Monel alloy forgings are basically made of castings skinning and forged into bars after heating. There is a large tendency of cracks in hot forging. After cold forging, medium temperature aging is generally adopted, and less forging ratio can solve the tendency of hot cracking. The welding of Monel alloy castings, when the carbon content and silicon content is increased, the welding performance is very poor, when the silicon content is more than 1.5%, it is not good repair welding, and all kinds of sulfur, phosphorus and low melting point metal will deteriorate the welding process of the alloy, so the general repair welding should be in low current, cold welding is appropriate.