Expansion Fitting - Coupling

Top Definition

Expansion couplings (joints) are one-piece fittings that allow for longitudinal movement to provide expansion and contraction in a metal conduit system. This may happen for a variety of reasons such as when conduit is entering a foundation, from ambient temperature fluctuations, from unintended consequences of long conduit runs, or building design requirements. Made by Crouse-Hinds, OZ Gedney and others, they come in sizes ranging from 1/2" to 5" and are available as a coupling or a connector. The AX version shown is a coupling for Rigid conduit while the TX is for EMT.