Rexnord G4ST425 425.ST.CPLG CB SD is a Thomas Disc coupling complete unit. This 425 size coupling features a close bore (CB) configuration and standard duty (SD) design. The all-metal disc pack transmits torque while accommodating misalignment without lubrication.

ST couplings are designed for applications which require the coupling to support a substantial radial load while accommodating angular misalignment. Typical installations include units where one shaft is fully supported in its own bearings, and the other shaft is single-bearing supported. The radial load is transmitted through the coupling to the inner bearing of the other shaft.

Belt drives can be designed to utilize this type of coupling to eliminate a jack shaft bearing and transfer radial loading directly to a machine bearing. Such arrangements are economical and space saving. See the sketches below.

Used for single-flexing applications where light-to-moderate radial loads occur, or may be combined with intermediate solid shaft for floating shaft applications. They do not accommodate parallel misalignment and are not suitable for connecting equipment where both shafts are held rigidly in their bearings.