Analysis of solidification process and stress-strain of mud pump body in sand casting

The solidification process of sand casting mud pump body is accompanied by complex processes such as heat transfer, phase transformation, shrinkage and the interface between casting and mold. Many casting defects of sand casting mud pump body are produced in the solidification process, such as shrinkage porosity, shrinkage cavity and crack. Therefore, the control of solidification process of sand casting mud pump body is very important to eliminate sand casting defects It is very important to improve the performance of sand casting mud pump and improve the quality of sand casting mud pump. The traditional casting production cannot observe the solidification process in the process design stage. The designed process scheme can only be improved by detecting the quality of the sand casting mud pump body after pouring. The trial pouring process not only increases the development cost of the sand casting mud pump body, but also slows down the development cycle.

(1) Firstly, the theoretical basis of solidification process, stress and strain simulation is described, including solidification transfer

Mathematical model and algorithm used in thermal and stress field simulation, prediction of shrinkage porosity and shrinkage cavity.

(2) ProCAST is used to analyze the solidification process of casting mud pump body, including the temperature distribution of sand casting mud pump body and pouring riser, the change of solid phase rate in each part during solidification and the distribution of solidification time in each riser section. It is pointed out that the temperature distribution in each part of sand casting mud pump body is disordered and many isolated liquid phase areas are formed during solidification; The distribution of shrinkage porosity and shrinkage cavity defects is predicted, the causes of defects are analyzed, and the rationality of sand mold casting process scheme is judged.

(3) The stress field of the casting mud pump body is simulated by using the software ProCAST, the equivalent stress distribution, deformation distribution and thermal crack distribution of the mud pump body during solidification are analyzed, and the rationality of the structure and casting process scheme of the sand casting mud pump body are judged.

(4) The simulation results show that the castings produced by the designed casting process have shrinkage porosity, shrinkage cavity, deformation and other defects. In order to eliminate the casting defects and improve the casting quality, the process of sand casting mud pump needs to be improved.

In recent decades, due to the rapid development of computer hardware and software system, the numerical simulation of sand casting process of mud pump body has been studied a lot. Numerical simulation can effectively analyze various physical and chemical processes in the sand casting process of mud pump body, so that designers can deeply understand the details of fluid flow, heat transfer and solidification. The numerical simulation accurately calculates the changes of various fields (such as temperature field, flow field and stress field) in the sand mold casting solidification process of the mud pump body. The simulation results produce a large amount of data to characterize the transient flow characteristics (such as temperature and velocity) and the quality of the casting (such as shrinkage porosity and grain structure), So that researchers can observe and quantify those parameters that are not visible or measurable in the actual casting process, and comprehensively evaluate the casting process plan. The application of casting numerical simulation technology can accelerate the casting process design, optimize the casting process parameters, reduce the development cost of castings, improve the quality and process yield of sand casting of mud pump body, and realize green casting with low investment and low energy consumption.