In the production process of heat-resistant castings, the quality of castings should be controlled and inspected. First of all, the process codes and technical conditions from raw materials and auxiliary materials to the control and inspection of each specific product should be formulated.Each process is strictly controlled and inspected in accordance with the process code and technical conditions.Finally, quality inspection of finished castings.To be equipped with reasonable testing methods and appropriate testing personnel.
The surface roughness of heat-resistant castings can be determined by comparing samples.The fine cracks on the surface can be examined by coloring method and magnetic powder method.The internal quality of the casting can be examined and determined by means of audio, ultrasonic, eddy current, X-ray and gamma rays.
The quality inspection results of heat-resistant castings are usually divided into three categories: qualified products, reworked products and rejected products.
1) qualified products refer to the castings whose external quality and internal quality meet the relevant standards or the technical conditions for delivery and acceptance;
2) repair products refer to the castings whose external quality and internal quality do not completely meet the standards and acceptance conditions, but are allowed to be repaired and can meet the requirements of the standards and technical conditions for casting delivery acceptance after repair;
3) waste product refers to the castings that are unqualified in both appearance quality and internal quality, and are not allowed to be repaired or fail to meet the standards and technical requirements for casting delivery acceptance after repair.Waste products can be divided into internal waste and external waste.Internal waste refers to waste castings found in foundries or foundry workshops;External waste refers to the waste product found after the casting is delivered, which causes much greater economic loss than internal waste.www.wuxiorient.com