This standard establishes the specifications for copper alloy decorative single taps, combination tap sets, and stop valves intended for water service applications. It details the requirements concerning design, materials, dimensions, workmanship, and performance evaluations such as watertightness, mechanical durability, and hydraulic flow characteristics. The code is essential for manufacturers, testing personnel, and engineers managing production and installation of sanitary fittings in residential and municipal water supply systems.
Overview
This standard establishes the specifications for copper alloy decorative single taps, combination tap sets, and stop valves intended for water service applications. It details the requirements concerning design, materials, dimensions, workmanship, and performance evaluations such as watertightness, mechanical durability, and hydraulic flow characteristics. The code is essential for manufacturers, testing personnel, and engineers managing production and installation of sanitary fittings in residential and municipal water supply systems.
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Frequently Asked
This standard designates specific copper alloy materials for various tap and valve components. Key materials include cast brass (Grade CB 2 as per IS 292:1983), die-cast brass (Grade DCB2 under IS 1264:1989), forged brass (Grade FIB per IS 6912:1985), leaded tin bronze (Grade LTB 2 according to IS 318:1981), brass rods (Type 1 Half hard as per IS 319:1989), brass tubes (IS 407:1981), and soft annealed copper tubes (IS 10773:1983). Flanges and other parts also follow similar material specifications for durability and compliance.
Watertightness is confirmed through laboratory air pressure testing. The procedure involves immersing the tap or valve in water and applying air pressure of 0.2 MPa for 20 seconds with the outlet closed. For spindles sealed with O-rings, the pressure is gradually reduced to 0.02 MPa for an additional 20 seconds. Manually operated diverter valves are tested at 0.6 MPa air pressure with the outlet open and seat closed with specified torque. Passing the test requires no observable air leakage or bubbles during the test duration.
Combination tap assemblies have defined dimensions based on mounting type. For wall mounting, inlet shank threads should be G 1/2 B with minimum shank length of 25 mm and inlet centre spacing of 148 mm. Pillar mounting assemblies have specified dimensions for base-to-centre distances (21–31 mm), shank diameter (max 29 mm), flange sizes (minimum 42 mm), and tube outer diameter (minimum 9.5 mm with 0.6 mm thickness). These dimensions ensure compatibility and proper fitting according to the standard.
All significant surfaces of taps, combination assemblies, and stop valves must receive nickel-chromium plating to ensure corrosion resistance and aesthetic quality. Exceptions include concealed stop valve bodies and side stop valves on pillar-mounted taps which may have a polished bright or uncoated cast finish. Plastic knobs may be either as-moulded or nickel-chromium plated as per IS 8376:1988, while zinc alloy knobs require nickel-chromium plating conforming to IS 4828:1983.
Mechanical strength testing entails removing the bonnet assembly and sealing the bonnet end and outlet with plugs. The valve body is then subjected to a static water pressure of 2.5 MPa for 60 seconds at the connection point with the pipe. The valve passes the test if no deformation or leakage occurs during or after the procedure, thus verifying its ability to withstand operational stresses without failure.
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