Train a lot of accessories are made by investment casting, such as engine parts, transmission parts, clutch, transmission, universal transmission device, main reducer, differential and half shaft), brake system parts, steering system accessories (booster assembly, steering knuckle ball head, steering knuckle, steering wheel, steering rod, booster pump, steering, steering machine, etc.), and many of them are carbon steel castings, high chromium steel castings, alloy steel castings, need strong mechanical properties, to ensure the safety of the train