1、BRITISH STANDARD BS ISO 6971:2002 Cranked-link drag chains of welded construction, attachments and sprockets ICS 21.220.30 BS ISO 6971:2002 This British Standard, having been prepared under the direction of the Engineering Sector Policy and Strategy Committee, was published under the authority of th
2、e Standards Policy and Strategy Committee on 11 October 2002 BSI 11 October 2002 ISBN 0 580 40547 8 National foreword This British Standard reproduces verbatim ISO 6971:2002 and implements it as the UK national standard. The UK participation in its preparation was entrusted to Technical Committee MC
3、E/1, Chains and chain wheels for power transmission and conveyors, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international publications referred to in this
4、 document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all the necessary provisions of a cont
5、ract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals f
6、or change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the ISO title page, pages ii to iv, pages 1 to 14, an inside back cover and a back cove
7、r. The BSI copyright date displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date Comments Reference number ISO 6971:2002(E)INTERNATIONAL STANDARD ISO 6971 Second edition 2002-09-15 Cranked-link drag chains of welded construction, att
8、achments and sprockets Chanes racleuses en acier, de construction soude, maillons couds, plaques-attaches et roues dentes BSISO6971:2002BSISO6971:2002iiIS:1796 O2002(E) I SO 2002 All irthgs ersedevr iiiContents Page Foreword iv 1 Scope 1 2 Normative reference 1 3 Chains. 1 3.1 General . 1 3.2 Nomenc
9、lature 1 3.3 Dimensions 1 3.4 Tensile strength. 2 3.5 Length accuracy 2 3.6 Designation 2 3.7 Marking. 2 4 Attachments. 6 4.1 Types 6 4.2 Dimensions 6 5 Sprockets . 9 5.1 Diametral dimensions. 9 5.2 Tooth gap form 12 5.3 Rim profile 13 5.4 Tolerances . 14 5.5 Marking. 14 BSISO6971:2002iiiIS:1796 O20
10、02(E) vi I SO 2002 All irthgs ersedevrForeword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body
11、 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 part in the work. ISO collaborates closely with the International Electrotec
12、hnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by
13、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. Attention is drawn to the possibility that some of the elements of this International Standard may be the subject
14、of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 6971 was prepared by Technical Committee ISO/TC 100, Chains and chain wheels for power transmission and conveyors. This second edition cancels and replaces the first edition (ISO 6971:1982), which
15、has been technically revised. In particular, the references and terminology have been revised to bring them into conformity with other International Standards and current practice. Furthermore, in clause 5, the pitch line clearance of sprockets has been altered for consistency with current industry
16、practice. BSISO6971:2002ivINTENRATIONAL TSANDADR IS:1796 O2002(E)I SO 2002 All irthgs ersedevr 1Cranked-link drag chains of welded construction, attachments and sprockets 1 Scope This International Standard specifies the characteristics of cranked-link 1)drag chains of welded construction suitable f
17、or conveying bulk materials, together with associated attachments and chain sprockets. The chain dimensions specified in this International Standard ensure interchangeability of both complete chains and individual links for repair purposes. This International Standard is applicable to sprockets with
18、 between 5 and 20 teeth. Specifications are also given for five types of attachment for use with the conveyor chains conforming to this International Standard. 2 Normative reference The following normative document contains provisions which, through reference in this text, constitute provisions of t
19、his International StandardInternational Standard. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this International Standard International Standardare encouraged to investigate the possibility of applyi
20、ng the most recent edition of the normative document indicated below. For undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain registers of currently valid International Standards. ISO 286-2, ISO system of limits and fits Part 2: Table
21、s of standard tolerance grades and limit deviations for holes and shafts 3 Chains 3.1 General The chain is designed to operate with the closed end of each link in the forward direction to produce the maximum scraping action against the material to be conveyed. 3.2 Nomenclature The nomenclature of th
22、e chains and their component parts is specified in Figures 1 and 2. 3.3 Dimensions Conveyor chain dimensions shall conform to those given in Table 1 (see Figure 3). Both maximum and minimum dimensions are specified to ensure interchangeability of links made by different chain manufacturers. Although
23、 these represent limits for interchangeability, they shall not necessarily be regarded as limits of tolerance for manufacture. 1) In the USA, the term “offset sidebar” is used in place of “cranked link”. BSISO6971:20021IS:1796 O2002(E) 2 I SO 2002 All irthgs ersedevr3.4 Tensile strength 3.4.1 Minimu
24、m tensile strength The minimum tensile strength is that value which shall be exceeded when a tensile force is applied to a sample which is tested to destruction in accordance with 3.4.2. NOTE This minimum tensile strength is not a working force. It is intended primarily as a comparative figure betwe
25、en chains of different construction. For application information, it is necessary to consult the manufacturers or their published data. 3.4.2 Tensile testing A tensile force, not less than the minimum tensile strength specified in Table 1, shall be applied slowly to the ends of a chain, containing a
26、 minimum of three free pitches, by means of shackles so designed as to allow universal movement. The actual test method is at the discretion of the manufacturer. Failure shall be considered to have occurred at the first point where increasing extension is no longer accompanied by increasing force, i
27、.e. the summit of the force/extension diagram. Any test in which failure occurs adjacent to the shackles shall be disregarded. 3.5 Length accuracy Finished chains shall be measured either in the dry state or after light lubrication. The standard nominal length for measurement shall be that nearest t
28、o 3 048 mm. The chain shall be supported throughout its length and the measuring force specified in Table 1 shall be applied. The finished chain length shall be equal to the nominal chain length 0,32 %0 + . Chains that work in parallel may be matched by agreement between the purchaser and the manufa
29、cturer. 3.6 Designation The designation numbers for welded-steel-type cranked link drag chains are based on the ISO chain numbers given in Table 1. These numbers are derived from those given to the cast type which they replace and have been given the prefix WD to indicate that they are of welded des
30、ign. 3.7 Marking The chains shall be marked with the manufacturers name or trademark and in addition should be marked with the appropriate ISO chain number given in Table 1. The marking of the chain shall not be obscured by the attachments. NOTE The illustration does not define the actual form of th
31、e cranked link. Figure 1 Cranked link chain assembly BSISO6971:20022IS:1796 O2002(E) I SO 2002 All irthgs ersedevr 3Key 1 Cranked plate 2 Barrel 3 Connecting pin NOTE The illustration does not define the actual form of the cranked link. Figure 2 Typical cranked link components BSISO6971:20023IS:1796
32、 O2002(E) 4 I SO 2002 All irthgs ersedevr The overall width of connecting links is b 5+ b 6 ,when riveted b 4+ b 5 ,when there is a fastener at one side 2 b 4 ,when there is a fastener at both sides The line of cranking, or offset, between l 1and l 2is straight. NOTE The illustration does not define
33、 the actual form of the cranked link. a (ref.) b Direction of travel cPitch line Figure 3 Chain dimensions and symbols (see Table 1) BSISO6971:20024IS:1796 O2002(E) I SO 2002 All irthgs ersedevr 5 Table 1 Chain dimensions, measuring forces and tensile strengths Barrel shape Tensile strength Pitch Wi
34、dth accross the barrel with respect to section Z-Z Plate hole for barrel bore Width between plates for sprocket contact at inner end Connecting pin body diameter Chain path depth Barrel diameter or plate depth Crank clearance dimensions Plate end clearance dimensions Width over link at inner end Wid
35、th between plates at outer end Width over pin fastening to centreline Width over pin head to centreline Width over rivet to centreline Chain plate thickness Measuring force Pin heat treated All heat treated p ad 1d 3l 6l 7l 8b 1d 2h 1h 2l 7l 2l 3l 4b 2b 3b 4b 5b 6c ISO chain number nom. max. min. ma
36、x. min. max. max. max. min. min. max. max. max. min. max. max. max. nom. min. min. mm kN WD102 127 38,1 39,1 19,25 14,2 17,5 19,6 162 19,13 39,6 38,12 25,6 25,6 25,4 25,4 197,1 197,6 127,8 117,6 127,8 9,7 2,7 170 245 WD104 152,4 38,1 39,1 19,25 14,2 17,5 19,6 104,6 19,13 39,6 38,12 25,6 25,6 25,4 25
37、,4 136,9 137,4 94 87,4 94 9,7 1,8 170 245 WD110 152,4 38,1 39,1 19,25 14,2 17,5 19,6 228,6 19,13 39,6 38,12 25,6 25,6 25,4 25,4 263,9 264,4 157,5 151,1 157,5 9,7 3,1 170 245 WD112 203,2 38,1 39,1 19,25 14,2 17,5 19,6 228,6 19,13 39,6 38,12 25,6 25,6 25,4 25,4 263,9 264,4 157,5 151,1 157,5 9,7 2,7 17
38、0 245 WD113 152,4 38,1 39,1 22,43 15,7 17,5 19,6 228,6 22,3 39,6 38,12 25,6 25,6 25,4 25,4 270,2 270,7 165,1 157,2 165,1 12,7 3,6 213 253 WD116 203,2 44,45 45,2 19,25 16 20,6 22,6 330,2 19,13 46 45,21 28,7 28,7 28,4 28,4 359,1 359,6 205,2 200,7 205,2 9,7 3,6 245 262 WD118 203,2 50,8 51,8 22,43 20,6
39、23,9 25,9 336,5 22,3 52,3 51,8 35,3 35,3 35 35 378,2 378,7 220 211,1 220 12,7 5,8 311 351 WD122 203,2 50,8 51,8 22,43 20,6 23,9 25,9 222,2 22,3 52,3 51,8 35,3 35,3 35 35 260,6 261,1 162,1 152,4 162,1 12,7 4 311 351 WD480 203,2 50,8 51,8 22,43 20,6 23,9 25,9 282,4 22,3 52,3 51,8 32 35,3 31,7 35 324,1
40、 324,6 193,8 184,2 193,8 12,7 4,4 311 351 a The pitch, p, is a theoretical reference dimension used in the calculation of chain lengths and sprocket dimensions, and is not intended for use in the inspection of individual links. BSISO6971:20025IS:1796 O2002(E) 6 I SO 2002 All irthgs ersedevr4 Attachm
41、ents 4.1 Types This International Standard specifies five types of attachment designated C1, C3, C4, RR and wing with the following characteristics: C1, C3, and C4: have a scraper bar attached to the barrel perpendicular to the direction of travel, as shown in Figure 4; RR: has a triangular spur att
42、ached to each cranked plate, as shown in Figure 5; wing: has an angle section attached to the outer face of each cranked plate, as shown in Figure 6. 4.2 Dimensions The respective dimensions of the attachments shall be as specified in Tables 2 to 6. NOTE The actual form of the attachments is at the
43、discretion of the manufacturer. Figure 4 C1, C3 and C4 attachments (see Tables 2, 3 and 4) BSISO6971:20026IS:1796 O2002(E) I SO 2002 All irthgs ersedevr 7Table 2 Dimensions of C1 attachment Dimensions in millimetres ISO chain number c 2 b 7max.h 3max.WD102 9,7 197,1 62 WD104 9,7 136,9 62 WD110 9,7 2
44、63,9 62 WD112 9,7 263,9 62 WD116 9,7 359,2 68,1 Table 3 Dimensions of C3 attachment Dimensions in millimetres ISO chain number c 2b 7max.h 3max.WD110 12,7 263,9 58,7 WD113 12,7 270,3 58,7 WD118 12,7 378,2 77,7 WD480 12,7 324,1 77,7 Table 4 Dimensions of C4 attachment Dimensions in millimetres ISO ch
45、ain number c 2b 7max.h 3max.WD102 9,7 197,1 96,8 WD104 9,7 136,9 96,8 WD110 9,7 263,9 96,8 WD112 9,7 263,9 96,8 WD113 12,7 270,3 122,2 WD116 9,7 359,2 125,5 WD480 12,7 324,1 128,5 BSISO6971:20027IS:1796 O2002(E) 8 I SO 2002 All irthgs ersedevrFigure 5 RR attachment (see Table 5) Table 5 Dimensions o
46、f RR attachment Dimensions in millimetres ISO chain number h 3max.c 2WD102 65 9,7 WD104 65 9,7 WD110 65 9,7 WD112 65 9,7 WD113 65 12,7 WD116 77,7 9,7 WD118 79,2 12,7 WD480 84,1 12,7 BSISO6971:20028IS:1796 O2002(E) I SO 2002 All irthgs ersedevr 9Figure 6 Wing attachment (see Table 6) Table 6 Dimensio
47、ns of wing attachment Dimensions in millimetres ISO chain number c 2b 7max.h 2max.WD102 9,7 365,3 39,6 WD104 9,7 295,1 39,6 WD110 9,7 434,8 39,6 WD112 9,7 434,8 39,6 WD113 9,7 434,8 39,6 WD116 9,7 561,8 46 WD480 9,7 561,8 52,3 5 Sprockets 5.1 Diametral dimensions 5.1.1 General The sprocket diametral
48、 dimensions are shown in Figure 7 and specified in 5.1.2 to 5.1.6. BSISO6971:20029IS:1796 O2002(E) 01 I SO 2002 All irthgs ersedevrKey b a tooth side relief b f tooth width d pitch circle diameter d a tip diameter d f root diameter d g maximum chain clearance diameter p chordal pitch, equal to chain
49、 pitch r e tooth flank (topping radius) r i barrel seating radius s pitch line clearance z number of teeth pressure angle a Working face b Centreline of tooth Figure 7 Diametral dimensions and tooth form 5.1.2 Pitch circle diameter, d cf dpp = where p cfis the pitch diameter factor according to the number of teeth, as specified in 5.2.4 and Table 7. 5.1.3 Tip diameter, d a() ag f2 dp dh =+ where d gfis the chai
