1、BS 3643-2:2007ISO metric screw threadsPart 2: Specification for selected limits of sizeICS 21.040.10NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBRITISH STANDARDBS 3643-2:2007Incorporating Corrigendum No. 1BS 8487:2007+A1:2013Publishing and copyright informationThe BSI copyr
2、ight notice displayed in this document indicates when the document was last issued. The British Standards Institution 2014 Published by BSI Standards Limited 2014ISBN 978 0 580 86558 9The follow BSI references relate to the work on this standard: Committee reference FME/9 Draft for comment 07/301584
3、88 DCPublication historyFirst published June 1965Second edition, December 1966Third edition, December 1981Fourth edition, November 2007Amendments issued since publicationAmd. no. Date Text affectedC1 June 2014 See Foreword BSI 2007 iBS 3643-2:2007ContentsForeword ii1 Scope 12 Normative references 13
4、 Terms and definitions 14 Designation 25 Requirements 2AnnexesAnnex A (normative) Fundamental deviations, tolerances and limits of size for additional tolerance classes for aerospace use 39Bibliography 42List of tablesTable 1 ISO metric screw threads Limits and tolerances for finisheduncoated thread
5、s for normal length of engagement 3Table A.1 ISO metric screw threads Limits and tolerances for finished uncoated threads for normal length of engagement for aerospace use 40Summary of pagesThis document comprises a front cover, an insidefront cover, pagesiand ii, pages 1 to 42, an inside back cover
6、 and a back cover.BS 3643-2:2007 The British Standards Institution 2014 iBS 3643-2:2007ii BSI 2007ForewordPublishing informationThis part of BS 3643 is published by BSI and came into effect on 30 November 2007. It was prepared by Subcommittee SFTSE/1, Screws and fasteners technical specification com
7、mittee, under the authority of Technical Committee FME/9, Nuts, bolts and accessories. A listof organizations represented on this committee can be obtained on request to its secretary.SupersessionThis part of BS 3643 supersedes BS 3643-2:1981, which is withdrawn.Relationship with other publicationsB
8、S 3643 consists of the following parts: Part 1: Principles and basic data; Part 2: Specification for selected limits of size.Information about this documentThis part of BS 3643 has been revised to bring it up to date.Hazard warningsPresentational conventionsThe provisions of this standard are presen
9、ted in roman (i.e. upright) type. Its requirements are expressed in sentences in which the principal auxiliary verb is “shall”.Commentary, explanation and general informative material is presented in smaller italic type, and does not constitute a normative element.Contractual and legal consideration
10、sThis publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot conferimmunity from legal obligations.WARNING. Attention is drawn to the fact that, with the differentscrew thread for
11、ms available, there is the possibility of a mismatch,which is potentially hazardous. It is the responsibility of the designer of the end product toensure thatthis possibility is reduced to a minimum. For further information on mismatches of screw thread systems see PD 6494.BS 3643-2:2007ii BSI 2007F
12、orewordPublishing informationThis part of BS 3643 is published by BSI and came into effect on 30 November 2007. It was prepared by Subcommittee SFTSE/1, Screws and fasteners technical specification committee, under the authority of Technical Committee FME/9, Nuts, bolts and accessories. A listof org
13、anizations represented on this committee can be obtained on request to its secretary.SupersessionThis part of BS 3643 supersedes BS 3643-2:1981, which is withdrawn.Relationship with other publicationsBS 3643 consists of the following parts: Part 1: Principles and basic data; Part 2: Specification fo
14、r selected limits of size.Information about this documentThis part of BS 3643 has been revised to bring it up to date.Hazard warningsPresentational conventionsThe provisions of this standard are presented in roman (i.e. upright) type. Its requirements are expressed in sentences in which the principa
15、l auxiliary verb is “shall”.Commentary, explanation and general informative material is presented in smaller italic type, and does not constitute a normative element.Contractual and legal considerationsThis publication does not purport to include all the necessary provisions of a contract. Users are
16、 responsible for its correct application.Compliance with a British Standard cannot conferimmunity from legal obligations.WARNING. Attention is drawn to the fact that, with the differentscrew thread forms available, there is the possibility of a mismatch,which is potentially hazardous. It is the resp
17、onsibility of the designer of the end product toensure thatthis possibility is reduced to a minimum. For further information on mismatches of screw thread systems see PD 6494.BS 3643-2:2007ii BSI 2007ForewordPublishing informationThis part of BS 3643 is published by BSI and came into effect on 30 No
18、vember 2007. It was prepared by Subcommittee SFTSE/1, Screws and fasteners technical specification committee, under the authority of Technical Committee FME/9, Nuts, bolts and accessories. A listof organizations represented on this committee can be obtained on request to its secretary.SupersessionTh
19、is part of BS 3643 supersedes BS 3643-2:1981, which is withdrawn.Relationship with other publicationsBS 3643 consists of the following parts: Part 1: Principles and basic data; Part 2: Specification for selected limits of size.Information about this documentThis part of BS 3643 has been revised to b
20、ring it up to date.Hazard warningsPresentational conventionsThe provisions of this standard are presented in roman (i.e. upright) type. Its requirements are expressed in sentences in which the principal auxiliary verb is “shall”.Commentary, explanation and general informative material is presented i
21、n smaller italic type, and does not constitute a normative element.Contractual and legal considerationsThis publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot conferimmunity f
22、rom legal obligations.WARNING. Attention is drawn to the fact that, with the differentscrew thread forms available, there is the possibility of a mismatch,which is potentially hazardous. It is the responsibility of the designer of the end product toensure thatthis possibility is reduced to a minimum
23、. For further information on mismatches of screw thread systems see PD 6494.BS 3643-2:2007ii The British Standards Institution 2014This part of BS 3643 is published by BSI Standards Limited, under licence from The British Standards Institution, and came into effect on 30 November 2007. It was prepar
24、ed by Subcommittee SFTSE/1, Screws and fasteners technical specification committee, under the authority of Technical Committee FME/9, Nuts, bolts and accessories. A list of organizations represented on this committee can be obtained on request to its secretary.Text introduced by or altered Corrigend
25、um No. 1 is indicated in the text by tags . Minor editorial corrections are not tagged. BSI 2007 1BS 3643-2:20071ScopeThis part of this BS 3643 specifies the fundamental deviations, tolerances and limits of size for the tolerance classes 4H, 5H, 6H and7H for internal threads and 4h, 6g and 8g for ex
26、ternal threads where appropriate for:a coarse pitch series with the range 1 mm to 68 mm diameter;a fine pitch series with the range 1 mm to 33 mm diameter;aconstant pitch series with the range 8 mm to 300 mm diameter.For certain diameter/pitch combinations, the fundamental deviations, tolerances and
27、 limits of size for tolerance class 4H for internal threads and tolerance classes 6h and 4g for external threads, primarily for aerospace use, are specified in Annex A. 2Normative referencesThe following referenced documents are indispensable for the application of this document. For dated reference
28、s, only the edition cited applies.For undated references, the latest edition of the referenced document (including any amendments) applies.BS 3643-1:2007, ISO metric screw threads Principles and basic data3Terms and definitionsFor the purposes of this part of BS 3643 the terms and definitions given
29、in BS 3643-1:2007 apply.BS 3643-2:2007 The British Standards Institution 2014 1BS 3643-2:20072 BSI 20074DesignationThe complete designation for a screw thread shall comprise a designation for the threadsystem and a designation for the threadtolerance class in accordance with BS 3643-1:2007, 7.3.EXAM
30、PLES:External threadInternal thread5RequirementsFundamental deviations, tolerances and limits of size shall be as specified in Table 1.NOTE For the minor diameter of external threads Table 1 specifies the minimum dimensions only. The maximum dimensions have not beenspecified because of the requireme
31、nt in BS 3643-1:2007, 7.9, that these dimensions are to be controlled by the GO gauge.BS 3643-2:20072 The British Standards Institution 2014 BSI 2007 3BS 3643-2:2007Table 1ISO metric screw threads Limits and tolerances for finisheduncoatedthreadsfor normal lengthofengagementAll dimensions arein mill
32、imetres.12345678910111213141516171819202122NominaldiameterPitchExternalthreads Internal threadsCoarseFineConstantTolerance classFunddev.Major diameterPitch diameterMinordiameterToleranceclassFund dev.Major diameterPitchdiameterMinordiametermax.tol.min.max.tol.min.min.min.max.tol.min.max.tol.min.10.2
33、4h01.0000.0360.9640.8700.0300.8400.7174H01.0000.9100.0400.8700.8210.0380.7836g0.0170.9830.0560.9270.8530.0480.8050.6820.254h01.0000.0420.9580.8380.0340.8040.6494H0 1.0000.8830.0450.8380.7740.0450.7296g0.0180.9820.0670.9150.8200.0530.7670.6135H01.0000.8940.0560.8380.7850.0560.7291.10.24h01.1000.0361.
34、0640.9700.0300.9400.8174H01.1001.0100.0400.9700.9210.0380.8836g0.0171.0830.0561.0270.9530.0480.9050.7820.254h01.1000.0421.0580.9380.0340.9040.7504H0 1.1000.9830.0450.9380.8740.0450.8296g0.0181.0820.0671.0150.9200.0530.8670.7135H01.1000.9940.0560.9380.8850.0560.8291.20.24h01.2000.0361.1641.0700.0301.
35、040 0.9174H01.2001.1100.0401.070 1.021 0.038 0.9836g0.0171.1830.0561.1271.0530.0481.0050.8820.254h01.2000.0421.1581.038 0.034 1.004 0.8504H01.2001.083 0.0451.038 0.974 0.045 0.9296g0.0181.1820.0671.1151.0200.0530.9670.8135H01.2001.0940.0561.0380.9850.0560.9291.40.24h01.4000.036 1.364 1.270 0.030 1.2
36、40 1.1174H01.4001.310 0.0401.270 1.221 0.038 1.1836g0.0171.3830.0561.3271.2530.0481.2051.0820.34h 01.4000.048 1.352 1.205 0.036 1.169 0.9844H01.4001.253 0.0481.205 1.128 0.053 1.0756g0.0181.3820.0751.3071.1870.0561.1310.9465H01.4001.265 0.0601.205 1.142 0.067 1.0756H01.4001.2800.0751.2051.1600.0851.
37、0751.60.24h01.6000.036 1.564 1.470 0.032 1.438 1.3154H01.6001.5120.0421.470 1.421 0.038 1.3836g0.0171.5830.0561.5271.4530.0501.4031.2800.354h01.6000.053 1.547 1.373 0.040 1.333 1.1174H01.6001.4260.0531.373 1.284 0.063 1.2216g0.0191.5810.0851.4961.3540.0631.2911.0755H01.6001.440 0.0671.373 1.301 0.08
38、0 1.2216H01.6001.4580.0851.3731.3210.1001.221BS 3643-2:2007 The British Standards Institution 2014 34 BSI 2007BS 3643-2:2007Table 1ISO metric screw threads Limits and tolerances for finisheduncoatedthreads for normal lengthofengagement (continued)All dimensions arein millimetres.12345678910111213141
39、516171819202122NominaldiameterPitchExternal threadsInternalthreadsCoarseFineConstantTolerance classFund dev.MajordiameterPitch diameterMinordiameterToleranceclassFund dev.Major diameterPitchdiameterMinordiametermax.tol.min.max.tol.min.min.min.max.tol.min.max.tol.min.1.80.24h01.8000.0361.764 1.670 0.
40、032 1.638 1.5154H01.8001.712 0.042 1.670 1.621 0.0381.5836g0.0171.7830.0561.7271.6530.0501.6031.4800.354h01.8000.0531.7471.5730.0401.5331.3174H01.8001.626 0.053 1.5731.4840.0631.4216g0.0191.7810.0851.6961.5540.0631.4911.2755H01.8001.640 0.067 1.5731.5010.0801.4216H01.8001.6580.0851.5731.5210.1001.42
41、120.254h02.0000.0421.9581.8380.0361.8021.6484H0 2.0001.8860.0481.8381.7740.0451.7296g0.0181.9820.0671.9151.8200.0561.7641.6105H02.0001.8980.0601.8381.7850.0561.7290.44h02.0000.0601.9401.7400.0421.6981.4524H0 2.0001.7960.0561.7401.6380.0711.5676g0.0191.9810.0951.8861.7210.0671.6541.4085H0 2.0001.8110
42、.0711.7401.6570.0901.5676H02.0001.8300.0901.7401.6790.1121.5672.20.254h02.2000.0422.1582.0380.0362.0021.8484H02.2002.0860.0482.0381.9740.0451.9296g0.0182.1820.0672.1152.0200.0561.9641.8105H02.2002.0980.0602.0381.9850.0561.9290.454h02.2000.0632.1371.9080.0451.8631.5854H02.2001.9680.0601.9081.7930.080
43、1.7136g0.0202.1800.1002.0801.8880.0711.8171.5395H02.2001.9830.0751.9081.8130.1001.7136H02.2002.0030.0951.9081.8380.1251.7132.50.354h02.5000.0532.4472.2730.0402.2332.0174H02.5002.3260.0532.2732.1840.0632.1216g0.0192.4810.0852.3962.2540.0632.1911.9755H0 2.5002.3400.0672.2732.2010.0802.1216H02.5002.358
44、0.0852.2732.2210.1002.1210.454h02.5000.0632.4372.2080.0452.1631.8854H0 2.5002.2680.0602.2082.0930.0802.0136g0.0202.4800.1002.3802.1880.0712.1171.8395H0 2.5002.2830.0752.2082.1130.1002.0136H02.5002.3030.0952.2082.1380.1252.01330.354h03.0000.0532.9472.7730.0422.7312.5154H0 3.0002.8290.0562.7732.6840.0
45、632.6216g0.0192.9810.0852.8962.7540.0672.6872.4715H0 3.0002.8440.0712.7732.7010.0802.6216H03.0002.8630.0902.7732.7210.1002.6210.54h03.0000.0672.9332.6750.0482.6272.3195H0 3.0002.7550.0802.6752.5710.1122.4596g0.0202.9800.1062.8742.6550.0752.5802.2726H0 3.0002.7750.1002.6752.5990.1402.4597H03.0002.800
46、0.1252.6752.6390.1802.459BS 3643-2:20074 The British Standards Institution 2014 BSI 2007 5BS 3643-2:2007Table 1ISO metric screw threads Limits and tolerances for finisheduncoatedthreadsfor normal lengthofengagement(continued)All dimensions arein millimetres.12345678910111213141516171819202122Nominal
47、diameterPitchExternal threads InternalthreadsCoarseFineConstantToleranceclassFunddev.Major diameterPitchdiameterMinordiameterToleranceclassFund dev.MajordiameterPitchdiameterMinordiametermax.tol.min.max.tol.min.min.min.max.tol.min.max.tol.min.3.50.354h03.5000.0533.4473.2730.0423.2313.0154H03.5003.32
48、90.0563.2733.1840.0633.1216g0.0193.4810.0853.3963.2540.0673.1872.9715H03.5003.3440.0713.2733.2010.0803.1216H03.5003.3630.0903.2733.2210.1003.1210.64h03.5000.0803.4203.1100.0533.0572.6885H03.5003.2000.0903.1102.9750.1252.8506g0.0213.4790.1253.3543.0890.0853.0042.6356H03.5003.2220.1123.1103.0100.1602.
49、8507H03.5003.2500.1403.1103.0500.2002.85040.54h04.0000.0673.9333.6750.0483.6273.3195H04.0003.7550.0803.6753.5710.1123.4596g0.0203.9800.1063.8743.6550.0753.5803.2726H04.0003.7750.1003.6753.5990.1403.4597H04.0003.8000.1253.6753.6390.1803.4590.74h04.0000.0903.9103.5450.0563.4893.0585H04.0003.6400.0953.5453.3820.1403.2426g0.0223.9780.1403.8383.5230.0903.4333.0026H04.0003.6630.1183.5453.4220.1803.2427H04.0003.6950.1503.5453.4660.2243.2424.50.54h04.5000.0674.4334.1750.0484.1273.8195H04.5004.2550.0804.1754.0710.1123.9596g
