ASTM F1793-97(2021)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation:F1793 −97 (Reapproved 2021) An American National Standard
Standard Specification for
Automatic Shut-Off Valves (Also Known as Excess Flow
Valves, EFV) for Air or Nitrogen Service
This standard is issued under the fixed designation F1793; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript 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. Scope ASME B16.34 Valves — Flanged, Threaded, and Welding
End
1.1 This specification covers self-contained automatic shut-
2.3 Military Standards and Specifications:
off valves (also known as excess flow valves) for air or
MIL-STD-167-1 Mechanical Vibrations of Shipboard
nitrogen service. They are intended to be installed as safety
Equipment (Type I—Environmental and Type II—
devicestoquicklyandautomaticallyshutoffflowundercertain
Internally Excited)
excess flow conditions caused by a downstream failure or
MIL-STD-740-1 Airborne Sound Measurements andAccep-
casualty, such as a hose rupture.
tance Criteria of Shipboard Equipment
1.2 The values stated in inch-pound units are to be regarded
MIL-S-901 Shock Tests, H.I. (High-Impact); Shipboard Ma-
as standard. The values given in parentheses are mathematical
chinery Equipment and Systems, Requirements for
conversions to SI units that are provided for information only
MIL-F-1183 Fitting, Pipe, Cast Bronze, Silver-Brazing,
and are not considered standard.
General Specification for
1.3 This international standard was developed in accor-
2.4 Government Drawings:
dance with internationally recognized principles on standard-
Naval Sea Systems Command (NAVSEA)
ization established in the Decision on Principles for the
NAVSEA 803-1385884 Unions, Fittings and Adapters Butt
Development of International Standards, Guides and Recom-
and Socket Welding 6000 PSI, WOG, NPS
mendations issued by the World Trade Organization Technical
NAVSEA 803-1385943 Unions, Silver Brazing 3000 PSI,
Barriers to Trade (TBT) Committee.
WOG, NPS, for UT Inspection
NAVSEA 803-1385946 Unions, Bronze Silver Brazing,
2. Referenced Documents
WOG for UT Inspection
2.1 ASTM Standards:
3. Terminology
F992 Specification for Valve Label Plates
2.2 ASME Standards: 3.1 Definitions:
ASME B1.1 Unified Inch Screw Threads (UN, UNR, and
3.1.1 automatic shut-off valve, n—automatic shut-off valves
UNJ Thread Forms) covered by this specification trip shut in response to the
ASME B1.20.1 Pipe Threads, General Purpose, Inch
pressure differential across the valve.
ASME B16.11 Forged Fittings, Socket-Welding and
3.1.2 bubble-tight, n—no visible leakage over a 3-min
Threaded
period using either water submersion or the application of
ASME B16.25 Buttwelding Ends
bubble fluid for detection.
3.1.3 external leakage, n—leakage from the automatic shut-
off valve that escapes to atmosphere.
This specification is under the jurisdiction of ASTM Committee F25 on Ships
and Marine Technology and is the direct responsibility of Subcommittee F25.11 on
3.1.4 hydrostatic shell test pressure, n—the hydrostatic shell
Machinery and Piping Systems.
test pressure that the automatic shut-off valve is required to
Current edition approved Jan. 1, 2021. Published January 2021. Originally
ɛ1 withstand without damage.Automatic shut-off valve operation
approved in 1997. Last previous edition approved in 2016 as F1793 – 97 (2016) .
DOI: 10.1520/F1793-97R21. is not required during application of shell test pressure, but it
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
must meet all performance requirements after the shell test
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
pressure has been removed.
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website.
Available from American Society of Mechanical Engineers (ASME), ASME
International Headquarters, Two Park Ave., New York, NY 10016-5990, http:// Available from DLA Document Services, Building 4/D, 700 Robbins Ave.,
www.asme.org. Philadelphia, PA 19111-5094, http://quicksearch.dla.mil.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F1793−97 (2021)
3.1.5 pressure ratings, n—the pressure ratings of the auto- 4.1.2.1 Style 1—Automatic Reset Construction—These
maticshut-offvalvesshallbeasdefinedinthedocumentslisted valves are designed to limit the flow of air or nitrogen upon
in Table 1. The pressure ratings (also called pressure- closure to a small predetermined level. These valves reset
temperatureratings)establishthemaximumallowableworking automatically once the service line downstream is made air or
(service) pressures of a component (valve, end connections, nitrogen-tight and pressure is equalized across the valve.
and so forth) at various temperatures. 4.1.2.2 Style 2—Manual Reset Construction—These valves
are designed to stop the flow of air or nitrogen upon closure.
3.1.6 seat tightness, n—the ability of the automatic shut-off
These valves must be manually reset.
valve to prevent leakage from the valve-inlet to the valve-
4.1.3 Sizes—Automatic shut-off valves shall be of the fol-
outlet.
1 3 1
lowing NPS sizes: ⁄4 (13.5 mm), ⁄8 (17.2 mm), ⁄2 (21.3 mm),
3.1.7 set point, n—a combination of inlet pressure and flow,
3 1 1
⁄4(26.9mm),1(33.7mm),1 ⁄4(42.4mm),1 ⁄2(48.3mm),and
at which the valve trips shut.
2 (60.3 mm). Unless otherwise specified in 5.0, the valve inlet
3.1.8 set-point accuracy, n—the band of accuracy of the
size shall be the same as the outlet size.
automatic shut-off valve expressed as a range of flow rates at a
4.1.4 Pressure Ratings—Automatic shut-off valves shall
given inlet pressure, established by the following two points:
have pressure rating(s) selected (see 3.1.5) from Table 1. The
3.1.8.1 A combination of inlet pressure-flow, at or below
pressure rating(s) selected shall be specified in Section 5. The
which the automatic shut-off valve will not trip shut (valve will
inlet and outlet pressure ratings of the automatic shut-off valve
remainopen)regardlessofinfluencessuchasspringrelaxation,
shall be the same for any given valve.
mechanical shock or vibration, and so forth.
4.1.5 End Connections—Automatic shut-off valves shall
3.1.8.2 A combination of inlet pressure-flow, at or above
have end connections selected from those listed in Table 1 and
which the automatic shut-off valve will trip shut (valve will not
specified in Section 5.
remain open) regardless of influences tending to resist closure
such as breakloose friction, corrosion, or sludge, and so forth.
5. Ordering Information
3.1.9 set-point range, n—the range of set points over which
5.1 Ordering documentation for automatic shut-off valves
the automatic shut-off valve can be adjusted. Expressed as a
under this specification shall include the following
range of flow rates at a given inlet pressure.
information,asrequired,todescribetheequipmentadequately:
5.1.1 ASTM designation and year of issue,
4. Classification
5.1.2 Valve type (see 4.1.1),
4.1 Automatic shut-off valves shall be of the following
5.1.3 Valve style (see 4.1.2),
types, styles, sizes, pressure ratings, and end connections:
5.1.4 Valve size (see 4.1.3),
4.1.1 Types:
5.1.5 Valve pressure rating (see 4.1.4),
4.1.1.1 Type I—Valves that can be adjusted or repaired
5.1.6 End connections (see 4.1.5),
without removing the valve from pipe line.
5.1.7 Valve inlet operating pressure,
4.1.1.2 Type II—Valves that cannot be adjusted or repaired
5.1.8 Set point (see 3.1.7 and 7.2),
without removing the valve from pipe line.
5.1.9 Tamper-proof set point adjustment, if required (see
4.1.2 Styles:
6.3.2),
5.1.10 Supplementary requirements, if any (see S1 through
TABLE 1 Pressure Ratings for Automatic Shut-Off Valves
S4), and
Applicable Documents for 5.1.11 Maximum vibration frequency and displacement
Type of End
Pressure Rating Dimensional Details of End
amplitude, if other than specified (see S1.2).
Connection
Connections
Butt-welded ASME B16.34 Class 150, ASME B16.25
6. Valve Construction
300, 400, 600, 900,
1500, 2500, or 4500
6.1 Valves shall incorporate the features specified in 6.2 –
Socket-welded ASME B16.34 Class 150, ASME B16.11
6.16.
300, 400, 600, 900,
1500, 2500, or 4500
6.2 Materials of Construction—Material requirements for
Threaded (tapered ASME B16.34 Class 150, ASME B1.20.1 and ASME
pipe thread) 300, 400, 600, 900, B16.11
the automatic shut-off valve shall be as follows: The pressure-
1500, or 2500
containing envelope shall be 300 series corrosion-resistant
A
Union-end, MIL-F-1183 (O-ring type) MIL-F-1183 (O-ring type)
2 2
Silver-brazed
steel (304, 304L, 316, or 316L). Internal parts including
400 lb/in. (2.758 MPa) 400 lb/in. (2.758 MPa)
A 2 2
Union-end, 803-1385946 1500 lb/in. 803-1385946 1500 lb/in.
springs, poppets, retainers, etc. shall be 300 series corrosion-
Silver-brazed
(10.342 MPa) (10.342 MPa)
resistantsteel,nickel-aluminum-bronze,nickel-copper(70-30),
A 2 2
Union-end, 803-1385943 3000 lb/in. 803-1385943 3000 lb/in.
Silver-brazed
or bronze. Other materials for both the pressure-containing
(20.684 MPa) (20.684 MPa)
A 2 2
Union-end, 803-1385884 6000 lb/in. 803-1385884 6000 lb/in.
envelope and internal parts may be selected to assure compat-
Butt/socket weld
(41.369 MPa) (41.369 MPa)
ibility with the line medium, weldability, and to provide
Other, as specified As specified As specified
corrosion resistance without requiring painting, coating, or
A
For Union inlet and outlet end connections, only the pertinent dimensions listed
plating. Materials for contacting parts shall be selected to
in the applicable documents (Military Specification or NAVSEA Requirements)
shall apply. The valve shall be supplied with the thread-pieces only, without the
minimize electrolytic corrosion and galling.
tail-pieces and union-nuts.
6.3 General Requirements:
F1793−97 (2021)
6.3.1 Automatic shut-off valves shall be self-contained, valves may be removed from the line for adjustment. The set
requiring no external power source for operation. The auto- point shall incorporate right-hand threads so that a clockwise
matic shut-off valve shall be capable of meeting all require- rotation increases the set point. Means shall be used to prevent
ments of this specification and provide extended reliable an accidental or inadvertent change in set point. The option of
operation. a tamper-proof set-point adjustment (lead seal, and so forth)
shall be available and shall be specified as in Section 5.
6.3.2 Automatic shut-off valves shall incorporate a provi-
sion for manually resetting. This shall constitute an isolatable
6.13 Port Configuration—The automatic shut-off valve
bleed-by which is operable with the valve in the pipeline under
shall have in-line inlet and outlet ports.
pressure and which functions by equalizing pressure across the
6.14 Springs—Spring incorporated in the automatic shut-off
poppet. Style 1 valves shall in addition, incorporate a provision
valve shall not be compressed solid during operation. Spring
which automatically resets the valve, and which constitutes a
ends shall be squared and ground. Engagement or disengage-
small non-isolatable bleed-by.
ment of parts against spring compression shall not be permit-
6.4 Threads—Threads shall be as specified in ASME B1.1.
ted.
Where necessary, provisions shall be incorporated to prevent
6.15 Guiding—The valve poppet shall be guided to prevent
the accidental loosening of threaded parts. The design shall be
binding or seizing, and to ensure proper seating under all
suchthatstandardwrenchescanbeusedonallexternalbolting.
operating conditions. Proper alignment of all internal operating
Lock-wire shall not be used. Any exposed threads shall be
parts shall be maintained with interchangeable parts and under
protected by plastic caps for shipping.
all tolerance stack-up conditions.
6.5 Interchangeability—The automatic shut-off valve, in-
6.16 Accessibility—Type I automatic shut-off valve shall be
cluding all associated piece parts, shall have part number
accessible for adjustment or service, without removing the
identity, and shall be replaceable from stock or the manufac-
automatic shut-off valve from the line.
turer on a nonselective and random basis. Parts having the
samemanufacturer’spartnumbershallbedirectlyinterchange-
7. Performance Requirements
able with each other with respect to installation (physical) and
7.1 Automatic shut-off valves shall meet the requirements
performance (function). Physically interchangeable
of 7.2 – 7.8.
assemblies, components, and parts are those which are capable
of being readily installed, removed or replaced without
7.2 Set Point—The required set point as defined in 3.1.7,
alteration, misalignment, or damage to parts being installed or
shall be as specified (see Section 5).
to adjoining parts. Fabrication operations such as cutting,
7.3 Set-Point Accuracy—The set-point accuracy, as defined
filing, drilling, reaming, hammering, bending, prying, or forc-
in 3.1.8, shall be plus or minus 10 % of the set point.
ing shall not be required.
7.4 Range of Set-Point Adjustment—Automatic shut-off
6.6 Nonmetallic Element Interchangeability—Nonmetallic
valves shall be capable of meeting all performance require-
elements, including but not limited to, seat rings, poppet seat
ments when set at any point within plus or minus 25 % of the
inserts, cushions, and O-rings shall be treated as separately
nominal specified set point.
identified and readily replaceable parts.
7.5 Trip Differential Pressure—The pressure differential at
6.7 Maintainability—Maintenance shall require standard
which the automatic shut-off valve trips shut shall not exceed
tools to the maximum extent possible. Any special tools
the values specified in Table 2.
required for maintenance shall be identified, and shall be
7.6 Reset Pressure—Once shut, the automatic shut-off valve
supplied as part of the valve.
shall remain shut until the pressure across the valve is
6.8 Reversibility—Seating inserts, if applicable, shall not be
equalized.
physically reversible unless they are also functionally revers-
7.7 Seat Tightness—Once shut, and with the manually
ible to preclude incorrect assembly.
operated isolatable bleed-by closed, the automatic shut-off
6.9 Adjustments—There shall be no adjustments required in
valve shall meet the following seat tightness requirements.
theautomaticshut-offvalveduringorafterassemblyotherthan
Where necessary, leakage measurement shall start after tem-
the set point.
perature stabilization.
7.7.1 Style 1 Valves—Flow leakage shall not be less than
6.10 Pressure Envelope—The valve shall be designed to
2 % and no greater than 5 % of the set-point flow.
pass a hydrostatic shell test at a pressure of at least 1.5 times
the 100°F (38°C) pressure rating of the valve without damage.
6.11 Body Construction—All pressure lines, including the
TABLE 2 Maximum Allowable Trip Differential Pressures
reset bleed line, shall be internally ported. The bonnet and
Maximum Inlet Operating Pressure, Maximum Allowable Trip Differential
bottom cap (where applicable) shall be attached to the body by
psi (MPa) Pressure, psi (kPa)
bolting, threading, or threaded-union connections.
400 (2.758) 15 (103)
1500 (10.342) 40 (276)
6.12 Set-Point Adjustment—Set point shall be adjustable
3000 (20.684) 60 (414)
through the range specified in 7.4. Type I valves shall be
6000 (41.369) 75 (517)
adjustable with the valve in the line under pressure. Type II
F1793−97 (2021)
7.7.2 Style 2 Valves—Flow leakage shall not exceed 60 Slowly increase flow until the valve trips shut. The valve shall
standard cubic inches per hour (SCIH), per inch of valve size. not close at less than 90 % of the set-point flow, and shall close
at no greater than 110 % of the set-point flow.
7.8 External Leakage—The automatic shut-off valve exter-
nal leakage shall be bubble-tight at its operating pressure
9. Marking
conditions over a 3-min period.
9.1 Body Markings—Valve bodies shall have the manufac-
8. Tests Required turer’s name or trademark, and flow arrow or “inlet” and
“outlet” cast, forged or stamped with round bottom dies on
8.1 Each automatic shut-off valve must pass the tests
them.
outlined in 8.2 – 8.6.
9.2 Identification Plate—An identification plate of
8.2 Visual Examination—The automatic shut-off valve shall
corrosion-resistant metal in accordance with Specification
be examined visually to determine conformance with the
F992; types I, II, III, or IVshall be permanently attached to the
ordering data, interface dimensions, and workmanship without
automatic shut-off valve and shall include the following
disassembly.
information (some or all information may instead be stamped
8.3 Hydrostatic Shell Test—The automatic shut-off valve
or etched directly on the outside surface of the automatic
shall be hydrostatically tested using water by applying a test
shut-off valve):
pressureequaltothe1.5timesthe100°F(38°C)pressurerating
9.2.1 Manufacturer’s name.
to the valve inlet and outlet to check its structural integrity.
9.2.2 ASTM designation and year of issue.
Pressureshallbeappliedforthreeminutes.Airornitrogenmay
9.2.3 Rated pressure.
be used in lieu of water, providing appropriate safety precau-
9.2.4 Set point and range of a
...