1、ASMEIANSI B18.3.5M-1986 3/17! 05 26 February 1987 SUPERSEDING ANSIIASME B18.3.5M-1983 20 October 1983 ACCEPTANCE NOTICE This non-Government document was adopted on 26 February 1987, and is approved for use by the DoD. the clearance required by existing regulations. Copies of the document are stocked
2、 by the DoD Single Stock Point, Naval Publications and Forms Center, Philadelphia, PA 19120-5099, for issue to DoD activities only. Contractors and Industry groups must obtain copies directly from: The American Society of Mechanical Engineers United Engineering Center, 345 E. 47th Street, New York,
3、NY 10017 or The American National Standards Institute, 1430 Broadway, New York, NY 10018. The indicated industry group has furnished Title of Document: Screw, Cap, Hexagon Socket, Flat Countersunk Head-Metric Document Number: ASMEIANSI 318.3.5M-1986 Date of Specific Issue Adopted: 25 September 1986
4、Releasing Industry Group: The American Society of Mechanical Engineer s NOTICE: When reaffirmation, amendment, revision, or cancellation of this standard is initially proposed, the industry group responsible for this standard shall inform the military coordinating activity of the proposed change and
5、 request participation. Custodians: Army - AR Navy - AS Air Force - 99 Military Coordinating Activity: Army - AR (Project 5305-1675) Review Activities: Army - AT, AV, EA, CR, MI NSA - NS DLA, IS L User Activities: Amy - ME Navy - MC, OS, SH Civil Agency Coordinating Activities: GSA - FSS AMSC N/A -1
6、 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Copyright ASME International Provided by IHS under license with ASMENot for ResaleNo reproduction or networking permitted without license from IHS-,-AN AMERICAN NATIONAL STANDARD Hexagon Socket Flat Countersunk Head C
7、ap Screws (Metric Series) ASMEIANSI BI 8.3.5M-1986 (REVISION OF ANWASME B18.3.5M-1983) Government Key Words: Screw, Cap, Hexagon Socket, Flat Countersunk Head - Metric SPONSORED AND PUBLISHED BY THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS United Engineering Center New York, N. Y. 1 O01 7 345 East 4
8、7th Street Copyright ASME International Provided by IHS under license with ASMENot for ResaleNo reproduction or networking permitted without license from IHS-,-Date of Issuance: February 28, 1987 This Standard will be revised when the Society approves the issuance of a new edition. There will be no
9、addenda or written interpretations of the requirements of this Standard issued to this Edition. This code or standard was developed under procedures accredited as meeting the criteria for American National Standards. The Consensus Committee that approved the code or standard was balanced to assure t
10、hat 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, regulatory agencies, and the public-at-larg
11、e. 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 does not undertake to insure anyone utiliz
12、ing a standard against liability for infringement of any applicable Letters Patent, por 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 such rights, is entirely their own respon
13、sibility. Participation by federal agency representative(s) or person(s) 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 accordance with governing ASME procedures an
14、d 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. Copyright O 1987 by THE AMERICAN SOCIETY OF MECHANICAL EN
15、GINEERS All Rights Reserved Printed in U.S.A. Copyright ASME International Provided by IHS under license with ASMENot for ResaleNo reproduction or networking permitted without license from IHS-,-FOREWORD (This Foreword is not part of ASMEIANSI B18.3.5M-1986.) American National Standards Committee B1
16、8 for the standardization of bolts, screws, nuts, rivets, and similar fasteners was organized in March 1922 as Sectional Committee B18 under the aegis of the American Engineering Standards Committee (later the American Standards Association, then the United States of America Standards Institute and,
17、 as of October 6, 1969, the American National Standards Institute) with the Society of Automo- tive Engineers and the American Society of Mechanical Engineers as joint sponsors. Subcommittee 9 was established in April of 1929 to undertake development and oversee maintenance of standards covering soc
18、ket head cap screws and set screws. In line with a gen- eral realignment of the subcommittee structure on April 1, 1966, Subcommittee 9 was redes- ignated Subcommittee 3. Over the intervening years this activity has produced several ver- sions of American National Standards coveringinch series socke
19、t cap, shoulder, and set screws bearing the B18.3 designation. At the December 4, 1974 meeting of American National Standards Committee B18, Sub- committee 3 was assigned the task of preparing standards for metric series socket screw products paralleling that contained in the latest ANSI BJ8.3 docum
20、ent. The Subcommittee was also instructed to continue coordination with the International Standards Organiza- tion, IS0 Technical Committee 2, and Working Group 3 under that activity and, to the ex- tent possible, keep the proposals for metric standards under development in conformance with agreemen
21、ts reached therein. Subsequent meetings of Subcommittee 3 held in February i975 and January 1976 re- sulted in general agreement on the following basic principles to be considered in developing the metric version of the standard. (u) To assure consumers continuity of performance integrity consistent
22、 with inch socket screw products, the metric standards should maintain the same quality levels as their inch counterparts. (b) To facilitate and expedite the processing, acceptance, and adoption of the metric ver- sions, proposals for the various product categories should be prepared as separate and
23、 com- plete product standards. (c) To promote understanding and assimilation during the transition to metric, the di- mensional symbols, designations, terminology, and basic formats of the metric standards should be kept similar to those used in the ANSI B18.3 document. There is no present or propos
24、ed IS0 document for hexagon socket flat countersunk head cap screws, and the work in ISO/TC2/WG3 is proceeding slowly. Three different proposals have been submitted to WG3 for consideration and a draft document combining the best features of these proposals was circulated to the industry and many us
25、ers. At the Subcom- mittee meeting of May 1982, it was voted to submit this draft, as modified, as a proposed standard. It is noted that these screws are functionally interchangeable with those recently adopted by the United Kingdom as BSI 4168-1982, with the exception of the class of thread fit, wi
26、th the U.S. document specifying class 4g6g in line with past practice. The document was modified to suit the ASME/ANSI format and was submitted for letter ballot vote to ASME Committee B18 and for public review. It was granted recognition as an American National Standard on April 8, 1983. . 111 Copy
27、right ASME International Provided by IHS under license with ASMENot for ResaleNo reproduction or networking permitted without license from IHS-,-ASME B38*3*5M 86 2575532 0015072 2 A periodic review of the standard, undertaken by the Subcommittee in 1985, resulted in agreement that the document shoul
28、d be revised to add corrosion-resistant steel and to incorporate by reference ASTM documents for the appropriate mechanical, chemical, and testing requirements for the hexagon socket flat countersunk head cap screw products. A proposal containing these changes, as well as editorial corrections, was
29、prepared and bal- loted by letter ballot to ASME Committee B18. Following approval by ASME, the proposal was submitted to the American National Standards Institute and designated an American National Standard on September 25, 1986. iv Copyright ASME International Provided by IHS under license with A
30、SMENot for ResaleNo reproduction or networking permitted without license from IHS-,- ASME B18*3*5M 86 W 2575512 0015073 LI ASME STANDARDS COMMITTEE BI8 Standardization of Bolts, Nuts, Rivets, Screws, Washers, and Similar Fasteners (The following is the roster of the Committee at the time of approval
31、 of this Standard.) OFFICERS J. B. Levy, Chairman H. W. Ellison, Vice Chairman E. Schwartz, Vice Chairman R. W. McGinnis, Secretary COMMITTEE PERSONNEL AMERICAN SOCIETY OF AGRICULTURAL ENGINEERS E. R. Friesth, Don E. Williams Co., Rock Island, Illinois AMERICAN SOCIETY OF MECHANICAL ENGINEERS A. R.
32、Machell, Webster, New York K. E. McCullough, SPS Technologies Inc., Jenkintown, Pennsylvania ENGINE MANUFACTURERS ASSOCIATION G. A. Russ, Cummins Engine Co., Columbus, Indiana FARM (b) Nominal size of screw; (c) Thread pitch, preceded by x ; 1 . Copyright ASME International Provided by IHS under lic
33、ense with ASMENot for ResaleNo reproduction or networking permitted without license from IHS-,-ASME/ANSI B18.3.5M-1986 (6) Nominal screw length, preceded by x ; (e) Product name. If desired, the product name may be abbreviated FCHS. u Material and property class. Alloy steel screws shall be supplied
34、 to property class 12.9 as specified in ASTM F 835M. For corrosion-resistant steel screws, the property class and material requirements shall be as specified in ASTM F 879M (see para. 3.1). (g) Protective finish, if required. Examples: B18.3.5M - 6 x 1 x 18 Socket Flat Countersunk Head Cap Screw, Nl
35、oy Steel Product Name or B18.3.5M - 8 x 1.25 x 20 FCHS; Corrosion-resistant Steel CI. Al-70 1.8 Part Numbering System For users who need a definitive part numbering sys- tem, one is suggested in Appendix II. 2 DIMENSIONAL CHARACTERISTICS . The following requirements supplement the dimen- sional data
36、 presented in Tables 1 A, lB, and 2 and shall apply to the respective features of screws. 2.1 Heads 2.1.1 Head Diameters. The maximum sharp val- ues listed under A in Table 1A are theoretical values, as it is not practical to make the edges of the head sharp. The maximum sharp value represents the e
37、xact diameter of a hole countersunk to exactly 90 deg., in which a screw having maximum head size will fit flush. 2.1.2 Head Height. The tabulated values for head height are given for reference only and are calculated to the maximum formulation. 2.1.3 Flushness Tolerance. The flushness-toler- ance i
38、s the distance the top surface of a screw having the minimum head size will be below the flush condi- tion in a hole countersunk exactly 90 deg. to the maxi- mum sharp dimension listed under A in Table IA. 2.1.4 Fillet. A fillet between the conical bearing surface of the head and the shank (body) of
39、 the screw is allowable above the maximum tabulated value for D within the value listed for F. 2 HEXAGON SOCKET FLAT COUNTERSUNK HEAD CAP SCREWS (METRIC SERIES) 2.2 Sockets 2.2.1 Socket Size. Sockets shall be nominal size J specified in Table 1A for the respective screw sizes and shall conform to th
40、e dimensions given in Table 2, as determined by gaging in accordance with para. 2.2.3. 2.2.2 Key Engagement. The key engagement depth shall conform to the minimum values specified for Tin Table lA, as determined by gaging in accor- dance with para. 2.2.3. 2.2.3 Socket Gaging. Acceptability of socket
41、s shall be determined by the use of the hexagon socket gages specified in Table 3A. The hexagon sockets shall allow the GO member of the gage to enter freely to the minimum key engagement depth. The NOT GO gage member shall be permitted to enter only to a depth equivalent to 7.5% of the nominal sock
42、et size. To determine the acceptability of sockets in plated products after plating, a GO gage identical in design and tolerances to that shown in Table 3A, except hav- ing a maximum width across flats dimension equal to the nominal socket size, shall be used. 2.2.4 Edge of Socket. The edge at the j
43、unction of the socket with the top of the head may be broken (rounded or chamfered) as depicted in Fig. 3, provid- ing the depth of chamfer or rounding does not violate the NOT GO gage penetration limit specified in para. 2.2.3. 2.2.5 Broached Sockets. For hexagon broached sockets at or near the max
44、imum size limit, the overcut resulting from drilling shall not exceed 20% of the length of any flat of the socket (see Fig. 2). 2.2.6 Socket True Position. The axis of thesocket shall be located at true position relative to the axis of the screw within a tolerance zone having a diameter equal to 3%
45、of the basic screw diameter or 0.26 mm, whichever is greater, for nominal screw sizes up to and including 12 mm; and equal to 6% of the basic screw diameter for sizes larger than 12 mm, regardless of feature size. 2.2.7 Wall Thickness. Wall thickness G may be controlled by using gaging shown in Appe
46、ndix IV, Fig. IV-1. 2.3 Length 2.3.1 Measurement. The length of hexagon socket flat countersunk head cap screws shall be measured parallel to the axis of the screw from the plane of the top of the head to the extreme end of the shank. Copyright ASME International Provided by IHS under license with A
47、SMENot for ResaleNo reproduction or networking permitted without license from IHS-,-Fbh- ness Toler- ance 0.30 0.30 0.35 0.35 0.40 0.50 0.60 0.70 0.80 1.00 Hexagon Key Socket Engage- Size ment Nom. Min. 2.0 1.1 2.5 1.5 3.0 1.9 4.0 2.2 5.0 3.0 6.0 3.6 8.0 4.3 10.0 4.7 10.0 4.8 12.0 5.6 HEXAGON SOCKET
48、 FLAT COUNTERSUNK HEAD CAP SCREWS (METRIC SERIES) ASME/ANSI B18.3.5M-1986 4 (Para. 2.4.4.2) Theoretical sharp Absolute minimum (Para. 2.4.4.1) 2.3. I +TI- ENSIONS OF METRIC CO JNTERSUNK SOCKET HEAD CAP SCREWS TABLE IA Din D A H IJIT F G M Head Diameter HeadHeight I I Nominal Size or Basic Screw Diar
49、netei Fillet Extension Above D Socket Wall Drill Allow. Theo- retical Sharp Max. 6.72 8.96 11.20 13.44 17.92 22.40 26.88 30.24 33.60 40.32 Iody Diameter Thread Pitch Absolute Min. 5.35 7.80 9.75 11.70 15.60 19.50 23.40 26.18 28.96 34.60 Refer- ence 1.86 2.48 3.10 3.72 4.96 6.20 7.44 8.1 2 8.80 10.16 Min. Max. Max. 0.3 0.4 0.5 0.6 0.8 0.9 1.2 1.5 1.5 1 .a 0.25 0.45 0.66 0.70 1.16 1.62 1.80 1.62 2.20 2.20 0.25 0.35 0.40 0.50 0.60 0.80 0.90 1 .o0 1 .o0 1.20 3 4
