How to determine the quality of grey iron castings?

1. Appearance quality inspection Generally, casting manufacturers can inspect the quality of grey cast iron parts through surface observation. This includes using auxiliary tools to check the dimensions and weight deviations of the castings. For common surface casting defects such as pores, cracks, shrinkage, and deformation, visual inspection can be carried out.

2. Internal quality inspection The internal quality of grey cast iron parts mainly involves mechanical properties, chemical composition, and internal defects of the casting. To check mechanical properties, manufacturers need to test the tensile strength, elongation, and hardness of the casting; for chemical composition analysis, the main focus is on the proportion of five elements in the casting: carbon, phosphorus, manganese, silicon, and sulphur; for internal defects, non-destructive testing is mainly used, employing ultrasonic and radiographic methods to determine the exact location of internal defects, followed by repair of the casting.