How to ensure high-quality surface smoothness and dimensional accuracy of castings in the production process of Rail Transit Casting?

Ensuring high-quality surface finish and dimensional accuracy of the castings is crucial in the production process of Rail Transit Casting. This not only affects the aesthetics of the castings, but also directly impacts their performance and lifespan in rail transit equipment. To achieve this goal, we focus on the selection and pretreatment of raw materials. High quality raw materials are the foundation for producing high-quality castings. We carefully select casting alloys that meet standard requirements, and through refining and degassing treatment, reduce impurities and gas content in the alloy, thereby improving the intrinsic quality of the castings.
In terms of mold design and manufacturing, we adopt advanced CAD/CAM technology to achieve precise mold design and rapid processing. The surface smoothness and dimensional accuracy of the mold directly affect the forming quality of the casting. We strictly control the machining accuracy of the mold to ensure high surface smoothness and accurate dimensions.
In the production process, we adopt advanced casting techniques and equipment such as low-pressure casting, vacuum suction casting, etc. to reduce defects such as porosity and slag inclusion in castings, and improve the density and surface smoothness of castings. At the same time, we also pay attention to the control of pouring temperature and speed to ensure that the metal liquid flows evenly in the mold, avoiding defects such as cold insulation and shrinkage.
Finally, in the post-processing stage of the casting, we use processes such as sandblasting, grinding, and polishing to fine tune the surface of the casting, further improving its surface smoothness and aesthetics. At the same time, we also conduct strict dimensional inspection and quality control on the castings to ensure that the dimensional accuracy of the castings meets the design requirements.