The results showed that the production engineering matches the operating instructions, but the crack inside contains inlcusion and two sides exist the decarbonize phenomenon; The crack bitter end extends along the plain body in iron segregation band and the segregation band is inner to also exists inlcusion. 结果表明:生产工艺符合操作规程,但裂纹内部有夹杂物,两侧有脱碳现象,裂纹末端沿铁素体偏析带延伸,偏析带内部也存在夹杂物。