1、January 2008DEUTSCHE NORM English price group 8No part of this standard 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!$Kl“1409273ww
2、w.din.deDDIN EN ISO 252Conveyor belts Adhesion between constitutive elements Test methods (ISO 252:2007)English version of DIN EN ISO 252:2008-01Frdergurte Lagenhaftung zwischen den Bestandteilen Prfverfahren (ISO 252:2007)Englische Fassung DIN EN ISO 252:2008-01SupersedesDIN EN ISO 252-1:1999-10www
3、.beuth.deDocument comprises 11 pagesDIN EN ISO 252:2008-01 2 National foreword This document was prepared by Technical Committee ISO/TC 41 “Pulleys and belts (including veebelts)”, Subcommittee SC 3 “Conveyor belts” (Secretariat: BSI, United Kingdom) and has been adopted as EN ISO 252:2007 by Techni
4、cal Committee CEN/TC 188 “Conveyor belts” (Secretariat: BSI, United Kingdom). The responsible German body involved in its preparation was the Normenausschuss Kautschuktechnik (Rubber Technology Standards Committee), Technical Committee NA 045-02-05 AA Frdergurte. The DIN Standard corresponding to th
5、e International Standard referred to in clause 2 of the EN is as follows: ISO 36 DIN 53530 Amendments This standard differs from DIN EN ISO 252-1:1999-10 as follows: a) The scope is no longer confined to textile conveyor belts. b) An information has been added that this standard is not applicable to
6、 light conveyor belts as described in ISO 21183-1. Previous editions DIN EN ISO 252-1: 1999-10 National Annex NA (informative) Bibliography DIN 53350, Testing of organic materials Separation test on fabric plies bonded together DIN ISO 6133, Rubber and plastics Analysis of multi-peak traces obtained
7、 in determinations of tear strength and adhesion strength EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN ISO 252June 2007ICS 53.040.20 Supersedes EN ISO 252-1:1999 English VersionConveyor belts - Adhesion between constitutive elements - Testmethods (ISO 252:2007)Courroies transporteuses - Adhrenc
8、e entre lmentsconstitutifs - Mthodes dessai (ISO 252:2007)Frdergurte - Lagenhaftung zwischen den Bestandteilen -Prfverfahren (ISO 252:2007)This European Standard was approved by CEN on 23 May 2007.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the condition
9、s for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN Management Centre or to any CEN member.This European Standard exists in three offic
10、ial versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Be
11、lgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR
12、STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2007 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN ISO 252:2007: EForeword This document (EN ISO 252:
13、2007) has been prepared by Technical Committee ISO/TC 41 “Pulleys and belts (including veebelts)“ in collaboration with Technical Committee CEN/TC 188 “Conveyor belts“, the secretariat of which is held by BSI. This European Standard shall be given the status of a national standard, either by publica
14、tion of an identical text or by endorsement, at the latest by December 2007, and conflicting national standards shall be withdrawn at the latest by December 2007. This document supersedes EN ISO 252-1:1999. According to the CEN/CENELEC Internal Regulations, the national standards organizations of th
15、e following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovaki
16、a, Slovenia, Spain, Sweden, Switzerland and United Kingdom. Endorsement notice The text of ISO 252:2007 has been approved by CEN as EN ISO 252:2007 without any modifications. 2 EN ISO 252:2007 (E) DIN EN ISO 252:2008-01 1 Scope This International Standard specifies two test methods, A and B, for det
17、ermining the adhesion strength between constitutive elements of a conveyor belt, i.e. between plies and between covers and carcass. Basic test conditions are in conformity with ISO 36. It is applicable to all types of construction of conveyor belting with the exception of belts containing steel cord
18、 reinforcement, and textile-reinforced belts with a full-thickness tensile strength of less than 160 N/mm. It is not suitable or valid for light conveyor belts as described in ISO 21183-11. NOTE Methods A and B are alternative options, but the mean adhesive force values calculated for the two method
19、s can be different. Also, as both methods might not be equally suitable for all belt constructions, it is advisable that the advice of the belt manufacturer be sought. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated referenc
20、es, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 36, Rubber, vulcanized or thermoplastic Determination of adhesion to textile fabrics ISO 6133, Rubber and plastics Analysis of multi-peak traces obtained
21、in determinations of tear strength and adhesion strength ISO 18573, Conveyor belts Test atmospheres and conditioning periods 3 Principle The mean force required to strip the covers from the carcass, and also each ply from the next, is determined using a constant rate of traverse machine. 4 Apparatus
22、 Suitable power-driven tensile testing machine, conforming to ISO 36. 5 Test pieces 5.1 Time between manufacture and test The time between completion of production and the commencement of testing shall be not less than 24 h; this period shall include the conditioning periods given in 5.5. 3 EN ISO 2
23、52:2007 (E) DIN EN ISO 252:2008-01 5.2 Shape and dimensions Each test piece shall consist of a strip of belting of rectangular cross-section with clean-cut edges, (25 0,5) mm wide and 200 mm minimum in length, so as to permit a length of at least 100 mm to be stripped. If necessary and where possibl
24、e, the thickness shall be reduced to a value which will ensure that during the test the line of separation remains as near as possible to the plane through the axes of the components of the test piece held between the grips (see Figure 1). The minimum thickness shall be such that the weakest compone
25、nt can transmit the necessary force for separation without breaking. Key 1 plane through axes of components of test piece held between grips 2 line of separation (correct alignment with plane through axes) 3 line of separation (incorrect alignment with plane through axes) 4 test piece with reduced t
26、hickness to improve alignment Figure 1 Position of line of separation of plies 5.3 Number For both methods, A and B, two test pieces in the longitudinal direction shall be used. The test may also be conducted with two transverse test pieces, if agreed between the manufacturer and purchaser. 4 EN ISO
27、 252:2007 (E) DIN EN ISO 252:2008-01 5.4 Selection of test pieces from sample The test pieces shall be taken not less than 100 mm from the edges of the available belt sample and from places as widely spaced as possible. 5.5 Conditioning Condition the test pieces in accordance with ISO 18573, using e
28、ither atmosphere D or atmosphere E, and then carry out the tests immediately after completion of the conditioning period. 6 Procedure 6.1 Method A (see Figure 2) At one end of the longitudinal test piece, separate the top cover from the first ply for a distance appropriate to the test grips to be us
29、ed. Fix the separated ends in the grips of the tensile testing machine and make an autographic record of the force required to strip a further 100 mm with a rate of traverse of the driven jaw of (100 10) mm/min. The test piece shall be unsupported. Repeat this procedure using the same test piece for
30、 each consecutive ply up to the middle of the test piece. Carry out a similar series of tests on a second longitudinal test piece but commencing with the bottom cover. If the test is to be carried out on transverse test pieces, conduct the test in the same manner. Any separation occurring outside th
31、e plane of contact between the two components, for example, inside one of the components (such as a cover) subjected to the test, is considered as a rupture of the material which constitutes the component. Such a separation should be noted, but should not be considered as representative of the adhes
32、ion strength. 5 EN ISO 252:2007 (E) DIN EN ISO 252:2008-01 Key 1 top cover 2 bottom cover Figure 2 Sequence of separation of components for method A (5-ply belt shown as example) 6 EN ISO 252:2007 (E) DIN EN ISO 252:2008-01 6.2 Method B (see Figure 3) At one end of the longitudinal test piece, separ
33、ate the top cover from the first ply for a suitable distance appropriate to the test grips to be used. Fix the separated ends in the grips of the tensile testing machine and make an autographic record of the force required to strip a further 100 mm with a rate of traverse of the driven jaw of (100 1
34、0) mm/min. The test piece shall be unsupported. Key 1 top cover 2 bottom cover Figure 3 Sequence of separation of components for method B (5-ply belt shown as example) 7 EN ISO 252:2007 (E) DIN EN ISO 252:2008-01 Repeat this procedure using the same test piece, stripping consecutively two unseparate
35、d plies from the remainder of the test piece. Carry out a similar series of tests on a second longitudinal test piece but commencing by separating the unseparated top cover and first ply from the second ply. If the test is to be carried out on transverse test pieces, conduct the test in the same man
36、ner. Any separation occurring outside the plane of contact between the two components, for example, inside one of the components (such as a cover) subjected to the test, is considered as a rupture of the material which constitutes the component. Such a separation should be noted, but should not be c
37、onsidered as representative of the adhesion strength. 7 Expression of results 7.1 Examination of traces for longitudinal test pieces Examination and analysis of the multi-peak adhesion strength test traces shall be in accordance with ISO 6133. The median peak force is defined as the mean adhesion fo
38、rce. The lowest graphically recorded peak is defined as the minimum adhesion force. Calculate the mean adhesion as the quotient of the mean adhesion force, in Newtons, divided by the nominal width, in millimetres, of the test piece to the nearest 0,1 N/mm. Calculate the minimum adhesion as the quoti
39、ent of the minimum adhesion force, in Newtons, divided by the nominal width, in millimetres, of the test piece to the nearest 0,1 N/mm. 7.2 Examination of traces for transverse test pieces Make calculations in accordance with 7.1 for the two test pieces cut transversely, if applicable. 8 Test report
40、 The test report shall contain the following information: a) reference to this International Standard (i.e. ISO 252); b) identification of the conveyor belt tested; c) time interval between belt manufacture and test piece preparation; d) temperature and times for conditioning and testing; e) test me
41、thod used (A or B); f) mean adhesion, as calculated in accordance with 7.1, for the top cover to ply or carcass measurement, the bottom cover to ply or carcass measurement and for each ply to ply measurement; g) minimum adhesion, as calculated in accordance with 7.1, for the top cover to ply or carc
42、ass measurement, the bottom cover to ply or carcass measurement and for each ply to ply measurement; h) any case where one of the components fails before the adhesion strength between the two components is reached, and the force at which the failure occurred (see final paragraph of 6.1 and 6.2); i) date of the test. 8 EN ISO 252:2007 (E) DIN EN ISO 252:2008-01 Bibliography 1 ISO 21183-1, Light conveyor belts Part 1: Principal characteristics and applications 9 EN ISO 252:2007 (E) DIN EN ISO 252:2008-01
