BS-903-A44-1995 ISO-1431-2-1994.pdf
《BS-903-A44-1995 ISO-1431-2-1994.pdf》由会员分享,可在线阅读,更多相关《BS-903-A44-1995 ISO-1431-2-1994.pdf(16页珍藏版)》请在三一文库上搜索。
1、BRITISH STANDARD BS 903-A44: 1995 ISO 1431-2: 1994 Physical testing of rubber Part A44: Method for determination of resistance to ozone cracking (dynamic strain test) Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 04:56:58 GMT+00:00 2006, Uncontrolled Copy, (c)
2、 BSI BS 903-A44:1995 This British Standard, having been prepared under the direction of the Materials and Chemicals Sector Board (I/-), was published under the authority of the Standards Board and comes into effect on 15 February 1995 BSI 04-1999 First published December 1983 Second edition February
3、 1995 The following BSI references relate to the work on this standard: Committee reference PRI/22 Draft for comment 90/47550 DC ISBN 0 580 23655 2 Committees responsible for this British Standard The preparation of this British Standard was entrusted to Technical Committee PRI/22, Physical testing
4、of rubber, upon which the following bodies were represented: British Railways Board British Rubber Manufacturers Association Ltd. GAMBICA (BEAMA Ltd.) Malaysian Rubber Producers Research Association Ministry of Defence RAPRA Technology Ltd. SATRA Footwear Technology Centre Coopted member Amendments
5、issued since publication Amd. No.DateComments Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 04:56:58 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 903-A44:1995 BSI 04-1999i Contents Page Committees responsibleInside front cover National forewordii 1Scope1 2Nor
6、mative references1 3Definition1 4Principle1 5Apparatus1 6Test piece3 7Conditioning4 8Test conditions4 9Test procedure5 10Expression of results6 11Test report6 Annex A (informative) Explanatory notes7 Figure 1 Schematic diagram of the apparatus2 Figure 2 Dumb-bell test piece5 List of referencesInside
7、 back cover Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 04:56:58 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 903-A44:1995 ii BSI 04-1999 National foreword This Part of BS 903 has been prepared by Technical Committee PRI/22. This revision of Part A44 is ide
8、ntical with ISO 1431-2:1994 Rubber, vulcanized or thermoplastic Resistance to ozone cracking Part 2: Dynamic strain test, published by the International Organization for Standardization (ISO). This Part of BS 903 supersedes BS 903-A44:1983 which is withdrawn. The major changes incorporated in this r
9、evision are as follows. a) Provision has been made for conducting tests, if required, at a velocity of flow of ozonized air of 600 mm/s 100 mm/s (see 5.5). b) An alternative dumb-bell test piece has been added (see 6.3). c) The maximum elongations of (40 2) % and (60 2) % have been added (see 8.4).
10、WARNINGAttention is drawn to the warning in clause 5. The recommendation that 10 pphm be regarded as an absolute maximum concentration in the surrounding atmosphere is in accordance with the value given for long term exposure (8 h TWA, Time Weighted Average, reference period) in Guidance Note EH 40/
11、90 Occupational exposure limits published by the Health and Safety Executive, i.e. 0.1 ppm. NOTEGuidance Note EH 40/90 expresses occupational exposure limits in parts of ozone per million parts of air by volume (ppm). Units of pphm are used throughout this standard since this is normal practice in t
12、he rubber industry. Attention is also drawn to Guidance Note EH 38/83 Ozone health hazards and precautionary measures. It is intended that the international standard for the reference method for estimating the ozone concentration (ISO 1431-3, as referred to in clause 1 and in 5.4), at present in pre
13、paration, will be implemented as a British Standard as BS 903-A45. Until the reference method for estimating the ozone concentration is published any suitable titrimetric or instrumental method may be used although it will not be possible to calibrate such methods against the reference method. It is
14、 emphasized that details of the method of estimation of ozone concentration should be included in the test report (see item c) 1) clause 11). Additional information. In UK practice, the standard temperature is 23 C 2 C (see clause 7) and is commonly referred to as the “standard laboratory temperatur
15、e”. Cross-references International standardCorresponding British Standard BS 903 Physical testing of rubber ISO 37:1994Part A2:1995 Determination of tensile stress-strain properties (Identical) ISO 471:1983Part A35:1985 Temperatures, humidities and times for conditioning and testing of test pieces (
16、Identical) ISO 1431-1:1989Part A43:1990 Determination of resistance to ozone cracking (static strain test) (Identical) ISO 4661-1:1993Part A36:1995 Preparation of samples and test pieces (Identical) Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 04:56:58 GMT+00
17、:00 2006, Uncontrolled Copy, (c) BSI BS 903-A44:1995 BSI 04-1999iii A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immuni
18、ty from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i to iv, pages 1 to 8, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the am
19、endment table on the inside front cover. Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 04:56:58 GMT+00:00 2006, Uncontrolled Copy, (c) BSI iv blank Licensed Copy: London South Bank University, London South Bank University, Fri Dec 08 04:56:58 GMT+00:00 2006, U
20、ncontrolled Copy, (c) BSI ISO 1431-2:1994(E) BSI 04-19991 1 Scope This part of ISO 1431 specifies a method intended for use in estimating the resistance of vulcanized or thermoplastic rubbers to cracking when exposed, under dynamic tensile strain, to air containing a definite concentration of ozone
21、and at a definite temperature in circumstances that exclude the effects of direct light. Great caution is necessary in attempting to relate standard test results to service performance since the relative ozone resistance of different rubbers can vary markedly depending on the conditions, especially
22、ozone concentration and temperature. In addition, tests are carried out on thin test pieces deformed in tension and the significance of attack for articles in service may be quite different owing to the effects of size and of the type and magnitude of deformation. Explanatory notes on the nature of
23、ozone cracking are given in informative Annex A. Methods for determining resistance to ozone cracking under static strain conditions are specified in ISO 1431-1. A reference method for estimating the ozone concentration will form the subject of ISO 1431-3. 2 Normative references The following standa
24、rds contain provisions which, through reference in this text, constitute provisions of this part of ISO 1431. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this part of ISO 1431 are encouraged to investigate t
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- BS-903-A44-1995 ISO-1431-2-1994 BS 903 A44 1995 ISO 1431 1994
链接地址:https://www.31doc.com/p-3737951.html