厚大铸铁皮带轮缺陷的成因与控制措施

Analysis on Defects in Heavy Casting Iron Belt Pulley and Improvement of Technology

分析了厚大V型带轮缩孔缩松缺陷的形成原因及防止措施,V型带轮材质为HT250,壁较厚,采用树脂砂型铸造,通过合理控制浇注温度及速度,优化铸造工艺设计,严格控制化学成分,能够减轻甚至消除厚大轮式铸件在热节部位出现的缩孔缩松缺陷,使其完全满足性能要求,并为直径在800～1 500 mm间的中大型轮式铸件生产提供参考。

In this paper,the causes of shrinkage cavity and porosity of heavy casting iron belt pulley and the prevention measures are analyzed.The material of the casting is HT250,and it have thick wall.Through molding of resin-bonded sand,the process make full use of self feeding effect of graphitization expansion.It can reduce or even eliminate the shrinkage defects that appears in the hot spot of heavy wheel castings.The result show that it fulfill well meet the requirements of the performance,and it is available for 800~1500mm in diameter heavy wheel castings production.