1、 g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58ICS 23.020.40; 83.140.40Cryogenic vessels HosesBRITISH STANDARDBS ISO 21012:2006BS ISO 21012:2006Th
2、is British Standard was published under the authority of the Standards Policy and Strategy Committee on 29 June 2007 BSI 2007ISBN 978 0 580 52917 7Amendments issued since publicationAmd. No. Date Commentscontract. Users are responsible for its correct application.Compliance with a British Standard c
3、annot confer immunity from legal obligations.National forewordThis British Standard was published by BSI. It is the UK implementation of ISO 21012:2006.The UK participation in its preparation was entrusted to Technical Committee PVE/18, Cryogenic vessels.A list of organizations represented on this c
4、ommittee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a Reference numberISO 21012:2006(E)INTERNATIONAL STANDARD ISO21012First edition2006-11-15Cryogenic vessels Hoses Rcipients cryogniques Tuyaux BS ISO 21012:2006ii iiiConte
5、nts Page Foreword iv 1 Scope . 1 2 Normative references . 1 3 Terms and definitions. 1 4 General requirements. 2 4.1 Design and construction 2 4.2 Materials 3 4.3 Cleanliness 3 4.4 Mechanical properties 3 5 Hose sample tests 4 5.1 General. 4 5.2 Non-destructive tests and inspection. 5 5.3 Destructiv
6、e tests. 6 6 Production testing 7 6.1 General. 7 6.2 Pressure test . 7 6.3 Leak test 7 7 Marking 7 8 Cleaning. 8 9 Test certificate. 8 Annex A (informative) Typical hose assembly 9 Annex B (normative) Rolling bend cycling test for metallic hose assemblies and hose assemblies made of materials with a
7、 record of satisfactory use in cryogenic service. 10 Annex C (normative) Rolling bend cycling test for hose assemblies constructed from materials or composites not commonly used in cryogenic service. 12 Bibliography . 14 BS ISO 21012:2006iv Foreword ISO (the International Organization for Standardiz
8、ation) 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 right to be
9、 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. International Standar
10、ds are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The 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 Intern
11、ational Standard requires approval by at least 75 % of the member bodies casting a vote. 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 21012 wa
12、s prepared by Technical Committee ISO/TC 220, Cryogenic vessels. BS ISO 21012:20061Cryogenic vessels Hoses 1 Scope This International Standard gives design, construction, type and production testing, and marking requirements for non-insulated cryogenic flexible hoses used for the transfer of cryogen
13、ic fluids within the following range of operating conditions: working temperature: from 270 C to 65 C; nominal size (DN): from 10 to 100. End fittings for mounting of any couplings are within the scope of this International Standard, but the couplings are subject to other standards. 2 Normative refe
14、rences 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 the referenced document (including any amendments) applies. ISO 7369, Pipework Metal hoses and hose as
15、semblies Vocabulary ISO 10806:2003, Pipework Fittings for corrugated metal hoses ISO 21010, Cryogenic vessels Gas/materials compatibility ISO 21028-1, Cryogenic vessels Toughness requirements for materials at cryogenic temperature Part 1: Temperatures below 80 C ISO 23208, Cryogenic vessels Cleanlin
16、ess for cryogenic service 3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 7369 and the following apply. 3.1 hose flexible leak-tight inner tube of either corrugated metal, elastomer or plastic 3.2 braid layer, or layers, of cylindrically woven wires
17、covering the hose and permanently attached to the flexible hose assembly end fittings, serving the function of restraining the flexible hose against elongation 3.3 protection coil or cover outer coil or cover fitted to protect the main hose and braid against damage and abrasion BS ISO 21012:20062 3.
18、4 end fitting fitting (of material compatible with material and product transferred) attached to each end of the hose and braid (when fitted) 3.5 hose assembly hose with end fittings attached, complete with braid and/or other covering, ready for service 3.6 DN (nominal size) alphanumeric designation
19、 of size for components of a pipework system, is used for reference purposes NOTE It comprises the letters DN followed by a dimensionless whole number that is indirectly related to the physical size, in millimetres, of the bore or outside diameter of the end connections. ISO 6708:1995, definition 2.
20、1 3.7 rated pressure PR of a hose lowest Maximum Allowable Working Pressure (MAWP) of any component of the hose at 20 C 3.8 rated minimum temperature lowest temperature to which the hose assembly is rated by the manufacturer 3.9 cyclic life minimum number of complete cycles which, at the test condit
21、ions, the hose assembly is designed to withstand without failure 4 General requirements 4.1 Design and construction A hose is typically made from corrugated metal, from strip steel. The corrugation may be parallel or helical. If elastomers or composites are used, additional requirements shall be app
22、lied in accordance with 5.3.2.2. A braid is commonly fitted over the hose. 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 that shall be compatible with the surroundings and with the conveyed fluid. End fittings shal
23、l be designed as a rigid seal to the ends of a hose to ensure: a tight fit to the hose; a strong joint between the braid, hose and end fitting to stabilize the hose against elongation at rated pressure. Fittings for corrugated metal hose assemblies shall conform to ISO 10806. An area for marking sha
24、ll be provided on one of the end fittings. All joining methods used in corrugated hose assemblies shall be qualified. Manual welds shall be in accordance with applicable standards. BS ISO 21012:20063A typical cryogenic hose assembly is shown in Annex A. 4.2 Materials All materials shall be compatibl
25、e with the fluid conveyed and shall be controlled by the manufacturer of the hose assembly by a specification ensuring control of chemical content and physical properties, and quality at least equivalent to an internationally recognized standard. Materials for the manufacture of corrugated metal hos
26、e assemblies shall be selected on the basis of their suitability for fabrication, e.g. cold forming and welding, etc. and for the conditions under which they shall be used. In addition the following requirements shall meet: end connections and couplings shall be made of materials compatible with the
27、 other materials of the hose assembly; a test certificate providing the chemical content and physical property test results shall be provided with the hose assembly. The materials used in a cryogenic hose assembly shall: maintain sufficient ductility at the rated minimum temperature (as specified in
28、 ISO 21028-1); be oxygen compatible, if specified for oxygen or nitrous oxide service (as specified ISO 21010); contain less than 70 % copper, in the alloy as well as the soldering materials, if it is specified for mixtures containing acetylene. 4.3 Cleanliness Hose assemblies specified for all cryo
29、genic fluids shall be cleaned in accordance with ISO 23208. 4.4 Mechanical properties 4.4.1 Burst pressure The burst pressure shall be at least three times the rated pressure. Failure shall occur only in the body of the hose and braid and not in their connections. 4.4.2 Pressure cycles Hose assembli
30、es shall have a minimum cyclic life 10 000 cycles when repeatedly pressurized from 1 bar to their rated pressure in accordance with 5.3.1. 4.4.3 Bending Hose assemblies shall have a minimum cyclic life of 50 000 cycles when repeatedly flexed at their rated pressure in accordance with 5.3.2. 4.4.4 Re
31、sistance to abuse Hose assemblies should have sufficient resistance to deterioration of the braid when they are dragged on the ground. For additional protection of the braid a coil, can be used. Hose assemblies shall withstand a crushing test, simulating a person stepping on the hose assembly, in ac
32、cordance with 5.2.6. BS ISO 21012:20064 4.4.5 Leak tightness Hose assemblies shall be leak-tight in accordance with 5.2.4. 4.4.6 Electrical properties Hose assemblies specified for inflammable products shall be electrically conducting from one end to the other (electric resistance less than 10 ). 5
33、Hose sample tests 5.1 General The hose test samples shall be representative of production. The hose sample test procedures shall include: a) inspection and non-destructive tests: inspection: dimensions, cleanliness, material identification and marking; tests: pressure test, leak and crushing tests;
34、b) destructive tests: pressure cycling, bursting test, rolling bend cycling and examination of sectional cut. The tests shall be recorded in a written report which shall be retained for 10 y after the last hose has been placed on the market. Four sample hose assemblies (A, B, C and D) are necessary
35、to perform the tests. The tests and order of tests are summarized in Table 1. (The numbers 1 to 5 give the order of the tests). Table 1 Testing scope and sequence Hose Sample Tests A B C D 1: Non-destructive tests Documentation of materials Dimensional check Cleanliness check Pressure test Leak test
36、 Crushing test 1 1 1 1 2 1 1 1 1 4 2 1 1 1 1 3 1 1 1 1 2 2: Destructive tests Hydraulic pressure cycling Rolling bend cycling Hydraulic bursting test Examination of a sectional cut 3 4 3 5 2 4 3 BS ISO 21012:20065The hydraulic bursting test shall be carried out to qualify all DN hose assemblies. Whe
37、n a hose assembly with a given DN and a given rated pressure, PR, has been successfully sample tested, any hose assembly of the same type, having: a rated pressure u PR; a nominal diameter u 1,5 DN can be considered as approved except each DN hose assembly shall be hydraulic burst tested. A hose ass
38、embly is said to be of the same type when the design and its characteristics are similar to the tested hose; similarity is defined as having the same materials; welding method; type of corrugation (shape and method of manufacturing); method of joining (hose and end fitting); braid (type of braiding,
39、 i.e. calculated according to diameters to obtain the same maximum tensile stress in each wire, same materials, same welding method). Bend radius and minimum hose length for sample hose assemblies are defined in Annexes B and C. 5.2 Non-destructive tests and inspection 5.2.1 Documentation of materia
40、ls The materials, assembly methods, weld procedures and welder qualification for the manufacture of the hose assemblies shall be identified and documented. 5.2.2 Dimensional check The outside diameter and total length of hose assemblies shall be measured, as delivered, to check conformity with the d
41、rawings. 5.2.3 Cleanliness check The hose assembly shall satisfy the requirements of ISO 23208. 5.2.4 Pressure test All flexible hose assemblies shall be subjected to a hydraulic pressure test, at room temperature (20 10) C, equal to 1,5 the rated pressure. The pressure shall be held for a minimum o
42、f 3 min. There shall be no leaks. Under pressure, the overall length shall not increase by more than 3 %. As an alternative to the hydraulic test it is also permissible to perform a pneumatic test, at the same pressure, provided that the necessary safety precautions are met. 5.2.5 Leak test The hose
43、 assembly shall be leak tested by immersion in water and pressurized with gaseous nitrogen or air to the rated pressure. BS ISO 21012:20066 The pressure shall be maintained for a minimum of 5 min. There shall be no leaks detected (i.e. no release of bubbles of gas in water). This corresponds approxi
44、mately to a leak rate of less than 103mbar.l/s. Other methods of equivalent or greater accuracy may be used for standard hose assemblies. Hose assemblies specified for more stringent applications may have more stringent leak requirements (e.g. helium leak testing under pressure). 5.2.6 Crushing test
45、 This test shall be performed on hose assemblies to simulate risks of damage when walking on a hose. The hose assembly shall be held between two 200 mm 200 mm rigid plates and a force of 1 000 N shall be applied ten times at the same location in the middle of each flexible hose. The hose assembly sh
46、all then be examined to check if there is any pronounced damage caused by this test (a reduction in diameter greater than 20 % and appreciable damage to the braid is unacceptable). 5.3 Destructive tests 5.3.1 Hydraulic pressure cycling This test shall be carried out on one hose assembly of the teste
47、d lot with pressure cycling from 1 bar to rated pressure, at room temperature and at a frequency of 10 cycles per minute. The test shall be stopped at 10 000 cycles. There shall be no leakage in the hose during the test. 5.3.2 Rolling bend cycling test 5.3.2.1 Corrugated metal hose assemblies A roll
48、ing bend cycling test shall be carried out with the flexible hose assembly maintained at its rated pressure. The tests are described in Annex B. The test hose assembly shall undergo 50 000 cycles. There shall be no leakage in the hose during the test. 5.3.2.2 Hose assemblies constructed from non-met
49、allic materials or composites A rolling bend cycling test shall be carried out (with the addition of some induced torque and intermittent thermal shock) with the hose assembly maintained at its rated pressure. The tests are described in Annex C. The test hose assembly shall undergo 50 000 cycles. 5.3.3 Hydraulic bursting test The tested samples shall be pressurized up to rupture as follows: subject a straight, unconstrained sample assembly of mi
