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 978-0-626-20823-3 SANS 5791:2008Edition 2 SOUTH AFRICAN NATIONAL STANDARD Resistance of saucers and plates to chipping Published by Standards South
4、Africa 1 dr lategan road groenkloof private bag x191 pretoria 0001 tel: 012 428 7911 fax: 012 344 1568 international code + 27 12 www.stansa.co.za Standards South Africa SANS 5791:2008 Edition 2 Table of changes Change No. Date Scope Foreword This South African standard was approved by National Comm
5、ittee StanSA TC 5140.05, Crockery, in accordance with procedures of Standards South Africa, in compliance with annex 3 of the WTO/TBT agreement. This document was published in February 2008. This document supersedes SABS SM 791:1974 (edition 1). SANS 5791:2008 Edition 2 1 Resistance of saucers and p
6、lates to chipping 1 Scope This standard specifies a method for the determination of the resistance of saucers and plates to chipping. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies
7、 For undated references, the latest edition of the referenced document (including any amendments) applies. Information on currently valid national and international standards can be obtained from Standards South Africa. SANS 6508-1/ISO 6508-1, Metallic materials Rockwell hardness test Part 1: Test
8、method (scales A,B,C,D,E,F,G,H,K,N,T). SANS 6508-2/ISO 6508-2, Metallic materials Rockwell hardness test Part 2: Verification and calibration of testing machines (scales A,B,C,D,E,F,G,H,K,N,T). SANS 5790, Impact strength of cups, saucers, and plates. 3 Apparatus Impact strength test apparatus, as sp
9、ecified in SANS 5790, but fitted with a 170 g hammer and a 170 g dial. The striking face of the hammer shall have a Rockwell C hardness of 60 3, determined in accordace with SANS 6508-1 and SANS 6508-2. 4 Sampling Take a laboratory sample as specified in the relevant product standard. Where no stand
10、ard exists, take the laboratory sample as agreed upon between the test laboratory and the manufacturer to ensure a reasonable and acceptable reliability at a reasonable and acceptable confidence level. 5 Procedure 5.1 So position the test specimen (on its foot) in the V formed by the V-blocks of the
11、 apparatus that only the upper edge of the specimen is in contact with the V-blocks and that, when the hammer hangs perpendicular, the centre of its striking face just touches the edge of the test specimen. 5.2 Subject the specimen to a series of hammer blows, beginning with a blow of energy 0,04 J
12、and increasing the energy of each successive blow by an increment of 0,01 J until the energy reaches 0,14 J and then by increments of 0,02 J. SANS 5791:2008 Edition 2 2 5.3 Continue until a crack develops in the body or a part of the body breaks off. Do not regard the development of crazes or chippi
13、ng of glaze as a failure. Record the maximum impact withstood before failure occured. 5.4 Repeat the procedure on two points on the edge of the specimen that are so spaced that the distances between the three points tested are approximately equal and that neither coincides with a point that was in c
14、ontact with a V-block in an earlier test. 5.5 Record the mean of the three results as the resistance to chipping of the test specimen. 6 Test report Report the following information: a) all the data needed to identify the laboratory sample tested; b) confirmation that the test was carried out in accordance with this standard; c) any deviation from this standard; d) the maximum impact, in joules, withstood before failure occurred; and e) the mean of the three results, in joules, as the resistance to chipping of the specimen. Standards South Africa
