ZURR COUPLINGS are famous for their High Torque to Size ratio thus offering a compact assembly capable of Transmitting high loads at high speeds. ZURR Gear Couplings are manufactured on precision CNC Machines and Gear teeth are manufactured by precision hobbing and shaping equipment to exacting standards of tooth finish, profile, and spacing. All parts are magnetic particle inspected to assure soundness and reliability.

Balancing is performed by components on sensitive balancing machines to assure smooth, vibration-free operation of the installed coupling.

Parts are heat-treated to controlled specifications to provide maximum strength and coupling life.

All the standard practices used to manufacture our conventional Class I couplings are used, plus any special requirements deemed necessary for a specific application including material property tests, ultrasonic tests, 100% inspection, assembly check balancing, etc.

The standard line is rated at full 1/4° misalignment per gear mesh. The hubs, sleeves, and spacer are made of high quality AISI 4140 heat treated steel with nitrided gear teeth, providing optimum strength and hardness properties. Fasteners are twelve point Grade 8 bolts and matching self-locking nuts.

The gear tooth is fully crowned. The flanks of the teeth are crowned so that the tooth thickness is greatest at the center of the tooth

These Gear Couplings are supplied in 3 forms :- RIGID, HALD RIGID & HALF FLEXIBLE and FULLY FLEXIBLE GEARED COUPLINGS.

Standard Size Range – 100 to 118.


ZURR Gear coupling consists of hubs with multi crowned teeth at Flank, tip and chamfering on teeth.

The gear tooth is fully crowned. The flanks of the teeth are crowned so that the tooth thickness is greatest at the center of the tooth.

This assures larger contact area per tooth for higher court capacity and puts more teeth in contact at a given angle. The crowned flank eliminates end-of-tooth loading, provides optimum load distribution, and corrects for all types of misalignment with minimum backlash.

Tips of the teeth are crowned with a radius equal to the outside radius of the gear element. The crowned tip contacts the root of the internal gear teeth in the external sleeve, accurately piloting the sleeve and permitting minimum diametric sleeve clearance to assure good dynamic balance characteristics.

Faces of the teeth adjacent to the tips are crown chamfered to eliminate interference with sleeve tooth fillets, allowing true involutes flanks of gear teeth to be in contact with the sleeve tee regardless of operating angle.

Custom High Performance Designs
These couplings are custom-designed to your needs, whether they involve weight or size limitations, high temperature, high speed, or extreme misalignment requirements. We would select a material suitable for your application from a variety of choices including 1045, 4140 Nitrided, 4340 Nitrided, Nitralloy, 8620 or 9310 carburized.

Fastener selection again would be dependent on your requirements. They could be Grade 5, Grade 8, Aircraft type, Inconel, etc.

Tooth design would be fully crowned and specifically designed to your needs which could be as high as 7-1/2° per mesh. Coupling balance would also be based on your requirements.


A) RADIAL – When axes of connected shafts are parallel but not in the same straight line

B) ANGULAR - When axes of connected shafts intersect at center point of coupling but not in the same straight line.

C) COMBINED RADIAL AND ANGULAR - When the axes of connected shafts do not intersect at point of coupling and are not parallel.