1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN ISO 9080:2012Plastics piping and ductingsystems Determinationof the long-term hydrostaticstrength of thermoplasticsmaterials in pipe form byextrapolationBS EN ISO 9080:2012
2、 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN ISO 9080:2012.It supersedes BS EN ISO 9080:2003 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee PRI/88/4, Test Methods - Plastic Piping.A list of organizations repres
3、ented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2012. Published by BSI StandardsLimited 2012ISBN 978 0 580 62
4、583 1ICS 23.040.20Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 31 October 2012.Amendments issued since publicationDate Text affectedEUROPEAN STANDARD NORME EURO
5、PENNE EUROPISCHE NORM EN ISO 9080 October 2012 ICS 23.040.20 Supersedes EN ISO 9080:2003English Version Plastics piping and ducting systems - Determination of the long-term hydrostatic strength of thermoplastics materials in pipe form by extrapolation (ISO 9080:2012) Systmes de canalisations et de g
6、aines en matires plastiques - Dtermination de la rsistance hydrostatique long terme des matires thermoplastiques sous forme de tubes par extrapolation (ISO 9080:2012) Kunststoff-Rohrleitungs- und Schutzrohrsysteme - Bestimmung des Zeitstand-Innendruckverhaltens von thermoplastischen Rohrwerkstoffen
7、durch Extrapolation (ISO 9080:2012) This European Standard was approved by CEN on 6 October 2012. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to
8、-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC 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 translat
9、ion under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland,
10、Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION CO
11、MIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2012 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 9080:2012: EBS EN ISO 9080:2012EN ISO 9080:2012 (E) 3 Forewor
12、d This document (EN ISO 9080:2012) has been prepared by Technical Committee ISO/TC 138 “Plastics pipes, fittings and valves for the transport of fluids“ in collaboration Technical Committee CEN/TC 155 “Plastics piping systems and ducting systems” the secretariat of which is held by NEN. This Europea
13、n Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by April 2013, and conflicting national standards shall be withdrawn at the latest by April 2013. Attention is drawn to the possibility that some of the elements o
14、f this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes EN ISO 9080:2003. According to the CEN/CENELEC Internal Regulations, the national standards organisations of the following cou
15、ntries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, P
16、oland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 9080:2012 has been approved by CEN as a EN ISO 9080:2012 without any modification. BS EN ISO 9080:2012ISO 9080:2012(E) ISO 2012 All rights reserved iiiContents
17、PageForeword ivIntroduction v0.1 General . v0.2 Principles . v0.3 Use of the methods vi1 Scope 12 Normative references . 13 Terms and definitions . 14 Acquisition of test data 34.1 Test conditions . 34.2 Distribution of internal pressure levels and time ranges . 35 Procedure 35.1 Data gathering and
18、analysis . 35.2 Extrapolation time factors for polyolefins (semi-crystalline polymers) . 65.3 Extrapolation time factors for glassy, amorphous vinyl chloride based polymers 75.4 Extrapolation time factors for polymers other than those covered in 5.2 and 5.3 76 Example of calculation, software valida
19、tion 77 Test report . 8Annex A (normative) Methods of analysis . 9Annex B (normative) Automatic knee detection 13Annex C (informative) Application of SEM to stress rupture data of a semi-crystalline polymer 14Annex D (informative) Application of SEM to stress rupture data of a vinyl chloride based p
20、olymer 22Annex E (informative) Software for calculation of stress-rupture data according to ISO 9080 28Bibliography .29BS EN ISO 9080:2012ISO 9080:2012(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The w
21、ork 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-govern
22、mental, 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 m
23、ain 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.At
24、tention 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 9080 was prepared by Technical Committee ISO/TC 138, Plastics pipes, fitings and valves for the tran
25、sport 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 9080:2003), which has been technically revised. The following changes
26、 have been made: all references to lifetime have been removed, as this standard only deals with the mathematics for extrapolation and the calculation of long-term strength; a more accurate description of the number and distribution of the observations and of the use of the extrapolation has been inc
27、luded; the observations in the example of Annex C have been modified in order to comply with the specifications of this standard and, consequently, the results of the regression calculations have been updated; a second set of observations has been added in Annex D in order to provide an evaluation a
28、ccording to the 3-parameter model (see Annex C), and according to the 4-parameter model (see Annex D); a second software package has been evaluated and included in Annex E.iv ISO 2012 All rights reservedBS EN ISO 9080:2012ISO 9080:2012(E)Introduction0.1 GeneralThis Standard Extrapolation Method (SEM
29、) is meant to be used to evaluate the long-term hydrostatic strength of a material in pipe form. Product standards have specific requirements for the physical and mechanical properties of the material used for the intended application. It is emphasized that the Standard Extrapolation Method (SEM) de
30、scribed in this document is not intended to be used to disqualify existing procedures for arriving at design stresses or allowable pressures for pipelines made of plastics materials, or to disqualify pipelines made of materials proven by such procedures, for which experience over many years has been
31、 shown to be satisfactory.Software packages have been developed for the SEM analysis as described in Annex A and Annex B. Windows-based programmes are commercially available (see Annex E). Use of these software packages is recommended.0.2 PrinciplesThe suitability of a plastics material for a pressu
32、re pipe is determined by its long-term performance under hydrostatic stress when tested in pipe form, taking into account the envisaged service conditions (e.g. temperature). For design purposes, it is conventional to express this by means of the hydrostatic (hoop) stress which a plastics pipe made
33、of the material under consideration is expected to be able to withstand for 50 years at an ambient temperature of 20 C using water as the internal test medium. The outside test environment can be water or air. This method is not intended to imply service life. In certain cases, it is necessary to de
34、termine the value of the hydrostatic strength at either shorter design times or higher temperatures, or on occasion both. The method given in this International Standard is designed to meet the need for both types of estimate. The result obtained will indicate the lower prediction limit (LPL), which
35、 is the lower confidence limit of the prediction of the value of the stress that can cause failure in the stated time at a stated temperature.This International Standard provides a definitive procedure incorporating an extrapolation method using test data at different temperatures analysed by multip
36、le linear regression analysis. The results permit the determination of material-specific design values in accordance with the procedures described in the relevant product standards.This multiple linear regression analysis is based on the rate processes most accurately described by log10(stress) vers
37、us log10(time) models.In order to assess the predictive value of the model used, it has been considered necessary to make use of the estimated 97,5 % lower prediction limit (LPL). The 97,5 % lower prediction limit is equivalent to the lower 97,5 % confidence limit for the predicted value. This conve
38、ntion is used in the mathematical calculations to be consistent with the literature. This aspect necessitates the use of statistical techniques.The method can provide a systematic basis for the interpolation and extrapolation of stress rupture characteristics at operating conditions different from t
39、he conventional 50 years at 20 C (see 5.1.5).Thermoplastic materials in pipe form such as mineral filled thermoplastic polymer, fibre reinforced thermoplastics, plasticized thermoplastics, blends and alloys may have further considerations with regards to prediction of long term strength which have t
40、o be taken into account in the corresponding product standards.It is essential that the medium used for pressurizing the pipe does not have an adverse effect on the pipe. In general, water is considered to be such a medium.Long consideration was given to deciding which variable should be taken as th
41、e independent variable to calculate the long-term hydrostatic strength. The choice was between time and stress.The basic question the method has to answer can be formulated in two ways, as indicated below:a) What is the maximum stress (or pressure) that a given material in pipe form can withstand at
42、 a given temperature for a defined time? ISO 2012 All rights reserved vBS EN ISO 9080:2012ISO 9080:2012(E)b) What is the predicted time to failure for a material in pipe form at a given stress and temperature?Both questions are relevant.If the test data for the pipe under study does not show any sca
43、tter and if the pipe material can be described perfectly by the chosen empirical model, the regression with either time independence or stress independence will be identical. This is never the case because the circumstances of testing are never ideal nor will the material be 100 % homogeneous. The o
44、bservations will therefore always show scatter. The regressions calculated using the two optional independent variables will not be identical and the difference will increase with increasing scatter.The variable that is assumed to be most affected by the largest variability (scatter) is the time var
45、iable and it has to be considered as a dependent variable (random variable) in order to allow a correct statistical treatment of the data set in accordance with this method. However, for practical reasons, the industry prefers to present stress as a function of time as an independent variable.0.3 Us
46、e of the methodsThe purpose of this extrapolation method is to estimate the following:a) The lower prediction limit1)(at 97,5 % probability level) of the stress which a pipe made of the material under consideration is able to withstand for 50 years at an ambient temperature of 20 C using water or ai
47、r as the test environment. In accordance with ISO 12162, the categorised value of this lower prediction limit is defined as MRS and is used for classification of the material.b) The value of the lower prediction limit (at 97,5 % probability level) of the stress, either at different design times or a
48、t different temperatures, or on occasion both. In accordance with ISO 12162, the categorised value of this lower prediction limit is defined as CRS,tand is used for design purposes.There are several extrapolation models in existence, which have different numbers of terms. This SEM will use only mode
49、ls with two, three or four parameters.Adding more terms could improve the fit but would also increase the uncertainty of the predictions.The SEM describes a procedure for estimating the lower prediction limit (at 97,5 % probability level) whether a knee (which demonstrates the transition between data type A and type B) is found or not (see Annex B).The materials are tested in pipe form for the method to be applicable.The final result of the SEM for a specific material is the lower prediction limit (at 97,5 % probability level) of the hydrostatic streng
