In recent years, CAE technology has been widely used in the development and design of nodular cast iron products, analysis and manufacturing process. The filling and solidification process of nodular cast iron can be simulated on computer with the help of CAE software. The use of computer simulation technology in the process of nodular cast iron can shorten the trial production period of products, reduce production costs and improve material utilization.
As the key part of the hydraulic high-pressure cylinder, the nodular cast iron parts of the high-pressure cylinder end cover shall have sufficient strength and rigidity, compact organization, and no leakage under pressure. Therefore, the casting defects of the nodular cast iron parts of the high-pressure cylinder end cover, such as sand holes, shrinkage holes and porosity, must be strictly controlled. In the actual production process, due to the high content of alloy elements in the high-pressure cylinder end cover, the casting performance is poor, According to the casting process plan formulated by traditional experience, serious defects such as sand hole, shrinkage hole and shrinkage porosity were found in the product during the production of high pressure cylinder end cap ductile iron castings, resulting in low product qualification rate.
(1) Based on the analysis of the original production process plan of the nodular cast iron part of the high pressure cylinder end cover and the causes of the defects of the nodular cast iron part, it was found that the small size of the riser neck, the poor feeding fluidity and the entire pouring were not smooth, resulting in sand holes, shrinkage porosity and shrinkage holes in the nodular cast iron part.
(2) The size of the riser neck was increased, and each riser was changed from 3 to 2 ductile iron castings. The optimized process design ensured the quality of ductile iron castings.
(3) The optimized process simulation shows that the defects such as sand hole, shrinkage porosity and shrinkage cavity on the surface of ductile iron castings have been solved. The product qualification rate has increased from about 90% to more than 99%.
In view of the deficiencies in the production of nodular cast iron parts for the end cap of high pressure oil cylinder, based on the casting CAE technology and using the MAGMA software, the mold filling and solidification process of the original process plan was simulated, and the causes of the defects in the original process plan were analyzed. A new optimized process scheme is introduced to improve the quality of ductile iron castings.