1、BRITISH STANDARD BS 3212:1991 Specification for Flexible rubber tubing, rubber hose and rubber hose assemblies for use in LPG vapour phase and LPG/air installationsBS3212:1991 This British Standard, having been prepared under the directionof the Plastics and Rubber Standards Policy Committee, was pu
2、blished underthe authority of the Standards Board and comes intoeffect on 28June1991 BSI 12-1999 First published February 1960 Second edition October 1975 Third edition June 1991 The following BSI references relate to the work on this standard: Committee reference PRM/66 Draft for comment 89/47909 D
3、C ISBN 0 580 19664 X Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Plastics and Rubber Standards Policy Committee (PRM/-) to Technical Committee PRM/66, upon which the following bodies were represented: Association of Metropolitan Auth
4、orities British Coal Corporation British Compressed Gases Association British Gas plc British Rubber Manufacturers Association Chief and Assistant Chief Fire Officers Association Energy Industries Council Fire Extinguishing Trades Association Home Office Institution of Fire Engineers Liquefied Petro
5、leum Gas Industry Technical Association (UK) London Fire and Civil Defence Authority London Regional Transport Malaysian Rubber Producers Research Association Ministry of Defence Society of Motor Manufacturers and Traders Limited The following bodies were also represented in the drafting of the stan
6、dard, through subcommittees and panels: British Fluid Power Association Engineering Equipment and Materials Users Association Amendments issued since publication Amd. No. Date CommentsBS3212:1991 BSI 12-1999 i Contents Page Committees responsible Inside front cover Foreword ii 1 Scope 1 2 Definition
7、s 1 3 Classification and colour identification 1 4 Sampling and acceptance criteria 1 5 Temperature of testing 1 6 Type 1, flexible tubing for applications not exceeding50mbar working pressure 1 7 Type 2, hoses for applications not exceeding17.5bar working pressure 3 8 Connections for screwed ends 5
8、 9 Complete assemblies (hoses including connections) 5 10 Marking 5 Appendix A Test for strength, adhesion and stretch of tubing 6 Appendix B Test for resistance to kinking 6 Appendix C Test for burning behaviour 6 Appendix D Test for resistance to n-pentane 6 Appendix E Tests for resistance to crus
9、hing 6 Appendix F Test for flexibility 7 Appendix G Test for resistance to ozone 7 Appendix H Test for strength, stretch and ageing resistance of hoses and hose assemblies 7 Appendix J Test for resistance to burst 7 Appendix K Conditions prior to testing for resistance to flexing 7 Appendix L Safety
10、 recommendations 7 Figure 1 Metal nozzle for type1 (tubing) 2 Figure 2 Stretch test oversize metal nozzle for type1 (tubing) 2 Figure 3 Diagram illustrating kinking test 3 Figure 4 Test for burning behaviour 3 Figure 5 Nozzles for type 2 (hose) 4 Figure 6 Diagram illustrating flexing test 8 Table 1
11、Nominal bore of hose 3 Table 2 Spacing of the two points for the kinking test 6 Publication(s) referred to Inside back coverBS3212:1991 ii BSI 12-1999 Foreword This British Standard, prepared under the direction of the Plastics and Rubber Standards Policy Committee, is a revision of BS3212:1975 whic
12、h is withdrawn. The major changes from the1975edition are as follows. a) The colour identification requirements are more stringent. b) The marking clause requires the manufacturers name to be given instead of the suppliers name. c) Resistance to ozone is now carried out at40 C instead of at room tem
13、perature for both tubing and hose and the test sample is examined for cracks under a 2magnification. Appendix L details safety recommendations in the operation of tubing and hose/hose assemblies complying with this standard. A British Standard does not purport to include all the necessary provisions
14、 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 document comprises a front cover, an inside front cover, pages i and ii, pages1 to 8, an insid
15、e 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 the inside front cover.BS3212:1991 BSI 12-1999 1 1 Scope This British Standard specifies performance and dimensional requireme
16、nts for rubber tubing, hose and complete assemblies for use in LPG vapour phase and LPG/air installations in environments up to a maximum ambient temperature of60 C. NOTE 1Tubing and hoses specified in this standard should not be used for gas cutting and allied processes using oxygen unless they als
17、o comply with the requirements of BS5120. NOTE 2The abbreviation “LPG” (liquid petroleum gas) as used in this standard refers to butane and propane as defined in BS4250-1. NOTE 3The titles of the publications referred to in this standard are listed on the inside back cover. 2 Definitions For the pur
18、poses of this British Standard the definitions given in BS3558 apply. 3 Classification and colour identification 3.1 Classification Rubber tubing and hose shall be classified as follows. a) Type 1: flexible tubing for applications not exceeding50mbar 1)working pressure. b) Type 2: hoses for applicat
19、ions not exceeding17.5bar working pressure. 3.2 Colour identification Rubber tubing and hose shall be identified by colour as follows. a) Type 1 shall be black. b) Type 2 shall have an orange cover except hose supplied as a complete assembly with crimped or swaged ferrules for use in fixed LPG insta
20、llations where a black cover is permissible. 4 Sampling and acceptance criteria 4.1 Sampling The sample selected shall be representative of the consignment or batch supplied and of appropriate size for the number of test specimens required for testing. 4.2 Criteria for compliance If any of the test
21、specimens, taken from within the sample selected, fails to comply with this standard, two further samples from the same batch or consignment shall be taken for testing. If any of the test specimens in either of these additional samples fails, the batch or consignment represented by the samples shall
22、 be deemed not to comply with this standard. 5 Temperature of testing Unless otherwise specified, all tests shall be carried out at23 2 C. 6 Type 1, flexible tubing for applications not exceeding50mbar working pressure 6.1 General The materials used in the manufacture of the tubing shall be homogene
23、ous, free from odour, and resistant to outdoor exposure. The walls shall be seamless and free from all visible defects such as lumps, blowholes or cracks. The bore shall be clean and free from loose particles. NOTEAn appropriate metal nozzle for type1is shown in Figure 1. 6.2 Dimensions The bore of
24、the tubing shall be8 0.4mm. 6.3 Test sample A sample3m long shall be provided for test purposes. 6.4 Performance 6.4.1 Strength, adhesion and stretch When tested in accordance with Appendix A the tubing shall comply with the following requirements. a) It shall fit over the oversize nozzle shown in F
25、igure 2; b) It shall remain attached to both nozzles throughout the period of test; c) It shall show no signs of splitting or cracking and no leakage when tested at0.7bar air pressure under water for5min. 1) 1 mbar = 10 2N/m 2= 10 2Pa.BS3212:1991 2 BSI 12-1999 6.4.2 Resistance to pressure When immer
26、sed in water for5min under an internal air pressure of3.5bar, the increase in outside diameter shall be not more than15% and there shall be no sign of leakage. 6.4.3 Resistance to kinking When tested in accordance with Appendix B the gas pressure shown in the manometer shall drop by not more than10m
27、bar. NOTEA diagram illustrating a kinking test is shown in Figure 3. 6.4.4 Burning behaviour When tested in accordance with Appendix C the tubing shall not burn to either of the outer marks within45s. NOTEA test for burning behaviour is shown in Figure 4. 6.4.5 Resistance to n-pentane When tested in
28、 accordance with Appendix D the n-pentane absorbed shall not exceed15% of the initial mass of the tubing and the amount of n-pentane extractable matter shall not exceed10% of the initial mass of the tubing. 6.4.6 Resistance to crushing 6.4.6.1 When tested in accordance with E.1, with a crushing forc
29、e of125N, after removal of the force, the tubing shall not show subsequent deformation or collapse, nor shall it leak when subjected to an internal air pressure of0.75bar. 6.4.6.2 When tested in accordance withE.2, the gas flow rate shall be not less than0.07m 3 /h. 6.4.7 Flexibility When tested in
30、accordance with Appendix F no cracking of the tube shall occur. 6.4.8 Resistance to ozone When tested in accordance with Appendix G no cracks shall be visible. All dimensions are in millimetres. NOTEThe tolerance on all dimensions is 15 0.125 mm. Figure 1 Metal nozzle for type 1 (tubing) All dimensi
31、ons are in millimetres NOTEThe tolerance on all dimensions is 0.125 mm. Figure 2 Stretch test oversize metal nozzlefor type 1 (tubing)BS3212:1991 BSI 12-1999 3 6.4.9 Resistance to bending When tested in accordance with BS5173-103.5using a minimum radius of curvature of five times the outer diameter
32、of the test specimen, the deformation in the outside diameter shall be not greater than10%. 7 Type 2, hoses for applications not exceeding17.5bar working pressure 7.1 General The material used in the manufacture of the hose shall be free from odour. The hose lining shall be seamless and free from al
33、l visible defects and the hose shall contain a suitable reinforcement. Pricking of the hose cover shall not constitute a defect. The bore of the hose shall be clean and free from loose particles. NOTEAppropriate nozzles for type2are shown in Figure 5. 7.2 Dimensions of nominal bore When measured in
34、accordance with BS5173-101.1the bore of the hose shall be as given in Table 1. Table 1 Nominal bore of hose 7.3 Test sample A sample 5 m long shall be provided for test purposes. Dimension is in millimetres. NOTENot to scale. Figure 3 Diagram illustrating kinking test Dimensions are in millimetres.
35、Figure 4 Test for burning behaviour Nominal bore Allowed limits mm mm 4.8 0.5 6.3 0.6 8.0 0.8 10.0 0.8 12.5 0.8BS3212:1991 4 BSI 12-1999 7.4 Performance 7.4.1 Adhesion When tested by the method for type 1 described in BS5173-103.1, the adhesion between cover and reinforcement and between lining and
36、reinforcement shall be not less than1.5kN/m. 7.4.2 Strength, stretch and ageing resistance The hose shall fit over the appropriate nozzle shown in Figure 5 and the nozzle shall remain in the hose without leakage. The hose shall show no fractures, cracks or leakage when tested in accordance with Appe
37、ndix H. 7.4.3 Resistance to burst When tested in accordance with Appendix J the hose shall not burst at a pressure below52bar. 7.4.4 Resistance to kinking When tested in accordance with Appendix B the gas pressure shown on the manometer shall drop by not more than10mbar. 7.4.5 Burning behaviour When
38、 tested in accordance with Appendix C the hose shall not burn to either of the outer marks within45s. 7.4.6 Resistance of lining to n-pentane When the hose lining is tested in accordance with Appendix D the n-pentane absorbed shall not exceed15% of the initial mass of the lining and the amount of n-
39、pentane extractable matter shall not exceed10% of the initial mass of the lining. 7.4.7 Resistance to crushing 7.4.7.1 When tested in accordance with E.1, with a crushing force of340N, after removal of the force, the hose shall not show subsequent deformation or collapse, nor shall it leak when subj
40、ected to an internal air pressure of0.75bar. 7.4.7.2 When tested in accordance withE.2, the gas flow rate shall be not less than0.07m 3 /h. 7.4.8 Resistance to ozone When tested in accordance with Appendix G no cracks shall be visible. Nominal bore A B Dia. C Dia. D Dia. E Dia. F Rad. G Rad. H Rad.
41、J 5 25.0 6.4 3.2 4.5 5.0 5.94 1.0 1.0 0.4 6.3 25.0 8.0 4.8 6.2 6.3 7.95 1.3 1.3 0.4 8 25.0 8.7 6.3 6.9 8.0 9.04 1.5 1.5 0.4 10 38.0 8.7 7.9 8.6 9.5 11.1 2.0 2.0 0.4 12.5 38.0 12.0 8.7 11.6 12.5 14.3 2.5 2.5 0.4 NOTETolerance on all dimensions: 0.125 mm. Dimensions are in millimetres. Figure 5 Nozzle
42、s for type 2 (hose)BS3212:1991 BSI 12-1999 5 7.4.9 Permeability to propene When tested in accordance with BS5173-103.11using a test gas of minimum95% propene, in accordance with BS4947at cylinder pressure approximately0.6MPa (6bar) and standard laboratory temperature as defined in BS903-A35, the amo
43、unt of propene collected shall not exceed25mL/m per hour. 7.4.10 Resistance to bending When tested in accordance with BS5173-103.5using a minimum radius of curvature of five times the outer diameter of the test specimen, the deformation in the outside diameter shall be not greater than10%. 8 Connect
44、ions for screwed ends Connections shall be of fire resistant and corrosion resistant material, preferably of brass or steel. Design of the connections shall be such that the assembly can be secured at one end without the necessity of turning the hose relative to its mating piece and without the use
45、of additional fittings. NOTEOther aspects of the design should be agreed between the purchaser and the supplier. 9 Complete assemblies (hoses including connections) 9.1 General The hose shall be secured to end fittings by means of swageing, crimping or the use of suitable clips. Separate complete as
46、semblies shall be supplied for compliance with9.2.2 to9.2.5. 9.2 Performance 9.2.1 General In addition to testing of hose for compliance with7.4.1 and7.4.4 to7.4.9, assemblies shall be tested for compliance with9.2.2 to9.2.5. 9.2.2 Strength, stretch and ageing resistance Each of four assemblies shal
47、l show no cracks, flaws or leakage when tested in accordance with Appendix H. 9.2.3 Resistance to burst When tested in accordance with Appendix J the hose assembly shall not burst before sustaining a pressure of52bar. 9.2.4 Flexing resistance When subjected to conditions described in Appendix K, the
48、 assembly shall then withstand without leakage the unaged test described inH.1 toH.3, using an internal air pressure of26bar. 9.2.5 Resistance to bending When tested in accordance with BS5173-103.5using a minimum radius of curvature of five times the outer diameter of the test specimen, the deformat
49、ion in the outside diameter shall be not greater than10%. 10 Marking Each length of flexible tubing and hose shall be clearly and durably marked at intervals of not more than1m with the following information: a) the manufacturers name or identification; b) the number and date of this British Standard, i.e.BS3212:1991 2) ); c) the type number; d) the nominal bore; e) for type 1 tubing, LOW PRESSURE LPG, for type 2 hose, HIGH PRESSURE LPG; f) the month and year of manufacture; The information shall be stated in the form
