1、Designation: F 1793 97 (Reapproved 2004)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 F 1793; the number immediately following the designation ind
2、icates 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 (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification covers self-contained
3、 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
4、 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:2F 992 Specification for Valve Label Plates2.2 American National Standards Institute (ANSI):3B1.1 Un
5、ified Screw Threads (UN and UNR Thread Form)B1.20.1 Pipe Threads, General Purpose (Inch)B16.11 Forged Steel Fittings, Socket-Welding and ThreadedB16.25 Buttwelding EndsB16.34 ValvesFlanged, Threaded, and Welded End2.3 Military Standards and Specifications:4MIL-STD-167-1 Mechanical Vibrations of Ship
6、boardEquipment (Type IEnvironmental and Type IIInternally Excited)MIL-STD-740-1 Airborne Sound Measurements and Ac-ceptance Criteria of Shipboard EquipmentMIL-S-901 Shock Tests, H.I. (High-Impact); ShipboardMachinery Equipment and Systems, Requirements forMIL-F-1183 Fitting, Pipe, Cast Bronze, Silve
7、r-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 Silv
8、er 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
9、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-o
10、ff 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 auto-matic shut-off valves shall be as defined in the documents listedin Table 1.
11、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.3.1.6 seat tightnessthe ability of the automatic shut-offvalve to prevent leakage from the valve-inl
12、et to the valve-outlet.3.1.7 set pointa combination of inlet pressure and flow, atwhich the valve trips shut.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:1This specific
13、ation 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, 2004. Published May 2004. Originallyapproved in 1997. Last previous edition approved in 1997 as F
14、 1793 - 97.2For 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 Instit
15、ute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036.4Available from Standardization Documents Order Desk, Bldg. 4 Section D, 700Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United Stat
16、es.3.1.8.1 DiscussionA combination of inlet pressure-flow,at or 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 above
17、which the automatic shut-off valve will trip shut (valve will notremain open) regardless of influences tending to resist closuresuch as breakloose friction, corrosion, or sludge, and so forth.3.1.9 set-point rangethe range of set points over whichthe automatic shut-off valve can be adjusted. Express
18、ed as arange of flow rates at a given inlet pressure.4. Classification4.1 Automatic shut-off valves shall be of the followingtypes, styles, sizes, pressure ratings, and end connections:4.1.1 Types:4.1.1.1 Type IValves that can be adjusted or repairedwithout removing the valve from pipe line.4.1.1.2
19、Type IIValves that cannot be adjusted or repairedwithout removing the valve from pipe line.4.1.2 Styles:4.1.2.1 Style 1Automatic Reset ConstructionThesevalves are designed to limit the flow of air or nitrogen uponclosure to a small predetermined level. These valves resetautomatically once the servic
20、e line downstream is made air ornitrogen-tight and pressure is equalized across the valve.4.1.2.2 Style 2Manual Reset ConstructionThese valvesare designed to stop the flow of air or nitrogen upon closure.These valves must be manually reset.4.1.3 SizesAutomatic shut-off valves shall be of thefollowin
21、g NPS sizes:14 (13.5 mm),38 (17.2 mm),12 (21.3mm),34 (26.9 mm), 1 (33.7 mm), 114 (42.4 mm), 112 (48.3mm), and 2 (60.3 mm). Unless otherwise specified in 5.0, thevalve inlet size shall be the same as the outlet size.4.1.4 Pressure RatingsAutomatic shut-off valves shallhave pressure rating(s) selected
22、 (see 3.1.5) from Table 1. Thepressure rating(s) selected shall be specified in Section 5. Theinlet and outlet pressure ratings of the automatic shut-off valveshall be the same for any given valve.4.1.5 End ConnectionsAutomatic shut-off valves shallhave end connections selected from those listed in
23、Table 1 andspecified in Section 5.5. Ordering Information5.1 Ordering documentation for automatic shut-off valvesunder this specification shall include the following informa-tion, as required, to describe the equipment adequately:5.1.1 ASTM designation and year of issue,5.1.2 Valve type (see 4.1.1),
24、5.1.3 Valve style (see 4.1.2),5.1.4 Valve size (see 4.1.3),5.1.5 Valve pressure rating (see 4.1.4),5.1.6 End connections (see 4.1.5),5.1.7 Valve inlet operating pressure,5.1.8 Set point (see 3.1.7 and 7.2),5.1.9 Tamper-proof set point adjustment, if required (see6.3.2),5.1.10 Supplementary requireme
25、nts, if any (see S1 throughS4), and5.1.11 Maximum vibration frequency and displacement am-plitude, if other than specified (see S1.2).6. Valve Construction6.1 Valves shall incorporate the features specified in 6.2-6.16.6.2 Materials of ConstructionMaterial requirements forthe automatic shut-off valv
26、e shall be as follows: The pressure-containing envelope shall be 300 series corrosion-resistantsteel (304, 304L, 316, or 316L). Internal parts includingsprings, poppets, retainers, etc. shall be 300 series corrosion-resistant steel, nickel-aluminum-bronze, nickel-copper (70-30),or bronze. Other mate
27、rials for both the pressure-containingenvelope and internal parts may be selected to assure compat-ibility with the line medium, weldability, and to providecorrosion resistance without requiring painting, coating, orplating. Materials for contacting parts shall be selected tominimize electrolytic co
28、rrosion and galling.6.3 General Requirements:6.3.1 Automatic shut-off valves shall be self-contained,requiring no external power source for operation. The auto-matic shut-off valve shall be capable of meeting all require-ments of this specification and provide extended reliableoperation.6.3.2 Automa
29、tic shut-off valves shall incorporate a provi-sion for manually resetting. This shall constitute an isolatablebleed-by which is operable with the valve in the pipeline underpressure and which functions by equalizing pressure across thepoppet. Style 1 valves shall in addition, incorporate a provision
30、which automatically resets the valve, and which constitutes asmall non-isolatable bleed-by.6.4 ThreadsThreads shall be as specified in ANSI B1.1.Where necessary, provisions shall be incorporated to preventthe accidental loosening of threaded parts. The design shall besuch that standard wrenches can
31、be used on all external bolting.Lock-wire shall not be used. Any exposed threads shall beprotected by plastic caps for shipping.TABLE 1 Pressure Ratings for Automatic Shut-Off ValvesType of EndConnectionPressure RatingApplicable Documents forDimensional Details of EndConnectionsButt-welded ANSI B16.
32、34 Class 150,300, 400, 600, 900, 1500,2500, or 4500ANSI B16.25Socket-welded ANSI B16.34 Class 150,300, 400, 600, 900, 1500,2500, or 4500ANSI B16.11Threaded (taperedpipe thread)ANSI B16.34 Class 150,300, 400, 600, 900, 1500,or 2500ANSI B1.20.1 and ANSIB16.11Union-end,ASilver-brazedMIL-F-1183 (O-ring
33、type)400 lb/in.2(2.758 MPa)MIL-F-1183 (O-ring type)400 lb/in.2(2.758 MPa)Union-end,ASilver-brazed803-1385946 1500 lb/in.2(10.342 MPa)803-1385946 1500 lb/in.2(10.342 MPa)Union-end,ASilver-brazed803-1385943 3000 lb/in.2(20.684 MPa)803-1385943 3000 lb/in.2(20.684 MPa)Union-end,AButt/socket weld803-1385
34、884 6000 lb/in.2(41.369 MPa)803-1385884 6000 lb/in.2(41.369 MPa)Other, as specified As specified As specifiedAFor Union inlet and outlet end connections, only the pertinent dimensionslisted in the applicable documents (Military Specification or NAVSEA Require-ments) shall apply. The valve shall be s
35、upplied with the thread-pieces only, withoutthe tail-pieces and union-nuts.F 1793 97 (2004)26.5 InterchangeabilityThe automatic shut-off valve, in-cluding all associated piece parts, shall have part numberidentity, and shall be replaceable from stock or the manufac-turer on a nonselective and random
36、 basis. Parts having thesame manufacturers part number shall be directly interchange-able with each other with respect to installation (physical) andperformance (function). Physically interchangeable assem-blies, components, and parts are those which are capable ofbeing readily installed, removed or
37、 replaced without alteration,misalignment, or damage to parts being installed or to adjoin-ing parts. Fabrication operations such as cutting, filing, drilling,reaming, hammering, bending, prying, or forcing shall not berequired.6.6 Nonmetallic Element InterchangeabilityNonmetallicelements, including
38、 but not limited to, seat rings, poppet seatinserts, cushions, and O-rings shall be treated as separatelyidentified and readily replaceable parts.6.7 MaintainabilityMaintenance shall require standardtools to the maximum extent possible. Any special toolsrequired for maintenance shall be identified,
39、and shall besupplied as part of the valve.6.8 ReversibilitySeating inserts, if applicable, shall not bephysically reversible unless they are also functionally revers-ible to preclude incorrect assembly.6.9 AdjustmentsThere shall be no adjustments required inthe automatic shut-off valve during or aft
40、er assembly other thanthe set point.6.10 Pressure EnvelopeThe valve shall be designed topass a hydrostatic shell test at a pressure of at least 1.5 timesthe 100F (38C) pressure rating of the valve without damage.6.11 Body ConstructionAll pressure lines, including thereset bleed line, shall be intern
41、ally ported. The bonnet andbottom cap (where applicable) shall be attached to the body bybolting, threading, or threaded-union connections.6.12 Set-Point AdjustmentSet point shall be adjustablethrough the range specified in 7.4. Type I valves shall beadjustable with the valve in the line under press
42、ure. Type IIvalves may be removed from the line for adjustment. The setpoint shall incorporate right-hand threads so that a clockwiserotation increases the set point. Means shall be used to preventan accidental or inadvertent change in set point. The option ofa tamper-proof set-point adjustment (lea
43、d seal, and so forth)shall be available and shall be specified as in Section 5.6.13 Port ConfigurationThe automatic shut-off valveshall have in-line inlet and outlet ports.6.14 SpringsSpring incorporated in the automatic shut-offvalve shall not be compressed solid during operation. Springends shall
44、be squared and ground. Engagement or disengage-ment of parts against spring compression shall not be permit-ted.6.15 GuidingThe valve poppet shall be guided to preventbinding or seizing, and to ensure proper seating under alloperating conditions. Proper alignment of all internal operatingparts shall
45、 be maintained with interchangeable parts and underall tolerance stack-up conditions.6.16 AccessibilityType I automatic shut-off valve shall beaccessible for adjustment or service, without removing theautomatic shut-off valve from the line.7. Performance Requirements7.1 Automatic shut-off valves sha
46、ll meet the requirementsof 7.2-7.8.7.2 Set PointThe required set point as defined in 3.1.7,shall be as specified (see Section 5).7.3 Set-Point AccuracyThe set-point accuracy, as definedin 3.1.8, shall be plus or minus 10 % of the set point.7.4 Range of Set-Point AdjustmentAutomatic shut-offvalves sh
47、all be capable of meeting all performance require-ments when set at any point within plus or minus 25 % of thenominal specified set point.7.5 Trip Differential PressureThe pressure differential atwhich the automatic shut-off valve trips shut shall not exceedthe values specified in Table 2.7.6 Reset
48、PressureOnce shut, the automatic shut-off valveshall remain shut until the pressure across the valve isequalized.7.7 Seat TightnessOnce shut, and with the manuallyoperated isolatable bleed-by closed, the automatic shut-offvalve shall meet the following seat tightness requirements.Where necessary, le
49、akage measurement shall start after tem-perature stabilization.7.7.1 Style 1 ValvesFlow leakage shall not be less than2 % and no greater than 5 % of the set-point flow.7.7.2 Style 2 ValvesFlow leakage shall not exceed 60standard cubic inches per hour (SCIH), per inch of valve size.7.8 External LeakageThe automatic shut-off valve exter-nal leakage shall be bubble-tight at its operating pressureconditions over a 3-min period.8. Tests Required8.1 Each automatic shut-off valve must pass the testsoutlined in 8.2-8.6.8.2 Visual Examinatio
