1、June 2015DEUTSCHE NORM English price group 9No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 53.040.20!%E which comp
2、ly with this standard fulfil the relevant health and safety requirements and thus conform to the acknowledged rules of technology. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. DIN shall not be held responsible for identifying a
3、ny or all such patent rights. Annex A is informative. This document has been prepared in close cooperation with the Timber and Metal Department of the Deutsche Gesetzliche Unfallversicherung (DGUV) (German Social Accident Insurance), Section Hebetechnik und Instandhaltung (Lifting Technology and Mai
4、ntenance). It specifies safety requirements based on the ratios of mean stress at working force to mean stress at manufacturing proof force and to mean stress at breaking force, and also on the manufacturing proof test to be carried out for each chain. DIN 762 Round steel link chains Round steel lin
5、k chains, pitch 5d, for chain conveyors consists of the following parts: Part 1: Grade 3, quenched and tempered Part 2: Grade 5, quenched and tempered Part 3: Grade 7 (at present under preparation) Amendments This standard differs from DIN 762-2:1992-09 as follows: a) the title of the standard has b
6、een changed; ) Translators notes. The German original is incorrect. It should read “1992-09”. DIN 762-2:2015-06 4 b) the standard has been revised in form and substance; c) round steel link chains of grade 3 which have not been case hardened have been replaced by round steel link chains of grade 5;
7、d) in the German original the new term “Nenngre” has been introduced in accordance with DIN 685-100 (= d null t); (in the English translation the term “nominal size” has been changed accordingly in its meaning in the table headings and in the designations); e) in the German original the term “lehren
8、haltig” has been changed to “eng toleriert” in accordance with DIN 685-100 (the English translation of this term, “calibrated”, has been changed accordingly to “close tolerance”); f) in the German original the term “Gewicht” has been changed to “Masse/Meter” in accordance with DIN 685-100 (“mass/met
9、re” in English); g) the values of mass/metre have been updated; h) in the German original the term “Zugkraft” has been changed to “Betriebskraft” (the English translation of this term, “tensile force” has been changed accordingly to “working force”); i) in the German original the term “Dicke” has be
10、en changed to “Durchmesser” (the English translation of this term has been changed accordingly to “diameter” in the table headings); j) nominal size 23 null 115 has been included; k) the tolerances on pitch and gauge length have been changed; l) the values for the manufacturing proof force have been
11、 increased in line with other chain standards; m) an informative Annex A “Bases of calculation” has been included; n) the materials specifications have been brought in line with the revised version of DIN 17115; o) the structure of the standard has been harmonized with European chain standards. Prev
12、ious editions DIN 762: 1943-06, 1955-03, 1971-01 DIN 762-2: 1982-01, 1992-09 DIN 762-2:2015-06 5 1 Scope This document applies to tested, close tolerance round steel link chains of grade 5, with a nominal pitch t = 5 d and with nominal diameters d from 10 mm to 23 mm, for use at service temperatures
13、 of 20 C up to +400 C. It specifies dimensions and mechanical properties (see Annex A). Round steel link chains according to this standard are mainly used as long-link chains in chain conveyors and in bucket elevators, as defined in DIN 15201-1. To avoid confusion with round steel link chains of oth
14、er grades, it shall be ensured before use that the chains bear the required test stamp (see Clause 8) (further information on the use of round steel link chains is given in Clause 10). WARNING Round steel link chains as specified here shall not be used as lifting accessories, slings or loadbearing d
15、evices within the meaning of DIN 15003 in combination with cranes or hoists (further information on the use of round steel link chains is given in Clause 10). 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for it
16、s application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. DIN 685-1, Round steel link chains, tested Part 1: Terms DIN 685-2, Round steel link chains, tested Part 2: Safety requiremen
17、ts DIN 685-3, Round steel link chains, tested Part 3: Test DIN 685-4, Round steel link chains, tested Part 4: Marking, test certificate DIN 685-5, Round steel link chains, tested Part 5: Utilization DIN 685-100, Round steel link chains, tested Part 100: Additional terms DIN 17115, Steels for welded
18、round link chains and chain components Technical delivery conditions VDI 3970, Recommendations for the preparation of a maintenance schedule of conveyors 3 Terms and definitions For the purposes of this document, the terms and definitions given in DIN 685-1 and DIN 685-100 apply. 4 Dimensions and de
19、signation 4.1 Dimensions The bases for calculation of the values for dimensions and masses given in Table 1 are explained in the informative Annex A. DIN 762-2:2015-06 6 Figure 1 Close tolerance round steel link chain Table 1 Dimensions and masses Dimensions in millimetres 1 2 3 4 5 6 7 8 9 10 11 12
20、 Nominal size Diameter Pitch Width Gauge lengthbMass/metre internal external d null t d t b1ab2l Tolerances Tolerances min. max. Tolerances kg/m 10 null 50 10 0,4 50 +0,9 0,5 14,0 36 550 +3 1 1,8 13 null 65 13 0,5 65 +1,2 0,6 18,0 47 715 +4 2 3,1 16 null 80 16 0,6 80 +1,4 0,7 22,5 58 880 +5 2 4,7 18
21、 null 90 18 0,9 90 +1,6 0,8 25,0 65 990 +5 3 5,9 20 null 100 20 1,0 100 +1,8 0,9 28,0 72 1100 +6 3 7,3 23 null 115 23 1,2 115 +2,1 1,0 32,0 83 1265 +7 3 9,7 aThe last chain link of the chain strand shall not be widened through the connecting element in that link. There should be a clearance between
22、the internal width b1and the connecting element equal to at least 10 % of the internal width. bPerfect meshing of chain and chain wheel can be ensured if the chain wheel is made available to the chain manufacturer. 4.2 Designation Designation of a round steel link chain of grade 5, with a nominal si
23、ze of 16 80: Chain DIN 762 5 16 80 Designation to be used when ordering: Example of an order for 100 m of round steel link chain of grade 5, with a nominal size of 16 80: 100 m of chain DIN 762 5 16 80 Example of an order for 200 chain strands of a round steel link chain of grade 5, with a nominal s
24、ize of 16 80, each with n = 7 links: 200 chain strands DIN 762 5 16 80 7 DIN 762-2:2015-06 7 5 Requirements 5.1 Material The steel used shall be fully killed, fine grained, and be stabilized against strain age embrittlement according to DIN 17115, at least steel grade 21Mn5, material number 1.0495.
25、For nominal diameters 20 mm, at least steel grade 24MnSi6, material number 1.0450 according to DIN 17115 is recommended. 5.2 Heat treatment Round steel link chains shall be heat treated and meet the requirements specified in DIN 685-2. 5.3 Dimensions The dimensions of round steel link chains shall b
26、e within the tolerances specified in Table 1. The weld diameter ds shall be no more than 3 % lower than the actual diameter and not exceed the nominal diameter d by more than 8 %. The welds shall be positioned in the middle of the legs of the chain link, the length affected by welding a shall not ex
27、ceed the nominal diameter d. 5.4 Length of chain strand 5.4.1 General Within a delivery, chain strands complying with this standard are subdivided for use in both double-strand and multiple-strand conveyors, into category 1 “with strand length tolerance” and category 2 “with matching tolerance” and
28、determined by the length difference e in accordance with DIN 685-100, 3.13 and 3.14. 5.4.2 Category 1 For long chain strands with strand length tolerance, with a strand length of more than 1 000 mm, the maximum length difference e for strand lengths up to 8 000 mm shall be 32 mm. For larger strand l
29、engths, the actual strand lengths shall be within the strand length tolerance of 0,4 %. NOTE For a strand length of 10 000 m, for example, the maximum length difference e is 40 mm. For strand lengths less than 1 000 mm, the length difference e shall be as specified in DIN 5698-1 for tolerance class
30、A in category 1. 5.4.3 Category 2 For long chain strands with matching tolerances and with a strand length of more than 1 000 mm, which are supplied bundled in pairs, the maximum length difference e for strand lengths up to 8 000 mm shall be 6,4 mm. For larger strand lengths, the actual strand lengt
31、hs shall be within the strand length tolerance of 0,08 % for the bundle. NOTE For a strand length of 10 000 m, for example, the maximum length difference e is 8 mm. During assembly care should be taken to ensure that the bundled strands are installed parallel to one another. In order to avoid interc
32、hanging of the chain strands, bundles should only be opened during the course of assembly. For strand lengths less than 1 000 mm, the length difference e shall be as specified in DIN 5698-1 for tolerance class A in category 2. DIN 762-2:2015-06 8 5.5 Working forces The maximum values for the working
33、 forces generally used in practice are given in Table 2. Table 2 Working forces Nominal size Working forces d t WFv WFh vertical horizontal kN kN 10 null 50 16 20 13 null 65 25 32 16 null 80 40 50 18 null 90 50 63 20 null 100 63 80 23 null 115 80 100 5.6 Mechanical properties The manufacturing proof
34、 force, breaking force and bend deflection of round steel link chains shall be as specified in Table 3, the total ultimate elongation being at least 15 %. Table 3 Mechanical properties 1 2 3 4 Nominal size d null t Manufacturing proof force MPF Breaking force BF Bend deflection f kN kN mm min. min.
35、min. 10 null 50 56 80 13 13 null 65 90 125 17 16 null 80 140 200 21 18 null 90 180 250 23 20 null 100 220 320 26 23 null 115 280 400 30 DIN 762-2:2015-06 9 6 Tests 6.1 Material Proof of compliance of the material used with the specified requirements shall be provided in accordance with DIN 685-3. 6.
36、2 Manufacturing proof test For the manufacturing proof test, the specifications of DIN 685-3 shall apply. 6.3 Final test The final test shall cover a dimensional check, the tensile test and the bend test in accordance with DIN 685-3. For the tensile test, three-link samples shall be used. The values
37、 for the breaking force and the total ultimate elongation shall only apply to round steel link chains with a “natural black” surface condition. Although round steel link chains with a “corrosion protected” surface condition and those with a “bright polished” surface condition have the same material
38、tensile strength, the values for the breaking force and total ultimate elongation are reduced during the tensile test due to the changes in wear behaviour at the crown of the chain links. Thus, the values for the breaking force and the total ultimate elongation shall be deemed to have been reached i
39、f the breaking force is at least 90 % and the total ultimate elongation at least 70 % of the breaking force and total ultimate elongation respectively of a natural black chain of the same nominal size. When checking the length of chain strands, care shall be taken to ensure that each chain strand is
40、 without twist and subjected to a force at least equal to 20 % of the working force. Alternatively, the chain strands may be suspended. Any other tests are to be agreed when ordering. 6.4 Acceptance test For the acceptance test, if agreed, the specifications of DIN 685-3 shall apply. 7 Surface condi
41、tion The standard surface condition shall be natural black. Any other surface conditions are to be agreed when ordering. 8 Marking Marking of chains shall be as specified in DIN 685-4. In addition, the chains shall be marked with the number “5” to denote grade 5. Each chain strand shall be provided
42、with at least one marking. 9 Test certificate The final test of the round steel link chain shall be confirmed by a test certificate as specified in DIN 685-4. DIN 762-2:2015-06 10 10 Use Handling, inspection and maintenance of round steel link chains shall comply with the specifications of DIN 685-5
43、 and VDI 3970. Additionally, it is to be noted that the enlargement of the pitch per chain link due to interlink-wear shall not exceed 4 % of the nominal pitch t, and the enlargement of the gauge length due to interlink-wear shall not exceed 2 % of the nominal gauge length l of the straight chain. 1
44、1 Environmental aspects As a rule, round steel link chains complying with this document are highly durable without loss of quality in the course of their service life. Due to the material used round steel link chains are 100 % recyclable at the end of their life cycle (removal from service), as they
45、 can be melted down completely to produce new materials. The steel obtained from recycling offers the same quality characteristics as steel made from pure iron ore (virgin material). In addition, the quality of recycled steel can be adapted to various new requirements, e.g. by alloying. DIN 762-2:20
46、15-06 11 Annex A (informative) Bases of calculation A.1 General The values given in Table 1 have been calculated on the basis of the principles set out in Table A.1. A detailed explanation is given in A.2. Symbols are represented in Figure A.1. Figure A.1 Dimensions of chain link Table A.1 Calculati
47、on principles Dimensions Calculation principles Nominal diameter d from 10 mm up to 23 mm External width b2 max3,6 null d Internal width b1 min1,4 null d Welded chain leg ds max1,08 null d Unwelded chain leg d 1 null d Width tolerance Bt0,12 null d Clearance smin0,32 null d Length affected by weldin
48、g amax1 null d Nominal pitch t 5 null d Bend deflection f 1,3 null d DIN 762-2:2015-06 12 A.2 Re Table 1 Dimensions and masses A.2.1 Nominal diameter The tolerances for nominal diameters d 16 mm are based on a 4 % tolerance and those for nominal diameters d 18 mm on a 5 % tolerance of nominal diamet
49、er d. The calculated values are rounded to 0,1 mm. These values are given in Table 1, column 3. A.2.2 Pitch The nominal pitch shall be t = 5 d. The calculated values are rounded to 1 mm. The tolerance, in percent, is based on the formula 2,08+ 0,62 Thus, for one pitch (n = 1) there is a resulting tolerance of 2,7 % of the nominal pitch t. This is divided into + 1,8 % (+2/3) and 0,9 % (1/3). The calculated values are rounded to 0,1 mm. A.2.3 Internal width The
