Research On Modeling And Control Strategy Of Narrow Gap Welding Process

With the rapid development of urban construction,shipbuilding and nuclear industry,the demand for slabs is increasing.Due to the limitation of existing production equipment and manufacturing technology,most of the thick plate connections can only be welded.When using traditional welding methods,The cost is high,the time is long and the efficiency is low.To this end,to explore a new type of welding.Narrow gap welding technology because of its short time,low energy consumption,heat affected zone is small,high economic efficiency characteristics are favored,but the welding groove narrow and deep lead to its welding process easy to produce side wall fusion bad,And other defects,seriously restricting the quality of welding.Therefore,it is of great significance to study the influence of relevant process parameters on the quality of narrow gap welding.In this paper,the narrow gap welding process modeling and control as the background to carry out research,the main work is as follows:(1)The advantages and disadvantages of narrow gap submerged arc welding,narrow gap tungsten gas welding and narrow gap melting pole gas welding are studied in detail.The narrowest gap melting gas welding with the most promising application is chosen as the research direction.In this paper,two kinds of common welding methods,which are the most widely used,are the most widely used,and the welding method is the best.The welding method is based on arc swing and narrow gap melting based on arc rotation.As the welding program.(2)Based on the detailed analysis of the mechanism of narrow gap welding,the dynamic simulation model of narrow gap welding process based on arc swing and arc rotation is established,and the influence of process parameters on heat input is studied.The influence of quality and the failure of the side wall,the high weld,the convexity is too large,the undercut and other defects are caused,which provides the theoretical basis for the narrow gap welding process parameter matching.(3)The method of dealing with the arc signal is studied,and the noise of the welding process is large,and the Kalman filter can reduce the filtering effect when the noise parameters of the welding process are changed.An adaptive Kalman Filtering method to extract the real welding current signal,through the actual measurement of the new calculation of the modified Kalman filter gain,applied to the welding current signal processing,simulation results show that the welding current measurement noise changes,can still get very good The filtering effect.(4)In order to solve the shortcomings of fuzzy controller in the presence of steady-state error in welding process control,a conventional fuzzy controller is designed and an adaptive fuzzy controller for arc voltage control is designed.The simulation results show that the adaptive fuzzy controller has the best effect,compared with the fuzzy controller,the control effect is better and the steady state error is smaller than that of the PI controller.