基于计算机模拟的支架铸钢件铸造工艺设计及优化

目的对ZG270-500铸钢支架的铸造工艺进行优化设计,以达到工艺简单、成本低、操作简便、质量良好等要求。方法使用三维CAD软件和铸造模拟软件对相应铸造工艺方案进行了三维建模和铸造过程的模拟。针对工艺初始浇注系统设计了正放、倒放,底注式、阶梯式共4种不同组合的浇注方案。在对充型温度场进行模拟后,选择了倒放阶梯式与正放底注式浇注系统进行后续模拟。在对凝固进行模拟后,最终选择了正放底注式的方案并进行后续优化。在设计补缩系统时,通过多次调整冒口的位置与尺寸,以及冷铁的位置、尺寸与形状,达到工艺优化的效果。结果 4种初始方案中,倒放阶梯式浇注系统有利于顺序凝固,正放底注式浇注系统较为经济环保。凝固过程中,正放底注式浇注系统的疏松疏孔液相孤立区存在于铸件顶部,有利于补缩。初始补缩系统有效补缩了顶面两孔中心缺陷,优化后可使顶板和肋板的连接处,凝固最晚区域的缺陷大为改善。结论模拟表明,最终方案可基本消除铸件中的缺陷,保证铸件的质量与良好的工艺性。

Design and Optimization of Steel Casting Process for Bracket Based on Computer Simulation

This paper aims to optimize the casting process of ZG 270-500 cast steel bracket, to achieve the requirements of simple process, low cost, simple operation and good quality. Three-dimensional CAD software and casting simulation software were used to model and simulate the casting process. In this process, the initial pouring system was designed with four different pouring schemes: forward pouring, backward pouring, bottom pouring and step pouring. After simulation of mold filling tem-perature field, the inverted step casting system and the positive bottom casting system were selected for subsequent simulation. After simulation of solidification, the positive bottom injection scheme was finally selected and for further optimization. In design of the feeding system, the position and size of the risers, as well as the position, size and shape of the chills were adjusted for several times to achieve process optimization. In the four initial schemes, the inverted step casting system was beneficial to sequential solidification, while the forward bottom casting system was more economical and environmentally friendly. The results of solidification process show that the liquid phase isolated zone of porosity and shrinkage cavity existed at the casting top was beneficial to feed shrinkage. The initial feeding system can effectively feed the center defect of two holes on the top surface. After optimization, the defect in the joint of roof and boards and the area with the latest solidification was greatly improved. The simulation results show that the final scheme can basically eliminate defects in the casting and ensure casting quality and good manufacturability.