1、BRITISH STANDARDBS EN ISO 13478:2007Thermoplastics pipes for the conveyance of fluids Determination of resistance to rapid crack propagation (RCP) Full-scale test (FST)ICS 23.040.20g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g3
2、6g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS EN ISO 13478:2007This British Standard was published under the authority of the Standards Policy and Strategy Committee on 29 February 2008 BSI 2008ISBN 978 0 580 55226 7National forewordThis British Standard is the
3、UK implementation of EN ISO 13478:2007. It supersedes BS EN ISO 13478:1997 which is withdrawn. The UK participation in its preparation was entrusted by Technical Committee PRI/88, Plastics piping systems, to Subcommittee PRI/88/4, Test methods.A list of organizations represented on this committee ca
4、n be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.Amendments/corrigenda issued since pub
5、licationDate CommentsEUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN ISO 13478August 2007ICS 23.040.20 Supersedes EN ISO 13478:1997 English VersionThermoplastics pipes for the conveyance of fluids -Determination of resistance to rapid crack propagation (RCP) -Full-scale test (FST) (ISO 13478:2007)
6、Tubes en matires thermoplastiques pour le transport desfluides - Dtermination de la rsistance la propagationrapide de la fissure (RCP) - Essai grandeur nature (FST)(ISO 13478:2007)Rohre aus Thermoplasten fr den Transport von Fluiden -Bestimmung des Widerstandes gegenber schnellerRissfortpflanzung (R
7、CP) - Praxistest (FS-Prfung) (ISO13478:2007)This European Standard was approved by CEN on 30 June 2007.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. U
8、p-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN Management Centre or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationund
9、er the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hu
10、ngary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre:
11、rue de Stassart, 36 B-1050 Brussels 2007 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN ISO 13478:2007: EForeword This document (EN ISO 13478:2007) has been prepared by Technical Committee ISO/TC 138 “Plastics pipes, fittings and va
12、lves for the transport of fluids“ in collaboration with Technical Committee CEN/TC 155 “Plastics piping systems and ducting systems” the secretariat of which is held by NEN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endo
13、rsement, at the latest by February 2008, and conflicting national standards shall be withdrawn at the latest by February 2008. This document supersedes EN ISO 13478:1997. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to i
14、mplement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerl
15、and and the United Kingdom. Endorsement notice The text of ISO 13478:2007 has been approved by CEN as a EN ISO 13478:2007 without any modification. BS EN ISO 13478:2007Reference numberISO 13478:2007(E)INTERNATIONAL STANDARD ISO13478Second edition2007-08-15Thermoplastics pipes for the conveyance of f
16、luids Determination of resistance to rapid crack propagation (RCP) Full-scale test (FST) Tubes en matires thermoplastiques pour le transport des fluides Dtermination de la rsistance la propagation rapide de la fissure (RCP) Essai grandeur nature (FST) BS EN ISO 13478:2007ii iiiContents Page Introduc
17、tion v 1 Scope . 1 2 Normative references . 1 3 Terms and definitions. 1 4 Symbols . 2 5 Principle. 2 6 Test parameters 3 7 Materials 3 8 Apparatus 3 9 Test-pipe preparation . 7 10 Conditioning and backfill. 7 11 Test procedure 8 12 Validity of results 8 13 Test report . 9 Annex A (normative) Determ
18、ination of critical pressure (or hoop stress). 10 Annex B (normative) Determination of critical temperature 13 Bibliography . 14 BS EN ISO 13478:2007iv Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The wo
19、rk 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 organizations, governmental and non-governm
20、ental, 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 given in the ISO/IEC Directives, Part 2. The
21、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 least 75 % of the member bodies casting a vote.
22、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 13478 was prepared by Technical Committee ISO/TC 138, Plastics pipes, fittings and valves for the
23、 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 second edition cancels and replaces the first edition (ISO 13478:1997), which has been technically revised. BS EN ISO 13478
24、:2007vIntroduction Test methods that measure the resistance of internally pressurized plastics pipes to rapid fracture propagation (RCP) have been standardized: ISO 134771and this International Standard. The S4 method specified in ISO 13477utilizes short lengths of pipe to determine a critical RCP p
25、ressure or temperature for the pipe. Longer pipes up to 20 m in length are the basis of this full-scale test (FST) method for measurement of these critical parameters. On the one hand, the S4 method uses internal baffles to prevent rapid decompression of the internal test pressure, thus ensuring tha
26、t the high-speed crack tip is exposed to the full pipe pressure throughout the test. The FST, on the other hand, has no baffles installed and is more related to field service. The crack tip is subjected to a reducing pressure by decompression effects as the crack propagates. This arrangement reflect
27、s the RCP mode of failure of long pipelines and is assumed to be the reference test method. The critical RCP values derived from each test are different but can be correlated experimentally. A mathematical equation for correlation has been developed for polyethylene (PE) pipes (see ISO 13477). BS EN
28、 ISO 13478:2007blank1Thermoplastics pipes for the conveyance of fluids Determination of resistance to rapid crack propagation (RCP) Full-scale test (FST) 1 Scope This International Standard specifies a full-scale test (FST) method for determining the arrest or propagation of a crack initiated in a t
29、hermoplastics pipe at a specified temperature and internal pressure. The method is also suitable for the determination of defined critical pressure, critical stress and critical temperature parameters. It is applicable to the assessment of the performance of thermoplastics pipes intended for the sup
30、ply of gases or liquids. In the latter case, air could also be present in the pipe. 2 Normative references The following 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 th
31、e referenced document (including any amendments) applies. ISO 1167-1, Thermoplastics pipes, fittings and assemblies for the conveyance of fluids Determination of the resistance to internal pressure Part 1: General method ISO 3126, Plastics piping systems Plastics components Determination of dimensio
32、ns ISO 11922-1, Thermoplastics pipes for the conveyance of fluids Dimensions and tolerances Part 1: Metric series 3 Terms and definitions For the purposes of this International Standard, the terms and definitions given in ISO 11922-1 and the following apply. 3.1 critical pressure pchighest crack-arr
33、est pressure below the lowest crack-propagation pressure 3.2 critical hoop stress chighest crack-arrest hoop stress below the lowest crack-propagation hoop stress 3.3 critical temperature Tclowest crack-arrest temperature above the highest crack-propagation temperature BS EN ISO 13478:20072 3.4 crac
34、k arrest event characterized by the length of the longest crack that is less than or equal to 90 % of the length of the test pipe 3.5 rapid crack propagation RCP event characterized by the length of the longest crack that is greater than 90 % of the length of the test pipe 4 Symbols p test pressure,
35、 in bar 1)pccritical pressure, in bar1)ccritical hoop stress, in megapascals (MPa) Tccritical temperature, in degrees Celsius (C) demmean outside diameter of test pipe, in millimetres D average of the mean outside diameters, dem, of the pipe sections, in millimetres etmean wall thickness of the test
36、 pipe along the (main) crack, in millimetres. 5 Principle A thermoplastics pipe, maintained at a specified temperature and containing a fluid at a specified test pressure, is subjected to an impact designed to initiate a crack. The crack can then arrest within a short distance or continue to propaga
37、te at high speed along the pipe. The test temperature and test pressure are as defined in the referring standard and are related to the intended operating conditions. The pressurizing fluid is identical to that used in the intended application, or else is a substitute fluid, e.g. air or nitrogen, wh
38、ich gives equivalent results. The test simulates the performance of a buried pipe in service under conditions which do not retard the rate of decompression of the pressurizing fluid through any fracture. The pipe is subsequently examined to determine whether arrest or propagation of the crack has oc
39、curred. From a series of such tests at different pressures but at a constant temperature, a critical pressure or critical stress for crack propagation can be determined (see Annex A). Similarly, by testing at a series of temperatures while maintaining a constant pressure or hoop stress, the critical
40、 temperature for RCP can be determined (see Annex B). 1) 1 bar = 0,1 MPa = 105Pa; 1 MPa = 1 N/mm2. BS EN ISO 13478:200736 Test parameters It is assumed that the following parameters will be set by the referring product standard: a) the diameter(s) and series of the pipe(s) to be tested; b) the press
41、urizing fluid (7.4), e.g. gas, water, water plus air or nitrogen; c) the test pressure(s); d) the test temperature(s). 7 Materials 7.1 Methylated spirits or ethanol, for use as a cooling fluid (see 8.4.3). 7.2 Solid carbon dioxide, for use as a cooling agent (see 8.4.3). 7.3 Washed gravel, with a si
42、ze range of 20 mm to 40 mm diameter (see Clause 10). 7.4 Pressurizing fluid, which shall be as specified in the referring standard. NOTE 1 It is satisfactory to use nitrogen or air as the pressurizing fluid instead of natural gas, as the measured pressure for rapid crack propagation (RCP) will be on
43、ly slightly less than that obtained with natural gas. The decompression speed (velocity of sound) at 0 C of nitrogen and air is 337 m/s and 334 m/s, respectively, compared with approximately 430 m/s for natural gas. NOTE 2 In water-pipeline systems, which contain water only, the phenomenon of crack
44、propagation is unlikely to occur. However, when entrained air bubbles or air pockets are present, it is possible. It is usual to test with between 5 % and 10 % by volume of air in the water to determine the resistance to crack propagation. A test on water pipe using 100 % gas, air or nitrogen is mor
45、e likely to result in RCP and therefore will be expected to give a pessimistic result (also see Reference 2 for RCP testing of pipes filled or partially filled with water). 8 Apparatus 8.1 Temperature-controlled trough, capable of accommodating the overall pipe length normally of 14 m to 20 m (also
46、see Clause 9). The trough shall have means for maintaining the temperature specified by the referring standard to within 1,5 C along the whole test pipe length. The temperature may be controlled by recirculation of water or air around the test pipe (see Figure 1). The temperature shall be monitored
47、at intervals along the test length. If necessary, the water shall contain antifreeze to avoid ice build-up around the test pipe. NOTE Temperature monitoring along the test length at intervals not exceeding 3 m and around the pipe at the 3 oclock and 9 oclock positions has been found to be satisfacto
48、ry. BS EN ISO 13478:20074 Dimensions in millimetres Key lttest length (overall pipe length, l, 14 m to 20 m) 1 steel pipe reservoir 2 gravel 3 required butt-fusion joints 4 initiation ring 5 cooling trough 6 pneumatic piston 7 blade 8 end cap Figure 1 Example of test facility for full-scale rapid cr
49、ack propagation 8.2 Steel-pipe reservoir, connected to the test pipe at one end of the trough. The steel pipe shall have a bore diameter greater than or equal to the test-pipe bore diameter. The pipe reservoir shall have a minimum length of twice that of the test pipe and a minimum volume of three times that of the test pipe. Axial alignment of the reservoir with the test pipe is preferred. 8.3 Pressurization equipment, for pressurizing the test pipe and steel reservoir (8.2) with the test fluid (7.4) to within 2 % of the
