A Study Of Integral Casting For Lube Oil Pump Based On 3D Printed Sand Mould

In the paper, the forming process of engine lube oil pump casting with internal complex structures and high performance requirements for temperature, pressure and speed was settled by process design, calculation and optimization and making a practical casting plan.The low pressure casting method was chosen to manufacture the lube oil pump casting and the gating system was optimized. The extra pouring gate can result in smooth filling for the molten metal. The design of air vent and riser can make the gas get out in mould. The combination of them insured the smooth filling and progressive solidification of the casting.The whole sand mould with gating system was made by 3D printing,which solved technical problem in manufacturing mould in traditional sand casting process. In addition, 3D printing can avoid the deviation caused by separating and closing moulds in traditional sand casting process. The parameters for laser sintering were 0.2mm for layer depth and scanning interval,21.5w for laser power, 3000mm/s for scanning speed, 58? for sintering temperature of sand mould, 70 ? for sintering temperature of support structure, 190 ? for calcinations temperature and 32 hours for calcinations time. We used ProCAST software to simulate filling and solidification process of the casting. We simulated the pressure-time diagram under 710?, optimized the casting process parameters according to the results of simulation and got the best pressure-time diagram finally. In addition, the pouring temperature under the best pressure-time diagram was optimized and the results showed that the casting quality was best at 710? among 710?, 720?, 730? and 740? and shrinkage porosity was less.Engine lube oil pump casting was manufactured according to the optimizing casting process card. The appearance test results showed that the casting has complete structure and high surface quality. The fluorescence detection, suppression of leakage detection, X-ray detection,mechanical performance testing and metallographic observation results showed that the casting had good microstructure and high comprehensive mechanical properties and it can meet the aviation standards and be used in environment of high temperature, high pressure and high speed.