SANS 51-2008 Plastics piping and ducting systems - Injection-moulded thermoplastics fittings - Methods for visually assessing the effects of heating《塑料管道及管道系统 注射成型热塑配件 加热影响视觉评估方法》.pdf

《SANS 51-2008 Plastics piping and ducting systems - Injection-moulded thermoplastics fittings - Methods for visually assessing the effects of heating《塑料管道及管道系统 注射成型热塑配件 加热影响视觉评估方法》.pdf》由会员分享，可在线阅读，更多相关《SANS 51-2008 Plastics piping and ducting systems - Injection-moulded thermoplastics fittings - Methods for visually assessing the effects of heating《塑料管道及管道系统 注射成型热塑配件 加热影响视觉评估方法》.pdf（13页珍藏版）》请在麦多课文档分享上搜索。

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 978-0-626-21935-2 SANS 51:2008 Edition 2 ISO 580:2005 Edition 3SOUTH AFRICAN NATIONAL STANDARD Plastics piping and ducting systems Injection-moulded

4、 thermoplastics fittings Methods for visually assessing the effects of heating This national standard is the identical implementation of ISO 580:2005 and is adopted with the permission of the International Organization for Standardization. Published by SABS Standards Division 1 Dr Lategan Road Groen

5、kloof Private 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 51:2008 Edition 2 ISO 580:2005 Edition 3 Table of changes Change No. Date Scope National for

6、eword This South African standard was approved by National Committee SABS SC 138H, Water and sanitation Equipment and systems Plastics pipes and fittings, in accordance with procedures of the SABS Standards Division, in compliance with annex 3 of the WTO/TBT agreement. This SANS document was publish

7、ed in September 2008. This SANS document supersedes SABS ISO 580:1990 (edition 1). This standard may only be used and printed by approved subscription and freemailing clients of the SABS. Reference number ISO 580:2005(E) ISO 2005INTERNATIONAL STANDARD ISO 580 Third edition 2005-02-15 Plastics piping

8、 and ducting systems Injection-moulded thermoplastics fittings Methods for visually assessing the effects of heating Systmes de canalisations et de gaines en plastiques Raccords thermoplastiques mouls par injection Mthodes dessai pour estimer visuellement les effets de la chaleur SANS 51:2008This st

9、andard may only be used and printed by approved subscription and freemailing clients of the SABS.ISO 580:2005(E) PDF disclaimer This PDF file may contain embedded typefaces. In accordance with Adobes licensing policy, this file may be printed or viewed but shall not be edited unless the typefaces wh

10、ich are embedded are licensed to and installed on the computer performing the editing. In downloading this file, parties accept therein the responsibility of not infringing Adobes licensing policy. The ISO Central Secretariat accepts no liability in this area. Adobe is a trademark of Adobe Systems I

11、ncorporated. Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In the unlikely event

12、 that a problem relating to it is found, please inform the Central Secretariat at the address given below. ISO 2005 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

13、 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 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

14、 ii ISO 2005 All rights reservedSANS 51:2008This standard may only be used and printed by approved subscription and freemailing clients of the SABS.ISO 580:2005(E) ISO 2005 All rights reserved iiiForeword ISO (the International Organization for Standardization) is a worldwide federation of national

15、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 represented on that committee. International

16、 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 drafted in accordance with the rules g

17、iven 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 Standard requires approval by at leas

18、t 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 580 was prepared by Technical Committee ISO/TC 138, P

19、lastics pipes, fittings and valves for the transport of fluids, Subcommittee SC 5, General properties of pipes, fittings and valves of plastic materials and their accessories Test methods and basic specifications. This third edition cancels and replaces the second edition (ISO 580:1990), which has b

20、een technically revised. SANS 51:2008This standard may only be used and printed by approved subscription and freemailing clients of the SABS.ISO 580:2005(E) iv ISO 2005 All rights reservedIntroduction The test for determination of the resistance to heat according to the two test methods specified in

21、 this International Standard is applicable for distinguishing between properly and improperly moulded thermoplastics pipe fittings. It can be used to determine whether cold slugs (pieces of material that enter the mould at a temperature significantly lower than the rest of the mass) or unfused areas

22、 are present, reveal cavities and porosity, determine the amount of moulded-in stress produced by the moulding process, reveal contamination, and show the integrity of the fusion line. A stress-free part will generally have better properties and higher strength than parts with a higher degree of res

23、idual stress and will generally be less reactive when exposed to chemicals. By placing moulded fittings in a heated medium (air or liquid) at elevated temperature for a period of time dependant on their wall thickness, it is possible to detect internal stress. Since the stresses start to be released

24、 as soon as the material passes to the rubbery state, it is only necessary to maintain the moulded pieces at a higher temperature for a defined period of time. NOTE Injection-moulded fittings can be made by a number of techniques, whereby the material is injected into the mould cavity. These include

25、 single- or multi-point injection, diaphragm gating and ring gating. The technique used in the manufacture of mouldings will affect the way in which they are assessed. SANS 51:2008This standard may only be used and printed by approved subscription and freemailing clients of the SABS.INTERNATIONAL ST

26、ANDARD ISO 580:2005(E) ISO 2005 All rights reserved 1Plastics piping and ducting systems Injection-moulded thermoplastics fittings Methods for visually assessing the effects of heating 1 Scope This International Standard specifies two methods for assessing the effects of heating on injection-moulded

27、 thermoplastics pipe fittings method A, using an air oven, and method B, using a liquid bath. In case of disagreement, method A is the reference method. This International Standard is applicable to cement-welded fittings as well as to flanged fittings and fittings incorporating elastomeric seals and

28、 to fittings consisting of the assembly of several moulded parts (e.g. union connectors). It is applicable to both pressure and non-pressure fittings. 2 Principle Complete mouldings are subjected to an elevated specified temperature in an air-circulating oven or a liquid bath for a given period of t

29、ime, depending upon the wall thickness of the fitting and the material being moulded. The surfaces of the moulding are examined before and after heating, and any cracks, blisters, delaminations or opening of fusion lines are measured and expressed as a percentage of the wall thickness. 3 Test parame

30、ters The following test parameters are specified by the subclauses referenced as follows and in Table 1 for the particular material used in the manufacturer of the fitting, unless the referring standard (a standard making reference to this International Standard in its own provisions) or regulations

31、 specify otherwise: a) the test temperature, T (see 4.1.1 and 4.3); b) the number of test pieces (see 4.2.2); c) the heating time, t (see 4.3.3); d) the test method to be used and, for method B (liquid bath) only, the test liquid. e) the acceptable limits for the occurrence or dimensions of any crac

32、ks or other features found (see 4.3.6). SANS 51:2008This standard may only be used and printed by approved subscription and freemailing clients of the SABS.ISO 580:2005(E) 2 ISO 2005 All rights reservedUnless otherwise specified in the referring standard or regulations, the test parameters shall be

33、in accordance with Table 1. Table 1 Test parameters to be used in absence of guidance in the referring standard Heating time Material Temperature T 2 C Mean wall thickness e mmm Duration t min ABS 150 PE 110 PP PVC-U PVC-C SAN+PVC 150 e mu 3 3 e mu 10 10 e mu 20 20 e mu 30 30 e mu 40 40 e m15 30 60

34、140 220 240 4 Method A 4.1 Apparatus 4.1.1 Air-circulating oven, thermostatically controlled, equipped with a thermostat so that the temperature of the working zone can be maintained at the prescribed test temperature throughout the test and of sufficient heating capacity to enable the test temperat

35、ure to be regained within 15 min of insertion of the test pieces. 4.1.2 Thermometer, graduated in 0,5 C. Or a type “T” thermocouple with a resolution of 0,1 C and an accuracy of at least 0,8 C. 4.2 Test pieces 4.2.1 Preparation After removing any runners, take the complete mouldings as test pieces.

36、If the fitting incorporates an elastomeric sealing ring, remove the ring before testing. In the case of fittings assembled from more than one element, separate the components and test them out of contact with each other. 4.2.2 Number The number of test pieces shall be as specified in the product sta

37、ndard. In the absence of any information on the number of test pieces, use at least three pieces. 4.3 Procedure 4.3.1 Set the oven temperature (4.1.1) at the test temperature (T 2) C in accordance with the product standard or Table 1. 4.3.2 Put the test pieces in the oven and arrange them so that th

38、ey are standing on one side of their sockets wherever possible, avoiding contact with another test piece or the sides of the oven. SANS 51:2008This standard may only be used and printed by approved subscription and freemailing clients of the SABS.ISO 580:2005(E) ISO 2005 All rights reserved 34.3.3 L

39、eave the test pieces in the oven until the oven returns to the test temperature (T 2) C and for a further period, t, dependent on the mean wall thickness, e m , of the thickest part of the test piece(s) in accordance with the product standard or Table 1. 4.3.4 Remove the test pieces from the oven, t

40、aking care not to deform or damage them. 4.3.5 Cut the test pieces with a sharp knife or razor blade while they are still hot, to enable the dimensions of cracks, blisters, delaminations and weld-line openings, if any, to be measured as required. Allow the test pieces and/or parts therefrom to cool

41、in air until they can be handled without deformation. If not otherwise specified in the referring standard, the following number of cuts should be made: for cylindrical components of d nu 160 mm, not less than two cuts equally spaced around the periphery of the mouth of each socket or spigot of the

42、component; for cylindrical components of d n 160 mm, not less than four cuts equally spaced around the periphery of the mouth of each socket or spigot of the component. For d n , see Figure 1. 4.3.6 Examine each test piece for, and record, any surface changes, such as cracks, delaminations and weld-

43、line openings as well as changes inside the wall, e.g. blisters, and in the gating area. Determine the extent of such defects in the gating area as a percentage of the wall thickness as follows. a) For sprue-gated mouldings (see Figure 1): around the injection point(s) within a radius as specified i

44、n the referring standard. In the absence of any information in the referring standard, use R = 0,3d nwith a maximum value of 50 mm. b) For ring- or diaphragm-gated mouldings (see Figure 1): within a length, L, of the cylindrical portion of the gating area as specified in the referring standard or, i

45、n absence of any information, within a length L = 0,3d n . In the case of cracks running through the whole wall thickness of the gating area, determine also the length of the crack. c) For mouldings containing fusion lines, determine the widest and deepest part(s) of any open part of the fusion line

46、. d) For all other parts of the moulding beyond the gating area, examine the surface for any change, such as cracks, blisters, and delaminations of the wall. If not specified in the referring standard, the specifications given in Annex A should be used for the examination of a test piece. SANS 51:20

47、08This standard may only be used and printed by approved subscription and freemailing clients of the SABS.ISO 580:2005(E) 4 ISO 2005 All rights reserveda) Sprue-gate b) Diaphragm-gate c) Ring-gate Figure 1 Injection gating areas 5 Method B 5.1 Apparatus 5.1.1 Heating bath, thermostatically controlle

48、d, at the prescribed test temperature, (T 2) C. The volume and agitation of the bath shall be such that the temperature remains within the specified temperature range when the test pieces are immersed. The liquid chosen shall be stable at the specified temperature and shall not otherwise affect the

49、test piece. It shall be ensured that the liquid does not cause any safety or health risks. NOTE 1 Glycerine, glycol, mineral oil free from aromatic hydrocarbons, or a solution of calcium chloride may be suitable, depending upon which of the materials covered by this method is under test. For example, all these liquids are suitable for PVC-U, but the use of glycols is not appropriate for ABS fittings, for which the selection of an appropriate mineral oil is preferable. NOTE 2 Attention is dr