Expansion joint
From Wikipedia, the free encyclopedia
An expansion joint is an assembly designed to safely absorb the heat-induced expansion and contraction of various construction materials. They are commonly found between sections of sidewalks, bridges, railway tracks, piping systems, and other structures.
The "assembly" can be as simple as a caulked separation between two sections of the same materials. More recently, expansion joints have been included in the design of, or added to existing, brick exterior veneer walls for similar purposes. In concrete and concrete block ("CMU") construction, the term applied is "control joint", but serves similar purposes.
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 a 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.
