副本(1)[www.staffempire.com]-BS 1968-1953 Specification for floats for ballvalves (copper).pdf

BRITISH STANDARDBS 1968:1953Incorporating Amendment Nos.1 and 2Specification forFloats for ballvalves(copper)CONFIRMED DECEMBER 2007BS 1968:1953This British Standard,having been approved by the Sanitary Appliances Industry Standards Committee and endorsed by the Chairman of the Building Divisional Council,was published under the authority of the General Council on 8 May 1953 BSI 10-1999ISBN 0 580 35579 9Co-operating organizationsThe Sanitary Appliances Industry Standards Committee,under whose supervision this British Standard was prepared,consists of representatives from the following Government departments and scientific and industrial organizations:AdmiraltyMetal Sink Manufacturers AssociationBritish Bath Manufacturers AssociationMinistry of Housing and Local Government*British Ironfounders Association*Ministry of Works*British Plastics FederationNational Brassfoundry Association*British Sanitary Earthenware ManufacturersNational Federation of Building TradesAssociationEmployersBritish Sanitary Fireclay AssociationNational General Export Merchants GroupBritish Waterworks Association*Royal Institute of British Architects*D.S.I.R.Building Research Station*Royal Institute of Chartered SurveyorsFlushing Cistern Makers Association*Royal Sanitary Institute*Institute of Plumbers*Sanitary Inspectors AssociationInstitution of Municipal Engineers*Scottish Federation of Plumbers and DomesticInstitution of Sanitary EngineersEngineers(Employers)AssociationsLondon County CouncilWater Companies Association*The Government departments and scientific and industrial organizations marked with an asterisk in the above list,together with the following,were directly represented on the committee entrusted with the preparation of this British Standard:Associated Master Plumbers and DomesticCrown Agents for the ColoniesEngineersDistributors of Builders Supplies Joint CouncilAssociation of Heating,Ventilating andElectric Water Heater ManufacturersDomestic Engineering EmployersAssociationBritish Electrical Development AssociationInstitute of British FoundrymenBritish Electrical and Allied ManufacturersInstitution of Gas EngineersAssociationInstitution of Heating and VentilatingBritish Non-Ferrous Metals ResearchEngineersAssociationInstitution of Water EngineersBuilding Industries National CouncilLondon Chamber of CommerceB.W.A.Licensees AssociationMetropolitan Water BoardCopper Ball Manufacturers AssociationSociety of British Gas IndustriesCopper Tube Fittings ManufacturersUrban District Councils AssociationAssociationAmendments issued since publicationAmd.No.Date of issueComments3220November 19584667September 1962Indicated by a sideline in the marginw w w.b z f x w.c o mBS 1968:1953 BSI 10-1999iContentsPageCo-operating organizationsInside front coverForewordii1Scope12Definitions13General14Materials15Jointing of copper floats16Floats other than spherical27Bosses and fitments28Tolerances29Tests210Marking2Appendix Information to be supplied by the purchaser3Table 1 Spherical copper floats4Table 2 Classification of bosses for use withclasses A,B and C floats5Table 3a Bosses for classes A and C floats withsoldered and brazed joints6Table 3b Bosses for class B floats with solderless joints7Table 4 Weight of boss for classes A and C floats andof boss and fitments for class B floats8Table 5 Assembled weight of spherical copper floatsincluding solder or other jointing material8w w w.b z f x w.c o mBS 1968:1953ii BSI 10-1999ForewordThis standard makes reference to the following British Standards:BS 84,Screw threads of Whitworth form.BS 218,Brass bars and sections(suitable for forging)and drop forgings.BS 219,Soft solders.BS 427,Tables of diamond pyramid hardness numbers.BS 899,Cold rolled copper sheets and strip(half-hard and annealed)for general purposes.BS 1212,Ballvalves(“Portsmouth”type)excluding floats.BS 1400,Copper alloy ingots and castings.BS 1845,Filler alloys for brazing(silver solders and brazing solders).This British Standard specifies requirements for copper floats for use with ballvalves and has been issued to facilitate the manufacture as separate items,to be purchasable as such of floats suitable for ballvalves complying with the requirements of BS 1212,“Ballvalves(“Portsmouth”type)”and other types of ballvalve requiring floats of this description.Reference should be made to BS 1212 for permissible alternative types of float for use with ballvalves complying with that specification.For information regarding the correct size of float to use for a particular size of ballvalve,or range of pressure,where the leverage exerted is not less than that specified in BS 1212,reference should be made to Table 2 of this standard and also to BS 1212.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 pagesThis document comprises a front cover,an inside front cover,pages i and ii,pages 1 to 8,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.w w w.b z f x w.c o mBS 1968:1953 BSI 10-199911 ScopeThis British Standard specifies requirements for a range of spherical copper floatsof 41/2,5,6,7,8,9,10,11 and 12 inches nominal diameter suitable for attachment to the ballvalves specified in BS 1212 and to ballvalves the leverage of which for the same bore of seat is not less than that specified in BS 1212,in the following classes:Class A.Floats of all sizes with soldered joints.Class B.Floats of all sizes with solderless joints.Class C.Floats of all sizes with brazed,welded or silver-soldered joints.Performance requirements relating to floats of a shape other than spherical are also included.2 DefinitionsFor the purposes of this British Standard the following definitions shall apply:2.1 volumethe volume of water in cubic inches,taken to the nearest cubic inch,displaced when the shell(float with no boss)is completely immersed2.2 free-floating,volumethe volume of water in cubic inches,taken to the nearest cubic inch,displaced when the shell(float with no boss)is resting on water2.3 useful volumehalf the volume(see definition 2.1 above)less the free-floating volume(see definition 2.2 above)taken to the nearest cubic inch2.4 lifting effortthe useful volume(see definition 2.3 above)converted into weight in pounds at the rate of 0.036 lb.per cubic inch(Shown calculated in Table 1 for the minimum weight of shell.)2.5 maximum immersed operating depththe point at which the volume(see definition 2.1 above)is equally above and below the surface of the water2.6 diameter of spherical floatsthe average outside diameter of the shell measured at two axes at right angles to each other and clear of the jointing seam3 GeneralThe shells of copper floats shall comply with the requirements of Clauses 4,5,6,8,9 and 10,and shall be of the dimensions and weights given in Table 1.They shall be fitted with bosses complying with the requirements of Clause 7 and Table 2,Table 3a,Table 3b and Table 4.The complete float shall comply with the weight requirements ofTable 5 and shall not be artificially loaded for this purpose.After manufacture,the copper used for floats shall be left in a planished,condition and shall have a minimum Vickers hardness(HV)of 70 at any one point when tested with a 5 kgf load applied in accordance with the requirements of BS 427-11)Table 3.4 MaterialsThe chemical,composition of the materials of which the float is made shall be not less suitable than that laid down in the following British Standards:a)Copper for the shell:BS 899,“Cold rolled copper sheets and strip for general purposes”.b)Alloy for cast bosses:BS 1400,“Copper alloy ingots and castings”.Complying with either Specification BS 1400-B1-C for brass castings or for Specification BS 1400-LG2-C for leaded gunmetal castings.c)Alloy for hot pressed bosses:BS 218,“Brass bars and sections(suitable for forging)and drop forgings”.d)Solder:BS 219,“Soft solders”,complying with Type F,Table 2,“Non-antimonial solders”or BS 1845,“Filler alloys for brazing”,complying with the requirements for silver bearing brazing alloy,Types 4 or 5 or with the requirements for brazing brasses,Grades 8,9 or 10.5 Jointing of copper floatsThe jointing of the shells shall be in accordance with one of the methods given below,provided that when floats are required for use in water at a temperature exceeding 37.8 C.(100 F.)they shall be jointed as specified for Class C.The purchaser shall specify the method of jointing required.The methods of jointing are as follows:Class A floats.An efficient,burnished,lapped and soldered seam.1)BS 427,“Method for Vickers hardness test”,Part 1,“Testing of metals”.w w w.b z f x w.c o mBS 1968:19532 BSI 10-1999Class B floats.An efficient,solderless,compressed seam with a jointing ring of rubber or other equally suitable material,either extending right through the joint or otherwise arranged to prevent the joint ring from extruding into the shell and thus unsealing the joint.Class C floats.A brazed,bronze welded orsilver-soldered joint.6 Floats other than sphericalFloats of a shape other than spherical shall have a“lifting effort”at least equal to that of a spherical float intended for the same duty,as givenin Table 1,and shall be not less robust.7 Bosses and fitmentsBosses shall be either:a)Brass(pressed or forged).b)Cast brass(die cast or sand cast).c)Cast gunmetal.Fitments(rivets and washers or like methods of attachment)for Class B floats shall be either:a)Copper for rivets or washers.b)Brass for washers only.Every boss shall comply with one of the classifications set out in Table 2 and shall be in accordance with the appropriate dimensions given in Table 3a or Table 3b.The bottom of the tapped hole shall not extend through the flange.Spherical floats of all diameters shall be fitted with the appropriate size of tapped boss set outin Table 2,except that when so ordered the size of the tapping may be varied to suit special conditions.The boss shall be fitted to the shell in the following manner:Class A floats.The boss shall be located centrally astride the seam and shall be properly soldered to the shell.The soldering shall extend across the full width(see Dimension“H”,Table 3a)of the edge of the flange.A slot shall be cut in the flange of the boss to accommodate the seam of the shell.Class B floats.The boss shall be in accordance with Table 2 and Table 3b.The flange shall benon-recessed;it shall be shaped to suit the curved face of the shell,to which it shall be securely fixed,on an axis at right angles to the plane of the seam,by riveting or other equally efficient method.Class C floats.The alloy of which the boss is made shall be suitable for brazing.The boss shall be located centrally astride the seam and properly brazed to the shell.The brazing shall extend across the full width(see Dimension“H”,Table 3a)of the edge of the flange.A slot shall be cut in the flange of the boss to accommodate the seam of the shell.8 Tolerancesa)The volume of the shell shall be as given in Table 1,for each size,with a tolerance of 5 per cent.b)The minimum weights of copper shells of Classes A,B and C shall be as set out in Table 1.c)The weight and dimensions(excluding Dimension A)of bosses shall be as set out inTable 3a,Table 3b and Table 4 with a tolerance of 5 per cent.Dimension A shall be in accordance with the requirements of BS 84,“Screw threads of Whitworth form”.d)The minimum assembled weight of completed spherical floats,including solder or other jointing material,shall be as set out in Table 5,subject to the tolerances permitted under a),b)and c)above.9 TestsEvery finished float shall be tested by immersion for not less than two minutes,in water having a temperature of not less than 17 C.(30 F.)above the temperature of the surrounding air.There shall be no leakage of air from the float when so immersed.10 Marking2)Every float supplied as being in accordance with this British Standard shall be legibly and permanently marked with the information indicated below,in such a manner as not to damage or distort the float:a)Manufacturers name or trade mark.b)The number of this British Standard,i.e.BS 1968.2)A joint arrangement has been made between the British Waterworks Association and the BSI under which ballvalve floats made to this specification may be certified as complying with its provisions.Details of the conditions under which licences are issued for the use of the appropriate certification marks may be obtained from the Association,at 34 Park Street London,W.1.and from the British Standards Institution,at 2 Park Street,London,W.1.w w w.b z f x w.c o mBS 1968:1953 BSI 10-19993Appendix Information to be supplied by the purchaserThe purchaser shall supply the following information when making an enquiry,or placing an order:a)Size and class of floats required.b)The material for jointing,if Class C floats are required.c)The appropriate tapping of boss required(see Table 2 and Clause 7).w w w.b z f x w.c o mBS 1968:19534 BSI 10-1999Table 1 Spherical copper floatsNominal outside diameter of floatVolume of sphereClass AClass BClass CWeight of shell(min.)Free floating volumeUseful volumeLifting effortWeight of shell(min.)Free-floating volumeUseful volumeLifting effortWeight of shell(min.)Free floating volumeUseful volumeLifting effortin.41/256789101112cu.in.4865113180268382524697905lb.0.250.3280.4761.0741.4251.7822.1972.7553.207cu.in.7913304050617789cu.in.1723436094141201271363lb.0.610.841.562.163.385.077.239.7513.06lb.0.250.3280.4761.0741.4251.7822.1972.7553.207cu.in.7913304050617789cu.in.1723436094141201271363lb.0.610.841.562.163.385.077.239.7513.06lb.0.390.5150.8431.1871.8752.063.624.214.85cu.in.111423535257100117135cu.in.1318335782134162231317lb.0.460.651.192.052.954.825.838.3111.41NOTEThe lifting effort figures are calculated for the minimum weight of shell in each class.w w w.b z f x w.c o mBS 1968:1953 BSI 10-19995Table 2 Classification of bosses for use with classes A,B and C floatsClassification No.of bossDia.of flangeBS Whit.tappingAppropriate float diameter(if spherical)Sizes of BS 1212a ballvalve bodies with which floats are to be used123in.1 min.17/1613/4in.5/165/165/16in.41/2 and 567in.3/8,1/2 and 3/43A413/421/47/167/166 and 78 and 914A521/423/49/169/168 and 910 and 1111/4 and 11/25A23/45/810,11 and 1226With 2 straps5/812(alternative to 5A)a BS 1212,“Ballvalves(“Portsmouth”type)excluding floats”.w w w.b z f x w.c o mBS 1968:19536 BSI 10-1999Table 3a Bosses for classes A and C floats with soldered and brazed jointsDimensionDescriptionClassification number of boss1233A44A55A6AcBcCDcEaFaGHJbKBS Whitworth tapping of bossAxial length of threadDiameter of barrel or,if tappered,diameter of small endDiameter of flangeFace of flange to end of bossHe