1、BRITISH STANDARD BS 7122:1989 Specification for Welded steel tanks for the road transport of liquefiable gases UDC 629.11-445.6:66.076.5:661.91-404:621.642.2.036:621.772.46:669.14.018.29BS7122:1989 This British Standard, having been prepared under the direction of the Pressure Vessel Standards Polic
2、y Committee, was published under the authority of the Board of BSI and comes into effect on 31August1989 BSI 04-1999 The following BSI references relate to the work on this standard: Committee reference PVE/3 Draft for comment 82/70979 DC ISBN 0 580 17406 9 Committees responsible for this British St
3、andard The preparation of this British Standard was entrusted by the Pressure Vessel Standards Policy Committee (PVE/-) to Technical Committee PVE/3, upon which the following bodies were represented: Aluminium Federation Associated Offices Technical Committee Association of Manufacturers of Domestic
4、 Electrical Appliances British Compressed Gases Association British Fire Consortium British Fire Protection Systems Association Ltd British Railways Board British Soft Drinks Association Ltd Chief and Assistant Chief Fire Officers Association Department of Trade and Industry (National Engineering La
5、boratory) Department of Trade and Industry (National Physical Laboratory) Department of Trade and Industry Mechanical Engineering and Manufacturing Technology Division (Mmt) Department of Transport (Marine Directorate) Engineering Equipment and Materials Users Association Fire Extinguishing Trades A
6、ssociation Health and Safety Executive Home Office Industrial Safety (Protective Equipment) Manufacturers Association Institute of Refrigeration Institution of Chemical Engineers Liquefied Petroleum Gas Industry Technical Association (UK) Metal Packaging Manufacturers Association Ministry of Defence
7、 Society of Motor Manufacturers and Traders Limited Coopted members The following bodies were also represented in the drafting of the standard, through sub-committees and panels: Chemical Industries Association CEI/CSTI Joint Technical Committee Amendments issued since publication Amd. No. Date of i
8、ssue CommentsBS7122:1989 BSI 04-1999 i Contents Page Committees responsible Inside front cover Foreword ii Section 1. General 1 Scope 1 2 Definitions 1 3 Design, manufacture and testing of tanks 1 4 Information to be supplied by the purchaser and the manufacturer 1 5 Certificate of acceptance 2 Sect
9、ion 2. Materials 6 General 3 7 Identification 3 8 Condition 3 9 Analysis 3 10 Permissible materials 3 11 Impact and intercrystalline corrosion tests 4 Section 3. Design 12 General 5 13 Welds 8 14 Valves and fittings 8 15 Pressure relief devices 9 Section 4. Manufacture and workmanship 16 General 11
10、17 Tolerances 11 18 Post weld heat treatment 11 Section 5. Inspection and tests 19 General 12 20 Production control test plates 12 21 Pressure tests 12 22 Water capacity 12 23 Marking 12 Appendix A Typical acceptance certificate 13 Appendix B Side protection 14 Figure 1 Location of side protection r
11、elative to the horizontal centreline of the tank 14 Figure 2 Section of guard rail 14 Table 1 Impact values 4 Table 2 Intercrystalline corrosion test 4 Table 3 Design stress values for austenitic steel bars 5 Table 4 Design pressure for toxic gases in uninsulated tanks 6 Table 5 Design pressure for
12、non-toxic gases in uninsulated tanks 6 Table 6 Constant C for gas or vapour related to the ratio of specific heat capacities (K = C p /C v ) at standard conditions 10 Publications referred to Inside back coverBS7122:1989 ii BSI 04-1999 Foreword This British Standard has been prepared under the direc
13、tion of the Pressure Vessel Standards Policy Committee at the request of the Health and Safety Executive in order to satisfy the technical requirements of legislation. The committee responsible for the drafting of this standard had intended its publication to be part of the current British Standard
14、series of BS5045 (Transportable gas containers) but existing ADR, RID and/or IMG Codes already covered the use of gas containers transportation by road, rail or air and agreement was reached that a separate standard should be produced to meet industries needs for road transportation of welded steel
15、tanks. This British Standard, therefore, deals with welded steel tanks for road transportation of liquefiable gases and is not applicable to tanks which are transportable by air or sea. Also, in dealing with this type of tank, it excludes vacuum insulated tanks and drums from its scope, as well as l
16、imiting the portable tank capacity to1000L and over. This particular standard deals with the materials, design, construction and testing of new tanks for road tankers and tank containers used to transport liquefiable gases. This standard is to be used only in reference to transportable tanks used wi
17、thin the UK. 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. Summary of pages This docume
18、nt comprises a front cover, an inside front cover, pages i and ii, pages1 to 14, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on theinside front cover.BS7122:1989 BSI
19、 04-1999 1 Section 1. General 1 Scope This British Standard specifies requirements for the material, design, construction and testing of the tanks of road tankers used for the conveyance by road of liquefiable gases under pressure. It applies to steel tanks having manually and/or automatically welde
20、d circumferential and longitudinal seams. It does not cover vacuum insulated tanks and drums. This standard may also be used as a specification for the materials, design, construction and testing of portable tanks (e.g.the tanks of tank containers) with a capacity greater than1000L, in which case12.
21、6 and12.7 do not apply. In addition to the definitive requirements, this British Standard also requires the items detailed in clause4 to be documented. For compliance with this British Standard, both the definitive requirements and the documented items have to be satisfied. A model form of acceptanc
22、e certificate is given inAppendix A. The requirements for design, manufacture and testing of tanks are based on those specified for construction category1 components of BS5500 and as far as possible are covered by direct cross-references to the relevant requirements in sections 2, 3, 4 and 5 of BS55
23、00, and to the requirements of other relevant British Standards. NOTEThe titles of the publications referred to in this standard are listed on the inside back cover. 2 Definitions For the purposes of this British Standard, the definitions given in BS5355 and BS5500 apply. 3 Design, manufacture and t
24、esting of tanks The design, manufacture and testing of tanks shall be carried out to the satisfaction of the purchaser and the nominated inspecting authority which shall be independent of the manufacturer. 4 Information to be supplied by the purchaser and the manufacturer 4.1 General The following i
25、nformation to be supplied as appropriate by the purchaser or manufacturer shall be fully documented and, together with the definitive requirements specified throughout the standard, shall be satisfied before a claim of compliance with this standard can be made and verified. 4.2 Information to be sup
26、plied by the purchaser The following information is to be supplied: a) name or classification of gas(es) (seeBS5355); b) minimum service temperature and filling ratio at the prescribed reference temperature (seeBS5355); c) preferred dimensions and nominal (or minimum) volumetric capacity required; d
27、) positions of branches and other openings; e) material specification(s) and details of heat treatment condition(s) in which the material(s) is to be supplied (seeclauses6 and8); f) amount of corrosion allowance (if any) (see12.4); g) if additional material tests, e.g.ultrasonic examination and/or a
28、dditional certification of materials is required, the purchaser shall advise the manufacturer if the tests are to be witnessed by the purchasers representative or the inspecting authority; h) the type of examination to be carried out on welds to nozzles, branches and other attachments to the tanks (
29、seeclause19); i) any special or adverse conditions under which the tank will be required to operate; j) external/internal finish required; k) for tanks which are to be an integral part of a road vehicle, such information as necessary to suit the type of vehicle selected; l) the name of the inspectin
30、g authority. 4.3 Information to be supplied by the manufacturer Before commencing manufacture, the manufacturer shall submit for approval by the purchaser and the inspecting authority a fully dimensioned sectional drawing(s) showing in full detail the construction of the tank together with the follo
31、wing documented information. a) A statement that the tank shall be constructed in accordance with this standard and identifying the particular issue and update of BS5500 which will be used by the manufacturer where BS5500 is referred to in this standard and is not specifically dated. b) Specificatio
32、n(s) to which materials for each part shall conform, (seeclause6). c) Welding processes and procedures to be adopted for all parts of the tank.BS7122:1989 2 BSI 04-1999 d) Large scale dimensional details of the weld preparations for the longitudinal and circumferential seams and details of the joint
33、s for branch pipes, seating, etc., and the position of these joints relative to longitudinal and circumferential seams and other openings. e) Design pressure calculations. f) Test pressure calculations. No modification shall be made to the design, or any of the details provided as above, after appro
34、val by the purchaser and inspecting authority, except with the prior agreement between the purchaser, manufacturer and inspecting authority. The manufacturer shall supply to the purchaser for record purposes a copy of all the above information as finally approved. These records shall be retained by
35、the purchaser for the life of the tank. 5 Certificate of acceptance The manufacturer shall certify that the design, manufacture, inspection and testing of the tank were carried out in accordance with this standard. Where the design has been carried out by a separate organization from that which manu
36、factured and tested the tank, each organization shall certify that the work it has performed is in accordance with this standard. The inspecting authority shall certify acceptance of the above certification. NOTEA suitable form of acceptance certificate is shown inAppendix A.BS7122:1989 BSI 04-1999
37、3 Section 2. Materials 6 General The materials used for the tank or for any fittings welded to it shall be selected in accordance with section 2 of BS5500 relating to the selection of materials. Such materials shall not be adversely affected by the contents of the tank in such a way as to affect the
38、 suitability for its duty. NOTECertain steels are not suitable for ammonia service due to their susceptibility to stress corrosion cracking. In addition, for the purposes of this standard the following shall apply: a) permissible materials shall be in accordance with clause10; b) where steels to sim
39、ilar specifications to those given in clause10 are used, the requirements in section 2 of BS5500 relating to the use of materials not covered by listed British Standards shall apply. However, carbon steels which have a design stress at50C (calculated according to AppendixK of BS5500) exceeding250N/m
40、m 2 , or whose ratio of actual yield strength to actual tensile strength exceeds0.8 are not acceptable; c) the identification, delivery condition and analysis of material shall comply with clauses7, 8 and9; d) impact and intercrystalline corrosion tests shall be carried out as required by clause11.
41、7 Identification Each plate of steel supplied shall be marked with the number of the appropriate material standard to which it complies, including the grade number and letter, and with numbers or other identification marks by which it can be traced to the cast of steel from which it was made. If the
42、 plate is not supplied directly by the steelmaker to the tank manufacturer, then the material shall also be marked to identify the steelmaker. The marking shall be made by any means that does not result in stress raising notches. Where practicable other components shall be identified with the origin
43、al cast number. 8 Condition Plates of carbon steel or low alloy steel shall be supplied in the normalized condition except: a) plates to BS1501-1, types151,154,161 or164, which are6mm thick or less; or b) plates to BS1501-1, types223 or224, which are45mm thick or less, which shall be supplied in eit
44、her the normalized or the as-rolled condition. 9 Analysis The ladle analysis of materials shall be within the composition limits of the appropriate steel specification. In the event of one melt being divided between more than one ladle, samples shall be analysed from each ladle and a separate analys
45、is provided for each ladle. Each of these ladles shall subsequently be regarded as a specific cast and identified accordingly. Samples for product analysis shall be taken in accordance with BS1837 or ISO377. 10 Permissible materials 10.1 Carbon and low alloy steels 10.1.1 Plates. Tanks shall be manu
46、factured from one or more of the steels listed below unless otherwise agreed in accordance with itemb) of clause6: BS 1501-1 types 151, 154, 161, 164,223,224,225 BS 1501-2 types271,281 10.1.2 Other pressure parts. Materials for other pressure parts shall be selected from the list below unless otherw
47、ise agreed in accordance with itemb) of clause6: 10.2 Austenitic stainless steels 10.2.1 Plates. Tanks shall be manufactured from one or more of the steels listed below unless otherwise agreed in accordance with itemb) of clause6: BS 1501-3 types 304S12, 304S15, 316S12, 316S16, 316S37, 321S12,347S17
48、 Bars BS 1502 types 221, 224 Forgings BS 1503 types 223, 224, 271 Pipes and BS 3601 type S430 (fully killed) tubes BS 3602-1 types HFS430Cat2, CFS430Cat2 BS 3603 types HFS410 Cat2, CFS410Cat2 Bolting BS 4882 types L7, B7 (bolts) types L4,2H (nuts)BS7122:1989 4 BSI 04-1999 10.2.2 Other pressure parts
49、. Materials for other pressure parts shall be selected from the list below unless otherwise agreed in accordance with itemb) of clause6: 10.3 Nickel steels 10.3.1 Plates. Tanks shall be manufactured from one or more of the steels listed below unless otherwise agreed in accordance with itemb) of clause6: 10.3.2 Other pressure parts. Materials for other pressure parts shall be selected from the list below unless otherwise agreed in accordance with itemb) of clause6: 11 Impact and intercrystalline corrosion tests 11.1 Impact tests 11.1.1 Impact tests shall b
