1、 g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58cylinders Design, construction and testingICS 23.020.30Gas cylinders Refillable welded aluminium-al
2、loy BRITISH STANDARDBS ISO 20703:2006BS ISO 20703:2006This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 April 2007 BSI 2007ISBN 978 0 580 50520 1Amendments issued since publicationAmd. No. Date Commentssecretary.This publication does not pur
3、port to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.National forewordThis British Standard was published by BSI. It is the UK implementation of ISO 20703:2006. T
4、he UK participation in its preparation was entrusted by Technical Committee PVE/3, Gas containers, to Subcommittee PVE/3/3, Transportable gas containers Cylinder design, construction and testing at the time of manufacture.A list of organizations represented on PVE/3/3 can be obtained on request to i
5、ts Reference numberISO 20703:2006(E)INTERNATIONAL STANDARD ISO20703First edition2006-05-01Gas cylinders Refillable welded aluminium-alloy cylinders Design, construction and testing Bouteilles gaz Bouteilles rechargeables soudes en alliage daluminium Conception, construction et essais BS ISO 20703:20
6、06ii iiiContents Page Foreword. v Introduction . vi 1 Scope . 1 2 Normative references . 1 3 Terms, definitions and symbols 2 3.1 Terms and definitions. 2 3.2 Symbols . 2 4 Materials 4 4.1 General provisions . 4 4.2 Heat treatment. 4 4.3 Gas/material compatibility . 5 5 Design 5 5.1 General provisio
7、ns . 5 5.2 Calculation of wall thickness. 7 5.3 Design of convex ends (heads and bases) 8 5.4 Neck design. 12 5.5 Foot-rings 12 5.6 Neck-rings . 12 5.7 Shroud . 12 5.8 Design drawing . 12 6 Construction and workmanship 12 6.1 Seamless bodies. 12 6.2 Welding 12 6.3 Non-destructive examination of weld
8、s. 13 6.4 Surface defects . 13 6.5 Neck threads . 13 6.6 Out-of-roundness 14 6.7 Straightness 14 6.8 Eccentricity 14 6.9 Stability 14 7 Tests and examinations . 14 7.1 General. 14 7.2 Mechanical tests . 14 7.3 Hydraulic burst test 21 7.4 Pressure-cycling test 23 7.5 Hydraulic test 24 7.6 Check on th
9、e homogeneity of a batch 24 7.7 Leakage test 24 7.8 Capacity check 24 7.9 Examination for neck folds 24 8 Conformity evaluation 25 9 Identification marks 25 10 Records 25 Annex A (normative) Corrosion tests 26 Annex B (normative) New design type testing and production testing . 40 BS ISO 20703:2006i
10、v Annex C (normative) Description, evaluation of manufacturing defects and conditions for rejection of welded aluminium-alloy gas cylinders at time of visual inspection . 44 Annex D (informative) Examples of new design type approval and production test certificates 48 Bibliography . 54 BS ISO 20703:
11、2006vForeword 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 technical committees. Each member body interested in a subject for whic
12、h 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 closely with the International Electrotechnical Commission (IEC) on all ma
13、tters of electrotechnical standardization. International Standards 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 circ
14、ulated to the member bodies for voting. Publication as an International 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 respons
15、ible for identifying any or all such patent rights. ISO 20703 was prepared by Technical Committee ISO/TC 58, Gas cylinders, Subcommittee SC 3, Cylinder design. This International Standard has been prepared to address the general requirements in Section 6.2.1 of the UN model regulations for the trans
16、portation of dangerous goods ST/SG/AC.10/1/Rev.13. It is intended to be used under a variety of regulatory regimes but has been written so that it is suitable for use with the conformity assessment system in paragraph 6.2.2.5 of the above mentioned model regulations. BS ISO 20703:2006vi Introduction
17、 The purpose of this International Standard is to provide a specification for the design, manufacture, inspection and approval of refillable, transportable, welded aluminium-alloy gas cylinders. The specifications given are based on knowledge of, and experience with, materials, design requirements,
18、manufacturing processes and control during manufacture of cylinders in common use in the countries of the participating members. BS ISO 20703:20061Gas cylinders Refillable welded aluminium-alloy cylinders Design, construction and testing 1 Scope This International Standard specifies minimum requirem
19、ents for the material, design, construction and workmanship, manufacturing processes and tests at manufacture of refillable, transportable, welded aluminium-alloy gas cylinders of water capacities from 0,5 l up to and including 150 l, and of a test pressure not greater than 60 bar (6 MPa) for compre
20、ssed, liquefied and dissolved gases. This International Standard includes requirements for spherical receptacles and cylinders made from seamless bodies with welded non-pressure-bearing attachments such as shrouds and foot-rings. 2 Normative references The following referenced documents are indispen
21、sable 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 2107, Aluminium and aluminium alloys Wrought products Temper designations ISO 6506-1, Metall
22、ic materials Brinell hardness test Part 1: Test method ISO 6892, Metallic materials Tensile testing at ambient temperature ISO 7438, Metallic materials Bend test ISO 7866:1999, Gas cylinders Refillable seamless aluminium alloy gas cylinders Design, construction and testing ISO 9606-2, Qualification
23、test of welders Fusion welding Part 2: Aluminium and aluminium alloys ISO 10042:2005, Welding Arc-welded joints in aluminium and its alloys Quality levels for imperfections ISO 11114-1, Transportable gas cylinders Compatibility of cylinder and valve materials with gas contents Part 1: Metallic mater
24、ials ISO 11117, Gas cylinders Valve protection caps and valve guards for industrial and medical gas cylinders Design, construction and tests ISO 13341, Transportable gas cylinders Fitting of valves to gas cylinders ISO 13769, Gas cylinders Stamp marking ISO 15614-2:2005, Specification and qualificat
25、ion of welding procedures for metallic materials Welding procedure test Part 2: Arc welding of aluminium and its alloys BS ISO 20703:20062 3 Terms, definitions and symbols 3.1 Terms and definitions For the purposes of this document the following terms and definitions apply. 3.1.1 yield stress value
26、corresponding to the 0,2 % proof stress (non proportional elongation), Rp0,23.1.2 solution heat treatment thermal treatment which consists of heating the products to a suitable temperature, holding at that temperature long enough to allow constituents to enter into solid solution, and cooling rapidl
27、y enough to hold the constituents in solution 3.1.3 quenching controlled rapid cooling in a suitable medium to retain the solute phase in solid solution 3.1.4 artificial ageing heat treatment process in which the solute phase is precipitated to give an increased yield stress and tensile strength 3.1
28、.5 batch quantity of up to 250 cylinders, plus cylinders for destructive testing, of the same nominal diameter, thickness and design, made successively from the same cast and subjected to the same heat treatment for the same period of time; the lengths of the cylinders in the heat treatment batch ma
29、y vary by up to 12 % 3.1.6 design stress factor F ratio of equivalent wall stress at test pressure (ph) to guaranteed minimum yield stress (Re) 3.1.7 non-destructive examination examination or test that does not materially or adversely affect the item being examined 3.2 Symbols A percentage elongati
30、on, determined by the tensile test 7.2.3 a calculated minimum thickness, in millimetres, of the cylindrical or spherical shell a guaranteed minimum thickness, in millimetres, of the cylindrical or spherical shell b guaranteed minimum thickness, in millimetres, at the centre of a convex base Donomina
31、l outside diameter, in millimetres, of the cylinder, spherical cylinder or domed end (see Figure 2) Dinominal inside diameter, in millimetres, of the cylinder, spherical cylinder or domed end (see Figure 2) d diameter of former, in millimetres (see Figure 4) F design stress factor (variable) (see 3.
32、1.6) BS ISO 20703:20063hiinternal height, in millimetres, of semi-ellipsoidal or torispherical domed end (convex head or base end) (see Figure 2) hevariable used in the determination of shape factor, K (see 5.3.1) hoexternal height, in millimetres, of a semi-ellipsoidal or torispherical domed end (c
33、onvex head or base end) (see Figure 2) K shape factor for a semi-ellipsoidal or torispherical domed end, obtained according to the values he/Doand a/Do, with interpolation where necessary (see Figure 1) Looriginal gauge length, in millimetres, according to ISO 6892 n ratio of the diameter of the ben
34、d test former to actual thickness of test piece (t) pbmeasured burst pressure, in bar1)above atmospheric pressure phhydraulic test pressure, in bar1)above atmospheric pressure plclower cyclic pressure, in bar1)above atmospheric pressure pyobserved yield pressure which produces a permanent volumetric
35、 expansion of 0,2 %, in bar1)above atmospheric pressure Reminimum guaranteed value of yield stress (see 3.1.1), in megapascals, for the finished cylinder Reaactual value of yield stress, in megapascals, determined by the tensile test 7.2.3. Rgminimum guaranteed value of tensile strength, in megapasc
36、als, for the finished cylinder Rmactual value of tensile strength, in megapascals, determined by the tensile test 7.2.3 riinternal knuckle radius, in millimetres, of torispherical end see Figure 2c) ri internal radius, in millimetres, of dishing of torispherical end see Figure 2c) raexternal knuckle
37、 radius, in millimetres, of torispherical end see Figure 2c) ro external radius, in millimetres, of dishing of torispherical end see Figure 2c) sfstraight flange length, in millimetres, for semi-ellipsoidal and torispherical domed ends see Figure 2b) and 2c) Sooriginal cross-sectional area of tensil
38、e test piece, in square millimetres, according to ISO 6892 t actual thickness of test specimen, in millimetres tecalculated minimum thickness, in millimetres, of a domed end w width, in millimetres, of tensile test piece Vexpvolumetric expansion attained at burst, expressed as a percentage of the in
39、itial volume (see 7.3) Z stress reduction factor (see 5.2.1) 1) 1 bar = 105Pa = 105N/m2. BS ISO 20703:20064 4 Materials 4.1 General provisions 4.1.1 Aluminium alloys may be used to produce gas cylinders provided that they satisfy the requirements of the corrosion resistance tests defined in Annex A,
40、 and meet all other requirements of this International Standard. 4.1.2 Examples of the alloys most commonly used for the fabrication of gas cylinders are given in Table 1. 4.1.3 After the completion of all welding (including that of the attachments) and before the hydraulic test, each cylinder shall
41、 be heat treated if required to meet the design criteria. 4.2 Heat treatment 4.2.1 General Any welding on the pressure-bearing part shall take place before any final heat treatment (see 6.2). 4.2.2 Heat-treatable alloys The manufacturer shall specify on the new design type testing documentation, whe
42、re required, the solution heat treatment and artificial ageing temperatures and the times for which the cylinders have been held at those temperatures. The medium used for quenching after solution heat treatment shall be identified. Unless the alloy is subjected to a temperature in excess of 400 C d
43、uring the forming process, a stabilizing treatment shall be carried out and the temperature, and time at temperature, shall be identified by the manufacturer. However, the stabilizing treatment is not necessary for a cylinder of which the wall thickness in 5.2 is calculated with the minimum guarante
44、ed yield stress value of the O-tempered alloy (or the alloy annealed for complete re-crystallization before forming of cylinder, as defined in ISO 2107). If the cylinder is intended for dissolved-gas service it shall only be used in the fully annealed condition, i.e. the minimum guaranteed propertie
45、s used for the material shall consider the heat treatment to be applied, e.g. during the massing operation. 4.2.3 Non-heat-treatable alloys The manufacturer shall specify on the new design type testing documentation, where required, the type of metal forming operation carried out (extrusion, drawing
46、, ironing, head forming, etc.). Unless the alloy is subjected to a temperature in excess of 400 C during the forming process, a stabilizing treatment shall be carried out and the temperature, and time at temperature, shall be identified by the manufacturer. 4.2.4 Control of specified heat treatment
47、During the heat treatment, the manufacturer shall comply with the specified temperatures and durations, within the following ranges: a) Temperatures Solution temperature: maximum range 20 C Artificial ageing temperature: maximum range 20 C Stabilizing temperature: maximum range 20 C BS ISO 20703:200
48、65b) Durations Time cylinders actually spend at temperature during treatments: All treatments: maximum range 20 % 4.3 Gas/material compatibility Gas/material compatibility shall be verified as specified in ISO 11114-1. 5 Design 5.1 General provisions 5.1.1 The calculation of the wall thickness of th
49、e pressure-bearing parts shall be related to the yield stress (Re) of the material to ensure elastic behaviour. 5.1.2 For calculation purposes, the value of the yield stress (Re) is limited to a maximum of 0,9 Rgfor aluminium alloys. 5.1.3 The internal pressure upon which the calculation of wall thickness is based shall be hydraulic test pressure (ph). 5.1.4 For dissolved gases, the manufacturing process of the porous mass can modify the characteristics of the aluminium all