Research On The Welding Deformation Characteristics And Control Of Fillet Weld Based On The Numerical Simulation

The existence of the welding residual deformation will not only affect the performance and service life of the welded structures,but also bring considerable difficulties to subsequent assembly.So it greatly affect the quality of the welded structures and the production efficiency of the enterprise.While the current method of deformation correction by flame using in the shipyard is difficult and time-consuming.In order to achieve the accurate prediction and effective control of welding deformation,this paper take the typical T-joint of the hull structure as the research object and do the following work based on the thermal elastic-plastic finite element method(FEM):(1)Considering the performance parameter of the material changes with temperature,the method of sequentially coupling finite element analysis of thermal-mechanical was carried out on the T-joint welding structure by the finite element software ANSYS,in order to get the results and the distribution rule of the welding temperature field and residual stress and deformation.Verify the accuracy of the calculation results by comparing with the literature,and take this model as the basis of the subsequent research.(2)The welding deformation characteristics and distribution rules of the T-joint under the change of structure surface size,welding speed,welding angle size,thickness of the panel and welding sequence are studied respectively based on the thought of control variables.(3)The welding angular distortion characteristics of T-joint are analyzed through orthogonal experiment design method under the action of the selected factors,such as thickness of the panel,welding current,welding voltage,welding speed.Then the primary and secondary order of the various factors influencing the welding deformation is determined,and the optimal process parameters combination of the minimal welding deformation is selected out by this method.(4)The welding deformation control function of the plastic anti-deformation method is discussed on the basis of the prediction of welding deformation.Considering the distribution characteristics of welding distortion and the processing conditions and accuracy requirement of the practical production,two ways of variable camber and same radius are adopted to extract and apply the anti-deformation.Then two instances are selected for simulated analysis.Grid method is used to measure the flatness of plate of the T-joint.The results show that the anti-deformation method can realize the control of welding deformation.(5)The welding deformation characteristics and distribution rules of the plastic anti-deformation method are discussed under the separate change of factors such as structure surface size,welding speed,and thickness of the panel.Then the welding deformation control of the stiffened plate structure in hull construction is researched.All these made us further understand the welding residual deformation control effect of the plastic anti-deformation method,so as to provide reference for the practical production of the shipyard.