The hull deformation is a significant factor affecting the quality of the shafting alignment. The deep-water submersible vehicle is taken as the research object, by establishing the 3D finite element model of the submersible vehicle, and the hull deformation under the action of gravity, buoyancy and hydrostatic pressure is analyzed when submersible vehicle is in upright floating attitude, and the displacement data of each bearing of the submersible vehicle shaft system is obtained, which offers a reference for shafting alignment of submersible vehicle considering hull Deformations. A method of adjusting the balance of gravity and buoyancy of submarine by spring constraint is proposed, and the displacement scatter plot of the bearing is fitted by the least squares method. The straight line is used as the relative displacement reference line of the shaft system, and the displacement of each bearing of shafting system relative to the reference line is obtained. The analysis results show that the bearing displacement inside pressure hull is smaller than that outside. The difference of support structure of the bearing will result in different bearing displacements. The asymmetric arrangement of the liquid tank inside the submersible vehicle will lead to a larger lateral displacement of the bearing located on the tank.
