1、 Collection of SANS standards in electronic format (PDF) 1. Copyright This standard is available to staff members of companies that have subscribed to the complete collection of SANS standards in accordance with a formal copyright agreement. This document may reside on a CENTRAL FILE SERVER or INTRA
2、NET SYSTEM only. Unless specific permission has been granted, this document MAY NOT be sent or given to staff members from other companies or organizations. Doing so would constitute a VIOLATION of SABS copyright rules. 2. Indemnity The South African Bureau of Standards accepts no liability for any
3、damage whatsoever than may result from the use of this material or the information contain therein, irrespective of the cause and quantum thereof. ICS 49.030.10 ISBN 0-626-15257-7 SANS 1700-2-21:2004 Edition 1 ISO 5855-1:1999 Edition 3 SOUTH AFRICAN NATIONAL STANDARD Fasteners Part 2: Screw threads
4、Section 21: Aerospace MJ threads General requirements This national standard is the identical implementation of ISO 5855-1:1999 and is adopted with the permission of the International Organization for Standardization. Published by Standards South Africa 1 dr lategan road groenkloof ! private bag x19
5、1 pretoria 0001 tel: 012 428 7911 fax: 012 344 1568 international code + 27 12 www.stansa.co.za Standards South Africa 2004 SANS 1700-2-21:2004 Edition 1 ISO 5855-1:1999 Edition 3 Table of changes Change No. Date Scope Abstract Specifies the general requirements for MJ threads used in aerospace cons
6、truction. Determines the basic triangular profile for MJ threads and gives a system for designating the diameter and pitch combinations. Keywords aerospace construction, fasteners, specifications. National foreword This South African standard was approved by National Committee StanSA TC 5120.01, Scr
7、ew threads and fasteners, in accordance with procedures of Standards South Africa, in compliance with annex 3 of the WTO/TBT agreement. AReference numberISO 5855-1:1999(E)INTERNATIONALSTANDARDISO5855-1Third edition1999-10-15Aerospace MJ threads Part 1:General requirementsAronautique et espace Fileta
8、ge MJ Partie 1: Exigences gnralesISO 5855-1:1999(E) ISO 1999All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronicor mechanical, including photocopying and microfilm, without permission in writing from the pu
9、blisher.International Organization for StandardizationCase postale 56 CH-1211 Genve 20 SwitzerlandInternet isoiso.chPrinted in SwitzerlandiiForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISOmember bodies). The work of preparin
10、g International Standards is normally carried out through ISO technicalcommittees. Each member body interested in a subject for which a technical committee has been established hasthe right to be represented on that committee. International organizations, governmental and non-governmental, inliaison
11、 with ISO, also take part in the work. ISO collaborates closely with the International ElectrotechnicalCommission (IEC) on all matters of electrotechnical standardization.International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.Draft International Stan
12、dards adopted by the technical committees are circulated to the member bodies for voting.Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote.International Standard ISO 5855-1 was prepared by Technical Committee ISO/TC 20, Aircraft and space
13、 vehicles,Subcommittee SC 4, Aerospace fastener systems.This third edition cancels and replaces the second edition (ISO 5855-1:1988), of which it constitutes a technicalrevision.ISO 5855 consists of the following parts, under the general title Aerospace MJ threads:Part 1: General requirementsPart 2:
14、 Limit dimensions for bolts and nutsPart 3: Limit dimensions for fittings for fluid systemsINTERNATIONAL STANDARD ISO ISO 5855-1:1999(E)1Aerospace MJ threads Part 1:General requirements1 ScopeThis part of ISO 5855 specifies the general requirements for MJ threads used in aerospace construction.It de
15、termines the basic triangular profile for this type of thread and gives a system for designating the diameter andpitch combinations. For all diameters 1,6 mm to 300 mm, it offers in the form of tables the basic dimensions andtolerances for a selection of diameter and pitch combinations. It also prov
16、ides the method of calculation for thedimensions and tolerances for any diameter and pitch combination not given in the tables, including threads with adiameter in excess of 300 mm.For limit dimensions for bolts and nuts of nominal diameter 1,6 mm to 39 mm, see ISO 5855-2. For limit dimensions forfi
17、ttings for fluid systems, see ISO 5855-3.2 Normative referenceThe following normative document contains provisions which, through reference in this text, constitute provisions of thispart of ISO 5855. For dated references, subsequent amendments to, or revisions of, any of these publications do notap
18、ply. However, parties to agreements based on this part of ISO 5855 are encouraged to investigate the possibility ofapplying the most recent edition of the normative document indicated below. For undated references, the latest editionof the normative document referred to applies. Members of ISO and I
19、EC maintain registers of currently validInternational Standards.ISO 965-1:1998, ISO general-purpose metric screw threads Tolerances Part 1: Principles and basic data.3 Term and definitionFor the purpose of this part of ISO 5855, the following term and definition apply.3.1basic profiletheoretical pro
20、file, in an axial plane, corresponding to the basic dimensions (without tolerances) of the thread, i.e.major diameter, pitch diameter and minor diameterSee Figure 1.4 Basic profile4.1 SymbolsSee Figure 1.ISO 5855-1:1999(E) ISO24.2 DimensionsSee Figure 1 and Table 1.Basic deviations shall be applied
21、to the basic dimensions.whereD is the basic major diameter of internal threadD2is the basic pitch diameter of internal threadD1is the basic minor diameter of internal threadd is the basic major diameter of external threadd2is the basic pitch diameter of external threadd1is the basic minor diameter o
22、f external threadH is the height of fundamental triangleP is the pitchaAxis of threadFigure 1 Basic profile ISOISO 5855-1:1999(E)3Table 1 DimensionsISO 5855-1:1999(E) ISO45 Position and form of limit profiles5.1 External threadsThe actual thread profile is located between the limit profiles shown in
23、 Figures 2 and 3.Within these limits, any continuous, non-reversing curve is permitted, provided that it comprises radii no less than0,150 11P.aPitch D PbBasic and maximum profilescBasic profiledMinimum profileFigure 2 Limit profiles for external threads (clearance may be nil) ISOISO 5855-1:1999(E)5
24、aPitch D PbBasic profilecMaximum profiledMinimum profileFigure 3 Limit profiles for external threads (systematic clearance)5.2 Internal threadsThe actual thread profile is located between the limit profiles shown in Figures 4 and 5.The form of the connection between the root (corresponding to diamet
25、er D3) and the thread flanks is not mandatory.The root is generally rounded beyond the nominal diameter. The radius is not specified.ISO 5855-1:1999(E) ISO6aPitch D PbBasic profilecMaximum profiledBasic and minimum profilesFigure 4 Limit profiles for internal threads (clearance may be nil)aPitch D P
26、bMaximum profilecMinimum profiledBasic profileFigure 5 Limit profiles for internal threads (systematic clearance) ISOISO 5855-1:1999(E)76 Tolerances6.1 Tolerances on diametersThe grades, positions and basic upper and lower (es and EI) tolerance deviations (see Figures 3 and 5) shall be asspecified i
27、n ISO 965-1.6.2 Tolerances on other parametersTolerances on pitch D P and on the half flank angle D a shall be determined from the formulae given in clause 10.Within the limits of the thread pitch diameter, and over the chosen length of measurement, the sum of the effects ofvariations in the pitch,
28、flank angle, helix, taper and circularity and all other variations affecting the form of the threadshall not exceed 0,5 times the tolerance on the pitch diameter. The following information is therefore given forinformation only.The thread pitch may vary by D P from the basic profile, but the total v
29、ariation between any two threads locatedwithin the length of engagement should not exceed D P.6.3 Provisions for coated threadsIn order to reduce the number of manufacturing and inspection tools, it is recommended that, where possible,standardized tolerance classes for threads (grade and position) a
30、s specified in ISO 965-1 be used.7 Limit dimensionsThe limit dimensions, shown in Figures 2 to 5, shall be determined from the formulae given in clause 10.8 Nominal diameter and pitch combinationsThe threads in 5.1 and 5.2 and indicated in Table 2 meet most requirements. If other diameter and pitchc
31、ombinations or threads larger than 300 mm in diameter are required, then these shall be calculated using theformulae in clause 10.9 Designation9.1 GeneralThe threads specified in this part of ISO 5855 are designated by:M, a letter identifying metric threads;J, a letter symbolizing the thread profile
32、;the nominal diameter pitch, expressed in millimetres;the tolerance class on pitch diameter, followed by the tolerance class on the major diameter or on the minordiameter1).1)If a single tolerance class is given, it refers to the pitch diameter d2or D2and the major diameter d or minor diameter D1.IS
33、O 5855-1:1999(E) ISO8EXAMPLE 1 An external MJ thread, of nominal diameter 6 mm, pitch 1 mm and tolerance classes 4h6h is designated asfollows:MJ6 1-4h6hEXAMPLE 2 An internal MJ thread, of nominal diameter 6 mm, pitch 1 mm and tolerance classes 4H5H is designated asfollows:MJ6 1-4H5H9.2 Special cases
34、MJ threads not specified in this part of ISO 5855 are special threads.They shall be calculated in accordance with clause 10 and designated byMJ, see 9.1;S, a letter symbolizing a special thread;all the information necessary to produce the thread.EXAMPLE 1 An external MJ thread, of nominal diameter 1
35、3 mm, pitch 1 mm and tolerance class 4h2)is designated asfollows:MJS13 1-4h13Major diameter d = 12,888 mm12,350Pitch diameter d2= 12,275 mm11,845Minor diameter d3= 11,709 mm0,18Root radius = 0,15 mmEXAMPLE 2 An internal MJ thread of nominal diameter 13 mm, pitch 1 mm and tolerance class 4H5H, is des
36、ignated asfollows:MJS13 1-4H5HMajor diameter D3max. = 13,244 mm12,450Pitch diameter D2= 12,350 mm12,216Minor diameter D1= 12,026 mm2)If a single tolerance class is given, it refers to the pitch diameter d2or D2and the major diameter d or minor diameter D1. ISOISO 5855-1:1999(E)99.3 Left-hand threads
37、In the case of left-hand threads, the designation given in 9.1 and 9.2 is followed by the letters LH (Left-Hand).9.3.1 GeneralEXAMPLE 1 MJ6 1-4h6h-LHEXAMPLE 2 MJ6 1-4H5H-LH9.3.2 Special casesEXAMPLE 1 MJS13 1-4h-LHEXAMPLE 2 MJS13 1-4H5H-LH10 Calculation formulae10.1 External threads (see Figures 2 a
38、nd 3)d max. = d - eses: in accordance with ISO 965-1d min. = d max. - TdTd: in accordance with ISO 965-1 or as defined by part designerd2max. = d2= d max. - 0,649 519P0,649 519P: see Table 1.d2min. = d2max. - Td2Td2: in accordance with ISO 965-1 or as defined by part designerd3max. = d3= d2max. - 0,
39、505 18P0,505 18P: see Table 1.d3min. = d2min. - 0,565 80P0,565 80P: see Table 1.D P = 0,4 Td2/1,732 1D a is such that tan (D a ) = 0,3 Td2/1,125PTables 3 and 4 give information for the limit dimensions for respectively 4h6h and 4g6g external threads.Table 5 gives information for the root radii for e
40、xternal threads.Table 6 gives information for the maximum permissible deviations on pitch (lead) and on half flank angle.ISO 5855-1:1999(E) ISO1010.2 Internal threads (see Figures 4 and 5)D1min. = D - 0,974 28P + EI0,974 28P: see Table 1.EI: in accordance with ISO 965-1D1max. = D1min. + TD1TD1: in a
41、ccordance with ISO 965-1 or as defined by part designerD2min. = D2= D - 0,649 519P + EI0,649 519P: see Table 1.D2max. = D2min. + TD2TD2: in accordance with ISO 965-1 or as defined by part designerD3max. = D2max. + 0,793 86P0,793 86P: see Table 1.D P = 0,4TD2/1,732 1D a is such that tan (D a ) = 0,3T
42、D2/1,125PTable 7 gives information for the limit dimensions for internal threads.Table 6 gives information for the maximum permissible deviations on pitch (lead) and on half flank angle. ISOISO 5855-1:1999(E)11Table 2 Nominal diameter and pitch combinationsDimensions in millimetresD PD PD PD PD PD P
43、D P1,6 0,35 17 139 262 285 3 140 6 220 31,8 0,35 17 1,5 39 36 38 4 145 2 220 42 0,4 18 139 462 485 6 145 3 220 62,2 0,45 18 1,5 40 1,5 64 1,5 88 1,5 145 4 225 32,5 0,35 18 240 264 290 1,5 145 6 225 42,5 0,45 18 2,5 40 36 39 2 150 2 225 63 0,35 20 142 1,5 64 490 3 150 3 230 33 0,5 20 1,5 42 264 69 4
44、150 4 230 43,5 0,35 20 242 365 1,5 90 6 150 6 230 63,5 0,6 20 2,5 42 46 295 2 155 3 235 34 0,5 22 142 4,5 65 39 3 155 4 235 44 0,7 22 1,5 45 1,5 65 495 4 155 6 235 64,5 0,5 22 245 268 1,5 95 6 160 3 240 34,5 0,75 22 2,5 45 36 2 100 2 160 4 240 45 0,5 24 145 468 3 100 3 160 6 240 65 0,8 24 1,5 45 4,5
45、 68 4 100 4 165 3 245 35,5 0,5 24 248 1,5 68 6 100 6 165 4 245 46 0,75 24 34 270 1,5 105 2 165 6 245 66 125 148 37 2 105 3 170 3 250 37 0,75 25 1,5 48 470 3 105 4 170 4 250 47 125 248 57 4 105 6 170 6 250 68 0,75 26 1,5 50 1,5 70 6 110 2 175 3 255 48 127 150 272 1,5 110 3 175 4 255 68 1,25 27 1,5 50
46、 37 2 110 4 175 6 260 49 0,75 27 252 1,5 72 3 110 6 180 3 260 69 127 35 272 4 115 2 180 4 265 49 1,25 28 152 37 6 115 3 180 6 265 610 0,75 28 1,5 52 475 1,5 115 4 185 3 270 410 128 252 57 2 115 6 185 4 270 610 1,25 30 155 1,5 75 3 120 2 185 6 275 410 1,5 30 1,5 55 275 4 120 3 190 3 275 611 0,75 30 2
47、55 376 1,5 120 4 190 4 280 411 130 35 47 3 120 6 190 6 280 611 1,25 30 3,5 56 1,5 76 4 125 2 195 3 285 411 1,5 32 1,5 56 276 6 125 3 195 4 285 612 132 256 378 1,5 125 4 195 6 290 412 1,25 33 1,5 56 47 2 125 6 200 3 290 612 1,5 33 256 5,5 78 3 130 2 200 4 295 412 1,75 33 358 1,5 80 1,5 130 3 200 6 295 614 133 3,5 58 280 2 130 4 205 3 300 414 1,25 35 1,5 58 38 3 130 6 205 4 300 614 1,5 35 258 480 4 135 2 205 614 236 1,5 60 1,5 80 6 135 3 210 315 13 260 282 1,5 135 4 210 415 1,5 36 36 38 2 135 6 210 616 136 460 482 3 140 2 215 316 1,5 38 1
