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 978-0-626-21853-9 SANS 5870:2008Edition 2SOUTH AFRICAN NATIONAL STANDARD Hardness of vulcanized rubbers of hardness 30-95 IRH degrees Published by S
4、ABS Standards Division 1 Dr Lategan Road Groenkloof Private Bag X191 Pretoria 0001 Tel: +27 12 428 7911 Fax: +27 12 344 1568 www.sabs.co.za SABS SANS 5870:2008 Edition 2 Table of changes Change No. Date Scope Foreword This South African standard was approved by National Committee SABS TC 45, Rubber
5、and rubber products, in accordance with procedures of the SABS Standards Division, in compliance with annex 3 of the WTO/TBT agreement. This document was published in November 2008. This document supersedes SABS SM 870:1976 (first edition). This document is based on ISO 48. SANS 5870:2008 Edition 2
6、1 Contents Page Foreword 1 Scope . 3 2 Normative references . 3 3 Apparatus . 3 3.1 Hardness testing apparatus 3 3.2 A thickness gauge . 4 3.3 A stopwatch . 4 4 Preparation of test specimens 4 4.1 General 4 4.2 For nominal test . 4 4.3 For micro test 4 5 Procedure . 4 6 Calculation . 5 SANS 5870:200
7、8 Edition 2 2 This page is intentionally left blank SANS 5870:2008 Edition 2 3 Hardness of vulcanized rubbers of hardness 30-95 IRH degrees 1 Scope This standard specifies the procedure for testing the hardness of vulcanized rubbers of hardness 30-95 IRH degrees. 2 Normative references The following
8、 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 documents (including any amendments) applies. Information on currently valid national and international sta
9、ndards can be obtained from the SABS Standards Division. SANS 5867 (SABS SM 867), Preparation of samples of vulcanized rubbers for testing. SANS 5868 (SABS SM 868), Conditioning of vulcanized rubbers. 3 Apparatus 3.1 Hardness testing apparatus A normal hardness testing apparatus or a micro-hardness
10、testing apparatus that has in both cases the following essential components: a) A vertical plunger that has, on the lower end, a rigid ball or spherical surface of the appropriate diameter given in column 2 of table 1, and through which the appropriate contact and indenting forces given in columns 3
11、 and 4 of table 1 can be applied. b) Means for applying the relevant forces to the plunger. c) A device capable of measuring the increase in depth of indentation of the plunger caused by the indenting force, and calibrated from (0-100) IRH degrees. d) A locating ring that is concentric with the plun
12、ger, has the appropriate outside and hole diameters given in column 2 of table 1 and, when resting on the surface of the specimen during a test, exerts on the specimen the appropriate force given in column 6. e) An anti-friction vibrator. f) A flat rigid base plate. SANS 5870:2008 Edition 2 4 Table
13、1 Forces and dimensions of hardness testing apparatus 1 2 3 4 5 6 Force on ball in N Type of apparatus Diameter in mm Contact Indenting Total Force on ring in N Normal ball 2,38 0.01 ring 20 1 hole 6 1 0,30 0,02 5,23 0,01 5,53 0,03 8,3 1,5 Micro Ball 0,395 0,005 Ring 3,35 0,15 Hole 1,00 0,15 (8,3 0,
14、5) 103(145 0,5) 103(153 1) 103(235 30) 1033.2 A thickness gauge capable of measuring accurately to 0,01 mm. 3.3 A stopwatch. 4 Preparation of test specimens 4.1 General From each sample after, when relevant, preparing it in accordance with SANS 5867, prepare five discs of the dimensions given in 4.2
15、 or 4.3 as relevant and having upper and lower surfaces that are flat, smooth, and parallel to one another. Condition the specimens in accordance with SANS 5868. 4.2 For normal test Use discs of thickness at least 4 mm and preferably between 8 mm and 10 mm using not more than 2 layers to achieve thi
16、s thickness and of diameter at least 25 mm. 4.3 For micro test Use discs of thickness 2 mm 0,5 mm and having a diameter of at least 5 mm. 5 Procedure 5.1 Lightly dust the upper and lower surfaces of the test specimens with talcum powder. 5.2 Place the specimens in turn on the flat rigid base plate b
17、elow the plunger with the upper surface facing the plunger and so that the plunger will contact the centre of the specimen. 5.3 Lower the locating ring on to the specimen and apply the appropriate contact force to the plunger. 5.4 Maintain this force for 5 s - 10 s, then immediately set the recordin
18、g device to read 100 IRH degrees, increase the applied force to the appropriate total given in column 5 of table 1, and after 30 s record the hardness value obtained. SANS 5870:2008 Edition 2 5 6 Calculation Calculate and record as the hardness of the test sample the average of the five values obtained. SABS
