Expansion joint is an assembly designed to safely absorb the heat-induced expansion and contraction of metallic parts. They are commonly found between sections of sidewalks, bridges, railway tracks, piping systems and other structures. Pipe expansion joints are necessary in systems that convey high temperature commodities such as steam or compressed air. One type of expansion joints for pipe systems is bellows, which can be manufactured from metal or an elastomer such as rubber. The bellows are designed to withstand the internal pressures of the pipe but are flexible enough to accept axial deflections.