SANS 10815-1-2009 Rubber vulcanized or thermoplastic - Determination of compression set Part 1 At ambient or elevated temperatures《硫化橡胶或热塑性橡胶 压缩永久变形的测定 第1部分 室温或更高温度》.pdf

1、 Collection of SANS standards in electronic format (PDF) 1. Copyright This standard is available to staff members of companies that have subscribed to the complete collection of SANS standards in accordance with a formal copyright agreement. This document may reside on a CENTRAL FILE SERVER or INTRA

2、NET SYSTEM only. Unless specific permission has been granted, this document MAY NOT be sent or given to staff members from other companies or organizations. Doing so would constitute a VIOLATION of SABS copyright rules. 2. Indemnity The South African Bureau of Standards accepts no liability for any

3、damage whatsoever than may result from the use of this material or the information contain therein, irrespective of the cause and quantum thereof. ISBN 978-0-626-22640-4 SANS 10815-1:2009 Edition 1 ISO 815-1:2008 Edition 1SOUTH AFRICAN NATIONAL STANDARD Rubber, vulcanized or thermoplastic Determinat

4、ion of compression set Part 1: At ambient or elevated temperatures This national standard is the identical implementation of ISO 815-1:2008 and is adopted with the permission of the International Organization for Standardization. Published by SABS Standards Division 1 Dr Lategan Road Groenkloof Priv

5、ate Bag X191 Pretoria 0001 Tel: +27 12 428 7911 Fax: +27 12 344 1568 www.sabs.co.za SABS This standard may only be used and printed by approved subscription and freemailing clients of the SABS. SANS 10815-1:2009 Edition 1 ISO 815-1:2008 Edition 1 Table of changes Change No. Date Scope National forew

6、ord This South African standard was approved by National Committee SABS TC 45, Rubber and rubber products, in accordance with the SABS Standards Division, in compliance with annex 3 of the WTO/TBT agreement. This SANS document was published in April 2009. This standard may only be used and printed b

7、y approved subscription and freemailing clients of the SABS.INTERNATIONAL STANDARD ISO 815-1 First edition 2008-02-01 Reference number ISO 815-1:2008(E) ISO 2008 Rubber, vulcanized or thermoplastic Determination of compression set Part 1: At ambient or elevated temperatures Caoutchouc vulcanis ou th

8、ermoplastique Dtermination de la dformation rmanente aprs compression Partie 1: tempratures ambiantes ou levesSANS 10815-1:2009This standard may only be used and printed by approved subscription and freemailing clients of the SABS.ISO 815-1:2008(E) ii ISO 2008 All rights reserved PDF disclaimer This

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12、NT ISO 2008 All rights reserved. Unless otherwise specified, no part of this publication 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 i

13、n the country of the requester. ISO copyright office Case postale 56 CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland SANS 10815-1:2009This standard may only be used and printed by approved subscription and freemailing cl

14、ients of the SABS.ISO 815-1:2008(E) ISO 2008 All rights reserved iii Contents Page 1 Scope 1 2 Normative references 1 3 Principle 2 4 Apparatus . 2 5 Test pieces . 4 6 Test conditions 5 7 Procedure . 5 8 Expression of results 6 9 Precision . 7 10 Test report 7 Annex A (informative) Precision . 8 Ann

15、ex B (informative) Guidance for using precision results . 10 SANS 10815-1:2009This standard may only be used and printed by approved subscription and freemailing clients of the SABS.ISO 815-1:2008(E) iv ISO 2008 All rights reserved Foreword ISO (the International Organization for Standardization) is

16、 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 has been established has the right to be represen

17、ted 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 standardization. International Standards are dr

18、afted 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 bodies for voting. Publication as an International S

19、tandard 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 or all such patent rights. ISO 815-1 was prepare

20、d by Technical Committee ISO/TC 45, Rubber and rubber products, Subcommittee SC 2, Testing and analysis. Together with ISO 815-2, ISO 815-1 cancels and replaces ISO 815:1991, as well as Technical Corrigendum ISO 815:1991/Cor.1:1993, which have been technically revised. The main modifications concern

21、 changes in tolerances and the inclusion of the ageing ovens specified in ISO 188, with a view to improving the precision of the method. ISO815 consists of the following parts, under the general title Rubber, vulcanized or thermoplastic Determination of compression set: Part 1: At ambient or elevate

22、d temperatures Part 2: At low temperatures SANS 10815-1:2009This standard may only be used and printed by approved subscription and freemailing clients of the SABS.INTERNATIONAL STANDARD ISO 815-1:2008(E) ISO 2008 All rights reserved 1 Rubber, vulcanized or thermoplastic Determination of compression

23、 set Part 1: At ambient or elevated temperatures WARNING Persons using this part of ISO 815 should be familiar with normal laboratory practice. This part of ISO 815 does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user to establ

24、ish appropriate safety and health practices and to ensure compliance with any national regulatory conditions. CAUTION Certain procedures specified in this part of ISO 815 may involve the use or generation of substances, or the generation of waste, that could constitute a local environmental hazard.

25、Reference should be made to appropriate documentation on safe handling and disposal after use. 1S c o p e This part of ISO 815 specifies methods for the determination of the compression set characteristics of vulcanized and thermoplastic rubbers at ambient or elevated temperatures. The methods are i

26、ntended to measure the ability of rubbers of hardness within the range 10 IRHD to 95 IRHD to retain their elastic properties at specified temperatures after prolonged compression at constant strain (normally ) under one of the alternative sets of conditions described. For rubber of nominal hardness

27、80 IRHD and above, a lower compression strain is used: for a nominal hardness from 80 IRHD to 89 IRHD and for a nominal hardness from 90 IRHD to 95 IRHD. NOTE 1 When rubber is held under compression, physical or chemical changes can occur that prevent the rubber returning to its original dimensions

28、after release of the deforming force. The result is a set, the magnitude of which depends on the time and temperature of compression as well as on the time and temperature of recovery. At elevated temperatures, chemical changes become increasingly more important and lead to a permanent set. NOTE 2 S

29、hort-time compression set tests, typically for , at elevated temperatures are commonly used as a measure of the state of cure, a means of material classification and a specification to ensure the quality of a compound. Longer tests, typically for , at elevated temperatures take account of the effect

30、 of ageing and are often used to predict service performance, including that of sealing materials. Short-time tests at ambient temperature show mainly the effect of physical changes (re-orientation of the molecular chains and the fillers). 2 Normative references The following referenced documents ar

31、e 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 188:2007, Rubber, vulcanized or thermoplastic Accelerated ageing and heat resistan

32、ce tests ISO 4287, Geometrical Product Specifications (GPS) Surface texture: Profile method Terms, definitions and surface texture parameters ISO/TR 9272, Rubber and rubber products Determination of precision for test method standards 25 % 15 % 10 % 22 h 1 000 h SANS 10815-1:2009This standard may on

33、ly be used and printed by approved subscription and freemailing clients of the SABS.ISO 815-1:2008(E) 2 ISO 2008 All rights reserved ISO 23529:2004, Rubber General procedures for preparing and conditioning test pieces for physical test methods 3P r i n c i p l e A test piece of known thickness is co

34、mpressed at standard laboratory temperature to a defined strain, which is then maintained constant for a specified time at standard laboratory temperature or a fixed elevated temperature. The compression is released and, after the test piece has been allowed to recover at a standard laboratory tempe

35、rature or the elevated temperature for a specified time, the thickness of the test piece is again measured. 4 Apparatus 4.1 Compression assembly, consisting of compression plates, steel spacers and a clamping device. Typical assemblies are shown in Figure 1. 4.1.1 Compression plates, comprising a pa

36、ir of parallel, flat, highly polished chromium-plated steel or highly polished stainless-steel plates, between the faces of which the test piece is compressed. The finish of the surface of the compression plates shall be not worse than from the mean line of the profile (see ISO 4287). The plates sha

37、ll be sufficiently rigid to ensure that, with a test piece under load, no compression plate bends by more than ; of sufficient size to ensure that the whole of the test piece, when compressed between the plates, remains within the area of the plates. 4.1.2 Steel spacer(s), to provide the required co

38、mpression. The spacer(s) shall be of such size and shape that contact with the compressed test piece is avoided. The height of the spacer(s) shall be chosen so that the compression applied to the test piece isfor hardnesses below 80 IRHD;for hardnesses between 80 IRHD and 89 IRHD;for hardnesses of 9

39、0 IRHD and higher. 4.1.3 Clamping device: A simple screw device (see Figure 1) is adequate. 4.2 Oven, complying with the requirements specified in ISO 188:2007, method A or method B, and capable of maintaining the compression assembly with the test pieces at the test temperature within the tolerance

40、 limits specified in 6.2. NOTE Test results obtained with ovens for method A may be different may be different from those obtained with ovens for method B. The time to reach a steady-state temperature depends on the type of oven and the overall heat capacity of the compression assembly. To obtain co

41、mparable results in the case of an elevated test temperature and a test duration, it is necessary to reach the steady-state temperature within the specified tolerances in the interior of the test pieces in not more than . 4.3 Pair of tongs, for handling the test pieces. 4.4 Thickness gauge, with an

42、accuracy of (see ISO 23529:2004, 7.1), having a flat circular footin diameter and a flat solid base-plate and exerting a pressure of for solid rubber of hardness equal to or greater than 35 IRHD or a pressure of if the hardness is less than 35 IRHD. For comparative tests, the same dimensions of the

43、circular foot shall be used. NOTE When using a digital gauge, a resolution of is needed to obtain the required accuracy. Ra 0,4 m 0,01 mm (25 2) % (15 2) % (10 1) % 24 h 3h 0,01 mm 4mm 0,5 mm 22 kPa 5 kPa 10 kPa 2 kPa 0,001 mm SANS 10815-1:2009This standard may only be used and printed by approved s

44、ubscription and freemailing clients of the SABS.ISO 815-1:2008(E) ISO 2008 All rights reserved 3 After testing at elevated temperature, an unexpected deformation of the test piece is sometimes observed. More particularly, the two flat surfaces can be deformed, which complicates the thickness measure

45、ment. In this case, the diameter of the gauge used to measure the thickness should be chosen carefully to allow precise measurement. 4.5 Timing device, for measuring the recovery time, with a precision of . a) Example 1 b) Example 2 Key 1 test pieces 2 spacer 3 nut 4 upper plate 5 lower plate 6 part

46、 formed for clamping in a vice 7 locating pin 8s c r e w Figure 1 Examples of assemblies for the determination of compression set 1s SANS 10815-1:2009This standard may only be used and printed by approved subscription and freemailing clients of the SABS.ISO 815-1:2008(E) 4 ISO 2008 All rights reserv

47、ed 5 Test pieces 5.1 Dimensions The test pieces shall be one of two sizes, designated type A and type B: type A: a cylindrical disc of diameter and thickness ; type B: a cylindrical disc of diameter and thickness . These two types do not necessarily give the same values for compression set, and comp

48、arison of results obtained using test pieces of different sizes shall be avoided when comparing one compound with another. Type A test pieces are preferred for testing rubbers having low compression set, because of the greater accuracy attainable using these larger test pieces. Type B test pieces ar

49、e preferred when it is required to cut test pieces from products. In this case, the test pieces shall be taken as near to the centre of the product as possible, unless otherwise specified. When possible, the test piece shall be cut in such a way that its axis is parallel to the direction of compression of the product in service. 5.2 Preparation The test pieces shall be prepared by moulding each disc, whenever possible. Preparation by cutting out each disc or by laminating not more than thr