Standard Specification for Pressure-Reducing Valves for Air or Nitrogen Systems

SCOPE
1.1 This specification covers the design, construction, testing and operating requirements for self-contained pressure-reducing valves for air or nitrogen systems.  
1.2 The values stated in this specification in inch-pounds units are to be regarded as the standard. The SI equivalent shown in parenthesis are provided for information only.

General Information

Status
Historical
Publication Date
09-May-2000
Current Stage
Ref Project

Relations

Buy Standard

Technical specification
ASTM F1795-00 - Standard Specification for Pressure-Reducing Valves for Air or Nitrogen Systems
English language
8 pages
sale 15% off
Preview
sale 15% off
Preview

Standards Content (Sample)


NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
An American National Standard
Designation: F 1795 – 00
Standard Specification for
Pressure-Reducing Valves for Air or Nitrogen Systems
This standard is issued under the fixed designation F 1795; 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 (e) indicates an editorial change since the last revision or reapproval.
1. Scope NAVSEA 803-1385884 Unions, Fittings and Adapters Butt
and Socket Welding 6000 PSI, WOG, NPS
1.1 This specification covers the design, construction, test-
NAVSEA 803-1385943 Unions, Silver Brazing 3000 PSI,
ing, and operating requirements for self-contained pressure-
WOG, NPS, for UT Inspection
reducing valves for air or nitrogen systems.
NAVSEA 803-1385946 Unions, Bronze Silver Brazing,
1.2 The values stated in this specification in inch-pounds
WOG for UT Inspection
units are to be regarded as the standard. The SI equivalent
shown in parentheses are provided for information only.
3. Terminology
2. Referenced Documents 3.1 Definitions:
3.1.1 accuracy of regulation—the amount by which the
2.1 ASTM Standards:
2 downstream pressure may vary when the pressure-reducing
F 992 Specification for Valve Label Plates
valve is set at any pressure within the required set pressure
F 1685 Pressure-Reducing Manifolds for Air or Nitrogen
range and is subjected to any combination of inlet pressure,
Systems
flow demand, and ambient temperature variations within the
2.2 American National Standards Institute (ANSI):
specified limits.
B1.1 United Screw Threads (UN and UNR Thread Form)
3.1.2 bubble-sight—no visible leakage over a 3-min period
B1.20.1 Pipe Threads, General Purpose (Inch)
usingeitherwatersubmersionortheapplicationofbubblefluid
B16.11 Forged Steel Fittings, Socket-Welding and
for detection.
Threaded
3.1.3 external leakage—leakage from the pressure-reducing
B16.25 Buttwelding Ends
valve which escapes to atmosphere.
B16.34 Valves—Flanged, Threaded, and Welded End
3.1.4 fail-open flow capacity—the ability of the pressure-
2.3 Military Standards and Specifications:
reducing valve to pass flow under any given set of pressure
MIL-STD-167-1 Mechanical Vibrations of Shipboard
conditions when, as a result of mechanical failure, it has
Equipment (Type I—Environmental and Type II—
4 assumed a position of least resistance to flow.
Internally Excited)
3.1.5 flow capacity—the ability of the pressure-reducing
MIL-STD-740-1 Airborne Sound Measurements and Ac-
4 valve to pass flow under any given set of pressure conditions.
ceptance Criteria of Shipboard Equipment
3.1.6 flow rate demand—the amount of flow demanded by
MIL-S-901 Shock Tests, H.I. (High-Impact); Shipboard
4 the system at any given time downstream of the pressure-
Machinery, Equipment and Systems, Requirements for
reducing valve.
MIL-F-1183 Fittings, Pipe, Cast Bronze, Silver-Brazing,
4 3.1.7 flow rate demand range—the range over which the
General Specifications for
flow demand can vary.
2.4 Government Drawings:
3.1.8 hydrostatic shell test pressure(s)—The hydrostatic test
Naval Sea Systems Command (NAVSEA):
pressures that the inlet and outlet of the pressure-reducing
valve is required to withstand without damage. Pressure-
This specification is under the jurisdiction of ASTM Committee F25 on Ships
reducing valve operation is not required during application of
and MarineTechnology and is the direct responsibility of Subcommittee F25.11 on
shell test pressure, but the pressure-reducing valve must meet
Machinery and Piping Systems.
all performance requirements after the shell test pressure has
Current edition approved May 10, 2000. Published August 2000. Originally
been removed.
published as F 1795 - 97. Last previous edition F 1795 - 97.
Annual Book of ASTM Standards, Vol 01.07.
3.1.9 inlet operating pressure range—the range over which
Available from American National Standards Institute, 25 W. 43rd St., 4th
the inlet pressure supplied to the pressure-reducing valve can
Floor, New York, NY 10036.
vary under any operational conditions which the pressure-
AvailablefromStandardizationDocumentsOrderDesk,Bldg.4SectionD,700
Robbins Ave., Philadelphia, PA 19111–5094, Attn: NPODS. reducing valve can be subjected to in service.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
F1795–00
3.1.10 operating pressure(s)—the pressures within the 3.1.17 set pressure range—the range of set pressures (set
pressure-reducing valve during service. pressure limits) over which the pressure-reducing valve can be
adjusted while meeting the performance requirements speci-
3.1.11 pressure ratings—the pressure ratings of the
fied.
pressure-reducing valve shall be as defined in the documents
3.1.18 soft-seating insert—the insert, incorporated in either
listed in Table 1. The pressure ratings (also called pressure-
the poppet or the seat of the pressure-reducing valve, which
temperatureratings)establishthemaximumallowableworking
ensures bubble-tight seat tightness under all operating condi-
(service) pressures of a component (valve, end connections,
tions.
and so forth) at various temperatures. For a pressure-reducing
3.1.19 valve poppet—the part of the pressure-reducing
valve, the pressure ratings may not be identical for the valve
valve trim which established a rate of flow by moving toward
inlet and outlet.
or away from the valve seat.
3.1.12 pressure-reducing valve—a component which ac-
complishes automatic regulation of the downstream pressure.
4. Classification
In this component, the upstream pressure is reduced to the
4.1 Pressure-reducingvalvesshallbeofthefollowingtypes,
desired downstream pressure.
sizes, pressure ratings, and end connections, as specified in
3.1.13 pressure reversal—a condition in which pressure
Section 5.
exists at the outlet of a pressure-reducing valve when the
4.1.1 Types—Pressure-reducing valves shall be either Type
loading element is deactivated (set spring adjustment backed
I (inlet outlet end connections of the same pressure rating) or
off fully or dome charge vented off completely) and inlet
Type II (outlet end connection pressure rating lower than the
pressure is vented off.
inlet end connection rating) and specified in Section 5.
3.1.14 seat-tightness—the ability of the pressure-reducing
4.1.2 Sizes—Pressure-reducing valve sizes shall be ⁄8 NPS
valve to prevent leakage from the valve inlet to the valve
1 3 1
(10.2 mm), ⁄4 NPS (13.5 mm), ⁄8 NPS (17.2 mm), ⁄2 NPS
outlet.
3 1
(21.3 mm), ⁄4 NPS (26.9 mm), 1 NPS (33.7 mm), 1 ⁄4 NPS
3.1.15 self-contained pressure-reducing valve—a pressure-
(42.4 mm), 1 ⁄2 NPS (48.3 mm), and 2 NPS (60.3 mm).
reducingvalvethatdoesnotuseanexternalpowersource,such
4.1.3 Pressure Ratings—Pressure-reducing valves shall
as compressed air, electricity, or hydraulic fluid for operation,
have pressure rating(s) selected (see 3.1) from Table 1. The
but instead uses the line fluid for operation.
pressure rating(s) selected shall be specified in Section 5.
3.1.16 set pressure—the outlet pressure delivered by the
4.1.4 End Connections—Pressure-reducing valves shall
pressure-reducing valve at the time the pressure setting is
have end connections selected from those listed in Table 1 and
made. For the purposes of this specification, it will be assumed
specified in Section 5.
that the setting is made when there is no flow demand on the
pressure-reducing valve (“lock-up” condition), and the
5. Ordering Information
pressure-reducingvalveisatsurroundingambienttemperature.
5.1 Ordering documentation for pressure-reducing valves
under this specification shall include the following information
as required to describe the equipment adequately.
TABLE 1 Pressure Ratings for Pressure-Reducing Valve
5.1.1 ASTM designation and year of issue,
Applicable Documents for
5.1.2 Valve type (see 4.1.1),
Type of End
Pressure Rating Dimensional Details of End
Connection
5.1.3 Valve inlet and outlet sizes (see 4.1.2),
Connections
5.1.4 Pressure rating(s) (see 4.1.3),
Butt-welded ANSI B16.34 Class ANSI B16.25
5.1.5 Type of end connections (see 4.1.4),
150, 300, 400,
600, 900, 1500,
5.1.6 Inlet operating pressure range.
2500, or 4500
5.1.7 Set pressure and set pressure range, if other than
Socket-welded ANSI B16.34 Class ANSI B16.11
specified (see 7.1.3).
150, 300, 400,
600, 900, 1500,
5.1.8 Flow rate demand range (see 7.1.1, S1.1.2).
2500, or 4500
5.1.9 Accuracy of regulation required, if set pressure is
Threaded (tapered ANSI B16.34 Class ANSI B1.20.1 and ANSI
below 10 psig (see 7.1.2).
pipe thread) 150, 300, 400, B16.11
600, 900,
5.1.10 Tamper-proof set-point adjustment, if required (see
1500, or 2500
6.1.9),
A
Union end, MIL-F-1183 (O-ring MIL-F-1183 (O-ring type)
2 2
silver-brazed type) 400 lb/in. 400 lb/in. (2.758 MPa) 5.1.11 Supplementary requirements, if any (S1 through S4).
(2.758 MPa)
5.1.12 Maximum vibration frequency and displacement am-
A
Union end, 803-1385946 1500 803-1385946 1500
2 2 plitude, if other than specified (see S1.1.4).
silver-brazed lb/in. (10.342 MPa) lb/in. (10.342 MPa)
A
Union end, 803-1385943 3000 803-1385943 3000
2 2
silver-brazed lb/in. (20.64 MPa) lb/in. (20.64 MPa)
6. Valve Construction
A
Union end, 803-1385884 6000 803-1385884 6000
2 2
butt/socket weld lb/in. (41.369 MPa) lb/in. (41.369 MPa)
6.1 Valves shall incorporate the design features specified in
Other, as specified as specified as specified
6.1.1-6.1.19.
A
Forunioninletandoutletendconnections,onlythepertinentdimensionslisted
6.1.1 General Requirements—Pressure-reducing valves
intheapplicabledocuments(MilitarySpecificationorNAVSEArequirements)shall
shall be self-contained, requiring no external power source for
apply. The valve shall be supplied with the thread pieces only, without the tall
pieces and union nuts. operation. The pressure-reducing valve shall be capable of
F1795–00
meeting all requirements of this specification and provide to the seating surfaces would not require repair or replacement
extendedreliableoperationwhenprotectedbya5-µmnominal/ of the dome. Only a single dome penetration is allowed. The
18-µm absolute filter installed upstream and when subjected to valves shall be operable by a standard-size hex wrench or other
conditions specified in Section 5. suitable means. There shall be no external leakage past the
threads during dome bleeding. Flow from the bleed-off valve
6.1.2 Materials of Construction—Material requirements for
shall be ported in such a way that it does not impinge directly
the pressure-reducing valve shall be as follows: The pressure
on the person making the adjustment, cause excessive noise, or
containing envelope (body, gas dome, or spring housing) shall
potentially lead to ice formation within the dome loading
be 300 series corrosion-resistant steel (304, 304L, 316, or
circuit.
316L). Internal parts including springs, poppets, seal rings, and
6.1.11 Threads—Threads shall be as specified in ANSI
retainers shall be 300 series corrosion-resistant steel, nickel-
B1.1. Where necessary, provisions shall be incorporated to
aluminum bronze, nickel-copper (70–30), or bronze. Other
prevent the accidental loosening of threaded parts. The design
materials for both the pressure-containing envelope and inter-
shallbesuchthatstandardwrenchescanbeusedonallexternal
nal parts may be selected to assure compatibility with the line
bolting.Lock-wireshallnotbeused.Anyexposedthreadsshall
medium, weldability, and to provide corrosion resistance
be protected by plastic caps for shipping.
without requiring painting, coating, or plating. Materials for
6.1.12 Accessability—All internal parts of the pressure-
contacting parts shall be selected to minimize electrolytic
reducing valve shall be accessible for adjustment or service,
corrosion and galling.
without removing the pressure-reducing valve from the line.
6.1.3 Pressure Envelope—The pressure-reducing valve
6.1.13 Interchangeability—The pressure-reducing valve in-
shall be designed to pass a hydrostatic shell test at pressure(s)
cluding all associated piece parts, shall have part number
of at least 1.5 times the 100°F (38°C) pressure rating(s) of the
identity, and shall be replaceable from stock or the manufac-
valve without damage.
turer on a nonselective and random basis. Parts having the
6.1.4 Port Configuration—The pressure-reducing valve
samemanufacturer’spartnumbershallbedirectlyinterchange-
shall have in-line inlet and outlet ports.
able with each other with respect to installation (physical) and
6.1.5 Pressure Lines—All pressure lines in the pressure-
performance (function). Physically interchangeable assem-
reducing valve shall be internally ported.
blies, components, and parts are those that are capable of being
6.1.6 Soft-Seating Insert—A field replaceable soft-seating
readily installed, removed, or replaced without alternation,
insert shall be incorporated in the pressure-reducing valve.
misalignmentordamagetopartsbeinginstalledortoadjoining
Soft-seating inserts shall be protected from direct flow im-
parts. Fabrication operations such as cutting, filing, drilling,
pingement, excessive loading and extrusion, or any other effect
reaming, hammering, bending, prying, or forcing shall not be
jeopardizingtheirusefullife.Soft-seatinginsertsshallbeofthe
required.
simplest practical configuration to facilitate emergency re-
6.1.14 Nonmetallic Element Interchangeability—
placement manufacture where necessary.
Nonmetallicelements,includingbutnotlimitedto,soft-seating
6.1.7 Joints—The bonnet or spring housing and bottom cap
inserts, cushions, and O-rings, shall be treated as separately
shall be attached to the body by bolting, a threaded connection,
identified and readily replaceable parts.
or a threaded union connection.
6.1.15 Maintainability—Maintenance shall require standard
6.1.8 Springs—Any spring incorporated in the pressure-
tools to the maximum extent possible. Any special tools
reducing valve shall not be compressed solid during operation.
required for maintenance shall be identified, and shall be
Spring ends shall be squared and ground. Engagement or
supplied as part of the valve.
disengagement of parts against spring compression shall not be
6.1.16 Reversibility—Seating inserts shall not be physically
permitted.
reversible unless they are also functionally reversible to
6.1.9 Set Point Adjustment—For mechanical spring-loaded
preclude incorrect assembly.
pressure-reducing valves, the set point shall be adjustable
6.1.17 Adjustments—There shall be no adjustments re-
under pressure and shall incorporate right-hand threads so that
quired in the pressure-reducing valve during or after assembly
a clockwise
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.