1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN ISO 14087:2011Leather Physical andmechanical tests Determination of bendingforce (ISO 14087:2011)Copyright European Committee for Standardization Provided by IHS under lice
2、nse with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN ISO 14087:2011 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN ISO 14087:2011.The UK participation in its preparation was entrusted to TechnicalCommittee TCI/69,
3、 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. Users are responsible for its correctapplication. The British Standards Insti
4、tution 2012ISBN 978 0 580 68693 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 Committee on 31 January 2012.Amendments issued since publicationDate T e x t a f f
5、 e c t e dCopyright 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 ISO 14087 December 2011 ICS 59.140.30 English Version Leather - Phy
6、sical and mechanical tests - Determination of bending force (ISO 14087:2011) Cuir - Essais physiques et mcaniques - Dtermination de la force de flexion (ISO 14087:2011) Leder - Physikalische und mechanische Prfungen - Bestimmung der Biegekraft (ISO 14087:2011) This European Standard was approved by
7、CEN on 30 November 2011. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate 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 stand
8、ards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Standard 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 no
9、tified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithua
10、nia, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2011 CE
11、N All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 14087:2011: ECopyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-
12、,-BS EN ISO 14087:2011EN ISO 14087:2011 (E) 3 Foreword This document (EN ISO 14087:2011) has been prepared by Technical Committee CEN/TC 289 “Leather”, the secretariat of which is held by UNI, in collaboration with IULTCS “International Union of Leather Technologists and Chemists Societies“. This Eu
13、ropean Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, 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 element
14、s of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this Europ
15、ean Standard: 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, Switzerland and th
16、e United Kingdom. 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 14087:2011ISO 14087:2011(E) IULTCS/IUP 54:2011(E) ISO 2011 All rights reserved iiiForeword ISO (the In
17、ternational 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 interested in a subject for which a technical committee h
18、as 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 Electrotechnical Commission (IEC) on all matters of electrotechnical
19、 standardization. International Standards are drafted in accordance with the rules given 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 bodi
20、es 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 document may be the subject of patent rights. ISO shall not be held responsible for identifying any
21、or all such patent rights. ISO 14087 was prepared by the Physical Tests Commission of the International Union of Leather Technologists and Chemists Societies (IUP Commission, IULTCS) in collaboration with the European Committee for Standardisation (CEN) Technical Committee CEN/TC 289, Leather, the s
22、ecretariat of which is held by UNI, in accordance with the agreement on technical co-operation between ISO and CEN (Vienna Agreement). IULTCS, originally formed in 1897, is a world-wide organization of professional leather societies to further the advancement of leather science and technology. IULTC
23、S has three Commissions, which are responsible for establishing international methods for the sampling and testing of leather. ISO recognizes IULTCS as an international standardizing body for the preparation of test methods for leather. Copyright European Committee for Standardization Provided by IH
24、S under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN ISO 14087:2011Copyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS
25、EN ISO 14087:2011INTERNATIONAL STANDARD ISO 14087:2011(E)IULTCS/IUP 54:2011(E) ISO 2011 All rights reserved 1Leather Physical and mechanical tests Determination of bending force 1 Scope This International Standard describes a test method for the determination of the bending force of leather. 2 Norma
26、tive references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 2418, Leather Chemical, physi
27、cal and mechanical and fastness tests Sampling location ISO 2419, Leather Physical and mechanical tests Sample preparation and conditioning ISO 2589, Leather Physical and mechanical tests Determination of thickness 3 Terms and definitions For the purposes of this document, the following terms and de
28、finitions apply. 3.1 bending force force exerted by the specimen on the measuring bar at a specified bending angle, bending length and bending rate 3.2 bending angle angle at which the bending force is measured 3.3 bending length length around which the specimen is bent NOTE The bending length is th
29、e distance between the clamping device of the specimen and the bar onto which the force of the specimen is transferred. 3.4 bending rate rate of bending of the specimen NOTE The bending rate is expressed in degrees per sec (/s). 3.5 compression bending compression of the grain side or coating of the
30、 leather during bending 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 14087:2011ISO 14087:2011(E) IULTCS/IUP 54:2011(E) 2 ISO 2011 All rights reserved3.6 extension be
31、nding extension of the grain side or coating of the leather during bending 4 Principle The bending force is determined based on the bar method (two-point bending method). In this method, the specimen is clamped in a rotating fixture. During the rotation, the specimen exerts a force onto a bar. The f
32、orce acting at a specified bending angle is measured. 5 Apparatus 5.1 Device for determining the bending force according to the bar method (two-point bending method) comprising the following. 5.1.1 Clamping mechanism, in which the specimen shall be able to be clamped vertically. The clamping jaws sh
33、all have a depth of (35 1) mm and a minimum width of at least 30 mm (see Figure 1). The clamping device shall enable parallel clamping with an even pressure distribution on the specimen. It shall move smoothly and allow tightening with a torque wrench. The clamping device shall allow for affixing th
34、e specimen without it touching the bar in its initial position. Key 1a fixed clamping jaws 1b moving clamping jaws 2 aperture 6 mm 3 jaw width 30 mm 4 jaw depth (35 1) mm 5 pivot axis Figure 1 Clamping jaws 5.1.2 Means for rotating the clamping device about the pivot axis. The pivot axis is located
35、exactly at the front edge of the fixed clamp (deviation of 0,1 mm) (see Figure 1). Rotation shall be possible within the range of 1 to 91 with a maximum deviation of 0,1. The rotational speed shall be able to be adjusted up to 10 /s with an accuracy of 0,1 /s. At maximum load, the maximum deviation
36、of the rotational speed allowed is 0,1 %. 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 14087:2011ISO 14087:2011(E) IULTCS/IUP 54:2011(E) ISO 2011 All rights reserved
37、 35.1.3 Means of measuring the bending force. The rotation of the specimen causes it to be pressed against a vertical metering bar. (See Figure 2.) The bar is connected to a load cell that allows measurement of forces up to 10 N (optionally, 1 N for very flexible materials) with a minimum resolution
38、 of 0,1 % and a maximum deviation of 0,1 %. The bar design shall exhibit a sharp edge (R 0,05 0,01 mm) and a width of at least 30 mm. The weight of the bar shall not influence the measured value. The distance between the bar and the pivot point shall be adjustable in a range from 0,1 mm to 50 mm wit
39、h an accuracy of 0,1 mm. At the start of the measurement, the specimen is moved towards the bar until contact is made and a defined preliminary force is reached. This preliminary force shall be able to be adjusted with an accuracy of 1 mN. When the preliminary force is reached, the measurement shall
40、 start (angle 0 and force preliminary force setting). The evaluation unit shall ensure measurement of the force at one or more previously defined angles. These angles shall not be identical to the maximum angle of rotation. The measuring apparatus shall ensure that all significant parameters (force,
41、 length, speed) can be checked, calibrated and restored. It is recommended that the measured data (raw data and parameter settings) are able to be electronically archived. Key 1 load cell 2 vertical metering bar 3 bending length adjustable 4 free sample length 5 sample length 6 sample aRotating dire
42、ction. Figure 2 Clamping jaws with specimen, load cell and bar with sharp edge NOTE An example of a commercial source for a suitable device is given in Annex A. 5.2 Torque wrench, suitable for a range from 0,05 Nm to 0,2 Nm with an accuracy of 0,01 Nm. 5.3 Press knife, as specified in ISO 2419 for t
43、he corresponding specimen size. 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 14087:2011ISO 14087:2011(E) IULTCS/IUP 54:2011(E) 4 ISO 2011 All rights reserved6 Sampli
44、ng and sample preparation Sampling is conducted according to ISO 2418 if possible and conditioning according to ISO 2419. The dimensions of the specimens shall be taken from the relevant parameter sets (see 7.1). Other dimensions are permissible but shall be indicated in the test report. The sample
45、is taken parallel with and perpendicular to the backbone. Other sampling angles (e.g. diagonal) are also permissible and details shall be given in the test report. If the orientation of the backbone is not known, each specimen shall be taken in two directions running perpendicular to each other. At
46、least three specimens shall be used in each direction. If both the compression and extension bending tests are to be conducted on the leather sample, an additional three specimens shall be used for each sampling direction. 7 Test procedure 7.1 Each specimen shall be tested only once and shall then b
47、e discarded. The specimen shall be carefully clamped into the test device such that the free-standing part of the specimen corresponds to the clamping length specified in Table 1. A torque wrench (5.2) with a setting of 0,08 Nm shall be used to tighten the clamping jaws. Then, the test shall be star
48、ted with one of the specified parameter sets specified in the table below. The measurement starts at 0 when the specified preliminary force is reached. The measured forces shall be recorded at the required bending angle. Both extension and compression bending of the grain/coated side is possible. For the extension bending test, the leather specimen shall be inserted so that the bar will press on the grain/coated side. For the compression bending test, the leather specimen shall be inserted so that the bar will press on the flesh/back side. Three di
