Analysis And Research On The Formation For Frame Of Jaw Crusher Based On Virtual Manufacturing

The frame accounts for a big proportion of the whole weight in jaw crusherwith the casted50%and the welded30%respectively. Currently, most of theframes made in our country are castings, while the frames, even the movablejaws that widely used in foreign countries are weldings. During the casting andwelding processes, materials surfer complicated physical and chemical actionswhich refer to the aspects like elevated temperature, heat transmission,metallurgy and mechanics etc. Both of the processes induce significant thermaland residual stress which may cause defects and deflections, affect thedimension accuracy and mechanic properties directly, even induce themalfunction of parts. The simulation of casting and welding processes canprovide a theoretical basis for the practical processes. It has a significant effecton optimizing the process, enhancing dimension accuracy and service life. Themain work of this paper is as follows:1) The simulation on the welding process of the frameBased on the finite element analysis software ABAQUS, the frame wasmeshed and the materials were assigned. Internal heat generation method wasapplied to simulate heat resource and model change ability to simulate the material filling process. Necessary boundary conditions were applied andsubprogram was compiled in Fortran to simulate the heat resource and itsmovement. The temperature and stress field of the frame were calculated bysequence coupling algorithm method.The transient temperature and stress field and residual stress field duringthe welding process were obtained. The results show that the stress isconcentrated around the weld bead, and the highest amplitude exceeds500MPa.The further away from the weld bead, the less the stress amplitude is. Afterpreheating, the amplitude of residual stress decreases to454MPa, decreases by13.5%. After the postweld heat treatment, the amplitude of residual stressdecreases to292MPa, decreases by44.4%.2) The simulation on the casting process of the frameThe casting process was simulated based on some proper assumptions. Thegating system was built in finite element analysis software ProCAST. InPreCAST module, the frame was meshed, materials and proper runningparameter were assigned, and the boundary conditions for calculating heattransfer and stress field were defined.The transient temperature and stress field and the flow behavior of theliquid metal during the casting process were obtained. The results show that,during the filling process, the level of liquid metal raised steadily, the cavity wasfilled up with the liquid metal after6.7s. There were no obvious splash andinvolved air. The liquid level in the open risers decreased during the cooling process, and complemented the solidify contraction of the frame very well.Comparing the stresses in x, y, z directions, we can conclude that the internalstress was induced mainly by the mechanical block of sand during the solidifycontraction process. The stresses mainly appear in the corners and the jointsbetween the open risers and the frame, and the highest amplitude of equivalentstress exceeds300MPa. The simulation results provide a theoretical basis bothfor the practical casting and the further residual stress reducing process.