Rigid couplings do not permit radial or axial motion in the shaft between the driver and the driver unit, so they operate as a single shaft. Rigid couplings are primarily used in vertical applications. A few types of rigid couplings include, flanged, split and compression.
Flanged couplings comprise of 2 halves, one on the driver shaft and the other on the driven shaft. Once bolted together they form a solid connection. Flanged couplings are most often used in vertical pump shafts.
Split rigid couplings are basically a sleeve that is split horizontally along the shaft and held together with bolts. They are clamped over the adjoining ends of the driver and driven shafts, forming a solid connection. Clamp couplings are used primarily on vertical pump shafting.
Rigid compression couplings are comprised of three pieces, the core and two coupling halves that apply force to the core. When the coupling halves are bolted together, the core is compressed down on the shaft by the two halves and the resulting frictional grip transmits the torque without the use of keys.