that in the 4-1 valve house. Photo by Jet Lowe, HAER, 1989. - Puget Sound Power & Light Company, White River Hydroelectric Project, 600 North River Avenue, Dieringer, Pierce County, WA

  17. Development of a Cryogenic Gate Valve with Robust Sealing

    NASA Astrophysics Data System (ADS)

    Hatfield, W. H.; Sass, J. P.

    2008-03-01

    A soft-seal cryogenic gate valve has been designed, fabricated, and demonstrated by the Cryogenics Test Laboratory (CTL) at the Kennedy Space Center (KSC), featuring a robust sealing technology and a high flow coefficient (Cv). The robust seal design incorporates novel retracting seal-retaining disks to prevent soft-seal abrasive wear and damage from the valve body hard seat. Advanced materials were incorporated into the design, including fluorinated ethylene propylene (FEP) standard seal material and porous sponge polytetrafluoroethylene (PTFE) optional seal material. Titanium nitride coating was applied to the 316 stainless-steel surfaces that are subject to wearing or galling. The valve is suitable for applications from ambient temperature down to liquid nitrogen temperature (77 K), with a seat leakage rate of less than 1 standard-cubic-centimeter-per minute (sccm) per inch of valve diameter. The very low seat leakage, throttling capability, and high flow coefficient (Cv) of the valve make it suitable for block valve applications on standard to very large cryogenic storage tanks or other applications requiring highly reliable full flow cryogenic valves.

  18. 46 CFR 154.532 - Valves: Cargo tank MARVS greater than 69 kPa gauge (10 psig).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Valves: Cargo tank MARVS greater than 69 kPa gauge (10... greater than 69 kPa gauge (10 psig). (a) Except connections for tank safety relief valves and except for... on a cargo tank with a MARVS greater than 69 kPa gauge (10 psig) must have, as close to the tank...

  19. What Is Mitral Valve Prolapse?

    MedlinePlus

    ... may not close tightly. These flaps normally help seal or open the valve. Much of the time, ... and tricuspid valves close. They form a tight seal that prevents blood from flowing back into the ...

  20. Medications for Heart Valve Symptoms

    MedlinePlus

    ... Peripheral Artery Disease Venous Thromboembolism Aortic Aneurysm More Medications for Heart Valve Symptoms Updated:Sep 21,2016 How do medications help people with valve problems? People who are ...

  1. Locking apparatus for gate valves

    DOEpatents

    Fabyan, Joseph; Williams, Carl W.

    1988-01-01

    A locking apparatus for fluid operated valves having a piston connected to the valve actuator which moves in response to applied pressure within a cylinder housing having a cylinder head, a catch block is secured to the piston, and the cylinder head incorporates a catch pin. Pressure applied to the cylinder to open the valve moves the piston adjacent to the cylinder head where the catch pin automatically engages the catch block preventing futher movement of the piston or premature closure of the valve. Application of pressure to the cylinder to close the valve, retracts the catch pin, allowing the valve to close. Included are one or more selector valves, for selecting pressure application to other apparatus depending on the gate valve position, open or closed, protecting such apparatus from damage due to premature closing caused by pressure loss or operational error.

  2. Locking apparatus for gate valves

    DOEpatents

    Fabyan, J.; Williams, C.W.

    A locking apparatus for fluid operated valves having a piston connected to the valve actuator which moves in response to applied pressure within a cylinder housing having a cylinder head, a catch block is secured to the piston, and the cylinder head incorporates a catch pin. Pressure applied to the cylinder to open the valve moves the piston adjacent to the cylinder head where the catch pin automatically engages the catch block preventing further movement of the piston or premature closure of the valve. Application of pressure to the cylinder to close the valve, retracts the catch pin, allowing the valve to close. Included are one or more selector valves, for selecting pressure application to other apparatus depending on the gate valve position, open or closed, protecting such apparatus from damage due to premature closing caused by pressure loss or operational error.

  3. Aortic valve surgery - minimally invasive

    MedlinePlus

    ... of the heart is reduced. This is called aortic stenosis. The aortic valve can be replaced using: Minimally ... RN, Wang A. Percutaneous heart valve replacement for aortic stenosis: state of the evidence. Ann Intern Med . 2010; ...

  4. Valve-spring Surge

    NASA Technical Reports Server (NTRS)

    Marti, Willy

    1937-01-01

    Test equipment is described that includes a system of three quartz indicators whereby three different pressures could be synchronized and simultaneously recorded on a single oscillogram. This equipment was used to test the reliction of waves at ends of valve spring, the dynamical stress of the valve spring for a single lift of the valve, and measurement of the curve of the cam tested. Other tests included simultaneous recording of the stress at both ends of the spring, spring oscillation during a single lift as a function of speed, computation of amplitude of oscillation for a single lift by harmonic analysis, effect of cam profile, the setting up of resonance, and forced spring oscillation with damping.

  5. Sliding valve pump

    SciTech Connect

    Rupert, C.L.

    1980-09-09

    A sliding valve pump for oil wells which includes a working barrel having a plurality of apertures located in spaced relationship in the wall thereof and a pair of travelling valves fitted within the working barrel and carried by a plunger rod, the valves also having a plurality of apertures or ports for periodic registration with the ports in the working barrel wall to facilitate pumping of fluid from an oil reservoir or pool to the surface. The pump is designed to pull the oil-gas mixture from the reservoir pool into the lower section of the working barrel on the downward stroke, and to subsequently pump the collected oil through the barrel and tubing upwardly toward the surface on the upward stroke.

  6. Variable Valve Actuation

    SciTech Connect

    Jeffrey Gutterman; A. J. Lasley

    2008-08-31

    Many approaches exist to enable advanced mode, low temperature combustion systems for diesel engines - such as premixed charge compression ignition (PCCI), Homogeneous Charge Compression Ignition (HCCI) or other HCCI-like combustion modes. The fuel properties and the quantity, distribution and temperature profile of air, fuel and residual fraction in the cylinder can have a marked effect on the heat release rate and combustion phasing. Figure 1 shows that a systems approach is required for HCCI-like combustion. While the exact requirements remain unclear (and will vary depending on fuel, engine size and application), some form of substantially variable valve actuation is a likely element in such a system. Variable valve actuation, for both intake and exhaust valve events, is a potent tool for controlling the parameters that are critical to HCCI-like combustion and expanding its operational range. Additionally, VVA can be used to optimize the combustion process as well as exhaust temperatures and impact the after treatment system requirements and its associated cost. Delphi Corporation has major manufacturing and product development and applied R&D expertise in the valve train area. Historical R&D experience includes the development of fully variable electro-hydraulic valve train on research engines as well as several generations of mechanical VVA for gasoline systems. This experience has enabled us to evaluate various implementations and determine the strengths and weaknesses of each. While a fully variable electro-hydraulic valve train system might be the 'ideal' solution technically for maximum flexibility in the timing and control of the valve events, its complexity, associated costs, and high power consumption make its implementation on low cost high volume applications unlikely. Conversely, a simple mechanical system might be a low cost solution but not deliver the flexibility required for HCCI operation. After modeling more than 200 variations of the

  7. Magnetostrictive valve assembly

    NASA Technical Reports Server (NTRS)

    Richard, James A. (Inventor)

    2008-01-01

    A magnetostrictive valve assembly includes a housing that defines a passage with a seat being formed therein. A magnetically-biased and axially-compressed magnetostrictive assembly slidingly fitted in the passage is configured as a hollow and open-ended conduit adapted to support a flow of a fluid therethrough. Current-carrying coil(s) disposed about the passage in the region of the magnetostrictive assembly generate a magnetic field in the passage when current flows through the coil(s). A hollow valve body with side ports is coupled on one end thereof to an axial end of the magnetostrictive assembly. The other end of the valve body is designed to seal with the seat formed in the housing's passage when brought into contact therewith.

  8. Josephson magnetic rotary valve

    SciTech Connect

    Soloviev, I. I.; Klenov, N. V.; Bakurskiy, S. V.; Bol'ginov, V. V.; Ryazanov, V. V.; Kupriyanov, M. Yu.; Golubov, A. A.

    2014-12-15

    We propose a control element for a Josephson spin valve. It is a complex Josephson device containing ferromagnetic (F) layer in the weak-link area consisting of two regions, representing 0 and π Josephson junctions, respectively. The valve's state is defined by mutual orientations of the F-layer magnetization vector and boundary line between 0 and π sections of the device. We consider possible implementation of the control element by introduction of a thin normal metal layer in a part of the device area. By means of theoretical simulations, we study properties of the valve's structure as well as its operation, revealing such advantages as simplicity of control, high characteristic frequency, and good legibility of the basic states.

  9. Asthma - quick-relief drugs

    MedlinePlus

    ... About MedlinePlus Site Map FAQs Customer Support Health Topics Drugs & Supplements Videos & Tools Español You Are Here: Home → Medical Encyclopedia → Asthma - quick-relief drugs URL of this page: //medlineplus.gov/ency/patientinstructions/000008.htm Asthma - quick- ...

  10. Team Approach to Pain Relief

    MedlinePlus

    ... barely functional. A consultation with the Pain and Palliative Care Service produced a medication plan that eased her pain without interfering with her quality of life, and acupuncture brought relief from severe shoulder pain. "I'm functional again. That's the ...

  11. Self-regulating valve

    DOEpatents

    Humphreys, D.A.

    1982-07-20

    A variable, self-regulating valve having a hydraulic loss coefficient proportional to a positive exponential power of the flow rate. The device includes two objects in a flow channel and structure which assures that the distance between the two objects is an increasing function of the flow rate. The range of spacing between the objects is such that the hydraulic resistance of the valve is an increasing function of the distance between the two objects so that the desired hydraulic loss coefficient as a function of flow rate is obtained without variation in the flow area.

  12. Ball valve safety screen

    SciTech Connect

    Bolding, B.H.

    1981-09-01

    A device for preventing unwanted objects from entering the ball assembly of a float collar or float shoe and otherwise damaging or plugging the valve mechanism therein is disclosed. The device comprises a screen constructed of expanded metal and rigidly affixed to the interior of the float collar or float shoe above the ball valve assembly. The screen portion is either mounted to the interior surface of the float collar sleeve by an annular structural member or mounted to a structural band which is partially embedded in the concrete portion of the float collar or casing guide shoe.

  13. Lightweight Valve Closes Duct Quickly

    NASA Technical Reports Server (NTRS)

    Fournier, Walter L.; Burgy, N. Frank

    1991-01-01

    Expanding balloon serves as lightweight emergency valve to close wide duct. Uninflated balloon stored in housing of duct. Pad resting on burst diaphragm protects balloon from hot gases in duct. Once control system triggers valve, balloon inflates rapidly to block duct. Weighs much less than does conventional butterfly, hot-gas, or poppet valve capable of closing duct of equal diameter.

  14. Lipomatous hamartoma of mitral valve.

    PubMed

    Bhat, Seetharama P S; Gowda, Girish S L; Chikkatur, Raghavendra; Nanjappa, Manjunath C

    2016-01-01

    Primary cardiac tumors are very rare, and tumors arising from cardiac valves are extremely rare. We present a case of lipomatous hamartoma of the mitral valve in a young female. This is the 6th case of lipomatous hamartoma of the mitral valve to be reported. We discuss the operative and histopathological findings.

  15. Valve stem and packing assembly

    DOEpatents

    Wordin, John J.

    1991-01-01

    A valve stem and packing assembly is provided in which a rotatable valve stem includes a first tractrix surface for sliding contact with a stem packing and also includes a second tractrix surface for sliding contact with a bonnet. Force is applied by means of a spring, gland flange, and gland on the stem packing so the stem packing seals to the valve stem and bonnet. This configuration serves to create and maintain a reliable seal between the stem packing and the valve stem. The bonnet includes a second complementary tractrix surface for contacting the second sliding tractrix surface, the combination serving as a journal bearing for the entire valve stem and packing assembly. The journal bearing so configured is known as a Schiele's pivot. The Schiele's pivot also serves to maintain proper alignment of the valve stem with respect to the bonnet. Vertical wear between the surfaces of the Schiele's pivot is uniform at all points of contact between the second sliding tractrix surface and the second complementary tractrix surface of a bonnet. The valve stem is connected to a valve plug by means of a slip joint. The valve is opened and closed by rotating the valve stem. The slip joint compensates for wear on the Schiele's pivot and on the valve plug. A ledge is provided on the valve bonnet for the retaining nut to bear against. The ledge prevents overtightening of the retaining nut and the resulting excessive friction between stem and stem packing.

  16. Valve stem and packing assembly

    DOEpatents

    Wordin, J.J.

    1991-09-03

    A valve stem and packing assembly is provided in which a rotatable valve stem includes a first tractrix surface for sliding contact with a stem packing and also includes a second tractrix surface for sliding contact with a bonnet. Force is applied by means of a spring, gland flange, and gland on the stem packing so the stem packing seals to the valve stem and bonnet. This configuration serves to create and maintain a reliable seal between the stem packing and the valve stem. The bonnet includes a second complementary tractrix surface for contacting the second sliding tractrix surface, the combination serving as a journal bearing for the entire valve stem and packing assembly. The journal bearing so configured is known as a Schiele's pivot. The Schiele's pivot also serves to maintain proper alignment of the valve stem with respect to the bonnet. Vertical wear between the surfaces of the Schiele's pivot is uniform at all points of contact between the second sliding tractrix surface and the second complementary tractrix surface of a bonnet. The valve stem is connected to a valve plug by means of a slip joint. The valve is opened and closed by rotating the valve stem. The slip joint compensates for wear on the Schiele's pivot and on the valve plug. A ledge is provided on the valve bonnet for the retaining nut to bear against. The ledge prevents over tightening of the retaining nut and the resulting excessive friction between stem and stem packing. 2 figures.

  17. Transcatheter Valve-in-Valve: A Cautionary Tale.

    PubMed

    Luc, Jessica G Y; Shanks, Miriam; Tyrrell, Benjamin D; Welsh, Robert C; Butler, Craig R; Meyer, Steven R

    2016-09-01

    Transcatheter aortic valve replacement (TAVR) by valve-in-valve (VIV) implantation is an alternative treatment for high-risk patients with a degenerating aortic bioprosthesis. We present a case of transapical TAVR VIV with a 29-mm Edwards SAPIEN XT (ESV) (Edwards Lifesciences, Irvine, CA) into a 29-mm Medtronic Freestyle stentless bioprosthesis (Medtronic Inc, Minneapolis, MN) in which unanticipated dilatation of the Freestyle bioprosthesis resulted in intraprocedural embolization of the TAVR valve, necessitating urgent conversion to a conventional surgical aortic valve replacement (AVR). Our experience suggests that TAVR VIV with the 29-mm ESV in the setting of a degenerated 29-mm Freestyle stentless bioprosthesis must be undertaken with caution.

  18. Automatic liquid inventory collecting and dispensing unit

    NASA Technical Reports Server (NTRS)

    Hall, J. B., Jr.; Williams, E. F. (Inventor)

    1975-01-01

    A means is provided for automatically collecting waste liquids and for simultaneously feeding these liquids into water recovery processes. The invention includes first and second tanks with first and second two-way solenoid valves associated with each of the tanks. The first solenoid valve is connected to the liquid source and its associated tank so as to allow liquid to flow into the tank when the valve is in its normal position and to allow the liquid to flow out of the tank when the valve is in its actuated position. The second valve is connected to its associated tank and a gas supply so as to allow gas inside the tank to flow out when the valve is in its normal position and to allow gas to flow from the gas supply into the tank when the valve is in its actuated position. Control circuits are included for actuating the two valves associated with the first tank and not actuating the valves associated with the second tank. The first tank is filled and the second tank is emptied.

  19. 32 CFR 516.19 - Injunctive relief.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY AID OF CIVIL AUTHORITIES AND PUBLIC RELATIONS LITIGATION Reporting Legal Proceedings to HQDA § 516.19 Injunctive relief. (a) General. Plaintiffs... relief is granted. (4) The public interest....

  20. The Liquid Metal Plasma Valve Closing Switch,

    DTIC Science & Technology

    1976-01-01

    Table 1. Switch Specification s Closing HVDC LMPV Switch Converter LMPV Circuit Parameter...Parameters Rating Breaker Rating Peak Voltage 50-200 kV 150 kV nominal 30 kV Pulse Width 20-50 1isec 6 msec 20 msec Peak Current 8-4 kA 1.8 kA nominal