Rexnord 638017 SR54 225 NB Disc Coupling Hub

The Rexnord 638017 SR54 225 NB Disc Coupling Hub is a Thomas Series 54 hub engineered for a 2.25-inch bore, placing it in Rexnord's SR54 family of hubs designed for disc-type power-transmission couplings. As a hub-only component, it provides the shaft-side interface that is paired with a compatible Rexnord disc pack and center member to form a complete disc coupling assembly used to transfer torque between shafts while accommodating misalignment and axle-end movement. In Rexnord documentation, Series 54 hubs are offered in multiple bore sizes—including 162, 200, and 225—so 638017 specifically corresponds to the 225 bore option within the SR54 lineup. For proper selection and installation, this hub is intended for standard 54-series coupling configurations that pair with Rexnord Thomas 54RDG-disc packs and related hardware to achieve a balanced, robust torque-transmission solution in industrial drives and similar power-transmission applications.