[www.staffempire.com]-BS 1212-1-1990 Float operated valves. Specification for piston type float operated valves.pdf

BS 12 12:Part 1:1990 UDC 621.646.61 8:621.646.2-3 14.1:669.35 5 0 British Standards Institution.No part of this publication may be photocopied or otherwise reproduced without the prior permission in writing of BSI British Standard Float operated valves Part 1.Specification for piston type float operated valves(copper alloy body)(excluding floats)Robinets a flotteur Partie 1.Robinets a flotteur de type piston(corps en alliage de cuivre)(a Iexclusion des flotteurs)-Specifications Sc h wi m merven t i I e Teil 1.Kolbenschwimmerventile(mit Gehause aus Kupfer)(ausgenommen Schwimmer)British Standards Institution Licensed copy:PONTYPRIDD COLLEGE,13/02/2008,Uncontrolled Copy,BSI BS 1212:Part 1:1990 Foreword This Part of BS 1212 has been prepared under the direction of the Building Services Standards Committee and specifies requirements for piston type float operated valves(exclud-ing floats).It supersedes BS 1212:Part 1:1953,which is withdrawn.The new features in this Part of BS 1212 include the following:(a)the possible production of certain components from plastics materials;(b)an extension of the range of sizes of plastics seats;(c)a seat numbering system;(d)a bottom entry inlet connection and its associated inlet elbow,with adjustable stay;(e)a recognition of the greater lifting effort of plastics floats over copper floats of equivalent size;(f)the supply of size 3/8 and size 12 levers with a downturn portion fitted with a float adjuster and thumb screw;(9)a further method of production for two piece levers(h)a test for plastics backnut strength,in line with BS 1212:Part 3;(j)a test for plastics locknut strength;(k)a recognition of current manufacturing practice by deletion of reference to the use of agate tipped seats.Due to the fact that valves covered by this Part of BS 1212 do not provide the appropriate backsiphonage protection required by the Water Byelaws,it is recommended in the case of nominal size valves that a valve covered by one of the other Parts of BS 1212 be used for applications where backsiphonage protection is required.Alternatively,a valve covered by BS 1212:Part 1 can be used in these cases if a suitable protective device is connected to the feed piper to the valve.For nominal size%and above,such a device should be used whenever backsiphonage protection is required.Advice on suitable protective devices is given in the Water Research Centre publication Water Fittings and Materials Directory and in BS 6700.This Part of BS 1212 has been revised in metric terms,except for certain thread sizes and pipe thread designations which are retained in imperial sizes to accord with BS 2779.Compliance with a British Standard does not of itself confer immunity from legal obligations.Licensed copy:PONTYPRIDD COLLEGE,13/02/2008,Uncontrolled Copy,BSIw w w.b z f x w.c o mBS 1212:Part 1:1990 Contents Foreword Com m ittees res pons i ble Page Inside front cover Back cover Specification Section one.General 1 Scope 2 Definition 3 Designation for ordering 4 Marking Section two.Materials 5 Quality and finish 6 Plastics 7 Castings 8 Hot stampings 9 Mouldings 10 Machining Section three.Design,construction and dimensions 11 General 12 Screw threads 13 Inlet connection 14 Backnuts 15 Bodies 16 Body coupling nuts 17 Body end caps 18 Pistons and piston washers 19 Seats 20 Levers 21 Locknuts for levers 22 Float adjusters and thumb screws 23 Split cotter pins Section four.Performance 24 Hydraulic pressure and shut-off 25 Backnut distortion 26 Locknut distortion 27 Mechanical strength of levers Appendices A Method of test for shut-off when assembled with appropriate float 2 2 2 2 3 3 3 3 3 3 5 5 6 6 6 6 6 6 7 7 7 8 8 9 9 9 9 30 B Method of test for distortion of size /z plastics backnuts C Method of test for distortion of plastics locknuts D Method of test for mechanical strength of levers E Discharge of water through piston type float operated valves Tables 1 Materials 2 Body,seat and float combination 3 Side entry inlet shank and inlet for connection to 12 mm and 15 mm copper tube 4 Type(a)backnuts(integral flange)5 Type(b)backnuts(spigoted)6 Type(c)backnuts(fixed flange)7 Bodies 8 Body coupling nuts 9 Body end cap 10 Pistons and piston washers 11 Seats and joint ring for seats 12 Seat numbers 13 Levers 14 Test loads for levers 15 Computed flow through seat orifices Figures 1 Section of typical size /z piston type float operated valve with detail of inlet and alternative lever arm 2 Inlet shanks 3 Inlet elbows 4 Backnuts 5 Bodies 6 Body coupling nuts 7 Body endcap 8 Pistons and piston washers 9 Seats and joint ring for seats 10 Levers and socket for soldered joint for two piece levers 11 Float adjuster,thumb screw and split cotter pin Page 30 30 30 30 4 5 12 15 15 15 17 19 20 21 25 25 27 30 32 9 11 13 14 16 19 20 21 23 27 29 1 Licensed copy:PONTYPRIDD COLLEGE,13/02/2008,Uncontrolled Copy,BSIw w w.b z f x w.c o m I I Specification.Section one BS 1212:Part 1:1990 I I Section one.General 1 Scope This Part of BS 1212 specifies materials,dimensions,tolerances and performance requirements for piston type float operated valves(copper alloy body)of nominal sizes 3/8,/z ,3/4,1,1 14,1 h and 2 with six patterns of body,designated I,II,Ill,IV,V and VI,intended for use with floats complying with BS 1968 and BS 2456.NOTE 1.The nominal sizes correspond with the pipe size of the thread on the inlet shank as specified in BS 2779.The nominal sizes 3/x and 1/4 are formed by making special inlets on the sizes and 1/z respectively.Nominal sizes 3/a and/2 are made in body form pattern I or 0.NOTE 2.The titles of the publications referred to in this standard are listed on the inside back cover.2 Definition For the purposes of this Part of BS 1212 the following definition applies.piston type float operated valve.A non-equilibrium float operated valve in which the flow of water is controlled by the horizontal movement of a piston.3 Designation for ordering Piston type float operated valves shall be designated by the following:(a)the nominal size;(b)the words piston type float operated valve;(c)the seat number and the body with which it can be used;(d)the number of this British Standard in the form BS 1212/1;(e)bottom entry connection,if required.Example.Nominal size /z piston type float operated valve,no.6 seat,body II,BS 1212/1.4 Marking 4.1 General A piston type float operated valve shall be permanently and legibly marked in accordance with 4.2 and 4.3 in such a way as not to deform any working part.4.2 On the body Rolled,cast or stamped on the body shall be the following:(a)the number of this British Standard in the form(b)the manufacturers name or trademark.BS 1212/1*;4.3 On every seat including spares The flange of the seat shall be marked with the following:(a)the manufacturers name or trademark;(b)the body(or bodies)with which it can be used(I to VI);(c)the designation of the seat(3,5,6,9,13,16,19,24,25 or 32).In the case of plastics seats,the marking shall be either within the recess for embossed marking or on the flat face for engraved marking(see figure 9).Marking BS 1212/1 on or in relation to a product represents a manufacturers 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 therefore solely the responsibility of the person making the claim.Such a declaration is not to be confused with third party certification of conformity,which may also be desirable.2 Licensed copy:PONTYPRIDD COLLEGE,13/02/2008,Uncontrolled Copy,BSIw w w.b z f x w.c o mBS 1212:Part 1:1990 Specification.Section two Section two.Materials 5 Quality and finish 5.1 General The materials to be used in the construction of components for piston type float operated valves shall be chosen from those given in table 1.5.2 Effect of non-metallic materials on water quality When used under the conditions for which they are designed,non-metallic materials in contact with or likely to come into contact with potable water shall comply with BS 6920:Part 1.6 Plastics 6.1 With the exception of seats,where no reworked material shall be used(see 6.2),the plastics parts of piston type float operated valves shall be manufactured from the materials given in table 1 with,if required,the addition of not more than 15%of the manufacturers own clean reworked material complying with this Part of BS 1212.No other reworked material shall be used.6.2 Seats from plastics shall be manufactured from new nylon,acetal polymer or polypropylene copolymer of a hardness not less than D75(Shore)when measured in accordance with BS 2782:Part 3:Method 365B.7 Castings Cast components shall be sound and shall comply with BS 6615.8 Hot stampings Hot stamped components shall be sound and shall comply with BS 3885.9 Mouldings Mouldings shall be sound and free from flash.10 Machining All machining shall be carried out so that parts comply with the dimensions specified in this Part of BS 1212 and are correctly aligned when assembled.All machined surfaces shall be free from burrs.3 Licensed copy:PONTYPRIDD COLLEGE,13/02/2008,Uncontrolled Copy,BSIw w w.b z f x w.c o mBS 1212:Part 1:1990 Specification.Section two X X 1 0,m xm x X X X X X X X X X xxx xxx xxx xxx 1 5 v)L-am.N 5 L o l n o 6 m U m U m F m z s U m-(v(D 0 U m 0 3 U m n.m c.?!E c.c(U c 0 0 0)a n 0 U w z c L 6-4 Licensed copy:PONTYPRIDD COLLEGE,13/02/2008,Uncontrolled Copy,BSIw w w.b z f x w.c o mBS 1212:Part 1:1990 Specification.Section three Nominal size of valve Section three.Design,construction and dimensions Body pattern 11 General A piston t.ype float operated valve shall have a general arrangement as shown in figure 1 and shall have dimensions complying with clauses 12 to 23 with a working tolerance of f 0.3 mm,unless otherwise specified in this Part of BS 1212.In nominal size 1/2 valves of body patterns I and II,the total projection from the face of the fixed backnut(which abuts on the inside face of the cistern shell)to the face of the body cap shall be a maximum of 75 mm to a /2 3/4 enable the valves to be fitted into cast-iron well bottom flushing cisterns.The combination of body pattern,seat number and size of float to suit the required pressure zone shall be as given in table 2.I I II II I I II II Ill Ill Ill 12 Screw threads Unless otherwise specified in this Part of BS 1212,screw threads shall comply with the free fit or normal class requirements of the relevant British Standard Table 2.Body,seat and float combination Nominal diameter of suitable standard float I Seat number Lever end screwing size,BSW For high pressure up t o 14 bar For medium pressure up to 7 bar For low pressure up t o 3 bar Copper BS 1968 Plastics BS 2456 Copper BS 1968 Plastics BS 2456 Copper BS 1968 Plastics BS 2456 in 5 6 6 7 mm 114 127 152-in 4/2 5 6 4/2 mm 102 114 114 127 in 4/2 4/2 4/z 5 mm 102 102 102 114 Y1 6 116 114 127 152-4/*4/2 5 6 102 114 114 127 4/2 4/2 4/2 5 102 102 102 114 152-5 6 7(8)127 152-4/2 5 6 102 114 152 6 9 13 6 7-7 8(9)9 Il6 6 8 8 152-5 6 7 114 152-9 13 16 8 8 19 24 10(11)-9(10)10(11)19 24 10(11)-9(10)10(11)8 8 25 32 11 12 10 10 8 2 I VI 12-I NOTE 1.The sizes given in this table are suitable for spherical floats complving with BS 2456 or BS 1968,except that where a second size is shown in parentheses such size should be used for brazed or bronze welded floats.NOTE 2.Non-spherical floats should have a lifting effort(calculated as required by BS 1968 or BS 2456)not less than that of the spherical float.NOTE 3.Size 3/8 and size 1/4 are identical to the size/2 and size 1/2 respectively,with the exception of the inlet shanks and backnuts.1 bar=10 N/m2=100 kPa.5 Licensed copy:PONTYPRIDD COLLEGE,13/02/2008,Uncontrolled Copy,BSIw w w.b z f x w.c o mBS 1212:Part 1:1990 Specification.Section three 13 Inlet connection 13.1 General Every inlet shank shall be screwed externally with parallel fastening thread that complies with class B of BS 2779 and is of the same nominal size as the valve(see figure 2 and table 3).13.2 Side entry valves For side entry valves,the inlet shank shall have dimensions as given in figure 2(a)and table 3.13.3 Bottom entry valves(size For bottom entry valves,an integral flange shall be provided on the inlet shank with dimensions as given in figure 2(b).only)13.4 Connection to 12 mm and 15 mm copper tube When the ends of the sizes 3/8 and inlet shanks are required to have dimensions suitable for connecting respec-tively to size 12 mm and 15 mm copper tube the inlet details shall be as given in figure 2(c)and table 3.13.5 Inlet elbow and inlet adaptor for bottom entry valves(size only)Inlet elbows and the inlet adaptor for bottom entry valves shall have dimensions as given in figure 3.Connection to the float valve shall be by the bottom inlet elbow shown in figure 3(a)or by the alternative inlet elbow end,joint ring and adaptor shown in figure 3(b).NOTE.Provision for tightening may be made in the bore of the inlet adaptor provided the flow through the seat is not reduced.Connection between the bottom inlet shank and the inlet elbow shall be by means of suitably formed copper tube with dimensions and working pressures as given in table X or table Y of BS 2871:Part 1:1971,the seal being made by a capillary or compression joint complying with BS 864:Part 2 or by any method such that the seal complies with clause 24.Each bottom entry valve assembly shall be provided with an adjustable lockable stay at its upper end to act as a stop against the cistern wall.14 Backnuts 14.1 General Backnuts shall be of the following types(see figure 4 and tables 4 to 6).Type(a).With an integral flange used for securing the inlet shank to the cistern when tightened against the outside wall of the cistern.Type(h).A spigoted backnut for size piston type float operated valves for use in flushing cisterns comply-ing with BS 1125,in which the hole is larger than is required for the inlet shank in order to provide an alternative overflow position.Type(c).A fixed flange backnut,which acts as a flange on the inner face of the cistern shell.There shall be means for tightening the nuts,e.g.hexagons.Plastics backnuts shall comply with clause 25.14.2 Backnuts for side entry cisterns Inlet shanks shall be provided with two backnuts.For nominal size following combinations of backnuts shall be supplied:float operated valves,one of the type(a)and type(b);type(b)and type(cl;type(b)and type(b).For other sizes,type(a)and type(c)shall be supplied.14.3 Backnuts for bottom entry cisterns Inlet shanks shall be fitted with a type(a)or type(b)backnut.15 Bodies Bodies shall have dimensions as given in table 7.The form of the outlet shall be as shown in figure 5.There shall be no features that facilitate the subsequent fitting of a silencing pipe.16 Body coupling nuts Body coupling nuts shall be of the types shown in figure 6 and shall have dimensions as given in table 8 and shall be free to revolve when the type(c)backnut(see figure 4(c)is screwed hard up to the end of the inlet shank