BS 1212-2:1990

Committees responsible
Foreword
Section 1. General
1 Scope
2 Definition
3 Designation for ordering
4 Marking
Section 2. Materials
5 Quality and finish
6 Plastics
7 Castings
8 Hot stampings
9 Mouldings
10 Machining
Section 3. Design, construction and dimensions
11 General
12 Screw threads
13 Inlet connection
14 Backnuts
15 Bodies
16 Body coupling nuts
17 Backplate nuts
18 Backplates
19 Backplate plungers
20 Seats
21 Diaphragms
22 Levers
23 Float adjusters and thumb screws
24 Split cotter pins
25 Discharge arrangement
Section 4. Performance
26 Hydraulic pressure and shut-off
27 Backnut distortion
28 Backflow prevention
29 Flow
30 Hydraulic pressure on discharge arrangement
Appendix A - Method of test for shut-off when assembled with
             appropriate float
Appendix B - Method of test for distortion of size [1/2] plastics
             backnuts
Appendix C - Method of test for backflow prevention
Appendix D - Method of test for flow
Appendix E - Method of test for effect of hydraulic pressure on
             discharge arrangement
Publications referred to

Specifies workmanship, dimensions and performance requirements for diaphragm type valves of nominal size 3/8 and 1/2, intended for use with floats complying with the requirements of BS 1968 and BS 2456.

This Part of BS 1212 specifies materials, dimensions, tolerances and performance requirements for diaphragm type float operated valves (copper alloy body) of nominal sizes ⅜ and ½ with seat numbers 3, 5, 6 and 9 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 size ⅜ is formed by making a special inlet on the size ½.

NOTE 2 The titles of the publications referred to in this standard are listed on the inside back cover.