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Mechanical Flexing Couplings

The mechanical flexing couplings accept misalignment from rocking, rolling or sliding of metal surfaces. All metal mechanical flexing couplings require lubrication.

Mechanical flexing couplings are:
  • Gear coupling.
  • Grid coupling.
  • Roller chain coupling.

Gear Couplings

Gear couplings transmit the highest amount of torque and the highest amount of torque in the smallest diameter of any flexible coupling.
Each coupling consists of two hubs with crowned external gear teeth. The hubs mesh with two internally splined flanged sleeves that are bolted together. Gear couplings accommodate angular and axial misalignment by the rocking and sliding of the crowned gear teeth against the mating sleeve teeth. Parallel misalignment is accommodated by having two adjacent hub/sleeve flex points. Gear couplings require periodic lubrication depending on the application. They are sensitive to lubrication failures but if properly installed and maintained, these couplings have a service life of 3 to 5 years and in some cases, they can last for decades.

Grid Couplings

Grid couplings consist of 2 radially slotted hubs that mesh with a serpentine strip of spring steel the grid provides torsional damping and flexibility of an elastomer but the strength of steel. Grid couplings transmit torque and accommodate angular, parallel and axial misalignment from one hub to the other through the rocking and sliding of a tapered grid in the mating hub slots. The grid cross-section is generally tapered for better hub contact and easier assembly. As there is movement between contacting hub and grid metal parts, lubrication is required.

Roller Chain Coupling

Roller Chain type couplings consist of two radially sprocketed hubs that engage a strand of double pitch roller chain. Chain couplings are used for low to moderate torque and speed applications. The meshing of the sprocket teeth and chain transmits torque and the associated clearances accommodate angular, parallel and axial misalignment.

Chain couplings require periodic lubrication depending on the application. The lubrication is typically brushed onto the chain and a cover is used to help keep the lubrication on the coupling.


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