Research On Pressure Straightening Simulation Of Shaft Parts

Shaft parts are important parts widely used in mechanical equipments.Due to heat treatment and other processes,it is easy to cause bending deformation of shaft parts,so it needs precision straightening of shaft parts.At present,many enterprises generally adopt the pressure straightening method for straightening shaft parts.However,the theoretical research of the pressure straightening is not perfect,which makes the process parameters of straightening shaft parts inaccurate,which leads to the low straightening efficiency of shaft type parts and the straightening accuracy is not guaranteed.In the process of aligning shaft parts,the fuselage structure in the straightening process system will also be deformed by straightening force,which will affect the straightening of shaft parts.In this thesis,the pressure straightening of a transmission shaft produced by an enterprise is taken as an example.The finite element method is used to simulate the pressure straightening process of the transmission shaft and the pressure straightening process parameters are obtained.The structure of the "C" straightening machine is analyzed and optimized,so as to improve the stability of the structure of straightening equipment.The main contents of this thesis are as follows:(1)The analysis of the main part of the mechanical structure of pressure straightening device and shaft parts straightening process,expounds the principle of pressure straightening based on straightening stroke control.According to the material mechanics model of pressure straightening,the rules of the fulcrum and pressure point layout are determined.(2)According to the basic analysis process of finite element,the basic theory of elastic-plastic deformation finite element in the process of pressure alignment of shaft parts is obtained,and the yield criteria and strengthening rules that are mainly involved in the finite element analysis of pressure-straightening of shaft parts are determined.(3)The pressure straightening process of shaft parts is analyzed based on finite element method.First,the tensile test of the same material as the shaft and the same heat-treated material as the tensile test is performed to determine the stress-strain rule of the shaft-type part and provide a reliable force energy parameter for the finite element analysis.Then,the direct simulation model of axial component pressure calibration was established,and the relationship between the straightening stroke and plastic deformation was determined.Finally,It is verified by the pressure straightening experiment of shaft parts.(4)The force of the whole straightening process system is analyzed.The finite element analysis of static and dynamic characteristics of the fuselage structure of the pressure straightening device was carried out,and then the design of the body structure is optimized.The influence of straightening process system on the pressure straightening of shaft parts is reduced.In this thesis,a finite element model for pressure straightening of a transmission shaft is established,and the pressure straightening process of the transmission shaft is completely simulated.The deformation laws of the drive shaft at different fulcrum positions were obtained,providing guidance for the pressure straightening of shaft parts.The analysis and optimization of the fuselage structure of the pressure straightening machine provides the basis for the design of the pressure straightening device.