1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS ISO 2285:2013Rubber, vulcanized orthermoplastic Determinationof tension set under constantelongation, and of tension set,elongation and creep underconstant tensile loadBS ISO
2、2285:2013 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 2285:2013. Itsupersedes BS ISO 2285:2007 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee PRI/22, Physical testing of rubber.A list of organizations represen
3、ted 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 Institution 2013. Published by BSI StandardsLimited 2013ISBN 978 0 580 7485
4、1 6ICS 83.060Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 30 June 2013.Amendments issued since publicationDate Text affectedBS ISO 2285:2013 ISO 2013Rubber, vul
5、canized or thermoplastic Determination of tension set under constant elongation, and of tension set, elongation and creep under constant tensile loadCaoutchouc vulcanis ou thermoplastique Dtermination de la dformation rmanente sous allongement constant et de la dformation rmanente, de lallongement e
6、t du fluage sous charge constante de tractionINTERNATIONAL STANDARDISO2285Seventh edition2013-01-15Reference numberISO 2285:2013(E)BS ISO 2285:2013ISO 2285:2013(E)ii ISO 2013 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2013All rights reserved. Unless otherwise specified, no part of this publ
7、ication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCase postale 56 CH-1211 Geneva
8、 20Tel. + 41 22 749 01 11Fax + 41 22 749 09 47E-mail copyrightiso.orgWeb www.iso.orgPublished in SwitzerlandBS ISO 2285:2013ISO 2285:2013(E) ISO 2013 All rights reserved iiiContents PageForeword iv1 Scope . 12 Normative references 13 Terms and definitions . 24 Apparatus . 24.1 Constant-elongation me
9、asurements 24.2 Constant-load measurements 35 Calibration 46 Test pieces . 46.1 Preparation 46.2 Test pieces for testing under constant elongation . 46.3 Test pieces for testing under constant load . 56.4 Marking . 56.5 Number of test pieces . 56.6 Time interval between forming and testing 56.7 Cond
10、itioning 67 Procedure. 67.1 Testing under constant elongation 67.2 Testing under constant load 88 Expression of results 88.1 General . 88.2 Constant elongation 88.3 Constant load 99 Test report . 9Annex A (normative) Calibration schedule 11Bibliography .13BS ISO 2285:2013ISO 2285:2013(E)ForewordISO
11、(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 interested in a subject for which a technical comm
12、ittee 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 Electrotechnical Commission (IEC) on all matters of electrote
13、chnical 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
14、 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 document may be the subject of patent rights. ISO shall not be held responsible for identifying
15、any or all such patent rights.ISO 2285 was prepared by Technical Committee ISO/TC 45, Rubber and rubber products, Subcommittee SC 2, Testing and analysis.This seventh edition cancels and replaces the sixth edition (ISO 2285:2007), which has been aligned with ISO 815-1 and an annex containing a calib
16、ration schedule has been added.iv ISO 2013 All rights reservedBS ISO 2285:2013INTERNATIONAL STANDARD ISO 2285:2013(E)Rubber, vulcanized or thermoplastic Determination of tension set under constant elongation, and of tension set, elongation and creep under constant tensile loadWARNING Persons using t
17、his International Standard should be familiar with normal laboratory practice. This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health practices and to ensure compliance wit
18、h any national regulatory conditions.CAUTION Certain procedures specified in this International Standard might involve the use or generation of substances, or the generation of waste, that could constitute a local environmental hazard. Reference should be made to appropriate documentation on safe ha
19、ndling and disposal after use.1 ScopeThis International Standard specifies a number of methods of determining the dimensional changes in test pieces of vulcanized or thermoplastic rubber during and after tensile loading for relatively short periods under constant elongation or constant loading.The c
20、onstant-elongation test is intended to measure the ability of rubbers to retain their elastic properties after extension, at a standard laboratory temperature, to a specified strain which is maintained for a specified time at the same or at a specified higher temperature and then released at the tes
21、t temperature or at the standard laboratory temperature.The constant-load test specifies a method for the determination of elongation, creep and tension set of rubbers subjected to a constant load at standard laboratory temperature.The test methods are intended to measure the elastic properties of r
22、ubber in the hardness range 20 IRHD to 94 IRHD.The creep measurement is not recommended for product design or the evaluation of low-creep materials. For these, reference should be made to ISO 8013. No agreement between the results of this test and those of ISO 8013 should be inferred.NOTE The consta
23、nt-load test is primarily intended for the measurement of state of cure and the quality control of thin-walled products. An increase in the state of cure or degree of crosslinking is usually reflected in a decrease in set, creep or elongation.2 Normative referencesThe following referenced documents
24、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 188, Rubber, vulcanized or thermoplastic Accelerated ageing and heat resistance t
25、estsISO 8013, Rubber, vulcanized Determination of creep in compression or shearISO 18899:2004, Rubber Guide to the calibration of test equipmentISO 23529:2010, Rubber General procedures for preparing and conditioning test pieces for physical test methods ISO 2013 All rights reserved 1BS ISO 2285:201
26、3ISO 2285:2013(E)3 Terms and definitionsFor the purposes of this document, the following terms and definitions apply (see also the definitions of creep functions given in ISO 8013).3.1tension set at constant loadelongation remaining in a test piece in the unloaded condition after it has been subject
27、ed to a constant load during a specified time, expressed as a percentage of the original length in the unloaded condition3.2tension set at constant elongationelongation remaining in a test piece in the relaxed condition after it has been subjected to a constant elongation during a specified time, ex
28、pressed as a percentage of the elongation3.3creepincrease in elongation of a test piece at constant load during a specified time, expressed as a percentage of the elongation at the beginning of that time4 Apparatus4.1 Constant-elongation measurements4.1.1 Straining device, consisting of a metal rod
29、or other suitable guide fitted with pairs of holders, one fixed and one moveable, for the ends of the test piece. The holders shall be in the form of self-tightening clamps for strip test pieces, in the form of jaws to hold tab (enlarged) ends, and in the form of flat pulleys of about 5 mm width and
30、 10 mm diameter for ring test pieces.If so desired, a means of operating the moving holder other than by hand may be provided, for example a threaded rod. Suitable stops or graduations may also be provided to avoid over-extension in the initial straining of the test piece.The straining device shall
31、be so designed that, when used at high temperatures in an oven, it can be placed with the reference length of the test piece perpendicular to the direction of the air flow. It shall also be of minimum mass in order to avoid excessive lag in the attainment of temperature equilibrium after its introdu
32、ction into the oven.A multiple-unit straining device may be used, provided that the foregoing requirements are met.4.1.2 Oven, conforming to the requirements of ISO 188 (if the test is to be carried out at a temperature above the standard laboratory temperature). For short heating times, controlled
33、air flow is not necessary.4.1.3 Length-measuring device, capable of measuring the reference length of the test piece to the nearest 0,1 mm.For strip test pieces, a marker shall be provided to mark the length used as the reference length.For ring test pieces, the reference length may be the inner dia
34、meter of the ring, in which case a graduated cone allowing measurements to be made to the nearest 0,1 mm shall be used. Alternatively, if measurements are to be made on a straight reference length, a rigid channel, 3,5 mm deep and 20 mm wide for large ring test pieces and 1,75 mm deep and 10 mm wide
35、 for small ring test pieces, shall be provided for straightening portions of such test pieces during marking and measuring of the reference length.2 ISO 2013 All rights reservedBS ISO 2285:2013ISO 2285:2013(E)4.2 Constant-load measurements4.2.1 Straining device, comprising clamps and weights, or equ
36、ivalent, for loading the test pieces (see Figure 1).Key1 fixed clamp2 test piece3 clamp for holding weight4 weightFigure 1 Straining device4.2.2 Thickness- and width-measuring device, comprising a gauge for measuring the thickness and, where appropriate, the width of the test piece in accordance wit
37、h ISO 23529:2010, method A.The width of die-cut test pieces shall be taken as the distance between the cutting edges of the die in the narrow part, in which case a device capable of measuring the width to the nearest 0,05 mm in accordance with ISO 23529 shall be provided.4.2.3 Length-measuring devic
38、e, capable of measuring the reference length to the nearest 0,1 mm. ISO 2013 All rights reserved 3BS ISO 2285:2013ISO 2285:2013(E)5 CalibrationThe test apparatus shall be calibrated in accordance with the schedule given in Annex A.6 Test pieces6.1 PreparationTest pieces shall be prepared in accordan
39、ce with ISO 23529. They shall be cut from flat sheet 2 mm 0,2 mm thick (except large ring test pieces, which shall be cut from sheet 4 mm 0,2 mm thick) prepared by moulding or slitting and buffing in accordance with ISO 23529.Strip test pieces and strip test pieces with enlarged ends shall be cut us
40、ing a sharp die with a cutter as specified in ISO 23529.Ring test pieces shall be cut from sheet by means of a pair of concentric circular dies or rotating cutters. The separation of the two cutting edges shall not differ from the average value by more than 0,05 mm.6.2 Test pieces for testing under
41、constant elongation6.2.1 Strip test piecesStrip test pieces shall be between 2 mm and 10 mm wide. A width of 6 mm is preferred.The length of any given strip depends on the selected reference length and the type of straining device.6.2.2 Strip test pieces with enlarged endsTest pieces with enlarged e
42、nds shall be as shown in Figure 2, with a narrow section of length between 25 mm and 50 mm which shall be used as the reference length.Dimensions in millimetresThickness 2 mm 0,2 mmFigure 2 Test piece with enlarged ends6.2.3 Ring test piecesRing test pieces shall be of one of the following sizes:Lar
43、ge ring test piece: thickness: 4 mm 0,2 mm; outer diameter: 52,6 mm 0,2 mm; inner diameter: 44,6 mm 0,2 mm.4 ISO 2013 All rights reservedBS ISO 2285:2013ISO 2285:2013(E)Small ring test piece: thickness: 2 mm 0,2 mm; outer diameter: 33,5 mm 0,2 mm; inner diameter: 29,5 mm 0,2 mm.6.3 Test pieces for t
44、esting under constant loadTest pieces shall have the shape and dimensions shown in Figure 3.Dimensions in millimetresThickness 2 mm 0,2 mmFigure 3 Test piece for constant loading6.4 Marking6.4.1 GeneralReference marks shall be marked on the test pieces, using a suitable marker and an ink which does
45、not affect the material and withstands the temperature of test.6.4.2 Tests at constant elongationThe reference length shall be between 25 mm and 50 mm, measured between the inner sides of the marks. For strip test pieces, the preferred length is 50 mm. Ring test pieces shall be straightened by means
46、 of a rigid channel (see 4.1.3) and the reference length, preferably 40 mm for large ring test pieces and 25 mm for small ring test pieces, shall be marked on one of the straightened sides.6.4.3 Tests at constant loadTwo reference marks shall be marked on the central part of the test piece at a dist
47、ance of 90 mm 0,5 mm from each other.6.5 Number of test piecesFor each test, a minimum of three test pieces shall be used. (For material with a calendering grain, three test pieces shall be taken in each of two directions at right angles to each other.)6.6 Time interval between forming and testingTh
48、e time interval between forming and testing shall be in accordance with ISO 23529. ISO 2013 All rights reserved 5BS ISO 2285:2013ISO 2285:2013(E)Samples and test pieces shall be protected from light as completely as possible during the interval between forming and testing.6.7 ConditioningPrepared te
49、st pieces shall be conditioned immediately before testing for a minimum period of 3 h at one of the standard laboratory temperatures defined in ISO 23529, the same temperature being used throughout any one test or series of tests intended to be comparable.7 Procedure7.1 Testing under constant elongation7.1.1 Measurement of the test piecesMeasure the unstrained reference length (L1) of each test piece to the nearest 0,1 mm at standard laboratory temperature. Insert the test pieces in the straining d
