Tube Sheet Ligament Thickness Selection and Stress Analysis during Tube Expansion

The article deals with the simple two-dimensional axis-symmetric mechanical model of the technological system of the operation to distribute a steel pipe into a steel pipe grid is considered. The pressure amplitude during pulsed flaring and explosion welding of pipes with pipe grids is given. For solution under the Wilkins method, the pipe was divided into quadrilateral elements. Further, the deformed state was analyzed at a number of characteristic points located on the pipe outer surface and the bushing inner surface. The graph shows the radial displacements of points on the pipe surface in the initial period of time. The non-simultaneity of the collisions and the out-of-phase oscillations indicate bending and bending vibrations of the pipe. The dependence of the node displacements on the bushing inner surface in the radial direction on the deformation time and the dependence of the point radial velocity on the outer contact surface of the pipe on the deformation time are also shown. The dependence of the displacement speed of the points of the nodes located on the sleeve surface on time in the initial period of the process is given. The stressed condition of the system elements is characterized by the occurrence of stress waves generated by pipe being struck and spreading in the bushing and pipe. The process of pipe fastening is analyzed using the model of a flat deformed state. The co-deformation of a pipe and a pipe board with a hexagonal hole arrangement is considered for the case if a single pipe needs flaring inside the pipe grid.