1、MIL-V-18436F 6 November 1987 SUPERSEDING MIL-V-18436E 2 March 1981 MILITARY SPECIFICATION VALVES, CHECK: BRONZE, CAST-IRON, AND STEEL BODY This specification is approved for use by the Naval Facilities Engineering Command, Department of the Navy, and is available for use by all Departments and Agenc
2、ies of the Department of Defense. 1. SCOPE AND CLASSIFICATION 1.1 Scope. This specification covers bronze, cast-iron, and steel body check valves with regrinding, renewable, or regrinding-renewable disks and seats. 1.2 Classification. The check valves shall be of the following groups, types, styles,
3、 trim, end connections, sizes, and classes, as specified (see 6.2). Group A - Bronze-body valves (1/8-4 inch, see table I). Group B - Cast-iron body valves (1/4-24 inch, see table II). Group C - Steel-body valves (1/4-12 inch, see table III). Type I - Lift check, horizontal installation. Type IS - L
4、ift check, spring-loaded, horizontal installation. Type II - Lift check, vertical installation. Type IIS - Lift check, spring-loaded, vertical installation. Type III - Swing check. Type IV - Tilting-disk check. Type V - Butterfly, spring-loaded, dual-disk check. Style A - Disk type, swing- or post-g
5、uided flow control device Style B - Piston type, cylinder-guided, air-cushioned flow control Style C - Ball type flow control device (types I and II). (types I, IS, II, IIS, and III). device (types I and II). IBeneficial comments (recommendations, additions, deletions) and any pertinent1 Idata which
6、 may be of use in improving this document should be addressed to: I IDocument Improvement Proposal (DD Form 1426) appearing at the end of this I ICommanding Officer (Code 156), Naval Construction Battalion Center, Port I IHueneme, CA 93043-5000, by using the self-addressed Standardization I Idocumen
7、t or by letter. I AMSC N/A FSC 4820 DISTRIBUTION STATEMENT A. Approved for public release; distribution is un1 imi ted. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-L - MIL-V-18436F Trim 1 - Nonmetallic disk; integral seat (group A). Trim 2 - Nonm
8、etallic disk; renewable seat ring (group 6, type III). Trim 3 - Metallic, regrinding disk; integral seat (group A). Trim 3A - Metallic, nonregrinding disk, renewable (group A, type III). Trim 4 - Metallic, regrinding disk; renewable seat ring (group A, Trim 5 - Metallic flow control device; renewabl
9、e seat ring Trim 6 - Metallic flow control device; integral or welded in seat Trim 7 - As specified (wafer-body valves). type 1). (groups B and C). (style B and C). End connections: Thread Flanged Solder (group A) Wafer body Butt welding (group C) Socket welding (group C 2 inch and smaller) . Hub, l
10、ead-calked (group B, type III) Sizes - 1/8 inch through 24 inches (see Tables I, II, and III). Classes - Class 125 to class 300 (see Tables I, II, and III). 2. APPLICABLE DOCUMENTS s J .U e 2.1 Government documents. 2.1.1 Specifications and standards. The following specification and standards form a
11、 part of this specification to the extent specified herein. Unless otherwise specified, the issues of these documents shall be those listed in the issue of the Department of Defense Index of Specifications and Standards (DODISS) and supplement thereto, cited in the solicitation. SPECIFICATION MI LI
12、TARY MIL-V-3 - Valves, Fittings, and Flanges (Except for Systems Indicated Herein); Packaging of. STANDARDS MILITARY MIL-STD-105 - Sampling Procedures and Tables for Inspection by MIL-STD-248 - Welding and Brazing Procedure and Performance Attributes. Qualification 2 Provided by IHSNot for ResaleNo
13、reproduction or networking permitted without license from IHS-,-,-L flIL-V-LB436F Lid 7777906 02732bL 5 MIL-V-18436F (Copies of specifications and standards, and other Government documents required by contractors in connection with specific acquisition functions should be obtained from the contracti
14、ng activity or as directed by the contracting activity.) 2.2 Other publications. specification to the extent specified herein. issues of the documents which are DOD adopted shall be those listed in the issue of the DODISS specified in the solicitation. specified, the issues of the documents not list
15、ed in the DODISS shall be the issue of the non-Government documents which is current on the date of the sol i ci tati on. a The following documents form a part of this Unless otherwise specified, the Unless otherwise AMERICAN NATIONAL STANDARDS INSTITUTE (ANSI) i - for Gas. A21.14 - Gray-Iron and Du
16、ctile-Iron Fittings, 3 Inch through 24 Inch 81.20.1 - Pipe Threads (Except Dryseal). B16.1 B16.5 - Steel Pipe Flanges and Flanged Fittings (Including Rating for Class 150, 300, 400, 600, 900, 1500, and 2500). 816.10 - Face-to-Face and End-to-End Dimensions of Ferrous Valves. B16.18 - Cast Copper All
17、oy Solder-Joint Pressure Fittings. 816.24 - Bronze Pipe Flanges and Flanged Fittings. 816.25 - Butt Welding Ends. B16.34 - Steel Valves (Flanged and Buttwelded End). B31.1 - Cast-Iron Pipe Flanges and Flanges Fittings. - Code for Pressure Piping. (Application for copies should be addressed to the Am
18、erican National Standards Institute, 1430 Broadway, New York, NY 10018.) a AMERICAN SOCIETY FOR TESTING AND MATERIALS (ASTM) - Gray Iron Castings for Valves, Flanges, and Pipe Fittings. A126 A182 - Forged or Rolled Alloy-Steel Pipe Flanges, Forged Fittings, and Valves and Parts for High-Temperature
19、Service. A276 - Stainless and Heat-Resisting Steel Bars and Shapes. A278 - Gray Iron Castings for Pressure-Containing Parts for Temperatures up to 650F (345C). A351 - Austenetic Steel Castings for High-Temperature Service. A479 - Stainless and Heat-Resisting Steel Bars and Shapes for Use in Boilers
20、and Other Pressure Vessels. A582 - Free Machining Stainless and Heat-Resisting Steel Bars, Hot-Rolled or Cold-Finished. B61 - Steam or Valve Bronze Castlngs. 862 - Composition Bronze or Ounce Metal Castings. 8140 - Copper-Zinc-Lead (Leaded Red Brass or Hardware Bronze) Rod, 8164 - Nickel-Copper Allo
21、y Rod and Bar. B584 - Copper Alloy Sand Castings for General Application. D2240 - Rubber Property-Durometer Hardness. Bars, and Shapes. 3 a Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,- NIL-V-LLI3bF LIB 7777706 0273262 7 M MIL-V-18436F (Applicatio
22、n for copies should be addressed to the American Society for Testing and Materials, 1916 Race Street, Philadelphia, PA 19103.) FLUID CONTROLS INSTITUTE Specification for Lift Disc Check Valves. (Application for copies should be addressed to the Fluid Controls Institute, 12 Bank Street, Summit, NJ 07
23、901.) MANUFACTURERS STANDARDIZATION SOCIETY OF THE VALVE AND FITTINGS INDUSTRY (MSS) SP-25 - Standard Marking System for Valves, Fittings, Flanges, and SP-45 - Bypass and Drain Connection Standard. SP-61 - Pressure Testing of Steel Valves. SP-71 - Cast Iron Swing Check Valves, Flanged and Threaded E
24、nds. SP-80 - Bronze Gate, Globe, Angle and Check Valves. Unions. (Application for copies should be addressed to the Manufacturers Standardization Society of the Valve and Fittings Industry, 127 Park Street, N.E. Vienna, VA 22180.) UNDERWRITERS LABORATORIES (UL) UL 312 - Swing Check Valves for Fire P
25、rotection Service. (Application for copies should be addressed to the Underwriters Laboratories Inc., 333 Pfingsten Road, Chicago, IL 60062.) (Non-Government standards and other publications are normally available from the organizations which prepare or which distribute the documents. These document
26、s also may be available in or through libraries or other informational services .) 2.3 Order of precedence. In the event of a conflict between the text of this specification and the references cited herein (except for associated detail specifications, specification sheets or MS standards), the text
27、of this specification shall take precedence. Nothing in this specification, however, shall supersede applicable laws and regulations unless a specific exemption has been obtained. 3. REQUIREMENTS 3.1 Description. The check valves shall consist essentially of a body, flow control device, and except a
28、s otherwise specified herein, a removable threaded cap or bolted cover. The valves shall permit flow in one direction only and shall close automatically when flow is reversed. The inter- relationship of groups, types, styles, trim, end connections, sizes, and classes shall be as specified in 1.2 and
29、 tables I, II, III, IV, V, and VI. 4 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-V-18436F 3.1.1 Lift checks. The design of lift check valves shall be in conformance with the Fluid Controls Institute specifications for lift disk check valves.
30、The seating surface in type I, IS, II, and IIS lift check valves shall be located on the horizontal segment of an integral bridge wa 1 separating the lower inlet chamber from the upper outlet chamber so that incoming flow will lift the flow control device upward from the seat. The flow control devic
31、e shall be beveled or flat metallic disk; a nonmetallic disk secured in a metallic disk holder; a metallic, piston-shaped or piston-guided disk; or a spherical metal ball in accordance with the specified style and trim. On style B valves, the design of the piston disk or guide shall provide a cushio
32、ning effect to minimize hammering resulting from repeated openings encountered under pulsating flow conditions. Spring-loaded type IS and 11s valves shall also be designed to cushion the disk on opening. The spring action on these valves shall, in addition, serve to effect rapid closure to eliminate
33、 hydraulic hammer of the disk caused by frequent flow reversals. all lift check valves, the lift of the flow control device in the direction perpendicular to the seat shall be not less than one-quarter the diameter of the seat port opening. On 3.1.2 Swing checks. The closure assembly on type III swi
34、ng check valves shall consist essentially of a strap or hanger; hinge pins; disk bolt and nut; meta lic disk with a nonmetallic facing or encapsulated steel disk with a flex ble hinge portion that bends a flexer as the flow opens up the valve. In type III valves, the fluid flow shall swing the closu
35、re assembly away from the seat The seating mechanism on all swing check valves shall be such that the disk assembly will close by the force of gravity when the valve is installed in a horizontal line. On regrinding type valves the seats shall be inclined such that the angle between the central axis
36、perpendicular to the seating surface and the centerline of the stream flow is not less than 30 degrees (O) nor more than 60“. All type III valves, except those with wafer bodies, shall be equipped with stops on the body, cover, or hanger strap to prevent disks from sticking or wedging in the wide op
37、en position. Swing check valves shall be suitable for installation both in a horizontal run of piping and for vertical runs in which the flow is the upward direction. All class 175, cast-iron body swing check valves, except clear-way swing check, when wide open, shall have face-to-face and end-to-en
38、d dimensions conforming to ANSI 816.10; valves having a clear-way swing check shall have face-to-face and end-to-end dimensions conforming to UL 312. Cast iron swing check valves shall be designed in accordance with MSS SP-71. 3.1.3 Tiltins-disk checks. When specified (see 6.21, the tilting-disk che
39、ck valve shall be free-acting cast-split body design, or spring-loaded cylindrical body design. The closure assembly on type IV, tilting disk check valves shall have a bottom hydraulic snubber designed to contact the disk during the last 10 percent of closure and control the final closing of the val
40、ve to prevent water hammer. The pivot point for the disk shall be located between the centerline of the flow and the top of the disk and shall be offset from the plane of the seating surface. The housing shall be equipped with flanges or welding ends, or shall be of wafer-type construction in accord
41、ance with the end connections specified. 5 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-V-LB43hF 98 97Ob 02732b4 O I MIL-V-18436F 3.2 First article, When specified in the contract or purchase order, a sample shall be subjected to first article
42、 inspection (see 4.2.1, 6.2, and 6.5). 3.3 Standard commercial product. The check valve shall, as a minimum, be in accordance with the requirements of this specification and shall be the manufacturers standard commercial product. Additional or better features which are not specifically prohibited by
43、 this specification but which are a part of the manufacturers standard commercial product, shall be included in the check valve being furnished. A standard commercial product is a product which has been sold or is being currently offered for sale on the commercial market through advertisements or ma
44、nufacturers catalogs, or brochures, and represents the latest production model. 3.4 Materials. Materials used shall be free from defects which would adversely affect the performance or maintainability of individual components or of the overall assembly. materials not specified herein shall be of the
45、 same quality used for the intended purpose in commercial practice. Unless otherwise specified herein, all equipment, material, and articles incorporated in the work covered by this specification are to be new and fabricated using materials produced from recovered materials to the maximum extent pos
46、sible without jeopardizing the intended use. The term “recovered materialsIg means materials which have been collected or recovered from solid waste and reprocessed to become a source of raw materials, as opposed to virgin raw materials. used or rebuilt products are allowed under this specification
47、unless otherwise specified. None of the above shall be interpreted to mean that the use of 3.4.1 Bronze. Bronze for group A valve bodies and caps shall conform to MSS SP-80. 3.4.2 Cast iron. Cast iron castings for group B valve bodies, shall conform to the requirements of ASTM A126, class B; ASTM A2
48、78, class 40; or better. 3.4.3 Steel. Steel for group C valves shall 3.4.4 Copper-nickel alloy. Copper-nickel al disks and seat rings shall conform ASTM 6584, al Alternate copper-nickel alloys used commercially acceptable provided alloying elements are in the copper and 24 to 35 percent for nickel.
49、conform to ANSI B16.34. oy specified in table IV for oy No. C97600 to C97800. for valve trim will be range of 57 to 63 percent for 3.4.5 Nickel-copper alloy. Nickel-copper al an optional trim material shall conform to ASTM 8164, class B. oy specified in table IV as 3.4.6 Stainless steel, When Specified (see 6.2), stainless steel trim specified in table IV for disk and seat rings on steel-body valves shall be type 304, 316, CF3M, or CF8M conforming to ASTM AlB2, A276, A351, or A
