Dynamics Simulation And Optimization Of Main Transmission Parts Of Multi-station Cold Upsetting Formers

With the coming of the Fourth Industrial Revolution,the modernization of construction is developing rapidly.The market of the multi-position cold upsetting formers is getting bigger and bigger,and the improvement of cold upsetting technology is imminent.Combining the cold upsetting technology at home and abroad,consulting a large number of relevant literatures and related documentation on the Internet,applying modern mechanical design theory and optimization simulation analysis method,aiming at the problem that the cold upsetting products in most enterprises have low accuracy,this thesis researches the main drive parts from three aspects,which are kinematics,multi-body dynamics and finite element analys is.Through the simulation and optimization of the motions and structure characteristics of the main drive parts,the motion parameters of the main drive parts and the stability of the work are improved.At the same time,the product testing device for parameter optimization of main drive parts is designed,which can test the quality of the products of main drive parts after simulation optimization.Firstly,according to product performance parameters,the three critical motion parameters,which are the length of crankshaft,the lengths of connecting rods,and the mass of the sliding table,are determined.The software NX is used to structure the 3D solid model for the main drive parts of DBP-136 multi-station cold upsetting formers.Without considering the effects of friction and load resistance,the kinematic and multi-body dynamics analysis of the three-dimensional model is carried out,and then the maximum stroke of the slide table in the main drive parts,the change trend and the minimum value of forging force in the final working stage are obtained.Secondly,the rigid-flexible coupled theory is applied to structure the rigid-flexible coupled model for the main drive parts of the multi-station cold upsetting formers.Through ADAMS software,the sliding table of the main drive parts of the multi-station cold upsetting former is treated flexibly,and the rigid flexible coupling dynamic model is obtained.Combining with the result of multi-body dynamics analysis,dynamic analysis of rigid-flexible coupled dynamic model is carried out.The changing trend and extreme values of the sliding table forging force in the main drive parts are obtained.Due to the flexibility of slide table in rigid flexible coupling model,the sliding table itself will produce slight deformation during movement,so modal analysis is carried out for sliding table.The analysis result shows that the small deformation in the motion process will not affect the vibration characteristics of the sliding table.This method verifies the rationality of the design of the motion parameters of the main drive parts,satisfies the demand of the cold upsetting product of the type multi-position cold upsetting former,and provides the parameter basis for the subsequent lightweight design.Thirdly,the finite element analysis software is used to do the finite element analysis for the main drive parts of the multi-station cold upsetting formers:through static analysis,the crankshaft's stress-deformation image is obtained,the weakest part of the crankshaft--the circular angle of the shaft is found;through modal analysis and harmonic response analysis,the frequency and vibration mode of the crankshaft are extracted,which verify that the crankshaft structure characteristics in the main driving parts meet the requirements.According to the analysis results,aiming at the change of weak position and vibration type,the optimization of the round radius of shaft neck is proposed.Finally,basing on the optimization results of the motion parameters of the main drive parts mentioned above,the product testing device of parameter optimization of main drive parts is designed,which test the size parameters of the optimized main drive parts.It verifies that the methods of multi-body dynamics simulation and optimization of the main drive parts in this article are beneficial to improve the motion stability of main drive parts and improve the processing accuracy of cold upsetting products.