重马力汽车水泵-节温器壳体一体铸造工艺设计

Integrated casting process for heavy horsepower automobile pump and the thermostat shell

针对水泵-节温器壳体一体铸造中出现的铸件砂眼、浆眼及冲刷缺陷等问题,设计了整套铸造工艺及其模具。首先利用3D建模技术,构建了一体铸件的进水口、出水口、节温器和涡流室结构模型,分析了影响铸造质量的关键因素,确定了初始铸件分形工艺、收缩率和加工余量,初步设计了一体化壳体浇注系统;然后采用Magma软件,对设计的壳体、流体模具、铸造工艺软程进行了分析验证,根据分析结果改进了浇注模具和铸造工艺规程。研究结果表明:改进后的铸件温度分布均匀,无过冷温度区,铸件存在冷隔气孔等缺陷风险小,充型良好,铸件收缩过程无明显孤立液相区,也无明显高温热节区。

Aiming at the problems of casting sand holes,the slurry eyes and scour defects in the integral casting of the water pump-thermostat housing,the whole set of casting processes and moulds were designed innovatively.Firstly,3D modeling technology was used to build the structural models of water inlet,water outlet,thermostats and vortex chambe which analyzed the key factor affecting casting quality,determined the fractal process,shrinkage and machining allowance of castings,and preliminary designed an integrated shell casting systems as well.Secondly,the Magma software was used to verify the designed housing,casting moulds,and casting procedure.According to the analysis results,the pouring mould and casting process rules were improved.The results indicate that the temperature of the improved castings is uniform,which has advantages such as no subcooling temperature zone,little risk of defects of cold barrier blowhole,good filling,no isolated liquid zones in the shrinkage processes and obvious hot spot at high temperature places.