1、BRITISH STANDARD BS 6102-8: 1990 ISO 6698:1989 Cycles Part 8: Specification for screw threads used to assemble freewheels on bicycle hubsBS6102-8:1990 This British Standard, having been prepared under the directionof the General Mechanical Engineering Standards Policy Committee, waspublished under t
2、he authorityof the Board of BSI andcomes into effect on 30November 1990 BSI 07-1999 The following BSI references relate to the work on this standard: Committee reference GME/25 Draft announced in BSI News October 1990 ISBN 0 580 19110 9 Committees responsible for this British Standard The preparatio
3、n of this British Standard was entrusted by the General Mechanical Engineering Standards Policy Committee (GME/-) to Technical Committee GME/25, upon which the following bodies were represented: Association for Consumer Research Association of Cycle Traders Bicycle Association of Great Britain Briti
4、sh Battery Manufacturers Association British Cycling Federation British Rubber Manufacturers Association Consumer Policy Committee of BSI Cyclists Touring Club Department of Trade and Industry Department of Transport Institute of Trading Standards Administration British Society for the Prevention of
5、 Accidents Small Electrical Appliances Marketing Association Individual manufacturers of cycles Amendments issued since publication Amd. No. Date CommentsBS6102-8:1990 BSI 07-1999 i Contents Page Committees responsible Inside front cover National foreword ii Introduction 1 1 Scope 1 2 Normative refe
6、rences 1 3 Basic ISO thread profile and basic sizes 1 4 Limits and tolerances 2 5 Designation 2 6 Gauging system 2 Figure 1 Basic profiles of British Standard Cycle and ISO threads 5 Figure 2 Thread profiles and tolerance zones for ISO freewheel and hub threads 6 Table 1 Basic dimensions 2 Table 2 L
7、imits and tolerances for screw threads on hubs 2 Table 3 Limits and tolerances for screw threads on freeewheels 3 Table 4 Hub Limits of size for GO screw ring and calliper gauges, and associated screw check, wear and setting plugs 3 Table 5 Hub Limits of size for NOT GO screw ring and calliper gauge
8、s, and associated screw check, wear and setting plugs 4 Table 6 Freewheel Limits of size for GO and NOT GO screw plug gauges 4 Table 7 Hub and freewheel Limits of size for GO and NOT GO plain ring or calliper gauges for hub major diameter, and GO and NOT GO plain plug gauges for freewheel minor diam
9、eter 4 Publication(s) referred to Inside back coverBS6102-8:1990 ii BSI 07-1999 National foreword This part of BS6102 has been prepared under the direction of the General Mechanical Engineering Standards Policy Committee and forms Part of a series implementing corresponding international standards i
10、n the development of which the United Kingdom has played an active part. This Part of BS6102 supersedes BS6102-8:1982 which is withdrawn. This standard is identical with ISO 6698:1989. “Cycles Screw threads used to assemble freewheels on bicycle hubs”, which was prepared by Technical Committee ISO/T
11、C149 of the International Organization for Standardization (ISO). A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity
12、 from legal obligations. Cross-references International standard Corresponding British Standard BS 3643 ISO metric screw threads ISO 68:1973 Part 1:1981 Principles and basic data ISO 965-1:1980 (Technically equivalent) ISO 1502:1978 BS919 Specification for screw gauge limits and tolerances Part 3:19
13、68 Gauges for ISO metric screw threads (Technically equivalent) Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, pages1 to 6, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorpora
14、ted. This will be indicated in the amendment table on the inside front cover.ISO 6698:1989 (E) BSI 07-1999 1 Introduction Inch screw threads of British Standard Cycle (B.S.C.) thread profile are used extensively throughout the world for various applications on bicycle components, and have been stand
15、ardized in national standards. The purpose of this document is to provide an International Standard for the particular screw thread used to assemble freewheels on bicycle hubs: it is based on the use of the ISO basic thread profile and complies as far as is practicable with existing International St
16、andards for general purpose screw threads. The change to an ISO system of screw threads will inevitably take a long time to complete in view of the millions of bicycles now in use which employ B.S.C. thread profile inch screw threads and for which replacement spare parts will be required. For this r
17、eason, in order to minimize changes in production methods during the change to the International Standard, and also to secure satisfactory interchangeability with the B.S.C. screw threads now used, the ISO screw thread in this International Standard has the same pitch as that of the 1,37 in 24 t.p.i
18、. B.S.C. screw thread it is intended to replace; this means that the pitch is in inch units (turns per inch or t.p.i.) but all other dimensions are specified in metric units. A 1 3/8 (1,375) in 24 t.p.i screw thread of ISO basic profile has been adopted in this International Standard. The basic pitc
19、h diameter of this thread differs by only 0,003 mm from that of the 1,37 in 24 t.p.i. B.S.C. thread, but, due to the smaller crest truncation of the ISO profile (seeFigure 1) interference may occur at the major diameter when an ISO hub thread made towards its upper limit is assembled with a B.S.C. f
20、reewheel thread made towards its lower limit on major diameter. The possibility of interference occurring in this manner is considered to be unlikely in practice because of the effect of the manufacturing tolerances (negative on the hub and positive on the freewheel) and the usual practice of using
21、high-crested screwing taps. However, a practical investigation has been carried out and has confirmed that there is little possibility of any interference arising in practice. 1 Scope This International Standard specifies the thread profile and limits and tolerances for the screw threads used to ass
22、emble freewheels on bicycle hubs. It is based on a) the use of the ISO basic thread profile given inISO68; b) satisfactory interchangeability with the corresponding British Standard Cycle (B.S.C.) thread; this has required the use of an inch pitch (t.p.i.); c) the use of screw thread tolerance grade
23、s and tolerance positions given in ISO965-1; d) the use of gauges made to ISO1502. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the editions indicated were va
24、lid. All standards are subject to revision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currently valid International S
25、tandards. ISO 68:1973, ISO general purpose screw threads Basic profile. ISO 965-1:1980, ISO general purpose metric screw threads Tolerances Part 1: Principles and basic data. ISO 1502:1978, ISO general purpose metric screw threads Gauging. 3 Basic ISO thread profile and basic sizes 3.1 Basic profile
26、 The basic profile is that given in ISO68 and is shown in Figure 1. It is the theoretical profile associated with the basic sizes of the major, pitch and minor diameters of the screw thread. 3.2 Basic sizes The basic major diameter, and the basic pitch and minor diameters determined from the basic p
27、rofile, are given in Table 1. ISO 6698:1989 (E) 2 BSI 07-1999 Table 1 Basic dimensions 4 Limits and tolerances 4.1 Fundamental deviations and maximum material limits The fundamental deviations are applied to the basic diameters and establish the maximum material limits. For the hub thread the fundam
28、ental (upper) deviations are negative and correspond to tolerance position “g” on the major, pitch and minor diameters. For the freewheel thread the fundamental (lower) deviations are zero and correspond to tolerance position “H” on the major, pitch and minor diameters. 4.2 Tolerance grades, toleran
29、ces and limits of size The application of tolerances to the maximum material limits, negative tolerances for the hub thread, and positive tolerances for the freewheel thread, determines the minimum material limits of size. The tolerances and limits of size are given in Table 2 and Table 3 respective
30、ly for the hub and the freewheel. The tolerances are grade 6 in accordance with ISO965-1. The fundamental deviations and tolerance zones are shown in Figure 2. 5 Designation Screw threads made to this International Standard are designated by a) the nominal diameter of the thread in inch units, b) th
31、e pitch of the thread in t.p.i., c) the tolerance classes of the freewheel and hub thread respectively. EXAMPLE 1,375 24 6H/6g 6 Gauging system The gauging system is that laid down in ISO1502 to which reference should be made for details of the thread profiles of the screw gauges and the method of g
32、auge application. ISO1502 gives formulae for the calculation of the gauge limits. These formulae have been used to calculate the gauge limits for the freewheel and hub in this International Standard, and these limits are given in Table 4 to Table 7. It should be noted that the pitch diameter limits
33、given in Table 4 to Table 6 relate to the simple pitch diameter, and separate tolerances are given in ISO1502 for the pitch and flank angles of these gauges. These tolerances are Pitch tolerance = 0,005 mm Flank angle tolerance = 0 15 for profiles with complete flanks; = 0 16 for profiles with trunc
34、ated flanks. Table 2 Limits and tolerances for screw threads on hubs Nominal diameter of thread in t.p.i. Basic sizes, mm Major diameter Pitch diameter Minor diameter 1,375 24 34,925 34,238 33,779 t.p.i. Major diameter d mm Pitch diameter d 2 mm Minor diameter d 1 mm max. tol. min. max. tol. min. ma
35、x. 24 34,899 0,180 34,719 34,212 0,125 34,087 33,639 1 2 3 4 5 6 7 8 NOTE 1The tolerances given in columns 3 and 6 are those recommended in ISO965-1 for the nearest metric pitch corresponding to the t.p.i. given in column 1. NOTE 2The grade 6 pitch diameter tolerance differs from the grade 6 major d
36、iameter tolerance. NOTE 3The limit for the maximum minor diameter corresponds to a maximum truncation of 3H/16: this conforms to the specifications for the root contour of external threads given in ISO965-1.ISO 6698:1989 (E) BSI 07-1999 3 Table 3 Limits and tolerances for screw threads on freewheels
37、 Table 4 Hub Limits of size for GO screw ring and calliper gauges, and associated screwcheck, wear and setting plugs t.p.i. Major diameter, D mm Pitch diameter, D 2 mm Minor diameter, D 1 mm D 3min. D min. max. tol. min. max. tol. min. 24 35,001 34,925 34,408 0,170 34,238 34,015 0,236 33,779 1 2 3 4
38、 5 6 7 8 9 NOTE 1The tolerances given in columns 5 and 8 are those recommended in ISO965-1 for the nearest metric pitch corresponding to the t.p.i. given in column 1. NOTE 2The grade 6 pitch diameter tolerance differs from the grade 6 minor diameter tolerance. NOTE 3D 3min. is the diameter to the ra
39、diused root of the freewheel thread that just clears the crest of a maximum hub thread, assuming no clearance between the flanks of the assembled threads. Dimensions in millimetres Type of gauge Major diameter Pitch diameter Minor diameter max. min. max. min. max. min. Solid GO screw ring gauge 34,9
40、84 34,217 34,203 33,760 33,746 Adjustable GO screw ring gauge 34,984 Set on setting plug 33,760 33,746 GO screw calliper gauge Cleared Distance from pitch line to crest is 0,229 5 GO screw check plug for new solid GO screw ring gauge 34,908 34,890 34,199 34,191 33,583 NOT GO screw check plug for new
41、 solid GO screw ring gauge 34,433 5 34,424 5 34,221 34,213 33,593 Wear check plug for solid or adjustable GO screw ring gauge 34,442 5 34,433 5 34,230 34,222 33,593 Setting plug for GO screw calliper gauge 34,908 34,890 34,199 34,191 33,583 Full profile setting plug for adjustable GO screw ring gaug
42、e 34,908 34,890 34,210 34,202 33,593 Truncated profile setting plug for adjustable GO screw ring gauge 34,422 5 34,413 5 34,210 34,202 33,593 ISO 6698:1989 (E) 4 BSI 07-1999 Table 5 Hub Limits of size for NOT GO screw ring and calliper gauges, and associatedscrew check, wear and setting plugs Table
43、6 Freewheel Limits of size for GO and NOT GO screw plug gauges Table 7 Hub and freewheel Limits of size for GO and NOT GO plain ring or callipergaugesfor hub major diameter, and GO and NOT GO plain plug gauges forfreewheelminor diameter Dimensions in millimetres Type of gauge Major diameter Pitch di
44、ameter Minor diameter max. min. max. min. max. min. Solid NOT GO screw ring gauge Cleared 34,908 34,087 34,073 33,882 33,854 Adjustable NOT GO screw ring gauge Cleared 34,908 Set on setting plug 33,882 33,854 NOT GO screw calliper gauge Thread profile size as for NOT GO screw ring gauge GO screw che
45、ck plug for new solid NOT GO screw ring gauge 34,908 34,890 34,069 34,061 33,453 NOT GO screw check plug for new solid NOT GO screw ring gauge 34,783 34,765 34,091 34,083 33,475 Wear check plug for solid or adjustable NOT GO screw ring gauge 34,788 34,770 34,096 34,088 33,475 Setting plug for NOT GO
46、 screw calliper gauge 34,783 34,765 34,080 34,072 33,453 Full profile setting plug for adjustable NOT GO screw ring gauge 34,776 34,758 34,080 34,072 33,475 Truncated profile setting plug for adjustable NOT GO screw ring gauge 34,297 34,279 34,080 34,072 33,475 Dimensions in millimetres Type of gaug
47、e Major diameter Pitch diameter Minor diameter New gauge Worn gauge max. min. max. min. min. max. GO screw plug gauge 34,948 34,926 34,255 5 34,244 5 34,232 5 33,626 NOT GO screw plug gauge 34,636 5 34,614 5 34,419 34,408 34,402 33,626 Dimensions in millimetres Type of gauge GO gauge NOT GO gauge Ne
48、w gauge Worn gauge max. min. max. min. Plain ring or calliper gauge 34,869 34,853 34,899 max. 34,727 34,711 Plain plug gauge 33,825 33,809 33,779 min. 34,023 34,007ISO 6698:1989 (E) BSI 07-1999 5 Figure 1 Basic profiles of British Standard Cycle and ISO threadsISO 6698:1989 (E) 6 BSI 07-1999 Figure
49、2 Thread profiles and tolerance zones for ISO freewheel and hub threadsBS6102-8:1990 BSI 07-1999 Publication(s) referred to See national foreword.BS 6102-8: 1990 ISO 6698:1989 BSI 389 Chiswick High Road London W4 4AL BSIBritishStandardsInstitution BSI is the independent national body responsible for preparing BritishStandards. It presents the UK view on standards in Europe and at the international level. It is incorporated by Royal Charter. Revisions BritishStandar
