1、 MSS SP-125-2010 Gray Iron and Ductile Iron In-Line, Spring-Loaded, Center-Guided Check Valves Standard Practice Developed and Approved by the Manufacturers Standardization Society of the Valve and Fittings Industry, Inc. 127 Park Street, NE Vienna, Virginia 22180 Phone: (703) 281-6613 Fax: (703) 28
2、1-6671 e-mail: infomss-hq.org www.mss-hq.org MSS STANDARD PRACTICE SP-125i This MSS Standard Practice was developed under the consensus of the MSS Technical Committee 106 and the MSS Coordinating Committee. The content of this Standard Practice is the result of the efforts of competent and concerned
3、 volunteers to provide an effective, clear, and non-exclusive specification that will benefit the industry as a whole. This MSS Standard Practice is intended as a basis for common practice by the manufacturer, the user, and the general public. The existence of an MSS Standard Practice does not in it
4、self preclude the manufacture, sale, or use of products not conforming to the Standard Practice. Mandatory conformance is established only by reference in a code, specification, sales contract, or public law, as applicable. “Other standards documents referred to herein are identified by the date of
5、issue that was applicable to this Standard Practice at the date of issue of this Standard Practice. See Annex B. This Standard Practice shall remain silent on the applicability of those other standards of prior or subsequent dates of issue even though applicable provisions may not have changed. Refe
6、rences contained herein which are bibliographic in nature are noted as supplemental in the text.” Unless otherwise specifically noted in this MSS SP, any standard referred to herein is identified by the date of issue that was applicable to the referenced standard(s) at the date of issue of this MSS
7、Standard Practice (See Annex B). In this Standard Practice all notes, annexes, tables, and figures are construed to be essential to the understanding of the message of the standard, and are considered part of the text unless noted as “supplemental“. All appendices, if included, that appear in this d
8、ocument are construed as “supplemental“. Supplemental information does not include mandatory requirements for this Standard Practice. Substantive changes in this 2010 edition are “flagged” by parallel bars as shown on the margins of this paragraph. The specific detail of the change may be determined
9、 by comparing the material flagged with that in the previous edition. U.S. customary units in this Standard Practice are the standard; metric (SI) units are for reference only. Any part of this Standard Practice may be quoted. Credit lines should read Extracted from MSS SP-125-2010 with permission o
10、f the publisher, Manufacturers Standardization Society of the Valves and Fittings Industry, Inc. Reproduction is prohibited under copyright convention unless written permission is granted by Manufacturers Standardization Society of the Valve and Fittings Industry Inc. Originally Approved: August 200
11、0 Copyright , 2000, 2010 by Manufacturers Standardization Society of the Valve and Fittings Industry, Inc. Printed in U.S.A. MSS STANDARD PRACTICE SP-125ii TABLE OF CONTENTS SECTION PAGE 1 SCOPE 1 2 VALVE STYLES AND CLASSES . 1 3 PRESSURE AND TEMPERATURE RATINGS 1 4 MATERIALS . 1 5 DESIGN . 2 6 WORK
12、MANSHIP 3 7 TESTS 4 8 MARKING . 4 9 PAINTING . 4 TABLE 1 CWP Ratings at 150F (65C), Non-Shock 2 2 Disc and Seat Materials 2 3 Face-to-Face Dimensions of Wafer-Style Check Valves . 3 4 Face-to-Face Dimensions of Compact Wafer-Style Check Valves . 3 5 Face-to-Face Dimensions of Globe-Style Check Valve
13、s . 3 6 Minimum Duration of Tests . 4 FIGURE A1 Wafer-Style 5 A2 Compact Wafer-Style . 5 A3 Flanged Globe-Style 5 A4 Wafer-Style 6 A5 Compact Wafer-Style . 6 A6 Flanged Globe-Style 6 ANNEX A Valve Types - - Figures A1 through A6 . 5 B Referenced Standards and Applicable Dates . 7 MSS STANDARD PRACTI
14、CE SP-1251 1. SCOPE 1.1 This Standard Practice covers in-line, internally spring-loaded, center-guided check valves made of gray iron or ductile iron. These valves, having the feature of limiting fluid flow to one direction only, are intended for use with clean fluids (i.e. fluids that do not contai
15、n solids), including potable water, waterworks, and other industrial applications, in horizontal and vertical installations. 2. VALVE STYLES AND CLASSES 2.1 Valve styles The valve styles included in this Standard Practice are determined by the configuration of the body. 2.1.1 Wafer Wafer-style check
16、 valves have a single flange body with an outside diameter equal to that of the mating pipe flanges. The valve body may be designed with holes passing through the body (see Figure A1) or with threaded lugs. The size range for wafer-style check valves is NPS 2-10 (DN 50-250). 2.1.2 Compact Wafer Comp
17、act wafer-style valves have a reduced outside body diameter, or slots, to provide bolt clearance for long bolts or studs (see Figure A2). The size range for compact wafer-style check valves is NPS 2-10 (DN 50-250). 2.1.3 Globe Globe-style check valves have two integrally cast flanges and a rounded-c
18、enter body section to provide increased flow area around the valve disc (see Figure A3). The size range of globe-style check valves is NPS 2-42 (DN 50-1050). 2.2 Flange Classes Valve end connections shall conform to the following requirements. 2.2.1 Wafer-style valves shall have bolt holes or thread
19、ed holes in accordance with ASME B16.1 for gray iron, Class 125 or 250 and in accordance with ASME B16.42 for ductile iron, Class 150 or 300. 2.2.2 Compact wafer-style valves shall have a reduced body diameter to accommodate flange bolts in accordance with ASME B16.1 for gray iron, Class 125 or 250
20、or ASME B16.42 for ductile iron, Class 150 or 300. 2.2.3 Globe-style flange dimensions shall be in accordance with ASME B16.1 for gray iron, Class 125 or 250 and in accordance with ASME B16.42 for ductile iron, Class 150 or 300. For sizes above NPS 24 (DN 600), ductile iron flange dimensions shall b
21、e in accordance with ASME B16.1. 2.2.5 Gaskets Full face or ring gaskets are required between the valve ends and the mating pipeline flanges to obtain a pressure tight joint. 3. PRESSURE AND TEMPERATURE RATINGS 3.1 The CWP ratings for various valve flange classes are specified in Table 1. 3.2 The ch
22、eck valves in this Standard Practice are intended for use in clean fluids with a temperature between 33F and 150F (1C and 65C). For elevated temperature installations, the manufacturer should be consulted. 4. MATERIALS 4.1 General This Standard Practice is intended to cover the minimum mechanical an
23、d chemical requirements for the items depicted in Figures A4, A5, and A6. GRAY IRON AND DUCTILE IRON, IN-LINE, SPRING-LOADED, CENTER-GUIDED CHECK VALVES MSS STANDARD PRACTICE SP-1252 TABLE 1 CWP Ratings at 150oF (65oC), Non-Shock FLANGE CLASS BODY MATERIAL SIZES CWP RATING ANDSEAT TEST PRESSURE SHEL
24、L TESTPRESSURE NPS DN PSI kPa PSI kPa 125 Gray Iron 2-12 50-300 200 1379 300 2068 14-42 350-1050 150 1034 225 1551 150 Ductile Iron 2-12 50-300 300 2068 450 3102 14-42 350-1050 250 1724 375 2586 250 Gray Iron 2-12 50-300 400 2758 600 4136 14-42 350-1050 300 2068 450 3102 300 Ductile Iron 2-12 50-300
25、 500 3447 750 5171 14-42 350-1050 400 2758 600 4136 4.1.1 Body The body shall be gray iron in accordance with ASTM A126 Class B or ductile iron in accordance with ASTM A395 or ASTM A536, Grades 70-50-05, 65-45-12 or 60-40-18. TABLE 2 Disc and Seat Materials MATERIAL ASTM NO. GRADE Bronze B62, B584 C
26、83600 B584 C84400 Aluminum Bronze B148 C95500 Stainless Steel A351 CF8 A351 CF8M 4.1.2 Disc and Seat The disc and seat shall be copper alloy or stainless steel, as specified in Table 2. Other bronze alloys may be used provided the lead content is below 8 percent and the zinc content is below 16 perc
27、ent. 4.1.3 Spring The spring shall be per ASTM A313, Type 302, 304, 316, or 17-7PH. 4.1.4 Resilient Seat The resilient seating material shall be selected based on service conditions specified by the purchaser. 4.1.5 Guide Bushing Guide bushings shall be provided in the center trunnion of the valve b
28、ody and made from a copper alloy or stainless steel material suitable for use with the mating stem material. Bronze alloys shall contain less than 8 percent lead and 16 percent zinc. 5. DESIGN 5.1 General Valves shall be designed to prevent permanent distortion to the body, disc, or seat when subjec
29、ted to the test pressures specified in Table 1. Valves shall be designed to operate continuously at flow velocities of 10 ft/sec (3.05 m/sec) 5.2 Body Flanges Gray iron flanges shall be drilled in accordance with ASME B16.1 for Classes 125 and 250. Gray iron flanges shall be flat faced unless otherw
30、ise specified. Ductile iron flanges shall be drilled in accordance with ASME B16.42 for Classes 150 and 300. The flange and wafer end finishes shall be in accordance with MSS SP-6. 5.3 Discs Discs shall have integral or threaded stems, adequately guided for self-centering in the valve body. In the f
31、ull-open position, the seat port shall have a minimum area, not less than the area of a circle having a diameter equal to the nominal valve size. MSS STANDARD PRACTICE SP-1253 The valve disc or stem shall not extend past the valve ends when in the closed position. The valve shall include a stop feat
32、ure to limit disc travel in the full open position. 5.4 Seals Valve seats may incorporate an elastomeric seal. Elastomeric seals shall be bonded, vulcanized, or mechanically secured to the valve disc or seat. 5.5 Springs A valve spring shall be provided to provide positive closure of the valve in ho
33、rizontal and vertical flow-up applications. Vertical flow-down applications must be specified by the purchaser, in the event that a special spring is required. Springs shall be either helical or conical compression type with closed and ground ends, designed so that when the valve is fully open, the
34、individual coils will not be over stressed or near the solid height. 5.6 Face-to-Face Dimensions Face-to-face dimensions for valves are specified in Tables 3, 4, and 5. A plus or minus tolerance of 1/16 in. (1.6 mm) shall be allowed on NPS 10 (DN 250) and smaller and 1/8 in. (3.2 mm) on NPS 12 (DN 3
35、00) and larger. TABLE 3 Face-to-Face Dimensions of Wafer-Style Check Valves NPS Flange Class 125 ASME/ANSI B16.1-2005 Gray Iron Pipe Flanges and Flanged Fittings: Classes 25, 125, and 250 B16.42-1998 (R2006) Ductile Iron Pipe Flanges and Flanged Fittings: Classes 150 and 300 ASTM A126-04(2009) Stand
36、ard Specification for Gray Iron Castings for Valves, Flanges, and Pipe Fittings A313/A313M-08 Standard Specification for Stainless Steel Spring Wire A351/A351M-06 Standard Specification for Castings, Austenitic, for Pressure-Containing Parts A395/A395M-99(2009) Standard Specification for Ferritic Du
37、ctile Iron Pressure-Retaining Castings for Use at Elevated Temperatures A536-84(2009) Standard Specification for Ductile Iron Castings B62-09 Standard Specification for Composition Bronze or Ounce Metal Castings B148-97(2009) Standard Specification for Aluminum-Bronze Sand Castings B584-09a Standard
38、 Specification for Copper Alloy Sand Castings for General Applications MSS SP-6-2007 Standard Finishes for Contact Faces of Pipe Flanges and Connecting-End Flanges of Valves and Fittings SP-25-2008 Standard Marking System for Valves, Fittings, Flanges, and Unions MSS STANDARD PRACTICE SP-1258 ANNEX
39、B (Continued) Referenced Standards and Applicable Dates This Annex is an integral part of this Standard Practice and is placed after the main text for convenience. Publications of the following organizations appear on the previous page in this Annex: ANSI American National Standards Institute, Inc.
40、23 West 43rd Street, 4th Floor New York, NY 10036-7406 ASME American Society of Mechanical Engineers Thre Park Avenue New York, NY 10016-5990 ASTM ASTM International 100 Bar Harbor Drive West Conshohocken, PA 19428-2959 MSS Manufacturers Standardization Society of the Valve and Fittings Industry, In
41、c. 127 Park Street, N.E. Vienna, VA 22180-4602 Listing of MSS Standard Practices TITLE SP-6-2007 Standard Finishes for Contact Faces of Pipe Flanges and Connecting-End Flanges of Valves and Fittings SP-9-2008 Spot Facing for Bronze, Iron and Steel Flanges SP-25-2008 Standard Marking System for Valve
42、s, Fittings, Flanges, and Unions SP-42-2009 Corrosion Resistant Gate, Globe, Angle and Check Valves with Flanged and Butt Weld Ends (Classes 150, 300 & 600) SP-43-2008 Wrought and Fabricated Butt-Welding Fittings for Low Pressure, Corrosion Resistant Applications (Incl. 2010 Errata Sheet) SP-44-2010
43、 Steel Pipeline Flanges SP-45-2003 (R 2008) Bypass and Drain Connections SP-51-2007 Class 150LW Corrosion Resistant Flanges and Cast Flanged Fittings SP-53-1999 (R 2007) Quality Standard for Steel Castings and Forgings for Valves, Flanges, and Fittings and Other Piping Components - Magnetic Particle
44、 Examination Method SP-54-1999 (R 2007) Quality Standard for Steel Castings and Forgings for Valves, Flanges, and Fittings and Other Piping Components - Radiographic Examination Method SP-55-2006 Quality Standard for Steel Castings for Valves, Flanges, Fittings, and Other Piping Components - Visual
45、Method for Evaluation of Surface IrregularitiesSP-58-2009 Pipe Hangers and Supports - Materials, Design, Manufacture, Selection, Application, and Installation SP-60-2004 Connecting Flange Joint Between Tapping Sleeves and Tapping Valves SP-61-2009 Pressure Testing of Valves SP-65-2008 High Pressure
46、Chemical Industry Flanges and Threaded Stubs for Use with Lens Gaskets SP-67-2002a Butterfly Valves SP-68-1997 (R 2004) High Pressure Butterfly Valves with Offset Design SP-69-2003 Pipe Hangers and Supports - Selection and Application (ANSI-approved American National Standard) SP-70-2006 Gray Iron G
47、ate Valves Flanged and Threaded Ends SP-71-2005 Gray Iron Swing Check Valves, Flanged and Threaded Ends SP-72-2010 Ball Valves with Flanged or Butt-Welding Ends for General Service SP-75-2008 Specification for High-Test, Wrought, Butt-Welding Fittings SP-77-1995 (R 2000) Guidelines for Pipe Support
48、Contractual Relationships - Relationships and Responsibilities of the Pipe Hanger Contractor with the Purchasers Engineer or the Pipe Fabricator and/or Erector SP-78-2005a Gray Iron Plug Valves Flanged and Threaded Ends SP-79-2009 Socket Welding Reducer Inserts SP-80-2008 Bronze Gate, Globe, Angle,
49、and Check Valves SP-81-2006a Stainless Steel, Bonnetless, Flanged Knife Gate Valves SP-83-2006 Class 3000 Steel Pipe Unions Socket Welding and Threaded SP-85-2002 Gray Iron Globe & Angle Valves Flanged and Threaded Ends SP-86-2009 Guidelines for Metric Data in Standards for Valves, Flanges, Fittings, and Actuators SP-88-2010 (R 2001) Diaphragm Valves SP-89-2003 Pipe Hangers and Supports - Fabrication and Installation Practices SP-90-2000 Guidelines on Terminology for Pipe Hangers and Supports SP-91-2009 Guidelines for Manual Operation of Valves SP-92-1999 MSS Valve User G
