![]() It connects with the computer automatic controller. And the thermocouple should be fixed on the parts needed to PWHT through the compensating conductor. The caterpillar electric heater and linear electric heater should be fixed on the parts which are needed to PWHT they connect with the automatic controller through cable. But for the high carbon content and high stiffness of the welding parts, it is required to preheat and heat treatment, such as the wall thickness of 30mm carbon steel pipe. General carbon steel welding performance is good, the welding can be without preheated and heat treatment. PWHT is based on the hardness of the steel, the thickness of the welding parts, structural rigidity, welding methods and conditions of use. Welding process, because local overheating will cause the pipe deformation and shrinkage stress, so steel pipe return to heat treatment after welding to eliminate internal stress. Due to the steel pipe transporting gas or liquid need to bear a certain pressure, internal stress produced in the cold rolling process must be eliminated.
0 Comments
Leave a Reply. |