Research On Control Method Of Roller Hemming Quality Of Autodoor Waistline

The waistline of autodoors is the modelling characteristic line throughout automotive body,which is an important performance of the automotive modelling competitiveness.And it’s of vital importance among the quality evaluation of entire autodoor.However,waistline has quite a lot roller hemming defects,which can not be easily solved,due to its special modelling.So it is meaningful to do research on roller hemming of waistline to improve its forming quality,from which the quality of the entire vehicle will benefit.Based on the previous studies,this study does research on roller hemming of waistline,analyzes the process and important parameters,designs a character panel,combines finite element simulation software AutoForm and robot roller hemming experiment,uses orthogonal test and response surface to study the quality control method of roll-in/out and hemming thickness of waistline.The main achievements of this dissertation is as detailed below.(1)Study on roller hemming process and defect of waistlineThe roller hemming process,main defect performance and detection method are analyzed and summarized.For autodoor waistline,face angle and corner radius are significant geometrical characteristic parameters,whose influence on roller hemming process is studied.(2)Study on the forming characteristic of roller hemming of waistlineBased on the analysis of practical autodoor waistline characteristic,a character panel is designed and used to do simulation modelling including flanging and hemming.The experiment bench is designed and built to carry out roller hemming experiments,which verifies the accuracy of simulation model.Through simulation results,the changing process of forming characteristic including stress,strain and roll in/out is analyzed.(3)Study on the influence rule of process parameters on roller hemming quality of waistlineBased on roller hemming technology research,vital process parameters which has influence on hemming quality of waistline are choosen.Orthogonal test with 7 factors and 3 levels is proposed,according to which simulation tests are carried out.The influence rule of process parameters on roll-in/out and hemming thickness is given and the reasonable values of parameters are analyzed to guide roller hemming process.The study shows that flanging height,gap and roller diameters have significant influence on forming quality.(4)Study and application of quality control method of roller hemming of waistlineResponse formulas are established through response surface methodology,which uses face angle,corner radius and flanging angle as input variables.The output variables are roll-in/out and hemming thickness.The formulas are used to predict roller hemming quality and the optimization method of roller hemming quality is given.Through the application on practical autodoor part,the prediction and optimization methods of roller hemming quality of autodoor waistline are proved efficient.