1、BS ISO 15872:2017Aerospace UNJ threads GaugingBSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06BS ISO 15872:2017 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 15872:2017. It supersedes BS ISO 15872:2002 which is withdrawn.The U
2、K participation in its preparation was entrusted to Technical Committee ACE/12, Aerospace fasteners and fastening systems.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a c
3、ontract. Users are responsible for its correct application. The British Standards Institution 2017.Published by BSI Standards Limited 2017ISBN 978 0 580 93598 5 ICS 49.030.10 Compliance with a British Standard cannot confer immunity from legal obligations.This British Standard was published under th
4、e authority of the Standards Policy and Strategy Committee on 31 March 2017.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dBS ISO 15872:2017 ISO 2017Aerospace UNJ threads GaugingAronautique et espace Filetage UNJ Vrification par calibresINTERNATIONAL STANDARDISO15872Second
5、 edition2017-03Reference numberISO 15872:2017(E)BS ISO 15872:2017ISO 15872:2017(E)ii ISO 2017 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2017, Published in SwitzerlandAll rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any
6、form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCh. de Blandon
7、net 8 CP 401CH-1214 Vernier, Geneva, SwitzerlandTel. +41 22 749 01 11Fax +41 22 749 09 47copyrightiso.orgwww.iso.orgBS ISO 15872:2017ISO 15872:2017(E)Foreword iv1 Scope . 12 Normative references 13 Terms, definitions, symbols and abbreviated terms . 13.1 Terms and definitions . 13.2 Symbols and abbr
8、eviated terms. 24 Types of gauges 34.1 Gauges and setting plugs for external threaded products . 34.2 Gauges for internal threaded products 35 Reference temperature 36 Function, design and use of gauges . 46.1 Gauges for external threads . 46.1.1 Virtual pitch diameter indicating thread gauges . 46.
9、1.2 Solid or adjustable GO screw ring gauges 46.1.3 Simple pitch diameter indicating thread gauges 46.1.4 Major diameter gauges . 56.1.5 Minor diameter gauges. 56.1.6 Optical comparator checks 56.2 Gauging for internal threads . 56.2.1 GO screw plug gauges 56.2.2 NOT GO screw plug gauges . 56.2.3 Mi
10、nor diameter gauges. 56.2.4 Virtual pitch diameter indicating thread gauges . 56.2.5 Simple pitch diameter indicating thread gauges 67 Setting of gauges . 67.1 Setting gauges for external threads 67.2 Setting ring gauge for indication thread gauges 68 Gauging of threads 68.1 General . 68.2 Internal
11、threads evaluation 7Bibliography .22 ISO 2017 All rights reserved iiiContents PageBS ISO 15872:2017ISO 15872:2017(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standar
12、ds is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take
13、 part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In part
14、icular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).Attention is drawn to the possibility that some of the elements o
15、f this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see
16、 www .iso .org/ patents).Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement.For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and expressions related to conformity assessment, as well
17、as information about ISOs adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following URL: www .iso .org/ iso/ foreword .html.This document was prepared by ISO/TC 20, Aircraft and space vehicles, Subcommittee SC 4, Aerospace fastener systems.
18、This second edition cancels and replaces the first edition (ISO 15872:2002), which has been technically revised and includes the following changes: unused symbols have beenremoved from Table 1: WGO, WNG, Z1, ZPL, and ZR. Figures have been changed to align with 8.1. Normative references have been upd
19、ated. Terminology has been updated. The document has been editorially revised.iv ISO 2017 All rights reservedBS ISO 15872:2017INTERNATIONAL STANDARD ISO 15872:2017(E)Aerospace UNJ threads Gauging1 ScopeThis document provides methods for the gauging of ISO UNJ threads complying with ISO 3161.Other me
20、thods of ensuring that the product is within the specified limits can be used, provided that correlation with the specified gauges is established.2 Normative referencesThe following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this
21、 document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 1, Geometrical product specifications (GPS) Standard reference temperature for the specification of geometrical and dimensiona
22、l propertiesISO 3161, Aerospace UNJ threads General requirements and limit dimensions3 Terms, definitions, symbols and abbreviated terms3.1 Terms and definitionsFor the purposes of this document, the terms and definitions given in ISO 5408 and the following apply.ISO and IEC maintain terminological
23、databases for use in standardization at the following addresses: IEC Electropedia: available at h t t p :/ www .electropedia .org/ ISO Online browsing platform: available at h t t p :/ www .iso .org/ obp3.1.1best wire sizecylinder or sphere which has a radius so that it will contact the thread flank
24、s at the pitch cylinder intersectionNote 1 to entry: The radius of the best wire or sphere is theoretically equal to 0,288 68P.3.1.2indicating gaugedevice having contacts which will precisely compare the size of a work piece thread to a setting standard of known dimensionsNote 1 to entry: The value
25、for the indicated characteristic thus established is the dimensional value attributed to the work piece. An indicating gauge can have contacts designed to measure any thread characteristic. This document specifies the characteristics and designs for ISO UNJ threads.3.1.3simple pitch diameterdiameter
26、 of an imaginary cylinder intersecting an actual thread over the width of one groove where that width is equal to one half of the basic pitch ISO 2017 All rights reserved 1BS ISO 15872:2017ISO 15872:2017(E)3.1.4virtual pitch diameterpitch diameter of the smallest (for external threads) or largest (f
27、or internal threads) perfect thread form with GO gauge profile which can engage the product threads for a distance equal to the GO gauge thread engagement3.2 Symbols and abbreviated termsSee Table 1.Table 1 Symbols, abbreviated terms and definitionsSymbol or abbreviated termDefinitionSymbol or abbre
28、viated termDefinitionD1Basic minor diameter of the internal thread of a workpieceT1/2Tolerance for each flank angle of a profile with complete flanksd2Basic pitch diameter of the external thread of a workpieceT2/2Tolerance for each flank angle of a profile with truncated flanksesFundamental deviatio
29、n of the exter-nal thread of a workpieceTCPTolerance on the pitch diameter of GO and NOT GO screw check plugs, wear check plugs and setting plugsEIFundamental deviation of the inter-nal thread of a workpieceTdTolerance for the major diameter of the external thread of a workpieceHHeight of the triang
30、le of a thread profileTd2Tolerance for the pitch diameter of the external thread of a workpieceH1Tolerance for the diameter of plain plug gaugesTd3Tolerance for the minor diameter of the external thread of a workpieceHPTolerance on the size of check plug gauges for plain calliper gaugesTD1Tolerance
31、for the minor diameter of the internal thread of a workpiece(LSL) Lower specification limit TPPitch tolerancem Distance between the middle of the tolerance zones TR of a screw ring gauge and TCP of a GO check plug TD2Tolerance for the pitch diameter of the internal thread of a workpiece(USL) Upper s
32、pecification limit TPLTolerance for the pitch diameter of GO and NOT GO screw plug gaugesP Pitch TRTolerance for the pitch diameter of GO and NOT GO screw ring gauges2 ISO 2017 All rights reservedBS ISO 15872:2017ISO 15872:2017(E)4 Types of gauges4.1 Gauges and setting plugs for external threaded pr
33、oductsThe function, design and use of gauges and setting plugs for external threads are explained in the following subclauses.Gauge type Subclausea) GO screw ring gauges 6.1.2b) Setting plug for adjustable GO screw ring and indicating thread gauges 7.1.1c) Virtual pitch diameter indicating thread ga
34、uges 6.1.1d) Simple pitch diameter indicating thread gauges 6.1.3e) Flat contact gauges for major diameter 6.1.4f) Point contact indicating thread gauges for minor diameter 6.1.5g) Optical comparator for root radius and minor diameter 6.1.64.2 Gauges for internal threaded productsThe function, desig
35、n and use of gauges for internal threads are explained in the following subclauses.Gauge type Subclausea) GO screw plug gauges 6.2.1b) NOT GO screw plug gauges 6.2.2c) Plain gauges for minor diameter (plug gauge) 6.2.3.1d) GO full form screw plug gauges 6.2.3.2e) Virtual pitch diameter indicating th
36、read gauges 6.2.4f) Simple pitch diameter indicating thread gauges 6.2.5g) Setting ring gauge for indicating thread gauges (solid type) 7.25 Reference temperatureIn accordance with ISO 1, the dimensions of the gauge and the product shall be checked at the temperature of 20 C.If the product and the g
37、auge have the same coefficients of linear expansion, the temperature may deviate from 20 C, provided the temperature of the product and the gauge are the same.If the product and the gauge have different coefficients of linear expansion, the temperature of both, at the time of gauging, shall be:a) 20
38、 C 2 C for sizes 1,000 UNJ and smaller;b) 20 C 1 C for larger threads. ISO 2017 All rights reserved 3BS ISO 15872:2017ISO 15872:2017(E)6 Function, design and use of gauges6.1 Gauges for external threads6.1.1 Virtual pitch diameter indicating thread gauges6.1.1.1 It measures, on two or three segments
39、 or rolls, the maximum material virtual pitch diameter taking into account variations of form such as pitch variation, helix and flank variations, roundness and taper which produces an enlargement of the virtual pitch diameter. In addition, virtual pitch diameter control ensures the flank angle cont
40、act is sufficient to ensure that the root radius does not exceed the maximum limit. Measurement of virtual pitch diameter with indicating gauges shall be obtained to calculate virtual minus simple pitch diameter differential unless the simple pitch diameter limits, gauged in accordance with 6.1.3, a
41、re within the limits defined by the maximum pitch diameter and the form variation limits in ISO 3161.6.1.1.2 Indicating gauges have two or three contacts at 180 or 120, respectively. Gauges with segments or rolls are designed with the length of the GO virtual maximum material gauging elements equal
42、to the GO ring gauge length equal to nine pitches (P) or the basic major diameter of the thread, whichever is the smallest. For configuration and profile requirements, see Figure 1.6.1.1.3 The minor diameter of the GO virtual maximum material thread segments and the diameter of the circle surrounded
43、 by the roll cluster of GO virtual maximum material rolls shall be equal to the pitch diameter of the product minus 0,375H, less the TPLvalue in Table 2 minus tolerance when assembled in the gauge frame. This corresponds to a flat width of 0,312 5P on the minor crest for the thread. The crest shall
44、be flat in an axial plane and parallel to the axis of the segments or rolls.6.1.1.4 The major diameter of the GO virtual maximum material segments and the root of the GO virtual maximum material rolls shall be cleared beyond a 0,125P flat either by an extension of the flanks of the thread toward a s
45、harp vee or by an undercut no greater than 0,125P maximum width and approximately central. The root clearance shall be such that the major diameter of the full form section of the thread setting plug gauge is cleared after the assembled gauge has been properly set to size.6.1.1.5 The pitch diameter
46、cylinder axis of threaded segments and rolls shall be straight within the diameter tolerance zone equal to TPLspecified in Table 2. The half-angle variations in the segment or roll thread shall be within the limits specified in Table 3. For the pitch variations, see Table 4.6.1.2 Solid or adjustable
47、 GO screw ring gaugesTo ensure the ease of assembly of product threads and conformance to the maximum material virtual pitch diameter limits, solid or adjustable, GO screw ring gauges with thread form in accordance with Figure 1 and setting gauges in accordance with 7.1.1 may be used. Solid GO screw
48、 ring gauges shall not be permitted to exceed the product thread dimensional limits. The gauge thickness/length shall be standardized (see 6.1.1.2). Details on adjustable GO thread ring gauges and truncated setting plugs may be obtained from ASME B1.2.6.1.3 Simple pitch diameter indicating thread ga
49、ugesThe simple pitch diameter indicating gauge with cone and vee rolls or segments or rolls with best wire size radius is applied to ensure that the pitch diameter is greater than the minimum limit. The indicators are set to the GO threaded setting plug gauge. Readings indicate the position of the pitch diameter and the minimum measurement shall be no less than the minimum pitch diameter limit. The minimum measured pitch diameter shall be within the ISO 3161 form variation limit compared to the virtua
