Research On Optimization Of Welding Process For Abnormal Joints And Dissimilar Metals

In this thesis,the problems and requirements of welding thin-walled parts and different steel materials in an elevator manufacturer are studied.When welding thin-walled T-joints,the company hopes to improve production efficiency by optimizing process parameters on the premise of ensuring welding quality.In the welding of thin-wall Y-joints,in order to ensure the subsequent assembly accuracy,the company hopes that its maximum deformation does not exceed 1.5mm.When welding dissimilar steels the company hopes to meet the welding residual stress requirements by optimizing the welding process parameters under the premise of ensuring good welding quality.Based on the above-mentioned needs of the enterprise,this thesis optimizes the welding process parameters through numerical simulation to meet the relevant needs of the enterprise.Based on the thermo-elastic-plastic finite element theory,the finite element software Simufact.welding was used to simulate the welding temperature field,stress field and deformation of the thin-walled T-joint.The effects of different welding process parameters on the welding temperature field were compared and analyzed.The welding parameters were optimized based on the orthogonal test method and the residual stress and deformation of the j oint were obtained.The residual stress of the actual welded j oint position was measured by the blind hole method,and the correctness of the simulation results was verified.The optimized welding parameters meet the relevant requirements of the enterprise.In the actual work,it is found that the welding sequence has a great influence on the deformation of the thin-walled Y-joint.In this thesis,the welding sequence is studied and optimized.The welding residual stress and deformation of thin-wall Y-j oints caused by different welding sequences with auxiliary support and without auxiliary support are studied,and the optimal welding scheme is obtained.The correctness of the simulation optimization results is verified by the actual welding and measuring the deformation of the Y-joint.This optimized welding solution meets the technical requirements of the company.The numerical simulation of temperature field,stress field of Q345/316L dissimilar steel welded joints was carried out.The effects of groove angle,number of weld layers and weld interval on the residual stress distribution of dissimilar steel welded joints were studied.Optimize the welding process parameters by orthogonal test method,so as to effectively control the welding residual stress to meet the technical requirements of the enterprise.The correctness of the simulation study was verified by tensile test,vickers hardness test and residual stress test.The optimized welding parameters meet the welding technical requirements of the company for dissimilar steel.In this thesis,the temperature field,residual stress and deformation of T-joint,Y-joint and dissimilar steel welding are studied.The welding process parameters are optimized according to the needs of the enterprise.The research results can meet the technical requirements of the enterprise and improve the product quality for the enterprise.Improving production efficiency has played a beneficial role.