Numerical Simulation Study On Fracture Splitting Of Splitting-parts

Fracture splitting process is a new process for splitting-parts,which derived from the development of automobile industry in recent years.It breaks through the traditional idea of separate machining and matching position in mechanical cutting.The self-locking is formed by using the uneven fracture surface of the parts after the fracture splitting,which can not only improve the meshing accuracy of the cover end and the main section,but also enhance the bearing capacity of the part.Compared with the traditional cutting method,the fracture splitting process can reduce the processing procedure,save the finishing equipment,reduce the material and the production cost,etc.It plays a key role in improving the machining quality and overall working performance of splitting-parts.With the popularization of fracture splitting technology in the manufacture of connecting rods,as well as the application of splitting-parts such as crankcase housing,some new problems and phenomena have appeared.First of all,with the demand for lighter weight and higher output power of engine,the requirement for the performance of engine connecting rod materials is also higher.With the development of new materials for engine connecting rods,the mechanical strength and the yield strength of the connecting rods are increased as well as the Machinability of the connecting rod material.But the defects of the parts or the damage of the equipment and clamp are frequently occurred in the actual production of the connecting rods.In addition,with the popularization of fracture splitting processing technology in the manufacturing of connecting rods,the technology of fracture splitting is forwarding to crankshaft housing and reducer housing bearing parts.However,the material of crankcase housing and reducer housing is different from connecting rod material,so the mechanism of expansion and the setting of the fracture splitting parameters will need to be discussed.In view of the above problems,with the help of the theory offracture mechanics,finite element numerical simulation and experiment,the paper selects typical splitting-parts,and carries out the relevant research work on the fracture splitting processing technology of splitting-parts.The main achievements of the paper are as follows:(1)According to the characteristics of fracture splitting and the relevant technical requirements of splitting-parts,The fracture nature of plastic material and brittle material are determined respectively,and the design force and fracture criterion of brittle material and plastic material are determined according to the theory of fracture mechanics.(2)According to elastic-plastic fracture mechanics,the numerical simulation analysis of fracture splitting of connecting rods have been carried out.According to the simulation results,the machining allowance requirements,depth of the groove and the corresponding fracture splitting load were determined.And the theory and simulation results are verified by experiments.Thus,the fracture parameters design process of elastic-plastic material about splitting-parts were determined.(3)Applies the theory of brittle fracture splitting design load to design 6DL engine cylinder block bearing block,through simulation analysis and corresponding tests,the theory for machining brittle splitting-parts is verified,and the parameters design process for brittle material splitting-parts is determined.(4)Accord to fracture splitting parameters design process of brittle materials splitting-parts,the simulation of reducer housing bearing seat was carried out.on the basis of the simulation result,the parameter of groove and fracture force were determined.In line with above,the main parameters of cylinder were selected.Also,other facilities of this device were determined to completed general design.