Analytical assessment of the residual deformations and stresses in the process of the deepwater vehicle manufacturing using finite-element method
The paper gives calculations for welding deformations appearing in the process of the deepwater vehicle manufacturing. These calculations are required to develop technological measures designed to reduce the scope of fitting-up activities and the vehicle manufacturing costs. A new procedure has been developed for the calculations of welding deformations on complicated spatial structures. This procedure is based on welding deformation theory and finite-element method. The equivalent forces are defined considering thermal processes occurring while welding, and the structures themselves are approximated by means of plate-axial finite elements. The deformations are defined considering the sequence of six technological stages of assembling and welding, including also structural stiffness increase in the assembly process and change of its boundary conditions. The procedure can also be used to assess the impact of the residual deformations and stresses the structure accepted while manufacturing on its operational parameters, namely, ship hull structural strength