The commonly used method for macro inspection of sector gear die forgings is the low corrosion method and the fracture test of sulfur printing. The so-called low corrosion method is mainly used to verify the grain size and distribution of the crack distribution shape of the die forgings. However, the specifications of different materials used to show the low increase are different. There is also a fracture test method, which can be used to check the internal cracks and other defects that may exist in the die forgings, The inspection of steel die forgings is mainly used to verify the uniformity of large structural steel.

In addition to die forging stainless steel, the test piece is used for low level inspection without heat treatment, and other materials of die forging are usually treated before the low frequency spectrum of heating inspection. In addition to improving the quality of steel, a forging scheme is also proposed to reduce the resistance to flash flow and the deformation of final forging, and fully increase the initial forging temperature. In the process of die manufacturing, the surface finish of die cavity is ensured.