1、 MSS SP-95-2014 Swaged(d) Nipples and Bull Plugs 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) 281-6613 Fax: (703) 281-6671 E-mail: standardsmss-hq.org www.ms
2、s-hq.org MSS STANDARD PRACTICE SP-95i This MSS Standard Practice was developed under the consensus of the MSS Technical Committees 105 and the MSS Coordinating Committee. The content of this Standard Practice is the resulting efforts of competent and experienced volunteers to provide an effective, c
3、lear, and non-exclusive standard that will benefit the industry as a whole. This MSS 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 pre
4、clude the manufacture, sale, or use of products not conforming to the Standard Practice. 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 unde
5、rtake, to enforce or certify compliance with this document. Any certification or other 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 wit
6、hin this MSS Standard Practice, other standards documents referenced to herein are identified 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 ot
7、her standards of prior or subsequent dates of issue even though applicable provisions 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 re
8、sponsible for identifying any patent rights. Users are expressly advised that determination 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 essenti
9、al to the understanding of the message of the standard, and are considered normative 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. U.S. customa
10、ry units in this Standard Practice are the standard; the SI (metric) units are for reference only. This Standard Practice has been substantially revised from the previous 2006a edition. It is suggested that if the user is interested in knowing what changes have been made, that direct page by page co
11、mparison 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 lines should read Extracted from MSS SP-95-2014 with permiss
12、ion 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 Standardization Society of the Valve and Fit
13、tings Industry Inc. All rights reserved. Originally Approved: March 1986 Originally Published: June 1986 Current Edition Approved: June 2013 (February 2014) Current Edition Published: September 2014 MSS is a registered trademark of Manufacturers Standardization Society of the Valve and Fittings Indu
14、stry, Inc. Copyright , 2014 by Manufacturers Standardization Society of the Valve and Fittings Industry, Inc. Printed in U.S.A. MSS STANDARD PRACTICE SP-95ii FOREWORD This document establishes a Standard Practice for Swaged (also known as Swage) Nipples and Bull Plugs, produced for a number of years
15、 by various manufacturers to varying dimensions, although basically similar in principle. Users should note that Swaged Nipples, and Bull Plugs furnished from existing stocks may have slightly different dimensions than shown herein. The values stated in either inch units or metric units are to be re
16、garded separately as standard. The values stated in each system are not exact equivalents; therefore, each system must be used independently of the other. Combining values from the two systems may result in non-conformance with the standard. Within the text, the (SI) metric units are shown in parent
17、hesis or within applicable tables; however, Bull Plug and Swaged Nipple sizes, within this Standard Practice, are identified by the “nominal pipe size” (NPS) only. Tables 1 through 3 show fittings with dimensional requirements and tolerances in U.S. Customary (i.e., inch) units. Tables A1 through A3
18、 show the dimensional fitting requirements and tolerances in (SI) metric (i.e., millimeter) units. NOTE: The drawings included within this Standard Practice are for the purpose of illustration only and not intended to exclude or limit any other design meeting this Standard Practice. In Memory of: Al
19、fred “Fred” S. Gilly 1929 2013 MSS STANDARD PRACTICE SP-95iii TABLE OF CONTENTS SECTION PAGE 1 SCOPE . 1 2 PRESSURE RATINGS . 1 3 SIZE . 1 4 MARKING 1 5 MATERIAL 2 6 DIMENSIONS 2 7 END PREPARATION 2 8 SURFACE QUALITY 2 9 DESIGN PROOF TEST 2 10 TESTING 3 TABLE 1 Swaged Nipple Dimensions 4 2 Bull Plug
20、 Dimensions 6 3 Tolerances . 7 1M Swaged Nipple Dimensions (millimeters) . 8 2M Bull Plug Dimensions (millimeters) 10 3M Tolerances (millimeters) 11 ANNEX A Referenced Standards and Applicable Dates . 12 MSS STANDARD PRACTICE SP-951 1. SCOPE 1.1 This Standard Practice covers dimensions, finish, tole
21、rances, marking, and material for carbon steel and alloy steel Swaged(1)Nipples (male end reducing fittings), NPS 1/4 through NPS 12 and Bull Plugs (hollow or solid male closures) NPS 1/8 through NPS 12. These fittings are made with ends that are threaded, beveled, square cut, grooved, or any combin
22、ation of these. Both concentric and eccentric Swaged Nipples are included. 1.2 Partial Compliance Fittings Fittings with special dimensions and fittings made from non-standard materials may be designed and manufactured by agreement between the manufacturer and the purchaser, provided they are marked
23、 in accordance with the requirements for partial compliance fittings of Section 4.1e. 2. PRESSURE RATINGS 2.1 The allowable working pressure for fittings designed in accordance with this Standard Practice shall be calculated as for straight seamless pipe of equal end preparation, in accordance with
24、the applicable sections of ASME B31.1, Power Piping, or ASME B31.3, Process Piping. The pipe wall thickness and type material shall be that for which the fittings have been ordered. Fittings shall be identified by pipe wall thickness and material grade in lieu of pressure rating. 2.2 The design of f
25、ittings may be established by mathematical analyses contained in nationally recognized pressure vessel or piping codes, or at the manufacturers option, by proof testing in accordance with Section 9. Records of design or successful proof tests shall be available at the manufacturers facility for insp
26、ection by the purchaser. Bull Plugs shall meet the additional requirement that the minimum thickness of the head shall be at least 1.5 times the thickness of the corresponding pipe schedule. For Bull Plugs that are drilled and tapped, the minimum thickness of the head shall be increased to accommoda
27、te the minimum L2 thread length as specified in ASME B1.20.1 3. SIZE 3.1 Within this Standard Practice, Bull Plug size is identified by the “nominal pipe size” (NPS) only. Swaged Nipples are also indicated by NPS only and are further identified with the large end size listed first, followed by the s
28、mall end size (see Section 4.1d). 4. MARKING 4.1 Each fitting shall be marked with prescribed information by raised lettering, electro-etching, vibro-etching, laser etching or other permanent method which will not result in harmful contamination or sharp discontinuities as follows: a) Manufacturers
29、name or trademark b) Material Identification Fittings shall be marked with the material grade in accordance with the applicable ASTM Fittings Specifications A234/A234M, A403/A403M, A420/A420M , A815/A815M, or A858/A858M (e.g., WPB, WP304, WPL6). The material lot or heat number traceable to the mater
30、ial shall be part of the material identification. c) Schedule number or nominal wall thickness designation of Swaged Nipple or Bull Plug. d) Size Nominal pipe size (NPS) of Bull Plug Nominal pipe size (NPS) Large end x small end of Swaged Nipples Example: 2 x 1 SWAGE(D) NIPPLES AND BULL PLUGS NOTE:
31、(1) Both “Swage” and “Swaged” are used within Industry terminology. Only “Swaged” is used in the body of this Standard Practice. MSS STANDARD PRACTICE SP-952 e) Product Conformance Fittings shall be marked with the symbol “SP95” to denote full conformance with this Standard Practice. Partial complia
32、nce fittings covered in Section 1.2 shall not be marked “SP95”. If marked with an ASTM designation, such marking shall be followed by the symbol “S58” as required by the “Supplementary Requirements” for Special Fittings in ASTM A960/A960M. 4.2 Where size and shape of fittings do not permit all the a
33、bove markings, they may be omitted in the reverse order given above. 4.3 Minimum permanent marking is the manufacturers name or trademark, material grade, heat number, and schedule number or nominal wall thickness. 4.4 Where steel stamps are used, care must be taken so that marking is not deep enoug
34、h to reduce wall thickness of the fitting below minimum allowed. 5. MATERIAL 5.1 The steel for Swaged Nipples and Bull Plugs shall consist of forgings, round or hex bars or seamless pipe or tube which conform to the requirements of ASTM A234/A234M, A403/A403M, A420/A420M, A815/A815M, A858/A858M or t
35、he corresponding ASME Specification. When Swaged Nipples and Bull Plugs are made of materials other than those referenced in this Standard Practice, they should be appropriately marked as agreed upon between the manufacturer and purchaser. 6. DIMENSIONS 6.1 The dimensions of Swaged Nipples and Bull
36、Plugs shall conform to Tables 1 or A1 and Tables 2 or A2, respectively. U.S. customary (inch) tolerances shall conform to Table 3 and metric (millimeter) tolerances shall conform to Table A3. 7. END PREPARATION 7.1 Pipe ends may be threaded, beveled for butt-welding, square cut (plain) for socket we
37、lding, grooved, or any combination thereof. 7.2 Threaded ends shall be in accordance with ASME B1.20.1. Threads shall be chamfered at the ends of the fitting to protect the first thread. The reference point for gauging threads is the last thread scratch on the chamfer cone. 7.3 Butt-welding ends sha
38、ll be in accordance with ASME B16.25. 7.4 Grooved ends shall be by agreement between the manufacturer and purchaser. 8. SURFACE QUALITY 8.1 Fittings supplied under this specification shall be in accordance with surface quality requirements of ASTM A960/A960M. 9. DESIGN PROOF TEST 9.1 Proof tests sha
39、ll be performed as set forth herein, when the manufacturer chooses proof testing to qualify the fitting design. 9.2 Test Assembly 9.2.1 Fittings selected for testing shall be representative of production and shall meet all the requirements of this Standard Practice and the applicable material specif
40、ication. The fittings shall be inspected for dimensional compliance to this Standard Practice. Full material specification test reports, including chemical analysis, tensile properties, and hardness property results shall be included in the records of these proof tests. 9.2.2 Straight seamless or we
41、lded pipe sections, whose calculated bursting strength is at least as great as the computed proof test pressure as calculated in Section 9.3 shall be welded to each end of the fitting to be tested. Any internal misalignment greater than 0.06 inch (1.6 mm) shall be reduced by taper boring at a slope
42、of 1:3. Length of pipe sections for closures shall be at least twice the pipe outside diameter (O.D.). 9.3 Test Procedure 9.3.1 The test fluid shall be water or other fluid used for hydrostatic testing. 9.3.2 Hydrostatic pressure shall be applied to the test assembly. The test is successful if the M
43、SS STANDARD PRACTICE SP-953 assembly withstands, without rupture, 105 percent (105%) of the computed test pressure defined below: DStP2Where: P = computed test pressure S = minimum tensile strength of the test fitting t = minimum wall thickness of the pipe that the fitting marking identifies D = spe
44、cified outside diameter of the pipe NOTE: Any dimensionally consistent system of units may be used. 9.3.3 As an alternative, if the pipe ruptures, or if sufficient pressure to rupture a part of the assembly cannot be attained, the test pressure is acceptable if a final test pressure is at least 105
45、percent (105%) of the computed proof test pressure. 9.4 Applicability of Test Results It is not necessary to conduct an individual test of fittings with all combinations of sizes, wall thickness, end connections and grade of steel. A successful proof test on one prototype fitting may represent other
46、s to the extent described herein. 9.4.1 One test fitting may be used to qualify similar ones, no smaller than one-half, nor larger than two times the nominal pipe size of the test fitting. 9.4.2 The untested fittings shall have a t/D ratio not less than one-half, nor more than three times the t/D ra
47、tio of the test fitting. 9.4.3 The pressure retaining capacity of a fitting made of various grades of material with similar mechanical properties will be directly proportional to the tensile properties of the various grades, provided the yield-to-tensile ratio is 0.84 or less for the material to be
48、extended under the proof test data. Hence, it is necessary to test a prototype in only a single grade to prove the geometric design of the fittings. 10. TESTING 10.1 Hydrostatic testing of fittings is not required in this Standard Practice. All fittings shall be capable of withstanding without leaka
49、ge, a test pressure equal to that prescribed in the specification for the pipe of equal end preparation, with which the fittings marking identifies. MSS STANDARD PRACTICE SP-954 TABLE 1 Swaged Nipple Dimensions Dimensions are in inches NPS Outside Diameter End-to-End“A” Large End Small End 2 x 1122.375 1.900 6.50 2 x 1142.375 1.660 6.50 2 x 1 2.375 1.315 6.50 2 x 3/4 2.375 1.050 6.50 2 x 1/2 2.375 0.840 6.50 2 x 3/8 2.375 0.675 6.50 2 x 1/4 2.375 0.540 6.50 2 x 1/8 2.375 0.405 6.50 212x 2 2.875 2.375 7.00 212x 1122.875 1.900 7.00 212x 1142.875 1.660
