Prediction and controlling for welding deformation of propeller base structure

Abstract

Welding deformation often brings about manufacturing problems such as dimensional inaccuracies during assembly and reduces fabrication efficiency. Prediction and controlling welding deformation can help to improve the quality of welded structures. In this paper, the welding deformation of propeller base structures is predicted by means of numerical approaches and mechanical constraints are proposed to control deformations in welding process. Thermal elasto-plastic finite element method (TEP FEM) is employed to simulate welding process of the base structure. Computed accuracy of welding deformation by TEP FEM analysis is verified by comparing with experimental data of tee joint welding. Results show that welding deformations of the base mainly comprise out-of-plane distortion of ring fringe and radial distortion of cylindrical plate. Exerting mechanical constraints of fixed points at fringe and rigid supports inside cylinder can decrease out-of-plane and radial distortions effectively. The numerical approach adopted in this article can serve as an effective tool to optimize welding process planning in integrated design method.