ASTM_F_1793_-_97_2010.pdf

Designation:F179397(Reapproved 2010)An American National StandardStandard Specification forAutomatic Shut-Off Valves(Also Known as Excess FlowValves,EFV)for Air or Nitrogen Service1This standard is issued under the fixed designation F1793;the number immediately following the designation indicates the year oforiginal adoption or,in the 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.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 This specification covers self-contained automatic shut-off valves(also known as excess flow valves)for air ornitrogen service.They are intended to be installed as safetydevices to quickly and automatically shut off flow under certainexcess flow conditions caused by a downstream failure orcasualty,such as a hose rupture.1.2 The values stated in this specification in inch-poundunits are to be regarded as the standard.The SI equivalentsshown in parentheses are provided for information only.2.Referenced Documents2.1 ASTM Standards:2F992 Specification for Valve Label Plates2.2 American National Standards Institute(ANSI):3ANSI B1.1 Unified Screw Threads(UN and UNR ThreadForm)ANSI B1.20.1 Pipe Threads,General Purpose(Inch)ANSI B16.11 Forged Steel Fittings,Socket-Welding andThreadedANSI B16.25 Buttwelding EndsANSI B16.34 ValvesFlanged,Threaded,and Welded End2.3 Military Standards and Specifications:4MIL-STD-167-1 Mechanical Vibrations of ShipboardEquipment(Type IEnvironmental and Type IIInternally Excited)MIL-STD-740-1 Airborne Sound Measurements andAccep-tance Criteria of Shipboard EquipmentMIL-S-901 Shock Tests,H.I.(High-Impact);Shipboard Ma-chinery Equipment and Systems,Requirements forMIL-F-1183Fitting,Pipe,Cast Bronze,Silver-Brazing,General Specification for2.4 Government Drawings:4NAVAL SEA SYSTEMS COMMAND(NAVSEA)NAVSEA 803-1385884 Unions,Fittings and Adapters Buttand Socket Welding 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 automatic shut-off valveautomatic shut-off valvescovered by this specification trip shut in response to thepressure differential across the valve.3.1.2 bubble-tightno visible leakage over a 3-min periodusing either water submersion or the application of bubble fluidfor detection.3.1.3 external leakageleakage from the automatic shut-offvalve that escapes to atmosphere.3.1.4 hydrostatic shell test pressurethe hydrostatic shelltest pressure that the automatic shut-off valve is required towithstand without damage.Automatic shut-off valve operationis not required during application of shell test pressure,but itmust meet all performance requirements after the shell testpressure has been removed.3.1.5 pressure ratingsthe pressure ratings of the automaticshut-off valves shall be as defined in the documents listed inTable 1.The pressure ratings(also called pressure-temperatureratings)establish the maximum allowable working(service)pressures of a component(valve,end connections,and soforth)at various temperatures.3.1.6 seat tightnessthe ability of the automatic shut-offvalve to prevent leakage from the valve-inlet to the valve-outlet.3.1.7 set pointa combination of inlet pressure and flow,atwhich the valve trips shut.1This specification is under the jurisdiction of ASTM Committee F25 on Shipsand Marine Technology and is the direct responsibility of Subcommittee F25.11 onMachinery and Piping Systems.Current edition approved May 1,2010.Published June 2010.Originallyapproved in 1997.Last previous edition approved in 2004 as F1793 97(2004).DOI:10.1520/F1793-97R10.2For referenced 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 Floor,New York,NY 10036,http:/www.ansi.org.4Available from Standardization Documents Order Desk,Bldg.4 Section D,700Robbins Ave.,Philadelphia,PA 19111-5094,Attn:NPODS.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.1.8 set point accuracythe band of accuracy of theautomatic shut-off valve expressed as a range of flow rates at agiven inlet pressure,established by the following two points:3.1.8.1 DiscussionAcombination of inlet pressure-flow,ator below which the automatic shut-off valve will not trip shut(valve will remain open)regardless of influences such as springrelaxation,mechanical shock or vibration,and so forth.3.1.8.2 A combination of inlet pressure-flow,at or abovewhich the automatic shut-off valve will trip shut(valve will notremain open)regardless of influences tending to resist closuresuch as breakl