1、 MSS SP-81-2013 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) 281-66
2、13 Fax: (703) 281-6671 E-mail: standardsmss-hq.org www.mss-hq.org MSS MSS STANDARD PRACTICE SP-81 i This MSS Standard Practice was developed under the consensus of the MSS Technical Committee 114 and the MSS Coordinating Committee. Maintenance of this Standard Practice is now the responsibility of M
3、SS Technical Committee 409, as of the date of this publication. 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 Standard Practice desc
4、ribes 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 Practice. Mandatory conforma
5、nce 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 other statement of complia
6、nce 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 identified by the date o
7、f 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 provisions may not have changed.
8、” 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 determination of patent right
9、s 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 unless indicated as “s
10、upplemental”. 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 as the standard; each
11、should be used independently of the other. Combining or converting values between the two systems may result in non-conformance with this Standard Practice. This Standard Practice has been substantially revised from the previous 2006a edition. It is suggested that if the user is interested in knowin
12、g what changes have been made, that direct page by page comparison should be made of this document and that of 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 li
13、nes should read Extracted from MSS SP-81-2013 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
14、Manufacturers Standardization Society of the Valve and Fittings Industry Inc. All rights reserved. Originally Published: August 1975 Current 2013 Edition Approved: October 2012 (Updated March 2013) Current 2013 Edition Published: May 2013 MSS is a registered trademark of the Manufacturers Standardiz
15、ation Society of the Valve and Fittings Industry, Inc. Copyright , 2013 by Manufacturers Standardization Society of the Valve and Fittings Industry, Inc. Printed in U.S.A. MSS STANDARD PRACTICE SP-81 ii TABLE OF CONTENTS SECTION PAGE 1 SCOPE AND FIELD OF APPLICATION 1 2 STANDARD UNITS . 1 3 PRESSURE
16、 RATING . 1 4 SIZE . 1 5 MARKING 1 6 MATERIALS 2 7 DESIGN . 2 8 WELDING . 2 9 TOLERANCES . 2 10 PRODUCTION TEST . 2 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
17、Applicable Dates . 6 MSS STANDARD PRACTICE SP-81 1 STAINLESS-STEEL OR STAINLESS-STEEL-LINED, BONNETLESS, KNIFE GATE VALVES WITH FLANGED ENDS 1. SCOPE AND FIELD OF APPLICATION 1.1 This Standard Practice covers all stainless-steel or stainless-steel-lined, cast, or fabricated bonnetless, knife gate va
18、lves with flanged ends from size NPS 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 conside
19、rations. 2. STANDARD UNITS The values 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 b
20、e used independently of the other. Combining values from the two systems may result in non-conformance with this Standard Practice. 3. PRESSURE RATING This Standard Practice covers valves with a gauge pressure rating not exceeding the values in the following table, at temperatures between 32 F and 1
21、50 F (0 C and 66 C). U.S. Customary SI (Metric) NPS psi DN bar 2 24 150 50 600 10.3 30, 36 100 750, 900 6.9 4. SIZE The valve sizes in Table 1 (NPS) and Table 2 (DN) are the nominal sizes of the end connections. 5. MARKING The valve shall be marked in accordance with MSS SP-25, including the followi
22、ng requirements and modifications: a) Manufacturers name or trademark/logo. b) The body material of construction or code, when more than one material or grade of material is used, shall each be identified. The material in contact with the fluid media shall be listed and identified as “lining” on the
23、 name plate. It is not required to repeat the material designation of fabricated bodies. c) Since most valves are manufactured for closure in one direction only, the valve shall be marked showing the “seat side” (downstream side) of the valve in such a manner that the markings can be seen with the v
24、alve installed in the pipeline. The user shall be responsible for correct directional installation. When bi-directional performance is required, testing in the reverse direction from the seat shall be as per agreement between the customer and the manufacturer. Markings shall still indicate the seat
25、side of the valve. Bi-directional designs do not require a flow direction indicator. 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 the tapped ho
26、les of the flange in the area of the chest to prevent chest damage. The “chest” is the body area between the packing chamber and the flanges. 3) Packing nuts may require adjustment to obtain a tight seal. e) The stem material need not be listed. MSS STANDARD PRACTICE SP-81 2 6. MATERIALS 6.1 Materia
27、ls used for major components 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. DESIGN 7.
28、1 Valves shall be all stainless 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 insure internal leakage cannot penetrate to the outer shell.
29、With the exception of hard facing overlays and coatings, all internal wetted parts shall have a corrosion resistance at least equivalent to the trim items (stem, gate, or seat rings) or valve liner; whichever is considered to have the lesser corrosion resistance. Hard face overlays (Cobalt or Ni-Cr
30、types) on valve seating surfaces or wear surfaces are acceptable. 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 (millimeters). 7.2 The design of all valves shall prevent permane
31、nt 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 deformation upon subsequent pressure loadings. 7.3 When thro
32、ugh-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); except holes that contact the chest shall be tapped in accord
33、ance with Table 1 or Table 2. 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, differential pressure, and valve accessibility, it is not possible to standardize the conditions under wh
34、ich 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 valve operation, approaches the valves rated working pressure. In addition, consideration should be
35、 given to the use of mechanical assistance on all NPS 16 (DN 400) valves and larger, regardless of differential pressure. 8. WELDING All body pressure boundary welds shall be in accordance with the ASME Boiler and Pressure Vessel Code, Section IX. 9. TOLERANCES The following tolerances shall be foll
36、owed: Face-to-face: NPS 10 (DN 250) and smaller +0.06 in. (+1.6 mm) NPS 12 (DN 300) and larger +0.12 in. (+3.2 mm) Flange outside diameter: +0.06 in. (+1.6 mm) Bolt circle diameter drilling: +0.06 in. (+1.6 mm) Center-to-center of adjacent bolt holes: +0.03 in. (+0.8 mm) 10. PRODUCTION TEST 10.1 She
37、ll 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 shall not be cause for rejection). MSS STANDARD PRACTICE SP-81 3 The test fluid shall be water (which may contain a cor
38、rosion inhibitor), kerosene, or another suitable fluid provided such fluid has a viscosity that is not greater than that of water. The test fluid temperature shall not exceed 125 F (50 C). 10.2 Seat Test After the shell test, each valve shall be hydrostatically pressure tested at 40 psi (2.8 bar) di
39、fferential pressure in the direction of closure. Maximum permissible leakage shall be 40 ml/min/NPS (1.6 ml/min/DN). Seat test duration shall be in accordance with MSS SP-61. 11. SHIPPING INFORMATION 11.1 Valve packing nuts may be loosened prior to shipment to extend packing life. These nuts may hav
40、e to be adjusted 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-81 4 TABLE 1 Valve Dimensions, Inches Valve Size (NPS) Flanges Face-to-Face Outside Diameter(a)Raised Face Outside Diameter(a)
41、 Bolt Circle Diameter(a) Bolting Thickness Minimum (Includes 0.06“ Raised Face) Quantity(a) Tap(b)Size 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.
42、50 11.75 8 8 8 3/4 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
43、7 1.12 1.25 1.25 0.88 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 24 and per ASME B16.47 Series A for sizes NPS 2
44、4. (b) 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. TABLE 2 Valves Dimensions, Millimeters Valve Size (DN) Flanges Face-to-Face Outside Diameter(a)Raised Face Outside Diameter(a) Bolt Circle Diameter(a) Bolt
45、ing Thickness Minimum (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
46、298.5 8 8 8 3/4 10 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 1
47、18 7 28.4 32.5 32.5 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 600 and per ASME B16.47 Series A f
48、or sizes DN 600. (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-81 5 TABLE 3 Materials MATERIAL ASTM
49、 NUMBER Stainless-Steel Plate A240/A240M Stainless-Steel Bar A276 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 CF-8 316 CF-8M 317 CG-8M 304L CF-3 316L CF-3M 317L CG-3M MSS STANDARD PRACTICE SP-81 6 ANNEX A Referenced Standards and Applicable Dates This Annex is an integral part of this Standard Practice and is p
