MSS-SP-42-2004.pdf

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1、MSS SP-42-2004 Class 150 Corrosion Resistant Gate, Globe, Angle, and Check Valves with Flanged and Butt Weld Ends Standard Practice Developed and Approved by the Manufacturers Standardization Society of the Valve and Fittings Industry, Inc. 127 Park Street, NE Vienna, Virginia 221 80 Fax: (703) 281-

2、6671 e-mail: Phone: (703) 281-6613 www. mss-hq .com -,-,- This MSS Standard Practice was developed under the consensus of the MSS Technical Committee 114 and the MSS Coordinating Committee. The content of this Standard Practice is the result of the efforts of competent and concerned volunteers to p

3、rovide 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 itself preclude th

4、e manufac- ture, 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. This document has been substantively revised Fom the previous 1999 edition. It is suggeste

5、d that if the user is interested in knowing what changes have been made, direct page by page comparison should be made of this document. 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 standa

6、rd(s) at the date of issue of this MSS SP. (See Annex B.) Any part o f this standard may be quoted. Credit lines should read extracted from MSS SP-42, 2004 with permission o f the publisher, the Manufacturers Standardization Socieo. Reproduction prohibited under copyright convention unless written p

7、ermission is granted by the Manufacturers Standardization Society o f the Valve and Fittings Industry, Inc. Originally Approved OGtober, 1949 Copyright O, 1985 by Manufacturers Standardization Society of the Valve and Fittings Industry, Inc. Printed in U.S.A. i -,-,- MSS STANDARD PRACTICE SP-42 TABL

8、E OF CONTENTS SECTION PAGE SCOPE 1 STANDARD UNITS . 1 MATERIALS . 2 DESIGN . 3 PRESSURE TEMPERATURE RATINGS 6 WORKMANSHIP . 7 T E S T S . 7 M A R K I N G . 7 P A I N T I N G . 7 TABLE FIGURE ANNEX 1 Materials . 2 2 Flange Dimensions . 3 3 Stuffing Box Dimensions . 4 4 Pressure-Temperature Ratings 5

9、A1 A2 A3 A4 A5 A6 A7 A8 Gate Valves 8 Globe Valves . 8 Y-Pattern Globe Valve . 8 Angle Valve 8 Lift-Check Bolted Cover Plate . 9 Swing Check Bolted Cover Plate 9 Y-Pattern Swing Check Threaded Cover Plate . 9 Y-Pattern Swing Check Bolted Cover Plate 9 A Figures . 8 B Referenced Standards and Applica

10、ble Dates . 10 i i -,-,- MSS STANDARD PRACTICE SP-42 CLASS 150, CORROSION RESISTANT GATE, GLOBE, ANGLE AND CHECK VALVES WITH FLANGED AND BUTT WELD ENDS 1. SCOPE 1.1 This Standard Practice is intended to provide a vehicle for the standardization, to the extent indicated, of those features of the valv

11、es covered herein. The valves are made from corrosion resistant alloys whose properties are uniquely suited to the service into which they are placed. Chemical process and cryogenic fluid service constitute two such applica- tions. 1.2 This Standard Practice covers corrosion resis- tant alloy gate,

12、globe, angle and check valves con- forming to ASME B 16.34 with flanged and butt weld ends with pressure containing parts made from the alloys listed herein or in ASME B 16.34. 1.3 Valve Types and Sizes 1.3.1 Types The following valve types are covered herein and are illustrated in Figures 1 through

13、 8 in Annex A. (a) 1.3.2 Nominal P i p e Sizes a) 1/41NPS124 (81DN5600) gate valves. b) c) d) e) 1/41NPS124 (81DN5600) globe and angle valves. 1/2sNPSs24 (1 55DN1600) Y-pattern globe valves. 1/45NPS24 (8 5 DN5600) lift check valves. 1/2NPS124 (1 55DN5600) swing check valves. 2. STANDARD UNITS The va

14、lves stated in either U.S. customary units or metric units are to be regarded separately as the stan- dard. Within the text, the metric units are shown in parentheses. The values stated in each system are not exact equivalents; therefore, each system must be used independently of the other. Combinin

15、g valves from the two systems may result in nonconformance with this Standard Practice. a) Gates, outside screw and yoke design (OS&Y). 3. MATERIALS b) c) Globes, T, Y-pattern and angle, outside screw and yoke (OS&Y). Checks, lift, swing and Y-pattern. 3.1 General The specific body, bonnet or cover

16、plate and bolting material shall be produced in accor- dance with the applicable ASTM Specification listed herein or in materials group 2, 3, or 4 of ASME B 16.34. Users are cautioned against applications with fluid which may react harmfully with any mate- rials used in these valves. Consultation wi

17、th the manufacturer is advised to determine suitability in cases of doubt. (“)The valve sketches in Annex A are for the purpose of illustration and nomenclature only. They do not repre- sent any manufacturers product. 1 MSS STANDARD PRACTICE SP-42 2OCr-Cb NO8020 NO8020 NO8020 29Ni-20.5Cr- 3.17 CN7M

18、3.2 Castings Bodies, bonnets and cover plates shall be made of materials conforming to the requirements of specification listed in Table 1. Other parts in con- tact with the contained fluid shall be of material com- parable to the body material. All castings shall be clean, sound and shall be produc

19、ed to the quality level represented by MSS-SP-55. 3 SCu-2.5Mo I I I Vote: (“ASME B 16.34, Table 1 Material Group Number 3.3 Investment Castings When investment cast- ings are used for bodies, bonnets, cover plates or other pressure components of valves in sizes 4 NPS (DN 100) and smaller, the requir

20、ements of the ASTM specifications referred to in Table 1 shall be met ex- cept that it is permissible to determine mechanical and chemical properties from a master heat and to use a 1 inch x 0.25 inch diameter (25mm x 6.25mm diameter) tensile specimen in place of the standard 2-inch (62.5mm) tensile

21、 specimen in place of the stan- dard 2-inch (62.5mm) tensile specimen. A master heat is previously refined metal of a single hrnace charge. Tensile specimens shall be cast in molds of the same refractory as the casting and shall be heat treated with the casting. 3.4 WroughtParts Stems, packing gland

22、s and other wrought parts in contact with the contained fluids shall be of materials comparable to the body and as listed in Table 1. 3.5 Fabrication by Welding 3.5.1 Valve bodies, bonnets or cover plates fabri- cated by welding shall be in accordance with para- graph 2.1.6 of ASME B 16.34. 3 S.2 We

23、lding procedures and welders shall be quali- fied in accordance with ASME Boiler and Pressure Vessel Code, Section IX. 3.5.3 Where maximum corrosion resistance of welded austenitic stainless steel is desired it is advis- able to heat treat in such a fashion as to place all chromium carbide in soluti

24、on. See Para. UHA-105 in Section VIII-DrV. 1 of the ASME Boiler and Pres- sure Vessel Code for guidance on post weld heat treatment. 3.6 Bolting Body-bonnet and Body-cover plate bolts or studs sh(b)all be ASTM A193-Grade B8 or B8M. Nuts for body-bonnet bolting shall be ASTM A194, Grade 8, 8M, or SF.

25、 Gland bolting shall be Type 303, 304,305, or 316 conforming toASTMA193,A194, or A276. TABLE 1 MATERIALS ASTM Specification and GradeIType Nominal Casting Bar Forging Plate (b)Not to be used for pressure boundary items including bodies, bonnets and caps. 2 -,-,- MSS STANDARD PRACTICE SP-42 3.7 Handw

26、heels Handwheels shall be of steel malleable iron, ductile iron or aluminum. They shall be of the spoked design. 3.8 Gaskets Body-bonnet and body cover plate gaskets shall be suitable for the applicable rating listed herein, and for service with the types of fluids for which the valves are intended

27、to be used. 4. DESIGN 4.1 General Valves shall be designed so that dur- ing testing, permanent distortion of body, bonnet, coverplate or seat faces does not occur to the extent that valve function is impaired. cover material is not in the same material group as the body, its wall thickness shall sup

28、port the pres- sure-temperature rating of the body. 4.2.2 Additional metal thickness as needed for as- sembly, closing stresses, shapes other than circular, and stress concentrations shall be provided to meet the requirements of Section 4.1. 4.3 End Flanges 4.3.1 End flanges shall be integrally cast

29、 with the valve body or may be attached by welding. Welding shall be in accordance with Section 3.5. 4.2 Wall Thickness 4.2.1 The minimum wall thickness of the body, bon- net, and coverplates shall be in accordance with ASME B16.34. The body wall thickness governs the pressure-temperature rating. If

30、 the bonnet or 4.3.2 The outside diameter, thickness, raised face diameter, number, size and location of bolt holes and tolerances of end flanges shall be in accordance with ASME B 16.5. The integral flange dimensions listed in Table 2 shall be used for sizes NPS 114 through NPS 3/8 (DN 8 through DN

31、 10) which are not listed inASMEB16.5. TABLE 2 FLANGE DIMENSIONS General Note: See Section 4.3.2 for tolerances. Notes: (“Bolt holes for valves are located to straddle the center line (b)Dimensions for all larger sizes are per ASME B16.5. 3 -,-,- MSS STANDARD PRACTICE SP-42 4.3.4 Spot facing is not

32、necessary provided that the back side of the end flange is parallel to the flange face within 1 degree. Spot facing, if used, shall be in accordance with MSS-SP-9. US. Customary Units Valve Size, NPS 112 314 1 1114 1112 2 4.3.3 The flange face finish shall be in accordance with ASME B16.5. Face-to-F

33、ace, in. 4.50 5.00 5.75 6.50 7.25 8.50 Metric Units Valve Size, DN 15 20 25 32 4 0 5 0 114 127 146 165 184 216 Face-to-Face, mm. 4.4 WeldEnds Butt weld end dimensions and con- tour shall be as specified in ASME B16.25. The pipe schedule number shall be 40s in accordance with ASME B36.19M, unless oth

34、erwise specified in the Purchase Order. 4.5 Face-toFace and End-to-End Dimensions The face-to-face dimensions of valves shall be in accordance with ASME B 16.1 O except for “Y” pat- tern swing check valves with threaded cover plates as illustrated in Annex A, Figure 7. The face-to- face dimensions o

35、f “Y” pattern swing check valves with threaded cover plates shall be as follows: I I 4.6 Wedges and Discs. Gate valve wedges may be solid, split or double type. Solid wedges may be either plain having an I-shaped cross section or a tapered H, or inverted U cross section. Globe, angle, and lift check

36、 valve discs may be plug or spherical type or non-metallic. Swing check valve discs may be metallic with flat faces or non-metallic. Non- metallic discs shall be fitted to disc holders of corro- sion resistant metal equal to the body. Wedges and discs of all types shall be properly guided to the sea

37、ts. TABLE 3 STUFFING BOX DIMENSIONS 4 MSS STANDARD PRACTICE SP-42 4.7 Seats Seats may be integral with the valve vide adequate adjustment for progressive compres- body. When inserted body seats are furnished, us- sion of packing material. ers are cautioned to consider the effects of crevice corrosio

38、n. 4.8 two piece design. 4.9 Gland Bolting Studs, stud bolts hinge bolts, or 4.1 Backseating valve types, other than check headed bolts through drilled or slotted holes in the valves, shall be designed with a backseating feature. packing box flange may be used. In all cases gland Repacking under Pre

39、ssure is not recommended as a bolting shall be securely held in place and shall pro- Procedure. 4.10 StuDng Box The stuffing box bore for the corresponding stem diameter shall be as listed in Table 3. The nominal stuffing box depth shall be at least equivalent to 5 rings of square packing. Glands Gl

40、ands shall be bolted type, solid, or TABLE 4 PRESSURE-TEMPERATURE RATINGS U.S. Customary Units Metric Units I I 160- I 11.7 I 11.7 I 10.3 I 11.7 I 10.3 1 11.7 Note: (“See Section 5.3.1 5 -,-,- MSS STANDARD PRACTICE SP-42 4.12 Stems 4.12.1 Stems shall be threaded with single or mul- tiple Acme-type t

41、hread or 60-degree thread approxi- mating the Stub form. 4.12.2 Gate valve stems shall be of sufficient length so as to be at least flush with the top of the stem nut thread after the wedge has worn into its lowest posi- tion. 4.13 Packing Stem packing shall be of design and materials suitable for t

42、he primary service tempera- ture. 4.14 Gaskets Body-bonnet gaskets may be either full faced or extending to the inside of the bonnet bolts or retained in recess in the bonnet flange of the body. 5. PRESSURE-TEMPERATURE RATINGS 5.1 General Flanged end and butt weld end valves covered by this Standard

43、 Practice shall be designated as Class 150. Except as provided in Section 5.5, ratings for all valves are the maximum allowable working pressures, expressed as gage pressure, at the temperatures shown. For intermediate tempera- tures linear interpolation is permitted. The ratings listed in Table 4 a

44、re identical to those listed in ASME B16.34 Class 150 Standard Class for the applicable materials. 5.1.1 Flanged End Valves Valves conforming to the requirements of this Standard Practice for flanged end valves shall have the ratings as shown in Table 4. For an installed valve to merit the pressure-

45、tem- perature ratings listed herein, the bolting and gaskets for the end flanges must be in accordance with ASME B16.5. 5.2 The temperatures listed are the material tem- peratures of the pressure retaining structure. In view of the various environments in which piping compo- nents may be installed (

46、for example, insulated or uninsulated, heated or cooled externally) in estab- lishing pressure ratings, it is assumed that the mate- rial temperature of the pressure retaining structure is the temperature of the contained fluid. Use of a temperature other than that of the contained fluid is the resp

47、onsibility of the user and subject to the re- quirements of any applicable code. 5.3 Temperature Effects Some considerations of the effect of temperature in application are given below. Additional guidance can be found in ASME B16.5 as related to line flange joints. 5.3.1 Low Temperature For a mater

48、ial shown in Table 1, the pressure rating for service at any tem- perature below -20OF (-29OC) shall be no greater than the rating shown in the Table for -20F (-29OC). 5.3.2 Fluid Thermal Expansion Under certain conditions, some double seated valve designs are capable of sealing simultaneously again

49、st pressure differential from the bonnet section to the adjacent pipe in both directions. A circumstance in which the bonnet section is filled with liquid and subjected to an increase in temperature can result in a buildup of pressure in the bonnet section. An example is an isolation valve in a cryogenic fluid system ha