1、AN AMERICAN NATIONAL STANDARDASME B18.31.2-2008Continuous and Double-End Studs (Inch Series)Copyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-ASME B18.31.2-2008Continuous andDouble-End Studs(Inch Se
2、ries)AN AMERICAN NATIONAL STANDARDCopyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-Date of Issuance: November 24, 2008This Standard will be revised when the Society approves the issuance of a new e
3、dition. There willbe no addenda issued to this edition.ASME issues written replies to inquiries concerning interpretations of technical aspects of thisStandard. Periodically, certain actions of the ASME B18 Committee may be published as Cases. Casesand interpretations are published on the ASME Web s
4、ite under the Committee Pages athttp:/cstools.asme.org as they are issued.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 NationalStandards. The Standards Committee t
5、hat approved the code or standard was balanced to assure that individuals fromcompetent and concerned interests have had an opportunity to participate. The proposed code or standard was madeavailable for public review and comment that provides an opportunity for additional public input from industry
6、, academia,regulatory 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 anyitems mentioned in this docum
7、ent, and does not undertake to insure anyone utilizing a standard against liability forinfringement of any applicable letters patent, nor assume any such liability. Users of a code or standard are expresslyadvised that determination of the validity of any such patent rights, and the risk of infringe
8、ment of such rights, isentirely their own responsibility.Participation by federal agency representative(s) or person(s) affiliated with industry is not to be interpreted asgovernment or industry endorsement of this code or standard.ASME accepts responsibility for only those interpretations of this d
9、ocument issued in accordance with the establishedASME procedures and policies, which precludes the issuance of interpretations by individuals.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.Th
10、e American Society of Mechanical EngineersThree Park Avenue, New York, NY 10016-5990Copyright 2008 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll rights reservedPrinted in U.S.A.Copyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permit
11、ted without license from IHS-,-,-CONTENTSForeword ivCommittee Roster . vCorrespondence With the B18 Committee vi1 Introduction 12 Comparison With ISO Documents 13 Referenced Standards . 14 Terminology 15 Dimensions . 16 Body Diameter 37 Length . 38 Points 39 Thread Length 310 Screw Threads 311 Mater
12、ials and Mechanical Properties . 712 Identification Symbols. 713 Finish 714 Workmanship . 715 Straightness 716 Inspection and Quality Assurance 717 Dimensional Conformance . 718 Clearance Holes. 819 Designation. 8Tables1 Dimensions for Continuous Thread Studs 22 Dimensions for Clamping Type Studs 43
13、 Dimensions for Tap End Studs (1.5D Engagement) 54 Body Diameters for Double End Studs . 65 Length Tolerances for Studs 7Mandatory AppendixI Stud Straightness, Referee Gage, and Gaging Procedures 9iiiCopyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction o
14、r networking permitted without license from IHS-,-,-FOREWORDASME Standards Committee B18 for the Standardization of Bolts, Nuts, Rivets, Screws, Washers,and Similar Fasteners (formerly American National Standards Committee B18) was organizedin March 1922 as Sectional Committee B18 under the aegis of
15、 the American Engineering StandardsCommittee (later the American Standards Association, then the United States of AmericaStandards Institute, and, as of October 6, 1969, the American National Standards Institute, Inc.)with the Society of Automotive Engineers and the American Society of Mechanical En
16、gineers asjoint sponsors.In 1995, the SAE Ship Systems and Equipment Committee that was preparing fastener partstandards for the shipbuilding industry asked ASME Committee B18 if there was an interest indeveloping dimensional standards for studs. At the December 1995 meeting of B18 in Atlanta,it was
17、 reported that a survey by ASME showed considerable interest in establishing a subcommit-tee to develop stud standards, and 11 representatives indicated their willingness to serve on asubcommittee. Subcommittee 31 was established, and draft SAE inch and metric stud standardswere distributed for revi
18、ew.The first meeting of Subcommittee 31 on studs was held in April 1996, in conjunction withthe ASME B18 meetings in Chicago. Existing stud standards (IFI 136, Studs and Bolts, and IFI528, Metric Studs and Bolts) were compared with the draft SAE standards J2271, Part Standardfor Studs Continuous and
19、 Double End (Inch Series), and J2271M, Part Standard for Studs Continuous and Double End (Metric). The Subcommittee then identified the configurations tobe developed along with thread sizes and diameters to be covered. It was determined to developboth inch and metric standards covering both continuo
20、usly threaded and double ended studs.A decision to develop the metric standard first was unanimously passed.As the metric standard B18.31.1M was developed, little effort was devoted to the inch standarduntil 2005. In April 2005, the Subcommittee developed basic requirements for the inch studs thatwe
21、re similar to the metric studs, with the addition of interference-fit studs using ASME B1.12threads. A draft was reviewed at the November 2006 meeting with a number of format changessuggested. How to define the nominal length for tap end studs was discussed, and a motionwas approved to identify the
22、nominal length as the overall length rather than the protrusionlength when installed as used in ASME B18.31.1M per ISO 225 requirements.In November 2006, the Subcommittee decided that diameters from14in. to 4 in. would becovered although at the previous meeting it had been agreed to cover diameters
23、down to SizeNo. 0. The nominal length for tap end studs was again revisited without a consensus beingreached. At the April 2007 meeting, examples of both methods of identifying the nominal lengthof tap studs were reviewed, and it was determined to use the overall length as the nominal lengthas this
24、had been the past convention for inch studs in the United States.A draft was balloted prior to the November 2007 meeting and several disapprovals wereresolved at the meeting. It was agreed that the maximum nut end thread length would be deletedin favor of a total thread length to the last scratch, w
25、hich would be the minimum thread lengthplus five thread pitches. As a result, thread gaging is simplified without affecting the overallsuitability of the studs.A reconsideration draft was balloted prior to the April 2008 meeting. The only disapprovalwas withdrawn prior to the meeting, and the Subcom
26、mittee approved several minor editorialcorrections at the meeting.This edition was approved by the American National Standards Institute on August 4, 2008.ivCopyright ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from
27、 IHS-,-,-ASME B18 COMMITTEEStandardization 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.)STANDARDS COMMITTEE OFFICERSD. A. Clever, ChairR. D. Strong, Vice ChairR. L. Crane, SecretarySTANDARDS COMMI
28、TTEE PERSONNELV. Cartina, Continental-AeroD. A. Clever, Deere however, theyshould not contain proprietary names or information.Requests that are not in this format may be rewritten in the appropriate format by the Committeeprior to being answered, which may inadvertently change the intent of the ori
29、ginal request.ASME procedures provide for reconsideration of any interpretation when or if additionalinformation that might affect an interpretation is available. Further, persons aggrieved by aninterpretation may appeal to the cognizant ASME Committee or Subcommittee. ASME does not“approve,” “certi
30、fy,” “rate,” or “endorse” any item, construction, proprietary device, or activity.Attending Committee Meetings. The B18 Standards Committee regularly holds meetings, whichare open to the public. Persons wishing to attend any meeting should contact the Secretary ofthe B18 Standards Committee.viCopyri
31、ght ASME International Provided by IHS under license with ASME Not for ResaleNo reproduction or networking permitted without license from IHS-,-,-ASME B18.31.2-2008CONTINUOUS AND DOUBLE-END STUDS (INCH SERIES)1 INTRODUCTION1.1 Scope1.1.1 This Standard covers the complete dimen-sional and general dat
32、a for continuous thread and dou-ble-end inch-dimensioned studs recognized asAmerican National Standard. The following configura-tions are covered:continuous thread stud: studs that are threaded over theircomplete length.double-end stud (clamping type identical ends): studswith screw threads of the s
33、ame length and configurationon each end. This type of stud serves the function ofclamping two bodies together with a nut on each end.double-end stud (tap end type): a stud designed to beinstalled in a tapped hole and usually with differentthreaded lengths on each end. For the tap end of thestuds, bo
34、th regular unified threads and interference-fitthreads are covered.Double-end studs of the following body diametersare covered:(a) reduced diameter body (see para. 6.1 fordimensions)(b) full body (see para. 6.2 for dimensions)1.1.2 The inclusion of dimensional data in thisStandard is not intended to
35、 imply that all productsdescribed are stock production items. Consumers shouldconsult with suppliers concerning availability ofproducts.2 COMPARISON WITH ISO DOCUMENTSInch-dimensioned stud standards have not beenissued by ISO.3 REFERENCED STANDARDSThe following is a list iof publications referenced
36、inthsi Standard. Unless otherwise specified, the referenceshall be to the most recent issue at the time of orderplacement.ASME B1.1, Unified Inch Screw Threads (UN and UNRThread Form)ASME B1.3M, Screw Thread Gaging Systems forDimensional Acceptability Inch and Metric ScrewThreads (UN, UNR, UNJ, M, a
37、nd MJ)1ASME B1.12, Class 5 Interference-Fit ThreadASME B18.2.8, Clearance Holes for Bolts, Screws, andStudsASME B18.12, Glossary of Terms for MechanicalFastenersASME B18.18.2, Inspection and Quality Assurance forHigh-Volume Machine Assembly FastenersASME B18.24, Part Identifying Number (PIN) CodeSys
38、tem Standard for B18 Fastener ProductsASME Y14.5M, Dimensioning and TolerancingPublisher: The American Society of MechanicalEngineers (ASME), Three Park Avenue, New York,NY 10016-5990; Order Department: 22 Law Drive,P.O. Box 2300, Fairfield, NJ 07007-2300ASTM A 354, Quenched and Tempered Alloy Steel
39、 Bolts,Studs, and Other Externally Threaded FastenersASTM A 380, Standard Practice for Cleaning, Descaling,and Passivation of Stainless Steel Parts, Equipment,and SystemsASTM A 449, Quenched and Tempered Steel Boltsand StudsASTM F 468, Nonferrous Bolts, Hex Cap Screws, andStuds for General UseASTM F
40、 593, Stainless Steel Bolts, Hex Cap Screws,and StudsASTM F 788/F 788M, Surface Discontinuities of Bolts,Screws, and Studs, Inch and Metric SeriesASTM F 1941, Electrodeposited Coatings on ThreadedFasteners Unified Inch Screw Threads (UN/UNR)Publisher: ASTM International (ASTM), 100 Barr HarborDrive,
41、 P.O. Box C700, West Conshohocken, PA19428-2959SAE J429, Mechanical and Material Requirements forExternally Threaded FastenersPublisher: Society of Automotive Engineers (SAE), 400Commonwealth Drive, Warrendale, PA 15096-00014 TERMINOLOGYFor definitions of terms relating to fasteners or fea-tures the
42、reof used in this Standard, refer to ASME B18.12.5 DIMENSIONS(a) All dimensions in this Standard are given ininches, and apply before coating, unless otherwise speci-fied. Table 1 contains the dimensions for continuousCopyright ASME International Provided by IHS under license with ASME Not for Resal
43、eNo reproduction or networking permitted without license from IHS-,-,-ASME B18.31.2-2008Table 1 Dimensions for Continuous Thread StudsU ULTDNote (1)Threads Per Inch Note (2) Umaxp 2 Thread Pitches p 2PNominal Diameter,Size D UNC UNF 8UN UNC Threads UNF Threads 8UN Threads140.2500 20 28 . . . 0.100 0
44、.071 . . .5160.3125 18 24 . . . 0.111 0.083 . . .380.3750 16 24 . . . 0.125 0.083 . . .7160.4375 14 20 . . . 0.143 0.100 . . .120.5000 13 20 . . . 0.154 0.100 . . .916Note (3) 0.5625 12 18 . . . 0.167 0.111 . . .580.6250 11 18 . . . 0.182 0.111 . . .340.7500 10 16 . . . 0.200 0.125 . . .780.8750 9 1
45、4 . . . 0.222 0.143 . . .1 1.0000 8 12 . . . 0.250 0.167 . . .1181.1250 7 12 8 0.286 0.167 0.2501141.2500 7 12 8 0.286 0.167 0.2501381.3750 6 12 8 0.333 0.167 0.2501121.5000 6 12 8 0.333 0.167 0.2501581.6250 . . . . . . 8 . . . . . . 0.2501341.7500 5 . . . 8 0.400 . . . 0.2501781.8750 . . . . . . 8
46、. . . . . . 0.2502 2.0000 412. . . 8 0.444 . . . 0.2502142.2500 412. . . 8 0.444 . . . 0.2502122.5000 4 . . . 8 0.500 . . . 0.2502342.7500 4 . . . 8 0.500 . . . 0.2503 3.0000 4 . . . 8 0.500 . . . 0.2503143.2500 4 . . . 8 0.500 . . . 0.2503123.5000 4 . . . 8 0.500 . . . 0.2503343.7500 4 . . . 8 0.50
47、0 . . . 0.2504 4.0000 4 . . . 8 0.500 . . . 0.250NOTES:(1) See section 8 for end requirements.(2) See section 7 for requirements on stud lengths.(3) Nonpreferred size; not recommended for new design due to limited availability.2Copyright ASME International Provided by IHS under license with ASME Not
48、 for ResaleNo reproduction or networking permitted without license from IHS-,-,-ASME B18.31.2-2008thread studs. Table 2 contains the thread length dimen-sions for double-end (clamping type) studs. Table 3 con-tains the thread length requirements for tap end studs.Table 4 contains the body diameters
49、for double-end(clamping type) studs and tap end studs.(b) Symbols specifying geometric characteristics arein accordance with ASME Y14.5M.6 BODY DIAMETERThe diameter of the body on studs that are notthreaded the full length shall be within the limits for DSspecified for the applicable configuration. Unless other-wise specifi
