1、A N AMER I CAN N A T I O N A L S T A N D A R DAN A M E RIC A N ASME B18.13-1996Revision of ASME B18.13-1987 (R1993)SCREWS AND WASHERASSEMBLIESSEMS(INCH SERIES)INTENTIONALLY LEFT BLANK The American Society of Mechanical Engineers AN AMERICAN NATIONAL STANDARD ASME 818.13-1 DUG Revision of ASME 818.13
2、-1987 (R1993) Date of Issuance: September 15, 1997 The 1996 edition of this Standard is being issued with an automatic addenda subscription service. The use of an addenda allows revisions made in response to public review comments or Committee actions to be published as necessary. The next edition o
3、f this Standard is scheduled for publication in 1999. ASME is the registered trademark of The American Society of Mechanical Engineers. This code or standard was developed under procedures accredited as meeting the criteria for American National Standards. The Consensus Committee that approved the c
4、ode or standard was balanced to assure that individuals from competent and concerned interests have had an opportunity to participate. The proposed code or standard was made available for public review and comment which provides an opportunity for additional public input from industry, academia, reg
5、ulatory agencies, and the public-at-large. ASME does not “approve,“ “rate,“ or “endorse“ any item, construction, proprietary device, or activity. ASME does not take any position with respect to the validity of any patent rights asserted in connection with any items mentioned in this document, and do
6、es not undertake to insure anyone utilizing a standard against liability for infringement of any applicable letters Patent, nor assume any such liability. Users of a code or standard are expressly advised that determination of the validity of any such patent rights, and the risk of infringement of s
7、uch rights, is entirely their own responsibility. Participation by federal agency representative(s) or personss) affiliated with industry is not to be interpreted as government or industry endorsement of this code or standard. ASME accepts responsibility for only those interpretations issued in acco
8、rdance with governing ASME procedures and policies which preclude the issuance of interpretations by individual volunteers. No part of this document may be reproduced in any form, in an electronic retrieval system or otherwise, without the prior written permission of the publisher. The American Soci
9、ety of Mechanical Engineers 345 East 47th Street, New York, NY 10017 Copyright 1997 by THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS All Rights Reserved Printed in U.S.A. FOREWORD (This Foreword is not part of ASME 818.13-1996.) American National Standards Committee B27 for the standardization of pla
10、in and lock washers was organized in March 1926 as Sectional Committee B27 under the aegis of the American Standards Association (later the United States of America Standards Institute and, as of October 6, 1969, the American National Standards Institute, Inc.) with the Society of Automotive Enginee
11、rs and the American Society of Mechanical Engineers as joint sponsors. (Since 1950, this Committee has also been assigned responsibility for standardization of washers and machine rings.) The Committee was reorganized in May 1928, at which time two subcommittees were established to carry on developm
12、ent work Subcommittee 11 on plain washers and Subcommittee 2 on lock washers. In 1940 the B27 Committee was reactivated and Subcommittee 2 proceeded to draft a proposal covering helical spring lock washers. It was further amended in 1943 and, following approval by the B27 Committee and sponsor organ
13、izations, accepted as an American Standard under the designation ASA B27.1-1994. A draft proposal completed by Subcommittee 2 in September 1949 incorporated requirements applicable to helical spring lock washers made from materials other than carbon steel and included specifications for tooth lock w
14、ashers, both helical spring and tooth lock washers, and machine screw assemblies. Subsequent to approval by the B27 Committee and sponsors, this proposal was forwarded to the American Standards Association and declared an American Standard on May 22, 1950. During the years 1951 through 1956, Subcomm
15、ittee 2 considered numerous refinements to the coverage for helical spring lock washers and heat treated machine screw and lock washer assemblies. A formal draft dated June 1957 was approved by letter ballot of the B27 Committee and the sponsor organizations and submitted to the American Standards A
16、ssociation for designation as an American Standard. This was granted on November 3, 1958. In 1961 a study group comprised of members of the B 18 and B27 Committees recommended that the screw and washer assemblies, commonly known as sems, be published as a separate document under the jurisdiction of
17、the B 18 Committee, but subject to approval of both Sectional Committees and the affected subcommittees thereof. This recommendation was accepted by the B27 and Bl8 Committees, respectively, on the 28th and 30th of November 1961. Subcommittee 272 of Committee B 18 was subsequently appointed. At the
18、initial meeting of Subcommittee 27 on February 1, 1962 a proposal was submitted consisting of pertinent data for lock washer sems extracted from ASA B27 .1-1958 and for plain washer sems proposed for inclusion in ASA B27 .2, plus information gleaned from 1 As of April 1, 1966, Subcommittee 1 was red
19、esignated Subcommittee 2 on plain washers; Subcommittee 2 was redesignated Subcommittee 1 on lock washers under American National Standards Committee B27. As of March 16, 1972, Subcommittees I and 2 became Subcommittees 22 and 21, respectively, of American National Standards Committee B 18. 2 As of
20、April l, 1966, Subcommittee 3 was redesignated Subcommittee 6; Subcommittee 9 was redesignated Subcommittee 3, and Subcommittee 27 was redesignated Subcommittee 13 of American National Standards Committee Bl8. iii SAE Standard 1773, Conical Washers. It was agreed that the proposal should be extended
21、 to include tapping screw sems. Consequently, additional meetings of the subcommit tee were held at which new drafts incorporating data for these products were reviewed and further changes and corrections were recommended. On February 15, 1963, a formal proposal was circulated for comment to Subcomm
22、ittees 3, 9, and 27 of the B 18 Committee, and Subcommittees 1 and 2 of the B27 Committee. On November 1963, a revised draft incorporating resolutions to the comments received and additional refinements was letter balloted to Sectional Committees B 18 and B27. The resulting comments and disapprovals
23、 were resolved at a meeting of Sectional Committee B 18 on June 4, 1964, and by circulation of the recommended dispositions to Sectional Committee B27 on February 12, 1965. Subsequent to approval by the sponsor and the American Standards Association, the document was formally designated an American
24、Standard, ASA B18.l3-1965, on September 29, 1965. Over the next 18 years attempts were made to update and refine the document. However, due to extended vacancies in the chairmanship and continual shifts in membership of Subcommittee 13, none of these efforts proved successful and the standard was re
25、affirmed for three review periods. At the December 5, 1984, meeting of Subcommittee 13, it was agreed the standard should be revised to incorporate those changes necessary to bring it into agreement with the latest versions of the referenced B 18 document covering the screw and washer components and
26、 for possible additional refinements. Recommendations for changes were reviewed and discussed further at a held on May 18, 1985, and task groups were established to prepare detailed proposals relative to specific product lines. A proposed revision was drafted that relegated the coverage for round an
27、d truss head sems and Type A and Type C tapping screw sems to appendices under “Not recommended for new design“ status. The revision included dimensional coverage for smaller sizes where applicable, changes to the helical spring lock washer sections and hardness, plus other technical and editorial u
28、pdating previously accepted. This proposal was reviewed at the December 3, 1985, meeting of Subcommittee 13. Numerous editorial refinements were considered and adopted. A formal proposal dated February 1986 was circulated to Subcommittees 3, 6, 13, 21, and 22 of the B 18 Committee. A revised proposa
29、l incorporating resolutions to the comments received was given letter ballot approval by Standards Committee B 18 in March 1987. Following its acceptance by ASME and the American National Standards Institute, this revision was granted recognition as an American National Standard on January 12, 1996.
30、 iv ASME STANDARDS COMMITTEE 818 Standardization of Bolts, Nuts, Rivets, Screws, Washers, and Similar Fasteners (The following is the roster of the Committee at the time of approval of this Standard.) OFFICERS K. E. McCullough, Chair D. A. Clever, Vice Chair E. Schwartz, Vice Chair A. M. Nickles, Se
31、cretary COMMITTEE PERSONNEL J. C. Akins, Safety Socket Screw Corp. J. B. Belford, Lawson Products, Inc. D. J. Broomfield, Illinois Tool Works, Inc. J. A. Buda, SPS Technologies R. M. Byrne, Trade Association Management, Inc. A. P. Cockman, Ford Motor Co. A. C. Dicola, Wrought Washer Manufacturing, I
32、nc. B. A. Dusina, Federal Screw Works H. W. Ellison, Consultant G. A. Gobb, Consultant R. J. Harrington, Spiro! International Corp. A. Herskovitz, U.S. Army A. C. Hood, ACH Technologies F. W. Kern, Society of Automotive Engineers W. H. Kopke, ITW Shakeproof Industrial Products P. D. Korsmo, Consulta
33、nt J. G. langenstein, Caterpillar, Inc. M. Levinson, ITW Shakeproof Industrial Products D. J. Miley, Caterpillar, Inc. M. D. Prasad, General Motors Corp. W. Schevey, BGM Fastener Co., Inc. R. M. Serabin, Bowman Distribution R. D. Strong, General Motors Corp. J. F. Sullivan, Accurate Fasteners, Inc.
34、R. l. Tennis, Caterpillar, Inc. S. W. Vass, Lake Erie Screw Corp./IFI R. G. Wever, BEl School of Engineering, Fairfield University C. J. Wilson, Industrial Fasteners Institute R. B. Wright, Wright Tool Co. J. G. Zeratsky, National Rivet ANSI, 11 West 42nd Street, New York, NY 10036-8002; ASTM, 100 B
35、arr Harbor Drive, West Conshohocken, PA 19428-2959; ASME, 22 Law Drive, Box 2300, Fairfield, NJ 07007-2300, (800) 843-2763. ASME 818.13-1996 - SEMS (Inch Series) (d) The inclusion of dimensional data in this Standard is not intended to imply that all of the products described herein are stock produc
36、tion items. Consumers should consult with suppliers concerning the availability of products. 1.2 Use and Application The sems covered by this Standard are general pur pose fasteners intended for mass production and other assembly operations where speed and convenience are paramount factors. Further
37、attributes of the various washers, recognized herein, are given in detail for each type of sems. 1.3 Types of Sems Included in these specifications are sems comprised of the following types of screws and washers. (a) Helical Spring Lock Washers ( 1) socket head cap screws (see Table 1) (2) hex cap s
38、crews (see Table 2) ( 3) machine screws (see Tables 2 and 3) (4) tapping screws (see Tables 2 and 3) (b) Tooth Lock Washers ( 1) machine screws (see Tables 4 and 5) (2) tapping screws (see Tables 4 and 5) ( 3) hex cap screws (see Tables 4 and 5) (c) Conical Spring Washers ( 1) hex cap screws (see Ta
39、ble 6) (2) machine screws (see Table 6) ( 3) tapping screws (see Table 6) (d) Plain Washers ( 1) machine screws (see Table 7) (2) tapping screws (see Table 7) ( 3) hex cap screws (see Table 7) (e) Products having washers of styles and shapes not shown in this Standard may be considered sems; however
40、, these products must be covered by the purchas ers drawing or standard. ASME 818.13-1996 1.4 Screw Heads 1.4.1 Head Styles. The head styles to the various types of sems shall be as in the illustrations and designated in the tables for each Where the slotted head sems are should be understood that t
41、his Standard also to the corresponding cross-recessed head sems. Round Head. In of the superior slot-characteristics of pan head screws over round head screws and the overlap in dimensions of pan heads and round it is recommended that pan head sems be used in new wherever pm;sltle, be substituted in
42、 existing designs. To expedite elimination of the necessity for perpetuating stocks of finished products and tooling, it should be rec:oQ:m:iea that the transition period manufacturers may, when it is agreeable to the purchasers, substitute pan head sems where round head sems have been specified. Di
43、mensions applicable to washers used for round head sems are documented for reference purposes in ces B through D. Truss Head. In the interest of simplifica-. ,VF“L-“F that the truss head is an mtlten:ntty weak sems incorporating this head style are not recommended for use in new Dimensions to washer
44、s used for truss head sems are documented for reference purposes in Appendices B D. Dimensions All dimensions in this Standard are given in inches unless stated otherwise. 1 where specified, shall be at the discretion of the manufacturer unless otherwise agreed upon by the manufacturer and the purch
45、aser. 1.7 The manufacturer shall not be held responsible for malfunctions of product determined to be due to plating or other modifications when such plating or modification is not accomplished under his control or direction. 1.8 Terminology For definitions of tenns relating to fasteners or compo ne
46、nt features thereof used in this Standard, refer to 2 SCREW AND WASHER ASSEMBLIES SEMS (INCH SERIES) ASME B 18.12, Glossary of Terms for Mechanical Fasteners. 1.9 To promote in commu-nications relating to conforming to this Stan-dard, it is recommended that sems be designated in accordance with the
47、following data, preferably in the sequence shown: nominal size (number, fraction, or decimal threads per inch; nominal length (fraction or decimal equivalent); point (tapping screw type or header point for machine screws); product name, including screw type, head style, and driving provision, and wa
48、sher type and/or series where required; material; and protective finish, if required. See examples below. EXAMPLES: (I) 1/4-14 x 11/4 Type AB, Slotted Pan Head Tapping Screw and Wide Plain Washer Sems, Steel, Zinc Plated (2) 6-32 x :Y4 Type lA Cross-Recessed Pan Head Machine Screw and Type H Regular
49、 Conical Spring Washer Sems, Steel (3) .375-16 x 1.50 Header Point, Hex Head Machine Screw and External Tooth Lock Washer Sems, Steel, Phosphate Coated (4) 8-32 x 1/2 Type T Hex Head Tapping Screw and Helical Spring Lock Washer Sems, Steel 1.10 lot For all inspections referenced in this Standard, the sems lot shall consist of screws of one type, grade, washer styie, finish, and size fabricated by the same production process from the same heat number of metal as provided by the metal manufacturer and submitted for inspection and testing at the same time. 1.11 Quality Assurance
