BS 1212-3:1990

Committees responsible
Foreword
Section 1. General
1 Scope
2 Definitions
3 Designation for ordering
4 Marking
Section 2. Materials
5 Effect of non-metallic materials on water quality
6 Plastics
7 Metals
Section 3. Design, construction and dimensions
8 Inlet connection
9 Seats
10 Backnuts
11 Float arm or float arm assembly
12 Discharge arrangement
Section 4. Performance
13 Distortion and deflection
14 Hydraulic pressure
15 Backflow prevention
16 Flow
17 Endurance
Appendix A - Distortion test for backnuts and inlet shank
Appendix B - Diaphragm type float operated valve assembly test
Appendix C - Float attachment thread distortion test
Appendix D - Shut-off pressure test
Appendix E - Method of test for effect of dynamic pressure
             on discharge arrangement
Appendix F - Backflow prevention test
Appendix G - Flow test
Appendix H - Endurance test
Publications referred to

Operational requirements.

This Part of BS 1212 specifies the performance requirements, materials, certain dimensions and tolerances of diaphragm type float operated valves (plastics bodied) of nominal size ½ for cold water services only, capable of accepting interchangeable low or high pressure renewable seats for use at pressure up to and including 3 bar¹⁾ and up to and including 14 bar respectively (see 9.1) and intended for use with 114 S or 114 NS floats (plastics) conforming to BS 2456.

NOTE 1 The nominal size is that corresponding with the Class G ½ B pipe thread specified in BS 2779.

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