1、BRITISH STANDARD BS 1212-2: 1990 Float operated valves Part 2: Specification for diaphragm type floatoperated valves (copper alloy body) (excluding floats) UDC 621.646.618:621.646.38BS1212-2:1990 This British Standard, having been prepared under the directionof the Building ServicesStandards Committ
2、ee, was published under the authorityof the Board of BSI andcomes into effect on 29 June 1990 BSI 01-2000 First published September 1970 First revision June 1990 The following BSI references relate to the work on this standard: Committee reference SEB/2 Draft for comment 83/11865 DC ISBN 0 580 15846
3、 2 Committees responsible for this BritishStandard The preparation of this British Standard was entrusted by the Building Services Standards Committee (SEB/-) to Technical Committee SEB/2 upon which the following bodies were represented: Association of Manufacturers of Domestic Electrical Appliances
4、 Association of Manufacturers of Domestic Unvented Supply Systems Equipment (MODUSSE) Association of Water Officers Ltd. British Bath Manufacturers Association British Gas Corporation British Non-ferrous Metals Federation British Plastics Federation British Valve Manufacturers Association Ltd. Build
5、ers Merchants Federation Consumer Standards Advisory Committee of BSI Copper Tube Fittings Manufacturers Association Council of British Ceramic Sanitaryware Manufacturers Department of the Environment (Building Research Establishment) Department of the Environment (Property Services Agency) Departme
6、nt of the Environment (Water Directorate) Department of Trade and Industry (National Weights and Measures Laboratory) Institute of Clerks of Works of Great Britain Inc. Institute of Plumbing Institution of Gas Engineers Institution of Public Health Engineers Institution of Water Engineers and Scient
7、ists Metal Sink Manufacturers Association National Association of Plumbing, Heating and Mechanical Services Contractors National Brassfoundry Association Royal Institute of British Architects Society of British Gas Industries South London Consortium Water Authorities Association Water Companies Asso
8、ciation Amendments issued since publication Amd. No. Date of issue CommentsBS1212-2:1990 BSI 01-2000 i Contents Page Committees responsible Inside front cover Foreword iii Section 1. General 1 Scope 1 2 Definition 1 3 Designation for ordering 1 4 Marking 1 Section 2. Materials 5 Quality and finish 2
9、 6 Plastics 2 7 Castings 2 8 Hot stampings 2 9 Mouldings 2 10 Machining 2 Section 3. Design, construction and dimensions 11 General 4 12 Screw threads 4 13 Inlet connection 4 14 Backnuts 4 15 Bodies 4 16 Body coupling nuts 4 17 Backplate nuts 4 18 Backplates 5 19 Backplate plungers 5 20 Seats 5 21 D
10、iaphragms 5 22 Levers 5 23 Float adjusters and thumb screws 5 24 Split cotter pins 5 25 Discharge arrangement 5 Section 4. Performance 26 Hydraulic pressure and shut-off 6 27 Backnut distortion 6 28 Backflow prevention 6 29 Flow 6 30 Hydraulic pressure on discharge arrangement 6 Appendix A Method of
11、 test for shut-off when assembled with appropriate float 17 Appendix B Method of test for distortion of size “ plastics backnuts 17 Appendix C Method of test for backflow prevention 17 Appendix D Method of test for flow 18 Appendix E Method of test for effect of hydraulic pressure on discharge arran
12、gement 18 Figure 1 Section of typical size diaphragm type float operated valve 6 Figure 2 Inlet shanks 8 Figure 3 Inlet elbows 9 Figure 4 Backnuts 10BS1212-2:1990 ii BSI 01-2000 Page Figure 5 Body 11 Figure 6 Body coupling nuts 12 Figure 7 Backplate nuts 12 Figure 8 Backplate 13 Figure 9 Backplate p
13、lunger 13 Figure 10 Seats and joint ring for seats 14 Figure 11 Diaphragm 15 Figure 12 Lever 16 Figure 13 Float adjuster and thumb screw 16 Figure 14 Typical arrangement of apparatus for backflow prevention test 19 Figure 15 Typical arrangement of apparatus for flow test 19 Table 1 Materials 3 Table
14、 2 Seats 15 Table 3 Seat and float combination 17 Publications referred to Inside back coverBS1212-2:1990 BSI 01-2000 iii Foreword This Part of BS1212 has been prepared under the direction of the Building Services Standards Committee and specifies requirements for diaphragm type float operated valve
15、s (excluding floats). It supersedes BS1212-2:1970, which is withdrawn. The new features in this Part of BS1212 include the following: a) the possible production of certain components from plastics materials; b) a seat numbering system; c) a bottom entry inlet connection and its associated inlet elbo
16、w, with adjustable stay; d) a recognition of the greater lifting effort of plastics floats over copper floats of equivalent size; e) a test for plastics backnut strength, in line with BS1212-3; f) a recognition of current manufacturing practice by deletion of reference to the use of agate tipped sea
17、ts; g) a recognition of methods of attachment of the discharge arrangements currently used in float valves manufactured in accordance with BS1212-3, and a test to verify their effectiveness; h) a modification of the method of dimensioning some components to ensure the lever does not rise above the h
18、orizontal at valve closure; j) the dimensional alignment of the body inlet connection with BS1212-1, which now requires only one seat joint ring for either plastics or metal seats. Float operated valves complying with BS1212-2 and carrying the Kitemark are automatically eligible for listing in the W
19、ater Research Centre Fittings Scheme Directory of Water Fittings. This Part of BS1212 has been revised in metric terms, except for certain thread sizes and pipe thread designations which are retained in imperial sizes to accord with BS2779. A British Standard does not purport to include all the nece
20、ssary 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 pages This document comprises a front cover, an inside front cover, pages i to iv, pages1
21、to 20, 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.iv blankBS1212-2:1990 BSI 01-2000 1 Section 1. General 1 Scope This Part of BS1212 speci
22、fies materials, dimensions, tolerances and performance requirements for diaphragm type float operated valves (copper alloy body) of nominal sizes ) and “ with seat numbers 3, 5, 6 and 9 intended for use with floats complying with BS1968 and BS2456. NOTE 1The nominal sizes correspond with the pipe si
23、ze of the thread on the inlet shank as specified in BS2779. The nominal size ) is formed by making a special inlet on the size “. NOTE 2The 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
24、 definition applies. diaphragm type float operated valve a float operated valve in which the flow of water is controlled by the flexing of a diaphragm and which incorporates or is fitted with a discharge arrangement to conduct water into the cistern to which the float operated valve is to be fitted
25、NOTEIn operation, flow from the valve reduces as the water level rises towards shut-off water level. The change in water level over which the flow progressively reduces from maximum to zero is at least four times the nominal size of the valve. 3 Designation for ordering Diaphragm type float operated
26、 valves shall be designated by the following: a) the nominal size; b) the words “diaphragm type float operated valve”; c) the seat number; d) the number of this British Standard in the form of BS1212-2; e) bottom entry connection, if required. Example. “Nominal size diaphragm type float operated val
27、ve, no. 6 seat, BS1212-2”. 4 Marking 4.1 General A diaphragm type float operated valve shall be permanently and legibly marked in accordance with4.2 and 4.3 in such a way as not to deform anyworking part. 4.2 On the body Rolled, cast or stamped on the body, backplate or backplate coupling nut shall
28、be the following: a) the number of this British Standard in the form BS1212-2 1) ; b) the manufacturers name or trade mark. 4.3 On every seat including spares The flange of the seat shall be marked with the following: a) the manufacturers name or trade mark; b) the designation of the seat (3, 5, 6 o
29、r 9) (see20.2). 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 clause 20 and Figure 10). 1) MarkingBS1212-2 on or in relation to a product represents a manufacturers declaration of conformity, i.e. a cla
30、im 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 de
31、sirable.BS1212-2:1990 2 BSI 01-2000 Section 2. Materials 5 Quality and finish 5.1 General The materials to be used in the construction of components for diaphragm 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 u
32、nder 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 BS6920-1. 6 Plastics 6.1 With the exception of seats, backplates and backplate plungers, where no reworked material shall be used (see 6.2 and 6
33、.3), the plastics parts of diaphragm 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 BS1212. No other reworked material shall be used
34、. 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 BS2782-3:Method 365B. 6.3 Backplates and backplate plungers from plastics shall be manufactured from new acetal polymer w
35、ith a hardness not less than D80 (Shore) whenmeasured in accordance with BS2782-3:Method 365B. 7 Castings Cast components shall be sound and shall comply with BS6615. 8 Hot stampings Hot stamped components shall be sound and shall comply with BS3885. 9 Mouldings Mouldings shall be sound and free fro
36、m flash. 10 Machining All machining shall be carried out so that parts comply with the dimensions specified in this Part of BS1212 and are correctly aligned when assembled. All machined surfaces shall be free from burrs.BS 1212-2:1990 BSI 01-2000 3 Table 1 Materials Material/material specification C
37、omponent Castings Rod for hot pressings, forging and machining Stainless steel Rubbers Fibres Plastics BS 1400 SCB1 or SCB3 (seenote 1) BS 1400 DCB3 BS 1400 PCB1 BS 1400 LG1 or LG2 BS 2872 CZ122 BS 2872 CZ129 BS 2874 CZ121 BS 2874 CZ132 BS 2874 PB102 BS 1400 G1 BS 970-1 304515 Synthetics of 60 to 70
38、 IRHD (see BS 903-A26) BS 3964 or BS 5292 Acetal polymer Nylon Polypropyfen e copolymer Body X X X X X X X Backplate X X X X X X X Backplate nut X X X X X X X Diaphragm X Lever X X X X X X X X Backplate plunger (see note 2) X X X X X X X X See6.3 Float adjuster X X X X X X X X X Thumb screw X X X X
39、X X X X Seat X X X X See 6.2 X Joint ring Inlet shank to seat X X X X X Inlet adaptor to inlet elbow X X X X X Inlet shank X X X X X X X Body coupling nut X X X X X X X Integral flange backnut type(a) size “ X X X X X X X X X size ) X X X X X X X Spigoted backnut type (b) size “ X X X X X X X X X si
40、ze ) X X X X X X X Fixed flange backnut type (c) size “ X X X X X X X X X size ) X X X X X X X Inlet elbow X X X X X X X Inlet adaptor X X X X X X X Split cotter pin See clause 24 Discharge arrangement See 25.6 NOTE 1Copper content may be reduced to 62% for SCB1 and SCB3. NOTE 2Brass backplate plung
41、ers may be electroplated with nickel or tin.BS1212-2:1990 4 BSI 01-2000 Section 3. Design, construction and dimensions 11 General A diaphragm type float operated valve shall have a general arrangement as shown in Figure 1 and shall have dimensions complying with clauses 12 to 25 with a working toler
42、ance of 0.3mm unless specified in this Part of BS1212. 12 Screw threads Unless otherwise specified in this Part of BS1212, screw threads shall comply with the free fit or normal class requirements of the relevant British Standard. 13 Inlet connection 13.1 General Every inlet shank shall be screwed e
43、xternally with parallel fastening thread that complies with class B of BS2779 and is of the same nominal size as the valve (see Figure 2). 13.2 Side entry valves For side entry valves, the inlet shank shall have dimensions as given in Figure 2(a). 13.3 Bottom entry valves (size “ only) For bottom en
44、try valves, an integral flange shall be provided on the inlet shank with dimensions as given in Figure 2(b), and shall be supplied with a sealing washer to facilitate connection of the cistern. 13.4 Connection to 12mm and 15mm copper tube When the end of the inlet shank is required to have dimension
45、s suitable for connecting to 12mm and15mm copper tube, the inlet details shall be as given in Figure 2(c). 13.5 Inlet elbow and inlet adaptor for bottom entry valves (size only) Inlet elbows and inlet adaptors shall have dimensions as given in Figure 3. Connection to the float valve shall be by the
46、bottom inlet elbow shown in Figure 3(a) or by the alternative inlet elbow end, joint ring and adaptor shown in Figure 3(b). NOTEProvision 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 i
47、nlet elbow shall be by means of suitably formed copper tube complying with Table X or Table Y of BS2871-1:1971, the seal being made by a capillary or compression joint complying with BS864-2 or by any method such that the seal complies with clause26. Each bottom entry valve assembly shall be provide
48、d 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). Type (a). With an integral flange used for securing the inlet shank to the cistern when tightened against the outside wall
49、of the cistern. Type (b). A spigoted backnut for size “ diaphragm type float operated valves for use in flushing cisterns complying with BS1125, 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 27. 14.2 Backnuts for side entry cisterns Inlet shanks shall b
