1. Material and mechanical function requirements of parts
The process characteristics and mechanical properties of the part material roughly determine the type of blank. Steel parts are commonly used when the shape is simple and the mechanical function is not high. For important steel parts, for good mechanical function, forgings should be used, and when the complex mechanical function is not high, the steel parts are used; Common profiles or forged blanks for non-ferrous metal parts.
2. The structural shape and shape of the part
Large and simple structural parts are mostly sand forged or free forged; complex blanks are forged; small parts can be forged or pressure forged blanks; plate steel parts are used for forging blanks; shaft parts are blank, if step diameter The difference is not large, and the bar material can be used; if the difference of the step sizes is large, the forging piece should be selected.
3. The size of the production program
In a large number of large-scale production, a blank manufacturing method with high precision and high yield should be used. Castings are machined and precision forged using metal molds, and forgings or precision castings are used for forgings. The blanks are hand-made or free-forged in a single piece of small-scale production.
4. Existing production prerequisites
When determining the blank, it is necessary to combine the detailed production conditions, such as the actual level and capacity of the on-site blank manufacturing, the possibility of external cooperation, etc., otherwise it is not realistic.
5. Make full use of new processes and new materials
In order to save materials and energy, and improve the mechanical processing yield, full consideration should be given to the application of precision forging, precision forging, cold rolling, cold extrusion, powder metallurgy, special-shaped steel and engineering plastics in machinery, thus greatly reducing machining. Quantity, even without processing, the economic benefits are very obvious.