BS ISO 8513-2016 Plastics piping systems Glass-reinforced thermosetting plastics (GRP) pipes Test methods for the determination of the initial longitudinal tensile strengt.pdf

1、BSI Standards Publication BS ISO 8513:2016 Plastics piping systems Glass-reinforced thermosetting plastics (GRP) pipes Test methods for the determination of the initial longitudinal tensile strengthBS ISO 8513:2016 BRITISH STANDARD National foreword This British Standard is the UK implementation of

2、ISO 8513:2016. It supersedes BS ISO 8513:2014 which is withdrawn. The UK participation in its preparation was entrusted to Technical Committee PRI/88/2, Plastics piping for pressure applications. A list of organizations represented on this committee can be obtained on request to its secretary. This

3、publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2016. Published by BSI Standards Limited 2016 ISBN 978 0 580 87693 6 ICS 23.040.20 Compliance with a British Standard cannot confer

4、 immunity from legal obligations. This British Standard was published under the authority of the Standards Policy and Strategy Committee on 29 February 2016. Amendments/corrigenda issued since publication Date T e x t a f f e c t e dBS ISO 8513:2016 ISO 2016 Plastics piping systems Glass- reinforced

5、 thermosetting plastics (GRP) pipes Test methods for the determination of the initial longitudinal tensile strength Systmes de canalisations en plastiques Tubes en plastiques thermodurcissables renforcs de verre (PRV) Mthodes dessai pour la dtermination de la force en traction longitudinale INTERNAT

6、IONAL STANDARD ISO 8513 Third edition 2016-02-01 Reference number ISO 8513:2016(E)BS ISO 8513:2016ISO 8513:2016(E)ii ISO 2016 All rights reserved COPYRIGHT PROTECTED DOCUMENT ISO 2016, Published in Switzerland All rights reserved. Unless otherwise specified, no part of this publication may be reprod

7、uced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester.

8、 ISO copyright office Ch. de Blandonnet 8 CP 401 CH-1214 Vernier, Geneva, Switzerland Tel. +41 22 749 01 11 Fax +41 22 749 09 47 copyrightiso.org www.iso.orgBS ISO 8513:2016ISO 8513:2016(E)Foreword iv Introduction v 1 Scope . 1 2 T erms and definitions . 1 3 Principle 2 4 Apparatus . 3 5 Test pieces

9、 . 3 5.1 General . 3 5.2 Strip test piece (method A) 4 5.2.1 Shape 4 5.2.2 Dimensions . 4 5.2.3 Use of built-up ends 6 5.3 Pipe section test pieces (method B) . 6 5.4 Number of test pieces . 6 6 Conditioning 6 7 Test temperature 6 8 Procedure (methods A and B) 7 9 Calculation 7 9.1 For strip test pi

10、eces (method A) 7 9.2 For pipe test pieces (method B) . 7 10 Test report . 8 Annex A (informative) Det ermination of longitudinal pr operties for helicall y filament- wound thin wall pipe 9 Bibliography .11 ISO 2016 All rights reserved iii Contents PageBS ISO 8513:2016ISO 8513:2016(E) Foreword ISO (

11、the International Organization for Standardization) is 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 commi

12、ttee has been established has the right to be represented 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 electrotec

13、hnical standardization. The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafte

14、d in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives). 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 righ

15、ts. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents). Any trade name used in this document is information given for the convenience of users and does not constit

16、ute an endorsement. For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT) see the following URL: Foreword - Supplementary information. The co

17、mmittee responsible for this document is ISO/TC 138, Plastics pipes, fittings and valves for the transport of fluids, Subcommittee SC 6, Reinforced plastics pipes and fittings for all applications. This third edition cancels and replaces the second edition (ISO 8513:2014) which has been technically

18、revised.iv ISO 2016 All rights reservedBS ISO 8513:2016ISO 8513:2016(E) Introduction Although this International Standard was revised in 2014, it was found necessary to again revise to correct several small errors in presentation and to revise the allowable testing speed (crosshead movement) range.

19、A review of ISO testing standards for glass-reinforced thermosetting plastics (GRP) materials and the results of a recent testing program indicated that a testing speed of 2 mm/min to 5 mm/min is more appropriate. Also, evidence was presented that method C, the plate method, lead to results that wer

20、e frequently from shear failures rather than tensile failures and lead to a falsely high prediction of Longitudinal Tensile Strength. Method C has been removed from this edition. Also, the term “Apparent” was removed from the title as it seemed to have no clear meaning. ISO 2016 All rights reserved

21、vBS ISO 8513:2016BS ISO 8513:2016Plastics piping systems Glass-reinforced thermosetting plastics (GRP) pipes Test methods for the determination of the initial longitudinal tensile strength 1 Scope This International Standard specifies two test methods for determining the longitudinal tensile propert

22、ies of glass-reinforced thermosetting plastics (GRP) pipes. The properties which can be determined are the longitudinal tensile strength, and the percentage ultimate elongation. Method A uses, for the test piece(s), a longitudinal strip cut from a pipe. Method B uses a specified length of the full c

23、ross-section of the pipe. Method A is applicable to pipes with a nominal size of DN 50 or greater with circumferentially wound filaments, with or without chopped glass and/or woven rovings and/or fillers, and to centrifugally cast pipes. It is applicable to pipes with helically wound filaments with

24、a nominal size of DN 200 or greater. Method B is applicable to all types of GRP pipe. It is usually used for pipes with a nominal size up to and including DN 150. Results from one method are not necessarily equal to the results derived from any of the alternative methods. However, all methods have e

25、qual validity. Annex A describes additional considerations for method B that have been found useful for the testing of thin-walled helically wound pipes and can be used to supplement the basic text. NOTE This International Standard does not address the determination of longitudinal tensile modulus.

26、Due to the multi-layer construction of many GRP pipes, the accurate measurement of strain, necessary for modulus determination, can be very difficult. If it is desired to determine longitudinal modulus, see ISO 527-4 and/or ISO 527-5. 2 T erms a nd definiti ons For the purposes of this document, the

27、 following terms and definitions apply. 2.1 helical wound refers to filament-wound pipes made with a balanced winding angle Note 1 to entry: Sometimes called cross wound. 2.2 longitudinal tensile strength LA * LB * maximum tensile force in the longitudinal direction per unit mean circumference at fa

28、ilure Note 1 to entry: It is expressed in newtons per millimetre of the circumference (N/mm). Note 2 to entry: The subscripts A and B denote the method of test used. INTERNATIONAL ST ANDARD ISO 8513:2016(E) ISO 2016 All rights reserved 1BS ISO 8513:2016ISO 8513:2016(E) 2.3 mean circumference circumf

29、erence corresponding to the mean diameter multiplied by ( 3,141 6) Note 1 to entry: It is expressed in millimetres. 2.4 mean diameter d m diameter of the circle corresponding with the middle of the pipe wall cross-section Note 1 to entry: It is given by any of the following: a) the average of the ex

30、ternal diameter of the pipe minus the average of the wall thickness; b) the external circumference of the pipe divided by ( 3,141 6) minus the average of the wall thickness; c) the average of the internal diameter of the pipe plus the average of the wall thickness. Note 2 to entry: It is expressed i

31、n millimetres. 2.5 ultimate longitudinal tensile stress L,ULT maximum longitudinal tensile force per unit cross-sectional area at failure Note 1 to entry: It is expressed in newtons per square millimetre (N/mm). 2.6 ultimate elongation L elongation coincident with the ultimate longitudinal tensile s

32、tress Note 1 to entry: For the purposes of this International Standard, the measurement of elongation is limited to measurement of the movement of the tensile testing machine cross-heads. Note 2 to entry: It is expressed as a percentage of an initial gauge length or free length of a test piece. 3 Pr

33、inciple Test pieces comprising either strips cut longitudinally from a pipe wall segment (method A) or a specified length of pipe (method B) are subjected to extension in the longitudinal direction at a constant speed such that fracture occurs within a specified time. The tensile properties are dete

34、rmined using the initial dimensions of the test piece, the tensile force, and the cross-head movement. NOTE It is assumed that the following test parameters are set by the standard making reference to this International Standard: a) the methods to be used, i.e. method A or method B; b) the number of

35、 test pieces (see 5.4); c) if applicable, the requirements for conditioning, e.g. temperature, humidity, time, and associated tolerances (see Clause 6); d) the test temperature and its tolerance (see Clause 7); e) the properties to be measured (see Clause 8).2 ISO 2016 All rights reservedBS ISO 8513

36、:2016ISO 8513:2016(E) 4 Apparatus 4.1 Tensile-testing machine, of the constant rate of cross-head movement type, incorporating the following features: a) a fixed part, fitted with a grip to hold one end of the test piece without permitting any longitudinal movement thereof, and a moveable part, inco

37、rporating a grip to hold the other end of the test piece during extension the fixed and moving parts and their associated grips (see 4.2) shall enable the test piece to be aligned when a force is applied so that its longitudinal axis coincides with the direction of this force; b) a drive mechanism,

38、capable of imparting a constant speed (see 8.3) to the moving part; c) a force indicator, capable of measuring the force applied to a test piece which is held in the grips (the mechanism shall be free from significant inertia lag at the necessary speed of testing and shall indicate or record force,

39、or consequent stress, with an accuracy of within 1 % of the value to be measured); d) a means to measure the cross-head movement as a function of the applied load. 4.2 Grips, for holding the test piece. Each of the two grips shall be capable of holding one end of the test piece without slip or crush

40、ing to an extent that will affect the results obtained. Grips which tighten automatically might be suitable. Typical grips for a pipe section test piece (see 5.3) are shown in Figure 1. Key 1 mandrel 2 segmented grips 3 sleeve 4 reinforcing band 5 test piece Figure 1 Typical grips for a pipe section

41、 test piece (method B) 4.3 Dimension measurement devices, capable of measuring the necessary dimensions of the test piece (e.g. length, width, wall thickness) to an accuracy of half the accuracy required in Clause 8 for measurements, e.g. a measuring accuracy of 0,1 mm requires a device accuracy of

42、0,05 mm. 5 Test pieces 5.1 General The test piece shall be a strip or dumbbell conforming to 5.2, or a pipe section conforming to 5.3. ISO 2016 All rights reserved 3BS ISO 8513:2016ISO 8513:2016(E) The test piece shall be obtained in such a way that it is not damaged. The test piece width guidelines

43、 might, of necessity, need to be altered for thick wall pipes to smaller values to reflect the testing machine capacity. This is due to some GRP pipes being made in very high thickness to address high pressure and large diameter applications. The testing of such narrower samples will lead to a more

44、conservative indication of strength for thick wall pipes. For thick wall test pieces, it might also be necessary to clamp the specimen on the cut cross-section sides to allow the specimen to fit into the testing grips. For pipes with a layered wall construction, it might also be necessary to reinfor

45、ce the gripped ends to obtain a more even distribution of tensile force. For pipes reinforced in the axial direction with tapes, fabrics, or mats of a fixed width, it might be necessary to increase the test sample length to ensure that a cross-section with the minimum number of layers of reinforceme

46、nt (the apparent lowest strength area) falls within the gauge length. NOTE The test pieces for method A can be cut from a ring previously used for the determination of the initial specific ring stiffness. 5.2 Strip test piece (method A) 5.2.1 Shape Each test piece shall be a strip cut in the longitu

47、dinal direction of the pipe and either shaped to the dimensions of the applicable dumbbell as shown in Figure 2 or a parallel-sided (rectangular) test piece as shown in Figure 3. 5.2.2 Dimensions 5.2.2.1 Length The length, l, of the test piece shall be (300 15) mm (see Figure 2 and Figure 3). 5.2.2.

48、2 Shaped strip The gauge length, l G , of the test piece shall be as follows (see Figure 2): 100 mm l G 150 mm (1) The radius, R, shall be machined to conform to the following limits (see Figure 2): 50 mm R 70 mm (2) The width, b G , of the test piece within the gauge length shall conform to the fol

49、lowing requirements (see Figure 2 and 5.2.1): b G= (10 1) mm for DN 150 (3) b G= (25 1) mm for DN 150 (4) The total width, b, of the test piece shall conform to the following requirements (see Figure 2): b = (18 2) mm for DN 150 (5)4 ISO 2016 All rights reservedBS ISO 8513:2016ISO 8513:2016(E) b = (40 2) mm for DN 150 (6) The above width guidelines might need to be reduced to accommodate thick wall pipes (see 5.1). Key 1 centroid of gauge length cross-section 2 ends built up with pla