关键词: 螺杆转子, 响应面法, 缩痕深度, 翘曲变形

Abstract: Aiming at the problems in the complicated process and the difficulty to control the precision of traditional metal type screw rotor， a new injection-molding method with a screw rotor was proposed to replace the metal type rotor with a plastic material. The Moldflow software was used to analyze the injection molding of the tooth surface of the screw rotor using glass-fiber-reinforced nylon as a raw material. The depth of shrinkage and warping deformation were taken as quality criteria to screen and analyze 7 process parameters affecting the molding quality of plastic parts， and 3 process parameters that had the greatest impact on the 2 quality standards were determined. A response surface experiment was designed through the BBD experiment. The influence of injection process parameters such as melt temperature， holding time， and holding pressure on the shrinkage depth and warp deformation was studied. A polynomial regression response model for minimum shrinkage depth and warp deformation was obtained. Using regression model， the optimal combination of process parameters was determined to be a melt temperature of 281.0 ℃， a pressure holding time of 18.7 s， and a pressure holding pressure of 115.7 MPa. The results indicated that the values obtained from the numerical simulation and prediction with the model were similar along with errors of 3.75 % and 0.53 %， respectively.

Key words: screw rotor, response surface method, indentation depth, buckling deformation