1. Surface cleaning
Shot blasting equipment is first applied to the removal of sand and scale on the surface of cast steel and cast iron.
Almost all steel castings, gray castings, malleable steel pieces, nodular iron pieces must be shot blasting.This is not only to remove the scale and sand on the surface of the casting, but also an indispensable preparation procedure before the casting quality inspection. For example, the shell of large gas turbine must be cleaned strictly before the non-destructive inspection to ensure the reliability of the inspection result.In general casting production, shot blasting and peening is an essential process for finding surface defects such as subcutaneous pores, slag holes, sand sticking, cold separation and peeling.
The surface cleaning of non-ferrous metal castings, such as aluminum alloy and copper alloy, is not only to remove the scale and find the surface defects of the casting, but also to remove the burr of the die casting by blasting shot peening and to obtain the surface quality with decoration significance.In metallurgical iron and steel production, blast peening or pickling is a combined mechanical or chemical process used to remove phosphorous coating to ensure high productivity in mass production of iron and steel.In the production of silicon steel sheet, stainless steel sheet and other alloy steel plate and strip, shot blasting or pickling must be carried out after annealing in the cold rolling process to ensure the surface roughness and thickness accuracy of the cold rolled steel plate.
2. Workpiece strengthening
According to the theory of metal strength, the main direction to improve the metal strength is to increase the dislocation density inside the metal.It is proved that shot blasting is an effective method to increase the structure of metal dislocation.This is of great significance to some metal that cannot be hardened by phase change hardening (such as martensite hardening) or to the workpiece that needs further strengthening based on the realization of phase change hardening.Aviation, aerospace industry, automobile, tractor and other parts and components need to be light, but the reliability requirements are getting higher and higher.
1. Surface cleaning