Stress analysis of V-shaped expansion joints under internal pressure

A composite shell type, V-shaped expansion joint is analysed for the membrane and bending stresses induced in circumferential as well as meridian directions under internal pressure loading. The expansion joint consists of a toroidal shell of positive curvature, a conical shell and a toroidal shell of negative curvature, framing into a circular cylindrical pipe. Bending theory of shells of revolution has been used for the analysis. Toroidal shell elements have been analysed using Clark's asymptotic solution. Numerical results for eight different geometries of the expansion joint are evaluated using a FORTRAN computer program. The variations of stresses along the meridian of the composite shell are plotted for different shell geometries. The maximum values of the stresses and their locations on the meridian are tabulated. It has been established that the meridional bending stress is the maximum of the four stresses for all geometries of the joint, and hence governs the design of V-shaped expansion joints under internal pressure loading.