1、BRITISH STANDARD BS ISO/TR 12391-1:2001 Gas cylinders Refillable seamless steel Performance tests Part 1: Philosophy, background and conclusions ICS 23.020.30 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBS ISO/TR 12391-1:2001 This British Standard, having been prepared unde
2、r the direction of the Engineering Sector Policy and Strategy Committee, was published under the authority of the Standards Policy and Strategy Committee on 17 January 2002 BSI 17 January 2002 ISBN 0 580 38050 5 National foreword This British Standard reproduces verbatim ISO/TR 12391-1:2001 and impl
3、ements it as the UK national standard. The UK participation in its preparation was entrusted by Technical Committee PVE/3, Gas containers, to Subcommittee PVE/3/3, Gas containers Design, which has the responsibility to: A list of organizations represented on this subcommittee can be obtained on requ
4、est to its secretary. Cross-references The British Standards which implement international publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Stand
5、ards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers
6、to understand the text; present to the responsible international/European 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
7、comprises a front cover, an inside front cover, the ISO title page, pages ii to v, a blank page, pages 1 to 13 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 Reference number
8、ISO/TR 12391-1:2001(E) ISO1002 TECHNICAL REPORT ISO/TR 12391-1 First edition 2001-12-15 Gas cylinders Refillable seamless steel Performance tests Part 1: Philosophy, background and conclusions Bouteilles gaz Rechargeables en acier sans soudure Essais de performance Partie 1: Philosophie, historique
9、et conclusions ii ISO/TR 12391-1:2001(E) iiiContents Page Foreword.iv Introduction.v 1 Scope 1 2 References .1 3 Terms and definitions .1 4 Symbols and abbreviations2 5 Background2 6 Considerations of fracture performance.6 7 Flawed cylinder burst test procedure8 8 Considerations of fatigue cycle te
10、st8 9 Discussion of test data .9 Bibliography12 ISO/TR 12391-1:2001(E) iv Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO te
11、chnical 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 with ISO, also take part in the work. ISO collaborates close
12、ly 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 3. The main task of technical committees is to prepare International Standards. Draft
13、 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. In exceptional circumstances, when a technical committee has collected data of
14、 a different kind from that which is normally published as an International Standard (“state of the art”, for example), it may decide by a simple majority vote of its participating members to publish a Technical Report. A Technical Report is entirely informative in nature and does not have to be rev
15、iewed until the data it provides are considered to be no longer valid or useful. Attention is drawn to the possibility that some of the elements of this part of ISO/TR 12391 may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO/TR 1
16、2391-1 was prepared by Technical Committee ISO/TC 58, Gas cylinders, Subcommittee SC 3, Cylinder design. ISO/TR 12391 consists of the following parts, under the general title Gas cylinders Refillable seamless steel Performance tests: Part 1: Philosophy, background and conclusions Part 2: Fracture pe
17、rformance tests Monotonic burst tests Part 3: Fracture performance tests Cyclical burst tests Part 4: Flawed cylinder cycle test ISO/TR 12391-1:2001(E) vIntroduction Gas cylinders as specified in ISO 9809-1 have been constructed of steel with a maximum tensile strength of less than 1 100 MPa. With t
18、he technical changes in steel-making using a two-stage process, referred to as ladle metallurgy or secondary refining, significant improvement in mechanical properties have been achieved. These improved mechanical properties provide the opportunity of producing gas cylinders with higher tensile stre
19、ngth, which achieve a lower ratio of steel to gas weight. The major concern in using steels of higher tensile strength with correspondingly higher design wall stress is safety throughout the life of the gas cylinder. When ISO/TC 58/SC 3 began drafting ISO 9809-2, Working Group 14 was formed to study
20、 the need for additional controls for the manufacture of steel gas cylinders having a tensile strength greater than 1 100 MPa. This part of ISO/TR 12391 presents the philosophy and background information developed by WG 14 to study the problems inherent with steel of higher tensile strength. It also
21、 states the conclusions of WG 14, which were included in ISO 9809-2. blankTECHNICAL REPORT ISO/TR 12391-1:2001(E)1Gas cylinders Refillable seamless steel Performance tests Part 1: Philosophy, background and conclusions 1 Scope This part of ISO/TR 12931 applies to seamless steel refillable cylinders
22、of all sizes from 0,5 l up to and including 150 l water capacity produced of steel with tensile strength (R m ) greater than 1 100 MPa. It can also be applied to cylinders produced of steels used at lower tensile strengths. In particular, it provides the technical rationale and background to guide f
23、uture alterations of existing ISO standards or for developing advanced design standards. 2 References ISO 6406.1992, Periodic inspection and testing of seamless steel gas cylinders ISO 9809-1:1999, Gas cylinders Refillable seamless steel gas cylinders Design, construction and testing Part 1: Quenche
24、d and tempered steel cylinders with tensile strength less than 1 100 MPa ISO 9809-2:2000, Gas cylinders Refillable seamless steel gas cylinders Design, construction and testing Part 2: Quenched and tempered steel cylinders with tensile strength greater than or equal to 1 100 MPa 3 Terms and definiti
25、ons For the purposes of this part of ISO/TR 12391, the following terms and definitions apply. 3.1 flawed cylinder burst test test conducted on a finished gas cylinder having a deep prescribed flaw machined into the exterior sidewall and failed by internal pressurization NOTE Pressurization can be hy
26、draulic, applied either monotonically or cyclical. The flaw depth is in the range of 75 % of the cylindrical wall thickness. 3.2 flawed cylinder cycle test test conducted on a finished gas cylinder having a shallow prescribed flaw machined into the exterior sidewall and failed by cyclical internal p
27、ressurization NOTE Pressurization is normally hydraulic. The flaw depth is 10 % of the cylindrical wall thickness. 3.3 fracture performance type of crack growth at the instant of through-wall failure, either by stable crack arrest or a running crack rupture, i.e. leak or fracture ISO/TR 12391-1:2001
28、(E) 2 4 Symbols and abbreviations 4.1 Symbols d = artificial flaw depth (mm), D = nominal outside diameter of cylinder (mm), l o = length of artificial flaw (mm), P f= measured failure pressure (bar), P h= hydrostatic test pressure (bar), P s= calculated design working pressure (bar), t a = actual m
29、easured wall thickness at the location of the flaw (mm), t d = calculated minimum design wall thickness (mm), R e= actual measured value of yield strength (MPa), R m = actual measured value of tensile strength (MPa) 4.2 Abbreviations CVN = charpy V-notch impact test KIC = keyhole impact charpy LBB =
30、 leak before break fracture performance UTS = ultimate tensile strength NOTE In ISO/TR 12391-2 1)this term is to be defined as either “leak” or “fracture”. 5 Background 5.1 Participation In 1989 ISO/TC 58/SC 3 formed a working group (WG 14) to study the potential need for controls in excess of those
31、 in ISO 9809-1 for the manufacture and testing of steel cylinders with tensile strengths greater than 1 100 MPa. Extensive technical considerations were essential to the development of an ISO standard for the production of a new generation of cylinders using higher tensile strengths to assure safe p
32、erformance during their service life. A primary concern was the potential fatigue crack failure mechanism. Seven member nations provided one or more technical members who had expertise in the technology of seamless steel gas cylinders. These countries and companies are listed in Table 1. 1) In prepa
33、ration. ISO/TR 12391-1:2001(E) 3Table 1 List of participating countries Country Company Status Austria J. Heiser Producer Air Liquide User France Valmont Producer Germany Mannesmann Producer JISC Regulator Japan Sumikin Kiko Producer Sweden AGA User United Kingdom Chesterfield Producer Norris Cylind
34、er Co. Producer Praxair User Pressed Steel Tank Co. Producer Taylor Wharton Producer U.S. DOT Regulator USA National Institute of Science 950 to 1 100 Mpa; greater than 1 100 MPa. Table 2 lists existing controls, which affect fracture performance, presented by Austria, France, Sweden, United Kingdom
35、 and USA in 1989. It was noted that these basic controls were similar in all nations and used traditional metallurgical factors. In 1989 only Austria and the USA had developed specific controls for steel with a tensile strength above 1 100 MPa. In addition to the data given in Table 2, various exper
36、ts put forth other considerations. Austria presented a procedure for predicting burst versus leak in a cycle/fatigue test. France presented the classic French burst test with a statistical time-history along with impact test data. Sweden stated that an increase in Charpy values would normally be req
37、uired to assure adequate toughness at the increased strength level. The United Kingdom presented a concept of a hydro-burst test measuring total energy and presented a paper on that concept. Germany investigated the “Battelle Concept” and pointed out that those equations were only valid where the ma
38、terial exhibits ductile fracture behaviour, and the calculations are not applicable to brittle fracture or mixed fracture mode. The USA presented a procedure applied since 1985 for cylinders with tensile strength over 1 100 MPa, and test data from two manufacturers for the “Leak-before-break” (LBB)
39、test concept on a pre-flawed cylinder. ISO/TR 12391-1:2001(E) 4 Figure 1 Flow chart of issues, objectives and approach It was concluded that the only significant change in cylinder performance at strength levels above 1 100 MPa would be the potential reduction in toughness because of the substantial
40、 increases in tensile strength. Consequently, it was agreed that the critical control factor required was “To develop toughness acceptance level and test procedures for steel used in the construction of seamless cylinders with tensile strength above 1 100 MPa to assure a fracture safe performance”.
41、It was further agreed that current state-of-the-art control of fracture performance could be achieved by a flawed cylinder burst test and a Charpy V-notch test in the transverse direction at 50 C. An important consideration was to develop a test that tested the entire cylinder and not merely test sa
42、mples taken from the cylinder wall. At a later stage the work programme of WG 14 was extended to include a further test to control safe service performance and fatigue cycle life. As a consequence of this study, the flawed cylinder cycle test was adopted in ISO 9809-2. Table 2 Fracture control Curre
43、nt practices 1989 Member nation and strength level Control factor Sweden France Austria UK USA R m(N/mm 2 ) 1 100 All strengths 950/1 150 1 150 u 1 030 u 1 070 W 1 100 u 950a950/1 070 1 070/1 200 R e /R m b u 0,9 for H 2 u 0,95 other b Elongation 14 % 14 % (ISO) bW 16 % (5d gauge) W 14 % (ISO) W 12
44、% (ISO) W 14 % (ISO) W 14% bW 20 % 2 in 1,5 in gauge W 16 % 2 in 1,5 in gauge W 12 % 2 in 1,5 in gauge Burst P b /P h= NR P b /P hW 1,6 bP b /P hW 1,67 In accordance with ISO P b= In accordance with ISO P b= In accordance with ISO P b= bc Flawed burst Burst fracture appearance NR NR b Propagation in
45、to thicker section u 1,2 t No limit on propagation length No limit on propagation length b L/temperature 50/50 C 50/50 C b50/20 C 60/20 C 50/20 C 40/20 C bd 58/18 C CVN (J/cm 2 ) T/temperature b For t 5mm 25/20 C 25/20 C b 44/ 18 C KIC bCVN KIC b W 85 Ksi aUSA limited R mto 930 N/mm 2for hydrogen an
46、d embrittling gases. bNo specific control. cBurst test not required as production test; but US DOT requires maximum of 2,5 P s(1,5 P h ) for standard 3A and 3AA. dCVN not required as production test, however industry control limits are 51 J/cm 2 , L at 50 C and average 102 J/cm 2 , L at 50 C. ISO/TR
47、 12391-1:2001(E) 5ISO/TR 12391-1:2001(E) 6 6 Considerations of fracture performance 6.1 General WG 14 members conducted a series of tests on cylinders of different tensile strength levels. These included: all strength ranges of existing cylinders; existing cylinders re-heat treated to higher strengt
48、h levels; cylinders with a tensile strength greater than 1 100 MPa. Each cylinder test was to include: the flawed cylinder burst test; CVN impact tests transverse at 50 C; a standard tensile test. Figure 2 shows the standardized test data report required to be used by each participant. By standardiz
49、ing both the test methods and the required data collection report, the results of the tests performed at various locations were suitable for compilation, comparison and analysis. A basic premise in studying the flawed cylinder burst test was that testing a finished cylinder under service stress conditions instead of testing samples extracted from a cylinder would be a far superior method to stimulat
