排气歧管铸件的铸造工艺设计与优化

Design and Optimization of Foundry Technology for Exhaust Manifold

针对排气歧管铸件孤立热节多,又无法设置冒口的情况,采用华铸工艺分析软件模拟铸件的凝固过程,预测缩孔、缩松缺陷出现的部位;采用铸件均衡凝固理论,设计浇注系统和冒口补缩系统,采用"宽、薄、短、斜"的冒口颈是充分利用石墨化膨胀自补缩作用的关键,采用该技术并优化相关工艺参数后,有效地克服了排气歧管铸件的缩孔、缩松缺陷,大幅度提高了铸件的工艺出品率和成品率,取得了显著的经济效益。

The exhaust manifold casting has many isolated hot-spots and it is impossible to set risers on it.To solve this problem,the Huazhu CAE software is applied to predict the position of shrinkage and dispersed shrinkage,and the proportional solidification technology is used to design the gating and feeding system.The riser neck must be ＇wide,thin,short and declining＇,which is the key technology to take full advantage of self-feeding by graphite self-expansion.After optimization of process parameters,the shrinkage defects of manifold were effectively eliminated,thereby the process yield was increased significantly and a significant economic benefit was obtained.