1、BRITISH STANDARD BS EN 12434:2000 Incorporating Corrigendum No. 1 Cryogenic vessels Cryogenic flexible hoses The European Standard EN 12434:2000 has the status of a British Standard ICS 23.020.40; 23.040.70 BS EN 12434:2000 This British Standard, having been prepared under the direction of the Engin
2、eering Sector Policy and Strategy Committee, was published under the authority of the Standards Policy and Strategy Committee on 15 October 2000 BSI 4 October 2002 ISBN 0 580 36420 8 National foreword This British Standard is the official English language version of EN 12434:2000, including Corrigen
3、dum February 2001. The UK participation in its preparation was entrusted to Technical Committee PSE/18, Cryogenic vessels, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which
4、implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publicatio
5、n does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/Eu
6、ropean committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN title page,
7、pages 2 to 18, an inside back cover and a back cover. The BSI copyright date displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date Comments 14115 Corrigendum No. 1 4 October 2002 Correction to the technical committee details cited i
8、n the EN forewordEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 12434 August 2000 ICS 23.020.40; 23.040.70 Incorporating corrigendum February 2001 English version Cryogenic vessels - Cryogenic flexible hoses Rcipients cryogniques - Tuyaux flexibles cryogniques Kryo-Behlter - Kryoschlauchleitun
9、gen This European Standard was approved by CEN on 7 July 2000. 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 ref
10、erences concerning such national standards may be obtained on application to the Central Secretariat 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
11、into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal
12、, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Central Secretariat: rue de Stassart, 36 B-1050 Brussels 2000 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN n
13、ational Members. Ref. No. EN 12434:2000 EPage 2 EN 12434:2000 Contents Page Foreword3 1 Scope 4 2 Normative references 4 3 Terms and definitions4 4 General requirements5 4.1 Design and construction.5 4.2 Materials .6 4.3 Cleanliness .6 4.4 Mechanical properties.6 4.4.1 Burst pressure .6 4.4.2 Pressu
14、re cycles6 4.4.3 Bending.6 4.4.4 Resistance to abuse 6 4.4.5 Low temperature resistance .6 4.4.6 Leak tightness6 4.4.7 Electrical properties 7 5 Hose sample tests .7 5.1 General7 5.2 Non-destructive tests and inspection8 5.2.1 Identification of materials .8 5.2.2 Dimensional check 8 5.2.3 Cleanlines
15、s check8 5.2.4 Pressure test 8 5.2.5 Leak tests .8 5.2.6 Crushing test9 5.3 Destructive tests9 5.3.1 Hydraulic pressure cycling.9 5.3.2 Rolling bend cycling test 9 5.3.3 Hydraulic bursting test9 5.3.4 Examination of sectional cut 10 6 Production testing .10 6.1 Pressure test 10 6.2 Leak test .10 7 M
16、arking .10 8 Cleaning10 9 Periodic examination.10 10 Test certificate11 Annex A (normative) Typical hose assembly.12 Annex B (normative) Rolling bend cycling test for metallic hose assemblies and hose assemblies made of materials with a record of satisfactory use in cryogenic service 13 Annex C (nor
17、mative) Rolling bend cycling test for hose assemblies constructed from materials or composites not commonly used in cryogenic service15 Annex D (informative) Guidelines for periodic examination of transfilling hoses .17 Annex ZA (informative) Clauses of this European Standard addressing essential re
18、quirements or other provisions of EU directives. .18Page 3 EN 12434:2000 Foreword This European Standard has been prepared by Technical Committee CEN/TC 268 “Cryogenic vessels”, the secretariat of which is held by BSI. This European Standard shall be given the status of a national standard, either b
19、y publication of an identical text or by endorsement, at the latest by February 2001, and conflicting national standards shall be withdrawn at the latest by February 2001. This European Standard has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Ass
20、ociation, and supports essential requirements of EU Directive(s). For relationship with EU Directive(s), see informative Annex ZA, which is an integral part of this standard. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound
21、to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom.Page 4 EN 12434:2000 1 Scope This standard gives design, constructio
22、n, type and production testing, and marking requirements for non insulated cryogenic flexible hose used for the transfer of cryogenic fluids within the following range of operating conditions : working temperature: from - 270 C to + 65 C ; maximum nominal pressure: 80 bar ; nominal size (DN): from 1
23、0 to 100. End fittings for mounting of any couplings are within the scope of this standard, but the couplings are subject to other standards. It is intended that the hose be designed and tested to satisfy the generally accepted nominal pressure e.g. PN 40. Hoses may then be selected with a PN equal
24、to or greater than the maximum allowable pressure (PS) of the equipment to which it is to be used. 2 Normative references This European Standard incorporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text
25、and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies
26、(including amendments). EN 1252-1, Cryogenic vessels - Materials - Part 1 : Toughness requirements for temperatures below - 80 C EN 1333, Pipework components - Definition and selection of PN EN 1797-1, Cryogenic vessels - Gas/materials compatibility - Oxygen compatibility EN 12300, Cryogenic vessels
27、 - Cleanliness for cryogenic service EN ISO 6708, Pipework components - Definition and selection of DN (nominal size) (ISO 6708:1995) ISO 7369:1995, Pipework - Flexible metallic hoses - Vocabulary of general terms 3 Terms and definitions For the purposes of this Standard, in addition to those given
28、in ISO 7369:1995, the following terms and definitions apply : 3.1 hose A flexible leak tight inner tube either corrugated metal, elastomer or plastic. 3.2 braid A layer, or layers, of cylindrically woven wires covering the hose and attached to the flexible hose assembly end fittings, serving the fun
29、ction of restraining the flexible hose against elongation. 3.3 protection coil or cover An outer coil or cover fitted to protect the main hose and braid against damage and abrasion.Page 5 EN 12434:2000 3.4 end fitting A fitting (of material compatible with material and product transferred) attached
30、to each end of the hose and braid (when fitted). 3.5 hose assembly A hose with end fittings attached, complete with braid and/or other covering, ready for service. 3.6 nominal size (DN) As defined in EN ISO 6708. 3.7 nominal pressure (PN) As defined in EN 1333. NOTE 1 PN PS (as defined in PED) NOTE
31、2 See also the last sentence of the scope. 3.8 working temperature range The highest and lowest temperature to which the hose assembly is to be subjected. 3.9 cyclic life Minimum number of complete cycles which, at the test conditions, the hose assembly is designed to withstand without failure. 4 Ge
32、neral requirements 4.1 Design and construction The nominal pressure used during tests (see clause 5) shall be greater than or equal to the nominal pressure (PN) specified. In addition, the nominal pressure (PN) shall not be less than the maximum allowable pressure (PS) of the equipment to which it i
33、s to be used. A hose is typically made from corrugated metal, from strip steel. The corrugation may be parallel or helicoil. The nominal pressure stamped on the hose assembly shall be greater than or equal to the maximum pressure in service. If elastomers or composites are used, additional requireme
34、nts shall be applied in accordance with 5.3.2.2. A braid is commonly fitted over the inner tube. This, generally, consists of woven wire in one or two layers, in stainless steel or a high strength copper alloy. It may have a cover, which shall be compatible with the surroundings and, normally, with
35、the conveyed fluid. The design shall ensure that pressurisation, or corrosion, between the inner tube and the outer braid or sheath is prevented. End fittings shall be designed as a rigid seal to the ends of a hose to ensure : a tight fixing to the hose ; a strong joint between the braid and hose to
36、 stabilise the hose against elongation at nominal pressure. An area for marking shall be provided on one of the end fittings. A typical cryogenic hose assembly is shown in annex A.Page 6 EN 12434:2000 4.2 Materials All materials shall be compatible with the fluid conveyed. End connections and coupli
37、ngs shall be made of materials compatible with the materials of the flexible hose assembly. A material is said to be compatible when it does not lead to any violent reaction (ignition,etc.) or any slow reaction (ageing) with the conveyed gases, and has a little permeability. The materials used in a
38、cryogenic hose assembly service shall : maintain sufficient ductility at the lowest working temperature (as specified in EN 1252-1) ; be oxygen compatible, if specified for oxygen or nitrous oxide service (as specified EN 1797-1) ; contain less than 70 % copper, in the alloy as well as the soldering
39、 materials, if it is specified for mixtures containing acetylene. 4.3 Cleanliness Hose assemblies specified for all cryogenic fluids shall be cleaned in accordance with EN 12300. NOTE Measures should be taken during manufacture to remove or avoid hydrocarbons, moistures, particles or other contamina
40、tions inside the hose assembly. 4.4 Mechanical properties 4.4.1 Burst pressure The burst pressure shall be at least three times the nominal pressure within the temperature range of 270 C to + 65 C. Failure shall occur only in the body of the hose and braid and not in their connections. 4.4.2 Pressur
41、e cycles Hose assemblies shall have a minimum cyclic life 10 000 cycles when pressurised from 1 bar to nominal pressure repeatedly in accordance with 5.3.1. 4.4.3 Bending Hose assemblies shall have a minimum cyclic life of 50 000 cycles when repeatedly rolled at nominal pressure in accordance with 5
42、.3.2. 4.4.4 Resistance to abuse Hose assemblies should have a sufficient resistance to detoriation of the braid when they are dragged on the ground. For additional protection of the braid, e.g. a coil can be used. Hose assemblies shall withstand to a crushing test, simulating a person stepping on th
43、e hose assembly, in accordance with 5.2.6. 4.4.5 Low temperature resistance All components of the hose assemblies which become cold during operation shall retain their toughness at the lowest design temperature. 4.4.6 Leak tightness Hose assemblies shall be leak tight in accordance with 6.2.Page 7 E
44、N 12434:2000 4.4.7 Electrical properties Hose assemblies specified for flammable products shall be electrically conducting from one end to the other (electric resistance less than 0,5 ). 5 Hose sample tests 5.1 General The hose sample test procedures shall include : a) Inspection and non-destructive
45、 tests : 1) inspection: dimensions, cleanliness, material identification and marking ; 2) tests: pressure test, leak and crushing tests. b) Destructive tests : pressure cycling, bursting test, rolling bend cycling and examination of sectional cut. The tests shall be recorded in a written report whic
46、h shall be retained. Four hoses ( A, B, C and D ) are necessary to perform hose sample tests for each hose sample of hose assembly. The tests and order of tests (1, 2, 3) are summarised in Table 1. Table 1 Testing scope and sequence Tests Hose assembly ABCD 1 Non destructive tests a) Identification
47、of materials b) Dimensional check c) Cleanliness check d) Pressure test 1111 e) Leak test 4 3 f) Crushing test 2 2 - 2 2 Destructive tests a) Hydraulic pressure cycling 3 - - - b) Rolling bend cycling - 3 2 - c) Hydraulic bursting 4 5 - 3 d) Examination of a sectional cut - - 4 -Page 8 EN 12434:2000
48、 When a hose assembly with a given DN oand a given nominal pressure P ohas been successfully sample tested, any hose assembly of the same type, having : a nominal pressure P o a nominal diameter 1,5 DN can be considered as approved. A hose assembly is said to be of the same type when the design and
49、its characteristics are similar to the tested hose: similarly is defined as having the same materials, welding method, type of corrugation (shape, method of manufacturing), method of joining (hose and end fitting), braid (type of braiding, i.e. calculated - according to diameters - to obtain the same maximum tensile stress in each wire, same materials, same welding method, .). Hose sample tests shall be carried out on hose assembly of a given length (see annex
