1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN ISO 3376:2011Leather Physical andmechanical tests Determination of tensilestrength and percentageextension (ISO 3376:2011)Copyright European Committee for Standardization P
2、rovided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN ISO 3376:2011 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN ISO 3376:2011.It supersedes BS EN ISO 3376:2002 which is withdrawn.The UK
3、participation in its preparation was entrusted to TechnicalCommittee TCI/69, Footwear, leather and coated fabrics.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. U
4、sers are responsible for its correctapplication. The British Standards Institution 2012ISBN 978 0 580 67827 1ICS 59.140.30Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Commit
5、tee on 31 January 2012.Amendments issued since publicationDate Text affectedCopyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN I
6、SO 3376 December 2011 ICS 59.140.30 Supersedes EN ISO 3376:2002English Version Leather - Physical and mechanical tests - Determination of tensile strength and percentage extension (ISO 3376:2011) Cuir - Essais physiques et mcaniques - Dtermination de la rsistance la traction et du pourcentage dallon
7、gement (ISO 3376:2011) Leder - Physikalische und mechanische Prfungen - Bestimmung der Zugfestigkeit und der prozentualen Dehnung (ISO 3376:2011) This European Standard was approved by CEN on 14 December 2011. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate
8、the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Standa
9、rd exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the natio
10、nal standards bodies of Austria, Belgium, Bulgaria, Croatia, 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, Switzerl
11、and and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2011 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN
12、ISO 3376:2011: ECopyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN ISO 3376:2011EN ISO 3376:2011 (E) 3 Foreword This document (EN ISO 3376:2011) has been prepared by Technical
13、 Committee CEN/TC 289 “Leather”, the secretariat of which is held by UNI, in collaboration with the International Union of Leather Technologists and Chemists Societies. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorseme
14、nt, at the latest by June 2012, and conflicting national standards shall be withdrawn at the latest by June 2012. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any
15、 or all such patent rights. This document supersedes EN ISO 3376:2002. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmar
16、k, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Copyright European Committee for Standardization Provided by IH
17、S under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN ISO 3376:2011ISO 3376:2011(E) IULTCS/IUP 6:2011(E) ISO 2011 All rights reserved iiiForeword ISO (the International Organization for Standardization) is a worldwide federation of national
18、standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International
19、 organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules g
20、iven in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at leas
21、t 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 3376 was prepared by the European Committee for Stand
22、ardization (CEN) Technical Committee CEN/TC 289, Leather, in collaboration with the Physical Test Commission of the International Union of Leather Technologists and Chemists Societies (IUP Commission, IULTCS), in accordance with the Agreement on technical cooperation between ISO and CEN (Vienna Agre
23、ement). IULTCS, originally formed in 1897, is a world-wide organization of professional leather societies to further the advancement of leather science and technology. IULTCS has three Commissions, which are responsible for establishing international methods for the sampling and testing of leather.
24、ISO recognizes IULTCS as an international standardizing body for the preparation of test methods for leather. This third edition cancels and replaces the second edition (ISO 3376:2002), which has been technically revised in 4.4, 6.2.1, 7.1 and 8. Copyright European Committee for Standardization Prov
25、ided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN ISO 3376:2011Copyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IH
26、S-,-,-BS EN ISO 3376:2011INTERNATIONAL STANDARD ISO 3376:2011(E)IULTCS/IUP 6:2011(E) ISO 2011 All rights reserved 1Leather Physical and mechanical tests Determination of tensile strength and percentage extension 1 Scope This International Standard specifies a method for determining the tensile stren
27、gth, elongation at a specified load and elongation at break of leather. It is applicable to all types of leather. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated refere
28、nces, the latest edition of the referenced document (including any amendments) applies. ISO 2418, Leather Chemical, physical and mechanical and fastness tests Sampling location ISO 2419, Leather Physical and mechanical tests Sample preparation and conditioning ISO 2589, Leather Physical and mechanic
29、al tests Determination of thickness ISO 7500-1:2004, Metallic materials Verification of static uniaxial testing machines Part 1: Tension/compression testing machines Verification and calibration of the force-measuring system 3 Principle A test piece is extended at a specified rate until the forces r
30、each a predetermined value or until the test piece breaks. 4 Apparatus 4.1 Tensile testing machine, with: a force range appropriate to the specimen under test; a means of recording the force to an accuracy of at least 2 % as specified by Class 2 of ISO 7500-1; a uniform speed of separation of the ja
31、ws of 100 mm/min 20 mm/min; a means of recording the force, e.g. as an extension curve; jaws, minimum length 45 mm in the direction of the applied load, designed to apply constant clamping by mechanical or pneumatic means. The texture and design of the inside faces of the jaws shall be such that, at
32、 the maximum load attained in the test, the specimen does not slip in either jaw by an amount exceeding 1 % of the original jaw separation. Copyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license fro
33、m IHS-,-,-BS EN ISO 3376:2011ISO 3376:2011(E) IULTCS/IUP 6:2011(E) 2 ISO 2011 All rights reserved4.2 A means of determining the extension of the test piece, either by monitoring the separation of the jaws or by sensors which monitor the separation of two fixed points on the test piece. 4.3 Thickness
34、 gauge, as specified in ISO 2589. 4.4 Press knives, as specified in ISO 2419, capable of cutting a test piece as shown in Figure 1 to the dimensions given in Table 1. Figure 1 Shape of test piece Table 1 Dimensions of test pieces Dimensions in millimetres Designation l l1l2b b1R Standard 110 50 30 1
35、0 20 5 Large 190 100 45 20 40 10 4.5 Vernier callipers, reading to 0,1 mm. 5 Sampling and sample preparation 5.1 Sample in accordance with ISO 2418. 5.2 From the sample, cut six test pieces in accordance with ISO 2419 by applying a press knife (4.4) to the grain surface, three test pieces with the l
36、onger sides parallel to the backbone and three test pieces with the longer sides perpendicular to the backbone. If previous testing has shown that there is slippage of the test piece in the jaws, use the large press knife (4.4). If there is a requirement for more than two hides or skins to be tested
37、 in one batch, then only one test piece in each direction need be taken from each hide or skin, provided that the overall total is not less than three test pieces in each direction. 5.3 Condition the test pieces in accordance with ISO 2419. Copyright European Committee for Standardization Provided b
38、y IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN ISO 3376:2011ISO 3376:2011(E) IULTCS/IUP 6:2011(E) ISO 2011 All rights reserved 36 Procedure 6.1 Determination of dimensions 6.1.1 Using vernier callipers (4.5), measure the width of
39、each test piece to the nearest 0,1 mm at three positions on the grain side and three on the flesh side. In each group of three measurements, make one at the mid-point E (as shown in Figure 1) and the other two at positions approximately midway between the mid-point E and the lines AB and CD. Take th
40、e arithmetic mean of the six measurements as the width of the test piece, w. For soft (“flexible”) leather, the width shall be taken as the width of the press knife. 6.1.2 Measure the thickness of each test piece in accordance with ISO 2589. Make the measurements at three positions, namely the mid-p
41、oint E and at positions approximately midway between the mid-point E and the lines AB and CD. Take the arithmetic mean of the three measurements as the thickness of the test piece, t. 6.2 Determination of tensile strength 6.2.1 Set the jaws of the tensile testing apparatus (4.1) 50 mm 1 mm apart if
42、using the standard test piece or 100 mm apart if using the large test piece. Clamp the test piece in the jaws so that the edges of the jaws lie along the lines AB and CD. When the test piece is clamped, ensure its grain surface lies in one plane. The length axis shall be parallel to the traction dir
43、ection. 6.2.2 Run the machine until the test piece breaks and record the highest force exerted as the breaking force, F. 6.3 Determination of the percentage elongation caused by a specified load 6.3.1 Clamp the test piece between the jaws of the apparatus, as described in 6.2.1. Measure the distance
44、 between the jaws at least to the nearest 0,5 mm and record this distance, L0, as the initial length of the test piece for the purpose of the test. 6.3.2 Start the test. Unless the apparatus automatically draws a force/extension curve with the necessary accuracy (see 4.2), follow the distance betwee
45、n the pair of jaws or the sensors as the force increases. 6.3.3 Note the distance, in millimetres, between the pair of jaws or sensors at the instant when the force first reaches the specified value. This distance represents the length of the test piece at this force, L1. Do not stop the apparatus i
46、f results from the procedures described in 6.2 or 6.4 are also required. 6.4 Determination of the percentage elongation at break 6.4.1 Carry out the steps given in 6.3.1. 6.4.2 Run the tensile test machine until the test piece breaks. 6.4.3 Record the distance between the jaws or sensors at the inst
47、ant when rupture of the test piece occurs. This distance represents the length of the test piece at break, L2. 6.5 Slippage If there is slippage of the test piece in either jaw when tested according to 6.2, 6.3 or 6.4, and the slippage is greater than 1 % of the initial jaw separation, reject the re
48、sult and repeat the determination with a new test piece cut using the large press knife (4.4). Copyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN ISO 3376:2011ISO 3376:2011(E) IULTCS/IUP 6:2011(E) 4 ISO 2011 All rights reserved7 Expression of results 7.1 Tensile strength The tensile strength, Tn, in MPa (or newtons per square millimetre, if required) shall be calculated using the equation: nFTwtwhere F is the highest force reco
