1、BS EN ISO 7233:2016Rubber and plastics hosesand hose assemblies Determination of resistance tovacuum (ISO 7233:2016)BSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06BS EN ISO 7233:2016 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of
2、EN ISO 7233:2016.It supersedes BS EN ISO 7233:2008 which is withdrawn. The UK participation in its preparation was entrusted to TechnicalCommittee PRI/66, Rubber and plastics tubing, hoses and hoseassemblies.A list of organizations represented on this committee can beobtained on request to its secre
3、tary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2016.Published by BSI Standards Limited 2016ISBN 978 0 580 89086 4ICS 23.040.70Compliance with a British Standard cannot co
4、nfer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 31 October 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 7233 October
5、 2016 ICS 23.040.70 Supersedes EN ISO 7233:2008English Version Rubber and plastics hoses and hose assemblies - Determination of resistance to vacuum (ISO 7233:2016) Tuyaux et flexibles en caoutchouc et en plastique - Dtermination de la rsistance laspiration (ISO 7233:2016) This European Standard was
6、 approved by CEN on 24 October 2016. 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-date lists and bibliographical references concerning such na
7、tional 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 translation under the responsibility of a CEN member into its own lan
8、guage 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, Former Yugoslav Republic of Macedonia, France, Germany, Greec
9、e, 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 COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG C
10、EN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2016 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 7233:2016 EBS EN ISO 7233:2016EN ISO 7233:2016 (E) 3 European foreword This document (EN ISO 7233:2016) has be
11、en prepared by Technical Committee ISO/TC 45 “Rubber and rubber products“ in collaboration with Technical Committee CEN/TC 218 “Rubber and plastics hoses and hose assemblies” the secretariat of which is held by BSI. This European Standard shall be given the status of a national standard, either by p
12、ublication of an identical text or by endorsement, at the latest by April 2017, and conflicting national standards shall be withdrawn at the latest by April 2017. 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
13、shall not be held responsible for identifying any or all such patent rights. This document supersedes EN ISO 7233:2008. According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium,
14、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, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland
15、, Turkey and the United Kingdom. Endorsement notice The text of ISO 7233:2016 has been approved by CEN as EN ISO 7233:2016 without any modification. BS EN ISO 7233:2016ISO 7233:2016(E)Foreword ivIntroduction v1 Scope . 12 Normative references 13 Terms and definitions . 14 Principle 15 Apparatus . 16
16、 Test pieces . 27 Conditioning of test pieces . 28 Test pressure 29 Procedure (method A) 210 Procedure (method B) 211 Procedure (method C) 212 Test report . 4Bibliography 6 ISO 2016 All rights reserved iiiContents PageBS EN ISO 7233:2016ISO 7233:2016(E)ForewordISO (the International Organization for
17、 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 committee has been established has the
18、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 electrotechnical standardization.The procedu
19、res 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 drafted in accordance with the editorial
20、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 rights. Details of any patent rights ide
21、ntified 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 constitute an endorsement.For an explanation
22、 on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following URL: www.iso.org/iso/foreword.html.The committee responsible
23、 for this document is ISO/TC 45, Rubber and rubber products, Subcommittee SC 1, Rubber and plastics hoses and hose assemblies.This fourth edition cancels and replaces the third edition (ISO 7233:2006), which has been technically revised with the following changes: Clause 11 has been re-written to cl
24、arify further on the minor axis measurement (D2and D3) as shown in the new Figure 2; as well as addition of a paragraph for examining interior and exterior of the hose; Clause 12 f) has been re-written to include the observation that needs to be made for method C.iv ISO 2016 All rights reservedBS EN
25、 ISO 7233:2016ISO 7233:2016(E)IntroductionVacuum testing is applied to hoses to determine whether they will withstand the differential pressure encountered in service resulting from reduced pressure within the hose. ISO 2016 All rights reserved vBS EN ISO 7233:2016BS EN ISO 7233:2016Rubber and plast
26、ics hoses and hose assemblies Determination of resistance to vacuum1 ScopeThis document specifies three methods for determining the resistance to vacuum of hoses and hose assemblies manufactured from plastic or rubber. Applicable dimensions of hoses for each method are as follows: method A for hoses
27、 of nominal bore up to and including 80 mm; method B for hoses of nominal bore greater than 80 mm; method C for hoses of all dimensions.Methods A and B can also be used to check the adhesion of the lining to the reinforcement (delamination) in a length of hard-wall hose or hose assembly.2 Normative
28、referencesThe following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendmen
29、ts) applies.ISO 4671:2007, Rubber and plastics hoses and hose assemblies Methods of measurement of the dimensions of hoses and the lengths of hose assembliesISO 23529, Rubber General procedures for preparing and conditioning test pieces for physical test methods3 Terms and definitionsFor the purpose
30、s of this document, the terms and definitions given in ISO 8330 apply. ISO and IEC maintain terminological databases for use in standardization at the following addresses: IEC Electropedia: available at http:/www.electropedia.org/ ISO Online browsing platform: available at http:/www.iso.org/obp4 Pri
31、ncipleThe test methodology for determining the resistance to vacuum of plastic and rubber hoses and hose assemblies consists of reducing the internal pressure in a length of hose by means of a vacuum pump and gauge, while examining the hose for any signs of deformation or delamination of reinforceme
32、nt or lining.5 Apparatus5.1 Vacuum pump, provided with a gauge and capable of reducing the internal pressure in the hose within 60 s to the pressure specified in the product standard for the hose under test and maintaining it at that pressure for a minimum of 10 min.INTERNATIONAL STANDARD ISO 7233:2
33、016(E) ISO 2016 All rights reserved 1BS EN ISO 7233:2016ISO 7233:2016(E)5.2 Smooth, solid ball (for method A), with a diameter equal to 0,9 times the bore of the hose under test, rounded down to the nearest whole millimetre.5.3 Two transparent airtight plates (for method B), for sealing each end of
34、the hose. One of the plates shall permit attachment of the vacuum pump to the hose, while allowing internal visual inspection of the hose during the test.6 Test piecesIf the complete hose or hose assembly is more than 1 m long, each test piece shall consist of a minimum length of hose, clear of the
35、end fittings, of 1 m. If the complete hose or hose assembly is less than 1 m long, the complete length shall be used.7 Conditioning of test piecesNo tests shall be carried out within 24 h of manufacture. Test pieces shall be conditioned at the appropriate temperature in accordance with ISO 23529 for
36、 at least 3 h before testing.This 3 h period may form part of the minimum period of 24 h between manufacture and testing.8 Test pressureThe internal pressure to which the hose is subjected to for the duration of the test shall be that stated in the product standard for the hose under test as being t
37、he minimum internal pressure which the hose is required to withstand.9 Procedure (method A)Lay out the hose as straight as possible on a flat surface and blank off one end to form an airtight seal. Insert into the hose a smooth, solid ball (5.2) and then connect the open end of the hose to a vacuum
38、pump and gauge. Reduce the pressure in the hose within 60 s to the required test pressure and maintain this pressure for the required period, which shall not be less than 10 min.While the test pressure is being maintained, examine the hose externally for any signs of indentation or collapse and then
39、 tilt the hose to permit the solid ball to traverse the full length of the hose to check for any obstructions caused by internal deformation or delamination.10 Procedure (method B)Lay out the hose as straight as possible on a flat surface and fit transparent airtight plates (5.3) to both ends of the
40、 hose, one of which shall then be connected to a vacuum pump and gauge. Reduce the pressure in the hose within 60 s to the required test pressure and maintain this pressure for the required period, which shall not be less than 10 min.While the test pressure is being maintained, examine the interior
41、of the hose through one of the transparent plates by means of illumination supplied through the transparent plate at the other end of the hose for signs of delamination or blistering of the lining. Also examine the exterior of the hose for signs of indentation or collapse.11 Procedure (method C)Lay
42、out the hose as straight as possible on a flat surface, blank off one end to form an airtight seal, and connect the other end to a vacuum pump and gauge.2 ISO 2016 All rights reservedBS EN ISO 7233:2016ISO 7233:2016(E)Before reducing the pressure in the hose, mark two lines (lines A and B), equidist
43、ant from the centre and 500 mm apart, round the hose (see Figure 1). Then, mark a third line (line C) round the hose at a point between lines A and B. Measure the average outside diameter of the hose round line C in accordance with the method specified in ISO 4671:2007, 5.2.Dimensions in millimetres
44、KeyA, B lines marked on test piece for measurement of change in lengthC line marked on test piece for measurement of change in outside diameterFigure 1 Marking measurement lines on test pieceKey1 minor axis (D2, D3)Figure 2 Minor axis of a deformed test pieceReduce the pressure in the hose to the re
45、quired test pressure and maintain this pressure for the required period, which shall not be less than 10 min. After 10 min or the required test period (whichever is greater) and before releasing the pressure, measure the distance between lines A and B, as well as the minor axis, D2, (see Figure 2) r
46、ound line C, as before.Release the pressure and, after 10 min, measure, for a third time, the distance between lines A and B and the minor axis, D3, round line C.After releasing the pressure, examine the interior of the hose for signs of delamination or blistering of the lining. Also examine the ext
47、erior of the hose for signs of indentation or collapse. ISO 2016 All rights reserved 3BS EN ISO 7233:2016ISO 7233:2016(E)The percentage change in the length of the hose, L, before and after releasing the pressure is given by Formula (1) and Formula (2):LLLLt=211100 (1)LLLLp=311100 (2)whereLtis the t
48、emporary length change (before releasing the pressure);Lpis the permanent length change (after releasing the pressure);L1is the distance between lines A and B before reducing the pressure, in millimetres;L2is the distance between lines A and B before releasing the pressure, in millimetres;L3is the d
49、istance between lines A and B after releasing the pressure, in millimetres.The percentage change in the outside diameter of the hose, D, before and after releasing the pressure is given by Formula (3) and Formula (4):DDDDt=211100 (3)DDDDp=311100 (4)whereDtis the temporary outside diameter change (before releasing the pressure);Dpis the permanent outside diameter change (after releasing the pressure);D1is the average outside diameter of the hose before reducing the pressure, in millimetr
