BRITISH STANDARD BS AU 110a 1995 Specification for Rubber hoses and hose assemblies for automotive air pressure braking systems UDC 629 3 02 592 5 62 462 036 4 BS AU 110a 1995 This British Standard, h[.]
BRITISH STANDARD Specification for Rubber hoses and hose assemblies for automotive air pressure braking systems UD C 62 02 - 592 5: 62 - 462 - 036 BS AU 110a: 1995 BS AU 110a:1995 Committees responsible for this British Standard The p rep aration of this Britis h S tandard was entrusted b y Technical C ommittee PRI/66, H os es , to S ub committee PRI/66/2 , H os es and tub ing for internal comb ustion engines, up on which the following b odies were rep resented: British Rub b er Manufacturers’ As sociation Ltd LP Gas As sociation Minis try of D efence S ociety of Motor Manufacturers and Traders Limited C o- op ted Memb ers This Britis h S tandard, having b een p rep ared under the direction of the S ector Board for Materials and C hemicals , was p ub lis hed under the authority of the S tandards Board and comes into effect on D ecemb er 9 © BS I 7- 9 Firs t p ub lis hed O ctob er 65 S econd edition D ecemb er 9 The following BS I references relate to the work on this s tandard: C omm ittee reference PRI /6 6/2 D raft for com ment 4/3 02 46 D C ISBN 580 24682 Amendments issued since publication Amd No D ate C omments BS AU 110a:1995 Contents Page Committees responsible Foreword ii Scope References Definition Types Construction Dimensions and tolerances Conditioning Performance Marking Annex A (normative) Ageing test Annex B (normative) Leakage under pressure Annex C (normative) Flexure test Figure A — Hose positioning for ageing test Figure C — Curved hose Figure C — Flexure test Table — Dimensions and tolerances of diameters Table — Minimum bend radius Table A — Dimensions of hose test pieces and former Table C — Dimensions for flexure test List of references © BSI 07- 999 Inside front cover Inside back cover i BS AU 1 a: 995 Fore word This British Standard has been prepared by Subcommittee PRI/66/2 It supersedes BS AU 1 0: 965, which is withdrawn This revision brings the specification broadly into line with SAE J1 402 [1 ] , a specification to which a proportion of this type of hose is manufactured in the UK, but this British Standard specifies higher operating temperatures The specification has been improved by the addition of several tests and more stringent requirements so that the standard more accurately reflects current demands and the product is better able to carry out its safety critical function 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 C omp liance with a British S tand ard d oe s no t of itse lf confe r immunity from le gal ob ligatio ns S ummary of p age s This document comprises a front cover, an inside front cover, pages i and ii, pages to 6, 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 the inside front cover ii © BSI 07- 999 BS AU 1 a: 995 c) a rubber cover resistant to oil and hydrocarbons, ageing and ozone This British Standard specifies the dimensions, The lining and cover shall be free from holes, construction and performance requirements for two porosity and other defects types of hose and hose assemblies used in all parts NOTE The hoses may be either mandrel or non-mandrel made of air pressure brake systems and finished smooth or fabric marked S cop e NOTE Both types are designed for operation at a maximum working pressure of 15.5 bar, and are distinguished by their recommended temperature ranges of operation D imensions and tole rance s D iame te rs Re fe re nce s Normative re fe re nce s This British Standard incorporates, by dated or undated reference, provisions from other publications These normative references are made at the appropriate places in the text and the cited publications are listed on the inside back cover For dated references, only the edition cited applies; any subsequent amendments to or revisions of the cited publication apply to this British Standard only when incorporated in the reference by amendment or revision For undated references, the latest edition of the cited publications applies, together with any amendments When measured in accordance with BS EN 24671 the internal and external diameters shall be as given in Table Limits on cut le ngths of hose NOTE The nominal length of hose should be specified by the purchaser When measured in accordance with BS 5173-101.2 the tolerance on cut lengths shall be ± % of the nominal length Minimum b e nd rad ius The minimum bend radius for installation shall be as given in Table Tab le — D ime nsions and to le rance s o f Informative re fe re nce s This British Standard refers to other publications that provide information or guidance Editions of these publications current at the time of issue of this standard are listed on the inside back cover, but reference should be made to the latest editions D e finitions For the purposes of this British Standard the definitions given in BS 3558 apply, together with the following d iame te rs Dimensions in millimetres No mi nal To le rance No mi nal To le rance i nte rnal o n i nte rnal e xte rnal o n e xte rnal d i ame te r d i ame te r d iame te r d i ame te r 6.3 10.0 12.5 14.0 16.0 hose asse mb ly hose with either permanent or reusable end fittings attached Typ e s There are two types of hose for use within the following temperature ranges: a) type A; for use within the temperature range – 40 °C to + 125 °C; b) type B; for use within the temperature range – 40 °C to 150 °C 0.40 ± 0.40 ± 0.50 ± 0.50 ± 0.50 16.0 19.0 22.2 25.4 27.0 ± 0.50 ± 0.50 ± 0.60 ± 0.60 ± 0.60 ± Tab le — Minimum b e nd radius Dimensions in millimetres No mi nal i nte rnal d i ame te r 6.3 10.0 12.5 14.0 16.0 Mini mu m b e nd rad i u s 64 89 102 108 114 C onditioning Tests given in to shall be carried out on test pieces taken from hoses or hose assemblies that have undergone the following water immersion The hoses shall consist of: a) a rubber lining with smooth bore and resistant conditioning The hose or hose assembly shall be immersed in to oil; distilled water at (23 ± 2) °C for (168 ± 2) h while b) a textile reinforcing layer or layers, plied, bent to the minimum bend radius given in Table braided or spirally wound; The hose ends and couplings shall be completely capped during immersion 8 1 C onstruction © BSI 07-1999 BS AU 1 0a:1 995 Performance 8.1 Resistance to ageing When tested in accordance with Annex A, the hose shall show no signs of cracking, charring or disintegration, either internally or externally 8.2 Low temperature flexibility When tested in accordance with method B of BS EN 24672:1993 at a temperature of (– 40 ± 2) °C, the hose shall show no signs of cracking when examined visually, and shall conform to 8.4 8.3 Change in length When tested in accordance with BS 5173-101.2, using an applied pressure of 15.5 bar1) , the maximum change in length shall be in the range – % to + % 8.4 Proof pressure test when tested in accordance with BS 5173-102.1 the hose or hose assembly shall not leak or show signs of failure at a hydrostatic pressure of 31 bar 8.8 Adhesion When tested in accordance with BS EN 28033, the load required to separate any layers shall be a minimum of 1.4 kN/m 8.9 Ozone resistance When tested in accordance with method of BS EN 27326:1993, no cracking shall be visible when the test specimen is examined under × magnification 8.1 Neutral salt spray test (applies to hose assemblies only) When tested in accordance with BS 7479 for (96 ± 2) h, the hose assembly shall show no base metal corrosion 8.1 Flexure test (applies to hose assemblies only) When tested in accordance with Annex C the hose assembly shall not fail before one million flex cycles have been completed Marking Each length of hose shall be durably marked at when tested in accordance with BS 5173-102.1 the intervals of not more than 250 mm with the hose or hose assembly shall not burst, leak or show following information: signs of failure at a hydrostatic pressure less a) manufacturer’s name or identification; than 62 bar b) number of this British Standard; 2) 8.6 Air leak c) type (A or B); When tested in accordance with Annex B the hose or d) nominal internal diameter; hose assembly shall show no leakage on visual e) quarter and year of manufacture; examination f) description “Air brake”; 8.7 Swell test g) batch reference number A test piece taken from both the lining and cover after immersion in oil no in accordance with BS 903-A16 at (100 ± 2) °C for (70 ± 2) h shall show MR/BSAU110a/A/16/3Q95/AIR BRAKE/BBB a volume increase of not more than 100 % 8.5 Burst pressure test Example: 1) bar = 100 kPa 2) Marking BS AU 110a:1995 on or in relation to a product represents a manufacturer’s declaration of conformity, i.e a claim by or on behalf of the manufacturer that the product meets the requirements of the standard The accuracy of the claim is solely the claimant’s responsibility Such a declaration is not to be confused with third party certification of conformity, which may also be desirable © BSI 07-1999 BS AU 1 0a:1 995 Annex A (normative) Ageing test A.2 Procedure Bend a length of hose around a former of the dimensions specified in Table A and hold in place A.1 Air oven (see BS 903- A1 9) by a band or cord (see Figure A ) The internal dimensions of the air oven shall not Place the assembly in the oven at the appropriate exceed (1 × × 5) m No copper or copper alloy temperature shown below for a period of (70 ± 2) h: shall be within the ageing chamber Provision shall type A 25 ° C be made for suspending test pieces so that they are type B 50 ° C not within cm of each other or of the sides of the After the ageing period take the assembly from the oven There shall be a slow circulation of air through the oven of not less than three changes in one hour The incoming air shall be heated to the temperature of the oven before coming into contact with the test pieces oven, allow it to cool to room temperature and remove the hose from the former Open out the hose to a straight length and cut lengthwise for examination Annex B (normative) Leakage under pressure Means shall be provided for controlling and measuring the rate of air flow The temperature of the oven shall be Connect the hose assembly, capped at one end, to a thermostatically controlled so that the test pieces source of air pressure Submerge the assembly in are kept within °C of the relevant ageing water, using any suitable container for the water temperature specified in A.2 A thermometer shall such that visual observation of the assembly is be placed amongst the test pieces to indicate the possible actual ageing temperature Apply an internal air pressure of 5 bar to the hose, maintaining the air pressure for at least Examine visually for leaks Table A.1 — Dimensions of hose test pieces and former Dimensions in millimetres Dimensions of test specimen Nominal internal diameter of Dimensions of former Length of hose Radius Height R hose Width A B Thickness C 229 38 114 76 13 0 254 45 20 89 19 279 51 27 02 19 305 57 40 114 22 305 57 40 114 22 Figure A.1 — Hose positioning for ageing test © BSI 07- 999 BS AU 1 0a:1 995 Annex C (normative) Flexure test b) After fitting has been coupled with the movable manifold, connect the fitting to the stationary manifold, X, without imparting any twist to the hose, but allowing the hose to seek its natural C.1 Preparation of test pieces C.1 Prior to cutting the hose, apply a layline (of a colour distinguishable from that of the hose cover) curvature C.4 Test procedure along the length of the hose following the natural Flexure/pressure cycling test parameters shall be as hose curvature which results from the hose being follows: coiled in a roll (see Figure C ) a) total flexure stroke (1 52 ± 6) mm; C.1 Cut the hose to provide a hose assembly test piece with a free hose length as shown in Table C Free hose length is the outside exposed hose length between the fittings in the finished hose assembly C.1 Assemble fittings to the hose in accordance with the manufacturer’s instructions to 27 °C; d) internal air pressure on test samples (1 ± ) bar Flex the test pieces by moving fitting from the C.2 Preconditioning Subj ect each hose test piece assembly to the neutral salt spray test described in 8.1 followed by heat ageing in an oven at (1 00 ± ) ° C for (70 ± 2) h with the hose assembly in a straight position C.3 Installation of test pieces in the test set up After preconditioning, install the assembly as shown in Figure C and proceed as follows, using configuration dimensions given in Table C a) With the movable manifold, Y, of the flex test machine at the centre of its stroke, connect fitting to the movable manifold in such a manner that the layline is located at the top- centre position (see Figure C 2) b) flexure stroke frequency (1 00 ± 5) cycles/min; c) ambient temperature in the range 21 ° C centre stroke position to 76 mm either side of centre (“A” dimension in Figure C 2) alternating between positions “1 ” and “2” while simultaneously cycling the air pressure on for 60 s and off for 60 s The air pressure shall be alternately fully “on” for (60 ± 5) s and fully “off” for (60 ± 5) s C.5 Failure point The failure point shall be determined by loss of air pressure through the failed test piece As the air pressure is alternately fully “on” for 60 s and fully off for 60 s, pressure loss shall be further described as failure of the system to be repressurized to (1 ± 7) bar through a ( +0 03 00 mm ) diameter orifice within 20 s Figure C.1 — Curved hose © BSI 07- 999 BS AU 1 a: 995 Figure C — Fle xure te st Tab le C — D ime nsio ns for fle xure te st Dimensions in millimetres No mi nal inte rnal Fre e ho se le ngth C o nfi gu ratio n/d i me nsio ns ± (1 mm) d iame te r Po si ti o n A B Po si tio n C R a A B C R 254 76 70 95 34 76 70 95 30 10 279 76 89 114 43 89 89 114 33 355 76 02 27 56 02 02 27 46 a a This is an approximate average radius © BSI 07- 999 blank BS AU 110a:1995 List of references (see clause 2) Normative references BSI publications BRITISH STANDARDS INSTITUTION, London BS 903, Physical testing of rubber BS 903- A1 6: 987, Determination of the effect of liquids BS 903- A1 9: 986, Heat resistance and accelerated ageing tests BS 3558: 980, Glossary of rubber terms BS 51 73, Methods of test for rubber and plastics hoses and hose assemblies BS 51 73- 01 , Determination of dimensions BS 51 73- 01 2: 987, Measurement of length of hoses and hose assemblies BS 51 73- 02, Hydraulic pressure tests BS 51 73- 02 : 991 , Hydrostatic tests BS 7479: 991 , Method for salt spray corrosion tests in artificial atmospheres BS EN 24671 : 993, Rubber and plastics hose and hose assemblies — Methods of measurement of dimensions BS EN 24672: 993, Rubber and plastics hoses — Sub-ambient temperature flexibility tests BS EN 27326: 993, Rubber and plastics hoses — Assessment of ozone resistance under static conditions BS EN 28033: 993, Rubber and plastics hose — Determination of adhesion between components Informative references Other publications [1 ] SAE J 402, Automatic air brake hose and hose assemblies 3) 3) Published by the Society of Automobile Engineers, 400 Commonwealth Drive, Warrendale PA 5096- 0001 USA © BSI 07- 999 BS AU 110a: 1995 BSI — British Standards Institution BS I is the indep endent national b ody res p ons ib le for p rep aring Britis h S tandards It p res ents the UK view on s tandards in E urop e and at the international level It is incorp orated b y Royal C harter Revisions Britis h S tandards are up dated b y amendment or revis ion Us ers of Britis h S tandards should make s ure that they p oss es s the latest amendments or editions It is the constant aim of BS I to imp rove the quality of our p roducts and services We would b e grateful if anyone finding an inaccuracy or amb iguity while us ing this Britis h S tandard would inform the S ecretary of the technical committee res p ons ib le, the identity of which can b e found on the inside front cover Tel: 02 89 96 90 00 Fax: 02 89 96 40 BS I offers memb ers an individual up dating s ervice called PLUS which ens ures that s ub s crib ers automatically receive the lates t editions of s tandards Buying standards O rders for all BS I, international and foreign s tandards p ub lications s hould b e addres s ed to C us tomer S ervices Tel: 899 00 Fax: 899 7001 In res p ons e to orders for international standards , it is BS I p olicy to sup p ly the BS I imp lementation of thos e that have b een p ub lis hed as Britis h S tandards, unless otherwis e requested Information on standards BS I p rovides a wide range of information on national, E urop ean and international standards through its Lib rary and its Technical H elp to E xp orters S ervice Various BS I electronic information s ervices are also availab le which give details on all its p roducts and s ervices C ontact the Information C entre Tel: 02 89 96 71 1 Fax: 02 89 96 048 S ub s crib ing memb ers of BS I are kep t up to date with s tandards develop ments and receive sub s tantial discounts on the p urchase p rice of s tandards For details of thes e and other b enefits contact Memb ership Adminis tration Tel: 02 89 96 70 02 Fax: 02 89 96 00 Copyright C op yright s ub s is ts in all BS I p ub lications BS I als o holds the cop yright, in the UK, of the p ub lications of the international s tandardization b odies E xcep t as p ermitted under the C op yright, D es igns and Patents Act 988 no extract may b e rep roduced, s tored in a retrieval s ystem or transmitted in any form or b y any means – electronic, p hotocop ying, recording or otherwis e – without p rior written p ermis s ion from BS I This does not p reclude the free us e, in the cours e of imp lementing the standard, of necess ary details such as s ymb ols, and size, typ e or grade designations If thes e details are to b e used for any other p urp os e than imp lementation then the p rior written p ermiss ion of BS I must b e ob tained If p ermis sion is granted, the terms may include royalty p ayments or a licensing agreement D etails and advice can b e ob tained from the C op yright Manager BS I 89 C his wick H igh Road London W4 4AL Tel: 02 89 96 70