Industrial Rzeppa Universal Coupling Component Description

A complete Rzeppa coupling assembly consists of two end Rzeppa universal joints plus an intermediate drive shaft. Each universal joint contains 4 core transmission components, together with sealing, locking and lubrication accessories.

Internal Components of Single Rzeppa Universal Joint (Core Transmission Parts)

1. Outer race (Bell housing / Outer ring)Housing component with curved raceways machined on its inner surface. Its outer side is equipped with flange, locking assembly or keyway for connection to equipment shaft ends. It acts as the power input and output housing.
2. Inner race (Star hub / Inner ring)Spline bore internally for connection to the intermediate drive shaft. Curved raceways are machined on its outer circumference, paired with raceways of the outer race. Torque is transmitted via steel balls rolling within the grooves.
3. Cage (Ball cage / Separating cage)Spherical cage with window cutouts to evenly space and retain steel balls. It keeps steel balls on the bisecting plane of the shaft angle to achieve constant velocity transmission, which gives rise to the name “ball cage”.
4. Load-carrying steel ballsNormally 6 balls (8 balls for some models). Assembled between raceways of the inner race and outer race. All steel balls bear torque simultaneously and permit angular misalignment between the two shafts.

Intermediate Connection Section

1. Intermediate drive shaft (Intermediate shaft)Connects the left and right Rzeppa universal joints. External splines at both ends engage the internal splines of the inner races on each side to transmit torque. Available in sliding (telescopic) or fixed-length designs.

Telescopic Rzeppa joint: The intermediate shaft can slide axially to compensate for axial displacement.

Auxiliary Sealing, Locking & Lubrication Parts

1. Dust boot (Bellows)Rubber or polyurethane boot enclosing the Rzeppa cavity, preventing dust, water ingress and grease leakage. Heavy-duty industrial versions adopt metal sealing sleeves.
2. Clamps / Hose clampsFasten both ends of the dust boot onto the outer race and intermediate shaft.
3. Circlips for bores / Retaining ringsAxial positioning components to lock the inner race and prevent shaft components from dislodging.
4. Grease nipple (Oil cup)For filling high-temperature grease to lubricate and maintain steel ball raceways.
5. End cover / Pressure coverSeals the opening of the outer race and compresses sealing elements.
6. Connecting flange / Locking assembly (Hydraulic keyless bushing)Mounting fittings on the outer side of the outer race for coupling with shaft ends of motors and reducers. Industrial models widely adopt hydraulic keyless bushings for keyless installation.