Expansion Joint Manufacturers Direct Supply, Wholesale Sales Pricing. An expansion joint is a flexible element that effectively compensates for axial deformation. For example, the expansion joint with high axial flexibility and ease of deformation, welded to the shell of a fixed tube sheet heat exchanger, can compensate for the thermal expansion difference caused by the difference in wall temperature between the tube and shell, reducing their axial load, thereby reducing the temperature difference stress between the tube, tube plate, and shell, and avoiding strength failure, instability failure, and tube pull-out failure. There are many types of expansion joints, commonly used ones include bellows, ring plate welding, and clamped shell structures, among which the bellows expansion joint is widely applied, while the ring plate welding expansion joint is only suitable for atmospheric or low-pressure conditions.