Heat treatment of pneumatic ball valve after machining
1. The heat treatment after machining of pneumatic ball valves made of carbon steel, low alloy steel and ferritic steel shall be carried out according to regulations. The large elongation of pneumatic ball valves due to forming processing shall be determined according to the head with secondary curvature.
2. The cold formed austenitic stainless steel pneumatic ball valve must be subject to heat treatment except for one of the following cases:;
(1) . The thickness is not more than 10mm;
(2) When the * large elongation of cold working is not more than 5%, and the consensus among relevant units is that the depth of cold working or its influence is very small, so small that heat treatment is unnecessary.