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इंटरनेट मानक Disclosure to Promote the Right To Information Whereas the Parliament of India has set out to provide a practical regime of right to information for citizens to secure access to information under the control of public authorities, in order to promote transparency and accountability in the working of every public authority, and whereas the attached publication of the Bureau of Indian Standards is of particular interest to the public, particularly disadvantaged communities and those engaged in the pursuit of education and knowledge, the attached public safety standard is made available to promote the timely dissemination of this information in an accurate manner to the public. “जान1 का अ+धकार, जी1 का अ+धकार” “प0रा1 को छोड न’ 5 तरफ” Mazdoor Kisan Shakti Sangathan Jawaharlal Nehru “The Right to Information, The Right to Live” “Step Out From the Old to the New” IS 3745 (2006): Yoke Type Valve Connection for Small Medical Gas Cylinders [MED 16: Gas Cylinders] “!ान $ एक न’ भारत का +नम-ण” Satyanarayan Gangaram Pitroda ““IInnvveenntt aa NNeeww IInnddiiaa UUssiinngg KKnnoowwlleeddggee”” “!ान एक ऐसा खजाना > जो कभी च0राया नहB जा सकता हहहहै””ै” Bhartṛhari—Nītiśatakam “Knowledge is such a treasure which cannot be stolen” ,. Is 3745:2006 Indian Standard YOKE TYPE VALVE CONNECTIONS FOR SMALL MEDICAL GAS CYLINDERS — SPECIFICATION (Second Revision ) Ics 11.040.10 .... 0 BIS2006 BUREAU OF INDIAN STANDARDS MANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG NEW DELHI 110002 F April 2006 Price Group 7 GasCylinders Sectional Committee, ME 16 FOREWORD This Indian Standard ( Second Revision ) was adopted by the Bureau of Indian Standards, after the draft finalized by the Gas Cylinders Sectional Committee had been approved by the Mechanical Engineering Division Council. The revision of this standard has been prepared to align with the revision of 1S0 407 ; 1991 ‘Small medical gas cylinders — Pin-index yoke type valve connections’ including technical corrigendum 1ofNovember 1999. The scope of the revision has been extended to include outlet connection for medical air, outlet connection for nitrogen and for special mixture of 50percent nitrous oxide and 50percent oxygen. Inaddition single-in system has also been included in the revision. Assistance has also been taken from IS 3224:2002 ‘Valve fittings for compressed gas cylinders excluding liquefied petroleum gas ( LP-G) — Specification ( third revision )’ and [S 8737: 1995 ‘Valve fittings for use withliquefied petroleum gas ( LPG ) cylinders of more than 5 Iitre water capacity — Specification (jh-s[ revision )’. In the past, many accidents have occurred while handling medical gases by the administration of a wrong gas due to connecting the medical gas administering apparatus to awrong gas cylinder. This.standard seeks to lessen this risk by specifying a non-interchangeable system of valves for gas cylinders and anesthetic apparatus used in medical profession. The principal adopted isvery similar to that used with radio valves, whereby spacing of the pins on the valve ensure that each type can be inserted only inthe corresponding socket. The connection or yoke on the apparatus have pairs ofpins spaced in conformity with the holes on the valve outlet on the gas cylinder. By this means it will be impossible for a wrong cylinder ofgas to be connected to the administering apparatus. The composition of the Committee responsible for formulation ofthisstandard isgiven mAnnex B. ,,.. For the purpose of deciding whether a particular requirement of this standard iscomplied with, the final value, observed or calculated, expressing the result of a test or analysis, shall be rounded off in accordance with IS2:1960 ‘Rules for rounding off numerical values (revised )’. The number of significant places retained inthe rounded off value should be the same as that of the specified value in this standard. IS 3745:2006 Indian Standard YOKE TYPE VALVE CONNECTIONS FOR SMALL MEDICAL GAS CYLINDERS — SPECIFICATION (Second fevision ) 1 SCOPE [S No. Title Covers basic dimensions and constructional 319:1989 Free cutting leaded brass bars, rods requirements for yoke type valve connections for and sections ~ourth revision) smallmedicalgas cylinders with amaximum working 1068:1993 Electroplated coating nickel plus pressure (tilling pressure at 15“C)of 200 bars. Also chromium and copper plus nickel specifies the dimensions and positions for the holes plus chromium (third revision) and pins for the outlet connections for-medical gases and gas mixtures given inTable 1. 1598:1977 Methodforizodimpacttestofmetals (jirst revision) Table 1 Allocated Gases and Gas Mixtures 1608:2005 Metallic materials—Tensiletesting at ambient temperature (third sl No. Gas or Gas Nlixture Chemical revision) Symbol (1) (2-) (3) 2102 Generaltolerances:Part 1Tolerances i) Oxygen 02 (Part l): 1993 for linear and angular dimensions ii) Oxygen/Carbon dioxide (C02 < 02+ CC)2 without individual tolerance 7 percent) indications (third revision) iii) Oxygeo/Helium (HC<7 percent) 02+ He 2305:1988 Method for mercurous nitrate test iv) Ethylene C2Hd for copper and copper alIoys (Jrst \J) Nitrous oxide (without draw off) N20 revision) ,.,. vi) C.yclopropane C3H6 3224:2002 Valve fittings for compressed gas vii) Helium and helium/oxygen He cylinders excluding liquefied (02 <20 percent) petroleum gas (LPG) cylinders — viii) Carbon dioxide (with andwithout Col Specification (third revision) draw-off) and carbon dioxi d e/ oxygen (COj > 7 percent) 6912: 985 Copper and copper alloy forging ix) Medical air Air stock and forgings (f2rst revision) x) Nominal mixture 50 percent 02+N20 8775: 978 Fillingpressure and corresponding oxygen150 percent nitrous oxide developed.pressure for permanent (47.5 percent < N20 < 52.5 percent) gases contained in gas cylinders xi) Nitrogen N2 8866:1978 Filling ratios and corresponding xii) Mixture of air, helium and Air+ He+ CO developed pressure for high- carbon monoxide (CO < -pressure liquefiable gases 1 percent) contained in gas cylinders 8867:1978 Saturated vapour pressure and test 2 REFERENCES pressure forlowpressure liquefiable gases contained in gas cylinders The following standards contain provisions, which through reference in this text constitute provisions 3 MATERIAL ofthisstandard. Atthetimeofpublication,theeditions 3.1 Chemical Composition indicated were valid. All standards are subject to revision and parties to agreements based on this It shall be compatible with the gas to be contained standard areencouraged to investigate thepossibility in the cylinder. Actual chemical composition shall ofapplying the most recent editiohs ofthe standards be as agreed between the purchaser and the indicated below: manufacturer. 1 IS 3745:.2006 3.1.1 The valve body shall beofeither forged or 5 CONSTRUCTION machined from extruded section ofbrass. Atypical yoke assembly isillustrated inFig. 1. 3.1.2 The material of the valve body shall comply with the mechanical properties given in3.2. 3.I;3 Brass Components Brass components other than valve body shall -be made from free cutting brass rods (see IS 319) or from any forging quality brass such as leaded brass (see 1S-6912). 3.2 Mechanical Properties 3.2.1 Tensile Strength and Elongation The tensile strength and elongation of the material of the valve body determined according to IS 1608 shall not be less than 393.2 MPa (40 kgf/mm2) and 18percent measured on agauge length 5.65 @, (SO being the original area ofcross-section) respectwely. FIG. 1 TYPICAL YOKE ASSEMBLY 3.2.2 Impact Strength 5.1 Cylinder Valve The izod impact strength of valve body determined according to IS 1598, shall not be less than 21.5 J Each cylinder shall be fitted with a yoke valve (2.2kgf.m). (see 6) with a hole or holes of the dimensions and in the position or positions given in 8 for the 3.3 Test Samples appropriate gas. Samples for tensile and impact tests shall be taken 5.1.1 Theexternalsurfaceofthevalveshallbefinished from a valve blank, where practicable. Where not smooth and shall be free from sharp comers and practicable, test piece shall be subjected to same edges. Allvalves tobefitted with medical cylinders treatment as the valve so as to be representative of shallbebrightchromiumplatedconforming toService thematerial inthecondition inwhich ithastobeused. Condition No. 2asgiven inTable 3of IS 1068. The scale of sampling and criteria for conformity 5.1.2 Stress Corrosion Testfor Copper Alloy Valve shall be in accordance with the requirements of Bodies Annex A, unless otherwise agreed to between the manufacturer and the purchaser. Samples from batches of valve bodies shall be subjected tomercurous nitrate test inaccordance with 4 DESIGN IS 2305. The sample shall show no sign of cracking 4.1 Design Criteria after the test. 4.1.1 Valves shaIl be designed to operate under the 5.2 Yoke extreme conditions of environment, which could The yoke intended for fixing the housing apparatus cause a pressure rise in the cylinder contents up to to the valve shall conform to the dimensions given maximum developed pressure. in6.1and6.2. Twoalternative constructions asgiven 4.1.1.1 Design working pressure of the valve shall in 7.1 and 7.2 are also permissible. The yoke shall be the maximum developed pressure inthe cylinder befitted withapinorpins,thedimensionsandpositions atatemperature of 65°C incase of liquefiable gases ofwhichcorrespond totheholeorholes in-thevalves or the tilling pressure at 15°C incase of permanent and are given in8.1to8.11 for different gases or gas gases(see IS8775, IS8866 andIS8867). mixtures. 4.1.2 Materials for construction, including gaskets NOTE — InFig.2andinFig. 6to 16,tkcircle numbers are the pin hole positions. and seals, shall be compatible with each other, the gas contained, and the design temperature and 5.3 Types of ‘Valves and their Minimum pressure range of the valve. Constructional Requirements , 4.1.3 The components and parts of the valve of S.3.1 The valves shall have taper inlet threads same design of a same manufacturer shall be conforming to IS 3224 or any other threads may be interchangeable. used with the permission of the statutory authority. 2 IS 3745:2006 5.3.2 Valve outlet may be at any angle easily movement of the valve in the yoke to a accessible for connection. maximum of 6° about long axis prior to pin engagement. 5.3.3 Incasethe valves areoperated by means of rotating spindles, the spindles shall close the valves 7.2 First Alternative (see Fig. 4) bycl,ockwise rotation. Valve spindle may beat any 7.3 Second Alternative (see Fig. 5) angletotheinletthreads butitshallbeeasilyaccessible for closing and opening. 8 DIMENSIONS AND POSITIONS OF THE HOLES AND PINS FOR YOKE TYPE VALVE 5.3.4 Hand wheel orknob, wherever provided, shall CONNECTION beclearly marked with ‘Open’ and ‘Close’ positions inwords and in figures. 8.1 Outlet Connection for Oxygen (see Fig. 6) 5.3.5 The general machining tolerances unless 8.2 Outlet Connection for Oxygen/Carbon Dioxide otherwise stated shall of medium class specified in Mixtures (Carbon Dioxides 7percent) (see Fig. 7) lS2102(Part l). 8.3 Outlet Connection for Oxygen/Helium Mixtures 5.3.6 The minimum finished wall thickness at any (Helium S80 percent) (see Fig. 8) portion of the valve shall not be less than 2.5 mm. 8.4 Outlet Connection for Ethylene (see Fig. 9) However, this requirement shallberelaxed inthecase ofsectionsnotsusceptibletotamper,damageorrupture 8.5 Outlet Connection for Nitrous Oxide (see during use, or where any damage or rupture to the Fig. 10) section will not effect the sealing off, ofthe valve. 8.6 Outlet Connection for Cycle-Propane (see Fig. 11) 6 BASIC “DIMENS1ONS FOR YOKE TYPE VALVE CONNECTIONS 8.7 Outlet Connection for Helium/Oxygen Mixtures (Oxygen S20 percent) (see Fig. 12) The basic dimensions for pin-index yoke type valve connections.are shown inFig, 2 and Fig. 3. 8.8 Outlet Connection for Carbon Dioxide/Oxygen Mixtures (Carbon Dioxide 27 percent) (see Fig. 13) 6.1 Two-Pin System 8.9 Outlet Connection for Medical Air (see Fig. 14) 6.2 Single-Pin System 8.10 Outlet Connection for Special Mixtures of 7 ALTERNATIVE DESIGNS OF YOKE TYPE 50percent Nitrous Oxide and 50 percent Oxygen (see VALVE CONNECTIONS Fig. 15) 7.1 Requirement for the Design of C onnecting Yoke 8.11 Outlet Connection for Nitrogen (see Fig. 16) a) Agas-tight seal shall only bepossible when 9 INLET THREADS the pins inthe yoke correspond tothe holes Shallconform to8ofIS3224, unlessotherwise stated. in the valve; 10 HYDROSTATIC TESTS b) When the pins intheyoke donotcorrespond tothe holes inthevalve, agastight sealshall Representative -samples of machined valve bodies, not be possible and damage to the yoke or before assembly, shall be subjected to ahydrostatic the valve shall be prevented; test ataminimum test pressure equal to 1.5times the c) Pins shall be fixed or assembled in such a design working pressure of the valve that is the manner that they cannot be removed by the maximum pressure at which it is envisaged that the user or become loose inservice; valve will beused, subject toaminimum of 1.8MPa. The scale of sampling and the criteria of conformity d) Sealing washer shall bearetained fit onthe shallbethesameasthatadopted forthetensile strength yoke spigot; and elongation test of the Izod impact test unless e) Use of more than one sealing washer isnot otherwise agreed to between the manufacturer and permitted; the purchaser. 9 The yoke shall be able to resist, without 10.1 Design working pressure of the valve shal1be permanent deformation, the load resulting the maximum developed pressure inthe cylinder ata from a torque 50 Nm applied to the valve temperature of 65°C in case of liquefiable gases or clamping screw or locking device; and thefilling pressure at 15°Cincaseofpermanent gases g) The dimensions of the yoke shall limit the (see 4.1.1.1 ). 3 IS 3745:2006 TIT-%LR:? 3# ’ Al- 44.5 min. .. II ! II 44.5’min. 4.7:YAI ‘! I I I—- A +0.4 20 100” x-x o I .,,. All dimensions in millimetres. ‘1Applicable only if type safety is used. 2, Alternatively the yoke or the stabilizer shall be so dimensioned as to1tmitthe rotationofthe valve on the cylinder to 6° from vertical. J) May be reduced to 3.5 INM. If clearance is provided for proJ@@ safetY Plug. FIG. 2 TWO-PIN SYSTEM 4 -IS3745:2006 All dimensions inmi]]imetres FIG.3 SINGLE-PINSYSTEM .— I rnin2) 1 ~ 44.5min 3, .,,, — 1 8 min. All dimensions in millimetres. I)Applicable only if type safety is used. ‘) Alternatively the yoke orthestabitizer shall besodimensioned astolimit therotation of thevalve onthecylil]der to 6° from vertical. ~)-Maybe reduced to 3.5 mm. Ifclearance isprovided forprojecting safety plug. FIG.4 FIRSTALTERNATIVEDESIGNOFYOKETYPEVALVECONNECTION 5