Casting: There are iron castings and steel castings. First, make a wooden mold according to the size of the casting, which is generally larger than the actual size. On the one hand, molten iron or steel will shrink after cooling; On the other hand, there should be room for processing. The second step is to turn over the sand, that is, to wrap the wooden mold with sand and make it into a "reverse mold" sand mold; After that, the sand mold will dry (if there is water in it, it will explode! ), casting and molding. Under normal circumstances, castings should be left in the natural state for a long time (exposed to wind, sun and rain) to eliminate their internal stress. If they are to be processed immediately, they need annealing (heat treatment). Main equipment: heating furnace, sand mold machine, centrifugal casting machine, etc.

Forging: heating the blank to a proper temperature, extruding and forging to eliminate uneven internal stress, internal defects and shapes. Main equipment; Heating furnace, hydraulic press, forging hammer, etc.

Welding: welding all parts into an assembly. Carbon steel parts are mainly welded by electric welding machine, alloy parts and stainless steel parts are welded by argon arc welding machine, and non-ferrous metal parts such as copper, aluminum and silver are welded by gas welding machine. Main equipment: general electric welding machine, argon arc welding machine, gas welding machine and working platform.