大型水电机转轮铸件充型过程仿真及浇注系统优化

Simulation of Filling Process and Optimization of Pouring System for Hydroelectric Turbine Runner Castings

采用侧接浇道和底注式方案,借助ProCAST软件对1000 MW级特大型水电机转轮下环的充型过程进行了模拟分析,结果表明两种生产方案都有充型不均匀现象,判断充型不均匀的主要原因是直浇道和横浇道的非均匀排布。后续通过优化底注式浇注系统结构,有效改善了铸件的充型不均匀性,但仍存在冷隔乃至内浇道关闭问题;通过砂型预热、改变浇道数量和尺寸等措施进一步优化,解决了内浇道关闭问题,有效实现了铸件平稳快速均匀充型,达到预想的浇注效果。

The simulation analysis of the filling process of the lower ring for the 1000MW class extra-large hydroelectric runner was carried out by using ProCAST software with the side-joined gate and the bottom-injection scheme,and the results showed that both production schemes had uneven filling phenomenon.It is assumed that the main reason for the uneven filling is the non-uniform arrangement of the straight and cross pouring sprues.Subsequently,by optimizing the structure of the bottom injection pouring system,the filling unevenness of the casting was effectively improved,but there were still problems of cold separation and even gate closure.Further optimization by means of sand box preheating,changing the number and size of sprue,solving the gate closing problem,effectively achieving smooth and fast uniform filling of castings and reaching the desired pouring effect.