An elastic coupling (also called flexible coupling) is a mechanical device that connects two rotating shafts to transmit torque while compensating for shaft misalignment, absorbing vibration, and damping shock. It is a core component in power transmission systems, widely used in industrial machinery, automotive, marine, aerospace, and other fields.

1. Definition & Core Functions

An elastic coupling is a shaft coupling that uses elastic elements (metallic or non‑metallic) to achieve flexible connection. Its primary functions include:

Torque transmission: Reliably transfer rotational power between driving and driven shafts.

Misalignment compensation: Accommodate axial, radial, angular, and composite misalignments caused by installation errors, thermal expansion, or foundation settlement.

Vibration & shock absorption: Reduce torsional vibration, dampen impact loads, and lower system noise.

Equipment protection: Isolate resonance and prevent damage to connected machinery (motors, pumps, gearboxes, etc.).

Torsional flexibility: Allow limited torsional deflection to smooth out torque fluctuations.

2. Working Principle

Elastic couplings work by utilizing the elastic deformation of their internal elements:

Two hubs are mounted on the driving and driven shafts.

An elastic element (rubber, polyurethane, metal spring, diaphragm, etc.) is installed between the hubs.

When torque is applied or misalignment occurs, the elastic element deforms to absorb displacement and vibration while maintaining power transmission.

After the load is removed, the element returns to its original shape, ensuring continuous operation.