1、MSS SP-81-2017 Stainless-Steel or Stainless-Steel-Lined, Bonnetless, Knife Gate Valves with Flanged Ends Standard Practice Developed and Approved by the Manufacturers Standardization Society of the Valve and Fittings Industry, Inc. 127 Park Street, NE Vienna, Virginia 22180-4602 Phone: (703) 281-661
2、3 Fax: (703) 281-6671 E-mail: standardsmsshq.org www.msshq.org MSS STANDARD PRACTICE SP-81i This MSS Standard Practice is maintained and was revised under the consensus of the MSS Technical Committee 409 and the MSS Coordinating Committee. This Standard Practice was originally developed by MSS Techn
3、ical Committee 114 and its maintenance transferred to Technical Committee 409 in 2012. The content of this Standard Practice is the resulting efforts of competent and experienced volunteers to provide an effective, clear, and non-exclusive standard that will benefit the industry as a whole. This MSS
4、 Standard Practice describes minimal requirements and 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 the manufacture, sale, or use of products not conforming to the Standard Pract
5、ice. Mandatory conformance to this Standard Practice is established only by reference in other documents such as a code, specification, sales contract, or public law, as applicable. MSS has no power, nor does it undertake, to enforce or certify compliance with this document. Any certification or oth
6、er statement of compliance with the requirements of this Standard Practice shall not be attributable to MSS and is solely the responsibility of the certifier or maker of the statement. “Unless indicated otherwise within this MSS Standard Practice, other standards documents referenced to herein are i
7、dentified by the date of issue that was applicable to this Standard Practice at the date of approval of this MSS Standard Practice (see Annex A). This Standard Practice shall remain silent on the validity of those other standards of prior or subsequent dates of issue even though applicable provision
8、s may not have changed.” By publication of this Standard Practice, no position is taken with respect to the validity of any potential claim(s) or of any patent rights in connection therewith. MSS shall not be held responsible for identifying any patent rights. Users are expressly advised that determ
9、ination of patent rights and the risk of infringement of such rights are entirely their responsibility. In this Standard Practice, all text, notes, annexes, tables, figures, and references are construed to be essential to the understanding of the message of the standard, and are considered normative
10、 unless indicated as “supplemental”. All appendices, if included, that appear in this document are construed as “supplemental”. Note that supplemental information does not include mandatory requirements. The SI (metric) units and U.S. customary units in this Standard Practice are regarded separately
11、 as the standard; each should be used independently of the other. Combining or converting values between the two systems may result in non-conformance with this Standard Practice. Substantive changes in this 2017 edition are “flagged” by parallel bars as shown on the margins of this paragraph. The s
12、pecific detail of the change may be determined by comparing the material flagged with that in the previous edition. Non-toleranced dimensions in this Standard Practice are nominal unless otherwise specified. Excerpts of this Standard Practice may be quoted with permission. Credit lines should read E
13、xtracted from MSS SP-81-2017 with permission of the publisher, Manufacturers Standardization Society of the Valve and Fittings Industry. Reproduction and/or electronic transmission or dissemination is prohibited under copyright convention unless written permission is granted by the Manufacturers Sta
14、ndardization Society of the Valve and Fittings Industry Inc. All rights reserved. Originally Published: August 1975 Current Edition Approved: January 2017 (April 2017) Current Edition Published: April 2017 MSS is a registered trademark of the Manufacturers Standardization Society of the Valve and Fi
15、ttings Industry, Inc. Copyright , 2017 by Manufacturers Standardization Society of the Valve and Fittings Industry, Inc. Printed in U.S.A. MSS STANDARD PRACTICE SP-81ii TABLE OF CONTENTS SECTION PAGE 1 SCOPE AND FIELD OF APPLICATION . 1 2 STANDARD UNITS . 1 3 PRESSURE RATING . 1 4 SIZE . 1 5 MARKING
16、 1 6 MATERIALS 2 7 DESIGN 2 8 WELDING 3 9 TOLERANCES . 3 10 PRODUCTION TESTS . 3 11 SHIPPING INFORMATION 3 TABLE 1 Valve Dimensions, Inches . 4 2 Valve Dimensions, Millimeters . 4 3 Materials 5 4 Equivalent Stainless Steel Grades . 5 ANNEX A Referenced Standards and Applicable Dates . 6 MSS STANDARD
17、 PRACTICE SP-811 STAINLESS-STEEL OR STAINLESS-STEEL-LINED, BONNETLESS, KNIFE GATE VALVES WITH FLANGED ENDS 1. SCOPE AND FIELD OF APPLICATION1.1 This Standard Practice covers all stainless-steel or stainless-steel-lined, cast, or fabricated bonnetless, knife gate valves with flanged ends from size NP
18、S 2 (DN 50) through NPS 36 (DN 900). 1.2 The valves identified in this Standard Practice are intended for use in applications where shock loadings are not encountered. Applications at conditions other than those specified in Section 3 require special design considerations. 2. STANDARD UNITSThe value
19、s stated in either U.S. customary units or SI (metric) units are to be regarded separately as the “standard”. Within the text, the SI (metric) units are shown in parenthesis. The values stated in each system are not exact equivalents; therefore, each system must be used independently of the other. C
20、ombining values from the two systems may result in non-conformance with this Standard Practice. 3. PRESSURE RATINGThis Standard Practice covers valves with a gauge pressure rating not exceeding the values in the following table, at temperatures between 32 F and 150 F (0 C and 66 C). U.S. Customary S
21、I (Metric) NPS psi DN bar 2 24 150 50 600 10.3 30, 36 100 750, 900 6.9 4. SIZEThe valve sizes in Table 1 (NPS) and Table 2 (DN) are the nominal sizes of the end connections. 5. MARKINGThe valve shall be marked in accordance with MSS SP-25, including the following requirements and modifications: a) M
22、anufacturers name or trademark/logo.b) The body material of construction or code. When more than one material or grade of material isused, each shall be identified. The material in contact with the fluid media shall be listed andidentified as “lining” on the name plate. It is not required to repeat
23、the material designation offabricated bodies.c) Marking to show “seat side” of valve. Since most valves are manufactured for closure in onedirection only, the valve shall be marked showing the “seat side” (downstream side) of thevalve in such a manner that the markings can be seen with the valve ins
24、talled in the pipeline.The user shall be responsible for correct directional installation. When bi-directionalperformance is required, testing in the reverse direction from the seat shall be as per agreementbetween the customer and the manufacturer. Markings shall still indicate the seat side of the
25、valve. Bi-directional designs do not require a flow direction indicator.MSS STANDARD PRACTICE SP-812 d) The valve shall be marked for installation purposes, indicating:1) Care to be taken in valve installation with respect to direction of closure.2) Care to be taken when installing studs or bolts in
26、 the tapped holes of the flange in the area ofthe chest to prevent chest damage. The “chest” is the body area between the packing chamberand the flanges.3) Packing nuts may require adjustment to obtain a tight seal.e) The stem material need not be listed.6. MATERIALS6.1 Materials used for major comp
27、onents of these valves are listed in Table 3. Equivalent stainless steel grades are listed in Table 4. 6.2 Materials for stainless-steel-lined knife gate valves, per Tables 3 and 4 of this Standard Practice, shall be by agreement between purchaser and manufacturer. 7. DESIGN7.1 Valves shall be all s
28、tainless steel or stainless-steel-lined, by agreement as per Section 6.2. All interior wetted surfaces, including raised faces, gasket and packing chamber surfaces shall be stainless steel. Liners shall be sealed to prevent external leakage. With the exception of hard facing overlays and coatings, a
29、ll internal wetted parts shall have a corrosion resistance at least equivalent to the trim items (gate and seat rings) or valve liner; whichever is considered to have the lesser corrosion resistance. Hard face overlays (Cobalt or Ni-Cr types) on valve seating surfaces or wear surfaces are acceptable
30、. Stem material shall be the manufacturers standard unless otherwise agreed upon between the manufacturer and purchaser. Coatings applied to internal wetted surfaces shall be by agreement between the manufacturer and user. Dimensions shall be in accordance with Table 1 (inches) or Table 2 (millimete
31、rs). 7.2 The design of all valves shall prevent permanent distortion of the body or seats when tested as specified in Section 10. Some permanent distortion of stainless-steel parts is acceptable during the shell test of Section 10.1 provided it can be demonstrated that there will be no further defor
32、mation upon subsequent pressure loadings. 7.3 When through-bolting is specified, valves shall have flange holes per ASME B16.5 for sizes NPS 2 (DN 50) through NPS 24 (DN 600) for Class 150, and per ASME B16.47, Series A for sizes larger than NPS 24 (DN 600), see Table 1 (NPS) and Table 2 (DN) notes;
33、 except flange bolt holes that contact the chest shall be tapped in accordance with Table 1 or Table 2 of this Standard Practice. 7.4 The valve port I.D. shall not be less than 90 percent (90%) of the nominal inside diameter of Schedule 40 pipe. 7.5 Because of variations in basic valve design, diffe
34、rential pressure, and valve accessibility, it is not possible to standardize the conditions under which a manually operated valve requires mechanical assistance. Consideration should be given to the use of mechanical assistance on all valves over NPS 8 (DN 200) when the differential pressure, during
35、 valve operation, approaches the valves rated working pressure. In addition, consideration should be given to the use of mechanical assistance on all NPS 16 (DN 400) valves and larger, regardless of differential pressure. MSS STANDARD PRACTICE SP-813 8. WELDINGAll body pressure boundary welds shall
36、be in accordance with the ASME Boiler and Pressure Vessel Code, Section IX. 9. TOLERANCESThe following tolerances shall be followed: Face-to-face: NPS 10 (DN 250) and smaller 0.06 in. (1.5 mm) NPS 12 (DN 300) and larger 0.12 in. (3.0 mm) Flange outside diameter: 0.06 in. (1.5 mm) Bolt circle diamete
37、r drilling: 0.06 in. (1.5 mm) Center-to-center of adjacent bolt holes: 0.03 in. (0.8 mm) 10. PRODUCTION TESTS10.1 Shell Test (Body) Each valve shall be hydrostatically pressure tested at 1.5 times the rated working pressure with no visible leakage allowed (leakage through the packing or gate seal sh
38、all not be cause for rejection). Tests shall be performed to the requirements of MSS SP-151. The test fluid shall be water (which may contain a corrosion inhibitor), kerosene, or another suitable fluid provided such fluid has viscosity that is not greater than that of water. The test fluid temperatu
39、re shall not exceed 125 F (50 C). 10.2 Seat Test After the shell test, each valve shall be hydrostatically pressure tested per the requirements of MSS SP-151. 11. SHIPPING INFORMATION11.1 Valve packing nuts may be loosened prior to shipment to extend packing life. These nuts may have to be adjusted
40、after installation. 11.2 Unless indicated otherwise, valves shall be shipped with covers to protect the raised face of the flanges. MSS STANDARD PRACTICE SP-814 TABLE 1 Valve Dimensions, Inches Valve Size (NPS) Flanges Face-to-FaceOutside Diameter(a)Raised Face Outside Diameter(a)Bolt Circle Diamete
41、r(a) Bolting Thickness Minimum (Includes 0.06 in. Raised Face) Quantity(a)Tap Size(b)Clearance Hole Diameter(a) 2 3 4 6.00 7.50 9.00 3.62 5.00 6.19 4.75 6.00 7.50 4 4 8 5/8-11 5/8-11 5/8-11 0.75 0.75 0.75 0.50 0.50 0.50 1.88 2.00 2.00 5 6 8 10.00 11.00 13.50 7.31 8.50 10.62 8.50 9.50 11.75 8 8 8 3/4
42、-10 3/4-10 3/4-10 0.88 0.88 0.88 0.63 0.63 0.63 2.25 2.25 2.75 10 12 14 16.00 19.00 21.00 12.75 15.00 16.25 14.25 17.00 18.75 12 12 12 7/8-9 7/8-9 1-8 1.00 1.00 1.12 0.75 0.75 0.81 2.75 3.00 3.00 16 18 20 23.50 25.00 27.50 18.50 21.00 23.00 21.25 22.75 25.00 16 16 20 1-8 118-7 118-7 1.12 1.25 1.25 0
43、.88 0.94 1.00 3.50 3.50 4.50 24 30 36 32.00 38.75 46.00 27.25 33.75 40.25 29.50 36.00 42.75 20 28 32 1-7 1-7 1-6 1.38 1.38 1.62 1.00 1.12 1.12 4.50 4.62 4.62 NOTES: (a) In conformance with ASME B16.5, Class 150 for sizes NPS 2 through NPS 24 and per ASME B16.47 Series A for sizes NPS 24. (b) Eight-t
44、hread series (8-UN) may be used for bolting greater than one inch, as recommended by ASME B16.5 and ASME B16.47 for steel flanges. TABLE 2 Valve Dimensions, Millimeters Valve Size (DN) Flanges Face-to-FaceOutside Diameter(a)Raised Face Outside Diameter(a) Bolt Circle Diameter(a) Bolting Thickness Mi
45、nimum (Includes 1.5 mm Raised Face) Quantity(a)Tap Size(b)(c)Clearance Hole Diameter(a)50 80 100 150.0 190.0 230.0 92.0 127.0 157.5 120.5 152.5 190.5 4 4 8 5/8-11 5/8-11 5/8-11 18.0 18.0 18.0 12.7 12.7 12.7 48.0 51.0 51.0 125 150 200 255.0 280.0 345.0 186.0 216.0 270.0 216.0 241.5 298.5 8 8 8 3/4-10
46、 3/4-10 3/4-10 22.0 22.0 22.0 16.0 16.0 16.0 57.0 57.0 70.0 250 300 350 405.0 485.0 535.0 324.0 381.0 413.0 362.0 432.0 476.0 12 12 12 7/8-9 7/8-9 1-8 26.0 26.0 28.4 19.1 19.1 20.6 70.0 76.0 76.0 400 450 500 600.0 635.0 700.0 470.0 533.5 584.5 540.0 578.0 635.0 16 16 20 1-8 118-7 118-7 28.4 32.5 32.
47、5 22.4 23.9 25.4 89.0 89.0 114.0 600 750 900 815.0 985.0 1170.0 692.5 857.0 1022.0 749.5 914.0 1086.0 20 28 32 1-7 1-7 1-6 35.5 35.5 42.0 25.4 28.4 28.4 114.0 117.0 117.0 NOTES: (a) In conformance with ASME B16.5, Class 150 for sizes DN 50 through DN 600 and per ASME B16.47 Series A for sizes DN 600
48、. (b) U.S. customary units apply, per ASME B16.5 and B16.47 bolting requirements. (c) Eight-thread series (8-UN) may be used for bolting greater than one inch, as recommended by ASME B16.5 and ASME B16.47 for steel flanges. MSS STANDARD PRACTICE SP-815 TABLE 3 Materials MATERIAL ASTM NUMBER Stainles
49、s-Steel Plate A240/A240M Stainless-Steel Bar A276/A276M Stainless-Steel Casting A743/A743M or A351/A351M Carbon-Steel Plate A283/A283M, A36/A36M, or A285/A285M Carbon-Steel Casting A216/A216M Bronze Casting B62 Iron Casting A126, Class B TABLE 4 Equivalent Stainless Steel Grades WROUGHT CAST 304 CF8 316 CF8M 317 CG8M 304L CF3 316L CF3M 317L CG3M MSS STANDARD PRACTICE SP-816 ANNEX A Referenced Standards and Applicable Dates This Annex is an integral part of this Standard Practice and is placed after the main text for convenience. Standard Name Descrip
