高密度造型型腔排气条件对灰铁件粘砂的影响

Influence of Cavity Exhaust Conditions on Gray Iron Adhering Sand in High Density Molding

本厂采用静压造型线生产的灰铸铁出口件制动轮毂、变速箱壳体、变矩器壳体等在生产过程中出现了严重的粘砂缺陷。通过控制浇注温度、浇注速度;调整型砂水分、挥发分、灼烧减量、透气性;提高砂型硬度;喷涂表面快干涂料等措施,均未解决产品表面严重粘砂缺陷。后经增加型腔排气针,手动打通型腔背部使其排气,产品粘砂缺陷得到有效解决。将该措施应用于其它粘砂产品,均取得良好效果。生产实践表明,高密度造型型腔排气条件对铸件粘砂缺陷有着重要影响。

The serious burn-on sand defect developed on the gray iron export castings made by the static pressure molding line such as brake hub,gearbox shell,torque converter shell,etc.ontrolling the pouring temperature,casting speed,the molding sand moisture,volatile component,loss on ignition（LOI）,permeability,the hardness of sand mold and painting the quick drying coating,the defect has failed be removed.After increasing the cavity exhaust needle,manually getting through the back of the cavity,the burn-on sand has been removed effectively.Other products have achieved good results.Production practice shows that the cavity exhausting condition has the important influence on the burn-on sand defect.