(1) Material and mechanical properties of precision casting parts:
The technological characteristics and mechanical properties of the parts roughly determine the type of the blank. For important steel parts, forgings should be selected to obtain good mechanical properties; when the shape is simple, steel castings should be used. The material is complex and the mechanical properties are not required. It can be used as the common profiles or billets of non-ferrous metal parts.
(2) The structural shape and size of the parts:
The blanks of large and simple parts are mostly made by sand casting or free forging, and the blanks of complex structures are mostly made by casting. The blanks of small parts can be made by die forging or pressure. The blanks of steel parts are mainly used for forging. If the diameter of step is not very large, it can be used for bar. If the size of each step is very different, the forging should be used.
(3) Existing production conditions:
In determining the billet, the specific production conditions must be combined.
(4) Make full use of new technologies and materials:
In order to save material and energy and improve the efficiency of mechanical processing, casting methods and materials such as precision casting, precision forging, cold rolling, cold extrusion, powder metallurgy, profiled steel and engineering plastics should be fully considered. In this way, the amount of mechanical processing can be greatly reduced, even without processing, and the economic benefits will be very significant.