Prediction of Welding Deformation and Residual Stress of a Thin Plate by Improved Support Vector Regression

Abstract

Thin plates are widely utilized in aircraft, shipbuilding, and automotive industries to meet the requirements of lightweight components. Especially in modern shipbuilding, the thin plate structures not only meet the economic requirements of shipbuilding but also meet the strength and rigidity requirements of the ship. However, a thin plate is less stable and prone to destabilizing deformation in the welding process, which seriously affects the accuracy and performance of the thin plate welding structure. Therefore, it is beneficial to predict welding deformation and residual stress before welding. In this paper, a thin plate welding deformation and residual stress prediction model based on particle swarm optimization (PSO) and grid search(GS) improved support vector regression (PSO-GS-SVR) is established. The welding speed, welding current, welding voltage, and plate thickness are taken as input parameters of the improved support vector regression model, while longitudinal and transverse deformation and residual stress are taken as corresponding outputs. To improve the prediction accuracy of the support vector regression model, particle swarm optimization and grid search are used to optimize the parameters. The results show that the improved support regression model can accurately evaluate the deformation and residual stress of butt welding and has important engineering guiding significance.

Prediction and optimization method for welding quality of components in ship construction

“…Welding process is one of the vital industrial technologies in ship segment construction 3 , 4 . However, in the welding process of ship components, the local uneven heating and local uncoordinated plastic strain of metal materials are most probably leading to large residual stresses 5 , 6 . This will cause a reduction in the static load capacity and fatigue strength of the ship components.…”

Research on welding quality prediction methods

“…Such a high proportion of welding workload and cost represents the core position of welding process in modern ship construction. However, it is difficult to avoid that the welding process of ship components due to changes in process parameters and environmental factors, resulting in unqualified welding quality and thus affecting the production schedule [4] [5]. However, most of the current shipbuilding enterprises in the welding quality control is still using a low level of automation of static control, that is, to take the form of quality plan issued, after the sequence of production inspection and quality statistical reports.…”