1、Designation:F179500(Reapproved 2013)An American National StandardStandard Specification forPressure-Reducing Valves for Air or Nitrogen Systems1This standard is issued under the fixed designation F1795;the number immediately following the designation indicates the year oforiginal adoption or,in the
2、case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This specification covers the design,construction,testing,and operating requirements for self-
3、contained pressure-reducing valves for air or nitrogen systems.1.2 The values stated in this specification in inch-poundsunits are to be regarded as the standard.The SI equivalentshown in parentheses are provided for information only.2.Referenced Documents2.1 ASTM Standards:2F992 Specification for V
4、alve Label PlatesF1685 Specification for Pressure-Reducing Manifolds forAir or Nitrogen Systems2.2 American National Standards Institute(ANSI):B1.1 United Screw Threads(UN and UNR Thread Form)3B1.20.1 Pipe Threads,General Purpose(Inch)3B16.11 ForgedSteelFittings,Socket-WeldingandThreaded3B16.25 Butt
5、welding Ends3B16.34 ValvesFlanged,Threaded,and Welded End32.3 Military Standards and Specifications:MIL-STD-167-1 Mechanical Vibrations of ShipboardEquipment(Type IEnvironmental and Type IIInternally Excited)4MIL-STD-740-1 Airborne Sound Measurements andAccep-tance Criteria of Shipboard Equipment4MI
6、L-S-901 Shock Tests,H.I.(High-Impact);ShipboardMachinery,Equipment and Systems,Requirements for4MIL-F-1183 Fittings,Pipe,Cast Bronze,Silver-Brazing,General Specifications for42.4 Government Drawings:Naval Sea Systems Command(NAVSEA):NAVSEA 803-1385884 Unions,Fittings and Adapters Buttand Socket Weld
7、ing 6000 PSI,WOG,NPSNAVSEA 803-1385943 Unions,Silver Brazing 3000 PSI,WOG,NPS,for UT InspectionNAVSEA 803-1385946 Unions,Bronze Silver Brazing,WOG for UT Inspection3.Terminology3.1 Definitions:3.1.1 accuracy of regulationthe amount by which thedownstream pressure may vary when the pressure-reducingv
8、alve is set at any pressure within the required set pressurerange and is subjected to any combination of inlet pressure,flow demand,and ambient temperature variations within thespecified limits.3.1.2 bubble-sightno visible leakage over a 3-min periodusing either water submersion or the application o
9、f bubble fluidfor detection.3.1.3 external leakageleakage from the pressure-reducingvalve which escapes to atmosphere.3.1.4 fail-open flow capacitythe ability of the pressure-reducing valve to pass flow under any given set of pressureconditions when,as a result of mechanical failure,it hasassumed a
10、position of least resistance to flow.3.1.5 flow capacitythe ability of the pressure-reducingvalve to pass flow under any given set of pressure conditions.3.1.6 flow rate demandthe amount of flow demanded bythe system at any given time downstream of the pressure-reducing valve.3.1.7 flow rate demand
11、rangethe range over which theflow demand can vary.3.1.8 hydrostatic shell test pressure(s)The hydrostatic testpressures that the inlet and outlet of the pressure-reducingvalve is required to withstand without damage.Pressure-reducing valve operation is not required during application ofshell test pr
12、essure,but the pressure-reducing valve must meetall performance requirements after the shell test pressure hasbeen removed.3.1.9 inlet operating pressure rangethe range over whichthe inlet pressure supplied to the pressure-reducing valve can1This specification is under the jurisdiction of ASTM Commi
13、ttee F25 on Shipsand Marine Technology and is the direct responsibility of Subcommittee F25.11 onMachinery and Piping Systems.Current edition approved May 1,2013.Published May 2013.Originallyapproved in 1997.Last previous edition approved in 2006 as F1795 00(2006).DOI:10.1520/F1795-00R13.2For refere
14、nced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute(ANSI),25 W.43rd St.,4th
15、 Floor,New York,NY 10036.4Available from Standardization Documents Order Desk,Bldg.4 Section D,700Robbins Ave.,Philadelphia,PA 191115094,Attn:NPODS.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 vary under any operational conditions whic
16、h the pressure-reducing valve can be subjected to in service.3.1.10 operating pressure(s)the pressures within thepressure-reducing valve during service.3.1.11 pressure ratingsthe pressure ratings of thepressure-reducing valve shall be as defined in the documentslisted in Table 1.The pressure ratings(also called pressure-temperature ratings)establish the maximum allowable working(service)pressures of a component(valve,end connections,and so forth)at various temperatures.For a pressure-reducingval