Research On Incremental Forming Technology Of Connecting Pipe Flange

As an important part of turbocharged turbine engine,the connecting pipe of intercooler is mainly used for the transportation of compressed gas in the engine.It is a heterosexual thin-wall part including intake pipe and outlet pipe.The process of pipe bending and pipe end diameter change has always been a difficult point in the manufacture of this part.At present,the domestic grasp of pipe bending technology has been quite mature,but there is still a certain gap between the flanging technology and foreign countries.Therefore,it is of great significance to carry out the research of its related forming process.This paper takes the intake pipe parts of a brand automobile engine as the research background,analyzes the characteristics of the forming process and the present situation of production and manufacturing,and puts forward the research contents and key technical problems of this paper on the basis of comprehensively discussing the problems encountered in the actual production and the existing technical means.Firstly,based on the theory of plastic mechanics,the feasibility and influencing factors of incremental forming flanging of connecting pipe are analyzed,and the mathematical expressions of forming process and deformation degree are given.According to the forming principle and motion relationship of stainless steel pipe flanging,the reasonable production process scheme of stainless steel pipe flanging is determined and the reasonable tooling is designed.The influencing factors of the process are analyzed and calculated,and the possible defects and causes in the incremental forming process of the pipe end are predicted,so as to make theoretical preparations for the flanging process.The finite element model of pipe end incremental forming flanging is established.Based on ABAQUS analysis software,the distribution laws of equivalent stress,strain and pipe wall thickness in the forming process are obtained.Combined with the experimental method,the primary process parameter combination is obtained by taking the standard parts as the research object.Taking the forming quality as the index,the factors affecting the instability in the process of long cone tube expansion deformation are analyzed,and the improved methods of split forming are put forward.At the same time,other defects that may appear in the forming are summarized and analyzed,and the micro and macro formability of the forming qualified parts is verified by the experimental methodFinally,the forming law and deformation characteristics of incremental forming flanging are studied from the aspects of forming force,distribution of stress,strain and thickness,flanging height and minimum thickness.The effects of spindle speed,feed speed,friction and lubrication on the forming force are analyzed,and the influence of forming pass on flanging height and minimum thickness is obtained.the experimental results are in good agreement with the finite element simulation results,which provides a theoretical reference for the development and practical production of forming equipment.