A 26
CAP. 102]
Waterworks Regulations
[1989 Ed.
[Subsidiary]
15. Cast copper alloy fittings, for copper pipes screwed in accordance with Table 1 of BS 61, shall comply with the relevant requirements of BS 143 or 1256 for malleable cast iron and cast copper alloy pipe fittings.
16. Copper pipes to be jointed with compression fittings or capillary fittings or by bronze or autogenous welding shall comply with BS 2871, Part 1.
17. Capillary fittings or compression fittings shall comply with BS 864, Parts 2 and 3 for capillary and compression fittings of copper and copper alloy and compression fittings for pipes laid under the ground shall be Type B.
(L.N. 252 of 1977)
PART II
TAPS AND VALVES
1. Draw-off taps and stop valves of the ordinary screw-down pattern and of nominal size not exceeding 50 mm shall comply with BS 1010, Part 2 for draw-off taps and stop valves.
2. Draw-off taps and stop valves not being of the ordinary screw-down pattern, shall be capable of resisting a pressure of at least 2 000 kPa, and every valve, spindle, and other internal part and, where the nominal size of the tap or valve does not exceed 50 mm, the body thereof, shall be made of a corrosion resisting alloy.
3. Sluice valves of nominal size of 50 mm or more shall comply with BS 5163 for sluice valves for waterworks purposes of PN 10 or PN 16 according to the pressure to which the valve will be liable to be subjected under working conditions.
4. (1) Ball valves of the "Piston" type and of a nominal size not exceeding 50 mm shall comply with BS 1212, Part 1 for ball valves.
(2) Ball valves not being of the "Piston" type shall be sound and suitable and comply with the following requirements---
(a) high pressure valves shall close against a test pressure of 1 400 kPa, medium pressure valves against a test pressure of 700 kPa, low pressure valves against a test pressure of 300 kPa; and the valves, not being valves having an interchangeable orifice seating, shall have the letters "H.P.", "M.P." or "L.P." respectively cast or stamped on the body of the fitting, and shall, while held in a closed position, be capable of resisting a pressure of 2 000 kPa;
(b) valves of the piston type shall be provided with a washer of suitable vulcanized rubber or some other equally suitable material, and, for valves of nominal sizes not exceeding 50 mm the washer shall be enclosed in an internally flanged cap screwed to the piston;
(c) valves of nominal size not exceeding 50 mm, the body and the piston shall be of a corrosion-resisting alloy, the lever shall be of corrosion-resisting alloy or of copper and shall be of sufficient rigidity not to bend permanently under working conditions;
(d) valves of ferrous metal of a nominal size exceeding 50 mm shall be provided with a flange on their inlets complying with BS 4504, Part 1, Table 16, shall be protected against corrosion by dipping in accordance with the requirements of BS 4164 or by galvanizing in accordance with the requirements of BS 1387 and shall have all their working surfaces lined or faced with, and its orifice seating of, a corrosion-resisting alloy.
(3) Ball valve floats of a nominal outside diameter not exceeding 300 mm shall comply with BS 1968 for copper floats or with BS 2456 for plastic floats.
(4) Ball valves when fixed to a cistern shall have the size of the orifice, the size of the float and the length of the lever so proportioned to one another that, when the float is immersed to an extent not exceeding half its volume, the ball valves shall be watertight against the highest pressure at which it may be required to work.