480缸体漏箱的成因分析及防止措施

The Analysis and Prevention of the 480 Cylinder Block Leakage

介绍了采用冷芯盒制芯生产480缸体所产生的漏箱情况，分析认为漏箱产生的主要原因是浇注系统及模具设计不合理，熔炼温度及浇注温度偏高，砂箱紧固不良，通过对原工艺进行改进：采用中注、半开放式浇注系统，浇口比为E直：2F视：∑F内：1：1．7：1．1；熔炼温度控制在1520M530oC，浇注温度控制在1380～1420℃；设计套箱，将其套在组好的砂芯外面，再用榔头往下敲击套箱，靠套箱自身的斜度紧固。最终使480缸体的漏箱废品率由20．7％降到0．95％，全年预计可节约356万元。

The situation of cold box coremaking 480 cylinder block leakage was introduced. After analyzing,the main reason was believed as the unsuitability of gating system and mold design,high melting temperature and pouring temperature and poor sand box fastening. The improvements were focused on semi open middle gating system,gating ratios were ΣFpouring:ΣFrunner:ΣFflow=1:1.7:1.1. The melting temperature was between 1 520~1 530 ℃ and pouring temperature was between 1 380~1 420 ℃. A set of jackets was designed,and put on the sand cores. Then struck down the jackets with a hammer. The jackets was tightened by the impacts on slop. Finally,the waste rate on 480 cylinder block leakage was dropped from 20.7% to 0.95%. It was expected to save the cost by 3.56 million Yuan in a year.