IS:8737

IS 8737 (governed by the Bureau of Indian Standards specification IS 8737: Valve Fittings for Use with Liquefied Petroleum Gas [LPG] Cylinders of More Than 5 Litre Water Capacity) defines the mandatory material, design, and testing criteria for high-pressure LPG cylinder valves. Commonly known in the brass extrusion and forging industry as IS 8737 Modified Forging Brass (or 8737 MOD), this alloy is engineered to prevent volatile fuel gas leakage under high cyclic working pressures. Formulated with 56.5% to 60.0% Copper, 1.0% to 2.0% Lead, and a mandatory minimum addition of 0.50% Manganese (Mn), this alloy provides high structural yield strength and impact toughness while retaining the plasticity required for hot closed-die forging and the machinability needed for precision gas-tight threading.