1、BSI Standards PublicationBS EN ISO 9967:2016Thermoplastics pipes Determination of creep ratioBS EN ISO 9967:2016 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN ISO 9967:2016.It supersedes BS EN ISO 9967:2007 which is withdrawn.The UK participation in its prepar
2、ation was entrusted to TechnicalCommittee PRI/88/4, Test Methods - Plastic Piping.A list of organizations represented 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 cor
3、rectapplication. The British Standards Institution 2016.Published by BSI Standards Limited 2016ISBN 978 0 580 81162 3ICS 23.040.20Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strateg
4、y Committee on 31 January 2016.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 9967 January 2016 ICS 23.040.20 Supersedes EN ISO 9967:2007English Version Thermoplastics pipes - Determination of creep ratio (ISO 9967:2
5、016) Tubes en matires thermoplastiques - Dtermination du taux de fluage (ISO 9967:2016) Thermoplastische Rohre - Bestimmung des Verformungsverhaltens (ISO 9967:2016) This European Standard was approved by CEN on 7 November 2015. CEN members are bound to comply with the CEN/CENELEC Internal Regulatio
6、ns which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-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. T
7、his European Standard exists in three official versions (English, French, German). A version in any other language made by translation 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 me
8、mbers are the national standards bodies of 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, Poland, Port
9、ugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2016 CEN All rights of exploitation in any f
10、orm and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 9967:2016 EBS EN ISO 9967:2016EN ISO 9967:2016 (E) 3 European foreword This document (EN ISO 9967:2016) has been prepared by Technical Committee ISO/TC 138 “Plastics pipes, fittings and valves for the transport of flui
11、ds“ 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 endorsement, at the latest by July
12、 2016, and conflicting national standards shall be withdrawn at the latest by July 2016. Attention is drawn to the possibility that some of the elements of 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 right
13、s. This document supersedes EN ISO 9967:2007. This document has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association. According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound
14、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, Poland, Portugal,
15、Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 9967:2016 has been approved by CEN as EN ISO 9967:2016 without any modification. BS EN ISO 9967:2016ISO 9967:2016(E)Foreword ivIntroduction v1 Scope . 12 Normative references 13
16、 Symbols 14 Principle 25 Apparatus . 26 Test pieces . 36.1 Marking and number of test pieces . 36.2 Length of test pieces . 36.3 Inside diameter of test piece(s) 46.4 Age of test pieces . 47 Conditioning 58 Test procedure 59 Determination of the creep ratio . 610 Test report . 9Annex A (informative)
17、 Creep in thermoplastics material .10Bibliography .12 ISO 2016 All rights reserved iiiContents PageBS EN ISO 9967:2016ISO 9967:2016(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing Int
18、ernational 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-governmental, in liaison w
19、ith ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directive
20、s, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted 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
21、 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. 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 declaration
22、s received (see www.iso.org/patents).Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement.For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about IS
23、Os adherence to the WTO principles in the Technical Barriers to Trade (TBT) see the following URL: Foreword - Supplementary informationThe committee responsible for this document is ISO/TC 138, Plastics pipes, fittings and valves for the transport of fluids, Subcommittee SC 5, General properties of
24、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 9967:2007), which has been technically revised.iv ISO 2016 All rights reservedBS EN ISO 9967:2016ISO 9967:2016(E)IntroductionEx
25、perience shows that when a pipe is installed in the soil in accordance with an appropriate code of practice an increase in deflection may be observed. Depending on the soil and installation conditions this period will vary but normally not exceed two years.Therefore, the two-year creep ratio as dete
26、rmined in accordance with this International Standard is intended for use when long-term static calculations are carried out.The theory of creep in thermoplastics materials is briefly explained in Annex A.For experiments, the test can be carried out based on other ages of the test pieces, other test
27、 temperatures and/or other test durations. ISO 2016 All rights reserved vBS EN ISO 9967:2016BS EN ISO 9967:2016Thermoplastics pipes Determination of creep ratio1 ScopeThis International Standard specifies a method for determining the creep ratio of thermoplastics pipes having a circular cross-sectio
28、n.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amen
29、dments) applies.ISO 3126, Plastics piping systems Plastics components Determination of dimensions3 SymbolsUnitdnnominal diameter of pipe mmdiinside diameter of test piece of pipe mmF loading force kNF0pre-load force Np pitch mmL length of test piece mmy0measured initial deflection mmYtcalculated def
30、lection at time t mmY2extrapolated two-year deflection mm vertical deflection used to determine the loading force mmB theoretical deflection, at t = 1 h mmM gradient coefficientN number of points on the deflection curve used for the linear regressionR correlation coefficientt time hx log(t)y measure
31、d total deflection mm creep ratioINTERNATIONAL STANDARD ISO 9967:2016(E) ISO 2016 All rights reserved 1BS EN ISO 9967:2016ISO 9967:2016(E)S stiffness kN/m2E modulus of elasticity of the material kN/m2I moment of inertia m3D mean diameter of the test ring m4 PrincipleA cut length of pipe is placed be
32、tween two parallel flat horizontal plates and a constant compressive force is applied for 1 008 h (42 days).The deflection of the pipe is recorded at specified intervals so as to prepare a plot of pipe deflection against time. The linearity of the data are analysed and the creep ratio is calculated
33、as the ratio between the two years extrapolated deflection value and the measured 6 min (0,1 h) deflection.NOTE It is assumed that the test temperature, as appropriate (see 8.1), is set by the referring standard.5 Apparatus5.1 Compressive loading machine, capable of applying via plates (5.2) and mai
34、ntaining to with a precision of 1 % both the applicable pre-load force, F0(see 8.4), and the necessary loading force, F (see 8.5), on the pipe.The force may be applied either directly or indirectly, e.g. by use of a lever arm arrangement.5.2 Two plates, through which the compressive force can be app
35、lied to the test piece. The plates shall be flat, smooth and clean and shall not deform during the test to an extent that would affect the results.The length of each plate shall be at least equal to the length of the test piece. The width of each plate shall be not less than the maximum width of the
36、 contact surface with the test piece while under load plus 25 mm.5.3 Dimensional measuring devices, capable of determining: individual values for the length of a test piece (see 6.2) to with an accuracy of 1 mm; the inside diameter of a test piece to with an accuracy of 0,1 mm or 0,2 % di, whichever
37、 is the greater; the change in inside diameter of a test piece in the direction of loading with an accuracy of 0,1 mm or 0,1 % of the deflection, whichever is the greater.The change in inside diameter may be measured inside the pipe or be determined from the movement of the upper plate. In case of d
38、ispute the inside diameter shall be used as reference.An example of a device for measuring the inside diameter of corrugated pipes is shown in Figure 1.Figure 1 Example of device for measuring the inside diameter of a corrugated pipe2 ISO 2016 All rights reservedBS EN ISO 9967:2016ISO 9967:2016(E)5.
39、4 Timer, capable of determining the first 6 min with an accuracy to within 1 s and the remaining times to within 0,1 % (see 8.5 and 8.6).6 Test pieces6.1 Marking and number of test piecesThe pipe of which the creep ratio is to be determined shall be marked on its outside with a line along one genera
40、trix for its full length. Three test pieces, A, B and C respectively, shall be taken from this marked pipe such that the ends of the test pieces are perpendicular to the pipe axis and their lengths conform to 6.2.6.2 Length of test pieces6.2.1 The length of each test piece shall be determined by cal
41、culating the arithmetic average of three to six measurements of length equally spaced around the perimeter of the pipe as given in Table 1. The length of each test piece shall conform to 6.2.2, 6.2.3, 6.2.4 or 6.2.5, as applicable.Each of the three to six length measurements shall be determined to w
42、ithin 1 mm.For each individual test piece, the smallest of the three to six measurements shall not be less than 0,9 times the largest length measurement.Table 1 Number of length measurementsNominal diameter, dn, of pipeNumber of length measurementsmmdn 200 3200 dn 500 4dn 500 66.2.2 For pipes that h
43、ave a nominal diameter, dn, less than or equal to 1 500 mm, the average length of the test pieces shall be (300 10) mm.6.2.3 For pipes that have a nominal diameter, dn, larger than 1 500 mm, the average length of the test pieces in millimetres shall be at least 0,2 dn.6.2.4 Structured wall pipes wit
44、h perpendicular ribs, corrugations or other regular structures shall be cut such that each test piece contains a whole number of ribs, corrugations or other structures. The cuts shall be made at the mid-point between the ribs, corrugations or other structures. The length of the test pieces shall be
45、the minimum whole number of ribs, corrugations or other structures resulting in a length of 290 mm or greater, or 0,2 dnor greater for pipes larger than 1 500 mm. See Figure 2. ISO 2016 All rights reserved 3BS EN ISO 9967:2016ISO 9967:2016(E)Keyp pitchL length of test pieceFigure 2 Test piece cut ou
46、t of a perpendicularly ribbed pipe6.2.5 Structured-wall pipes with helical ribs, corrugations or other regular structures shall be cut square such that the length of the test pieces is equal to the inside diameter 20 mm but not less than 290 mm or greater than 1 000 mm.6.3 Inside diameter of test pi
47、ece(s)The inside diameters, diA, diBand diC, of the respective test pieces, A, B and C (see 6.1), shall be determined either asa) the arithmetic average of four or more measurements in accordance with ISO 3126 of one cross-section at mid-length, where each measurement shall be determined to with an
48、accuracy of 0,1 mm or 0,2 % di, whichever is the greater, orb) measured at mid-length of cross-section by means of a -tape in accordance with ISO 3126.The calculated or measured average inside diameter for each test piece, A, B and C, shall be recorded as diA, diBand diCrespectively.The average valu
49、e, di, of these three calculated values shall be calculated using Formula (1):ddddiiA iB iC3=+(1)6.4 Age of test piecesAt the start of testing in accordance with Clause 8, the age of the test pieces shall be (21 2) days.4 ISO 2016 All rights reservedBS EN ISO 9967:2016ISO 9967:2016(E)7 ConditioningThe test pieces shall be conditioned in air at the test temperature (see 8.1) for at least 24 h immediately prior to testing in accordance with Clause 8.8 Test procedure8.1 Unless otherwise specified in the referring sta
