大型不锈钢阀门精铸工艺的探讨

Production of Large Stainless Steel Valve in Investment Casting

特大型不锈钢阀体熔模精密铸造与砂型铸造比较,最大的问题是铸件的凝固控制。通过对型壳的组成和厚度的处理,冒口补缩系统的改进和浇注工艺的控制等措施,降低钢水的浇注温度,增加补浇次数,加盖覆盖剂等,避免了缩孔和缩松现象,组装后试验完全合格。

Compared with large stainless steel valve body in sand casting,it was difficult to control solidification process in investment casting,which results in some defects in the valve body.Through adjusting the composition and thickness of mold shell and improving the feeding system as well as controlling pouring process,the shrinkage porosity(hole)can be effectively eliminated in the valve body in investment casting,obtaining qualified valve body.