Inspect the macroscopic defects exposed on the surface of the casting with the naked eye or with the aid of a low magnifying glass, and check whether the production marks of the casting are correct and complete.
When testing, it should be determined whether the casting is qualified for the test project, and distinguish qualified products, repaired products and waste products. The defects that can be detected by visual appearance inspection include flying wing, burr, lift shape, sand expansion, sand washing, sand removal, exudation, cold isolation, pouring break, surface cracks (including hot crack, cold crack and heat treatment crack), rat tail, groove, sand scarring, sand sticking, rough surface, wrinkled skin, shrinkage, failed to pour, not poured, running fire, mold leakage, mechanical damage, wrong shape, wrong core, off-core, casting Deformation warping, cold beans, and inclusion, porosity, shrinkage, slag porosity, slag shrinkage, sand holes exposed on the surface of the casting.
Before testing, the casting factory should formulate or agree with the user in advance the qualified product standards for the testing project. Visual appearance inspection is divided into two kinds: process inspection and terminal inspection. Process testing is generally carried out after sand drop or cleaning; Terminal inspection is carried out after cleaning or heat treatment and before castings are stored or delivered. Single or small batch production of castings should be tested all castings, batch or mass production of castings can be sampled by batch or periodic test sample castings.
