The function of the shaft coupling is to firmly connect the driving shaft and the driven shaft in different mechanisms for synchronous rotation, and transmit the torque directly to the working machine.
The shaft of the motor product is the driving shaft, and the shaft of the driven device is the driven shaft. usually, the shaft of the equipment being dragged is the deceleration and force boosting link of the equipment, avoid low speed, large torque motors have low operating efficiency, defects such as small power-to-volume ratio.
In the drag test of drive motor products, shaft couplings are widely used and very critical load test devices.

Cast Iron Elastic Sleeve Pin Shaft Coupling is widely used on the industrial gearbox.
According to the driven equipment’s operating precision requirements, different shaft couplings will be used. shaft coupling can be divided into rigid type shaft coupling and flexible type shaft coupling if distinguish from the connection performance. the rigid types of shaft coupling can realize the height coincidence of the motor’s shaft and the driven equipment. thus, the consistency requirement is very high between the motor’s installation benchmark and the equipment, and it requires the motor body’s connecting shaft must be strictly in-line the equipment body ;
In order to ensure that there is no jamming or resonance caused by over-positioning between the motor body and equipment body, it requires extremely coordinate precision to the shaft coupling’s alignment precision, shaft coupling, and the driven shaft. which affects directly the final installation consequences to achieve smooth power transmission demand.
The basic performance requirements to the shaft coupling
(1) Mechanical properties:
As a key component for torque transmission, the shaft coupling is not allowed to deform and crack during the AC asynchronous motor running operation, which seriously endangers stable and reliable operation issues.
(2) Buffering function.
During the AC asynchronous motor running under loading conditions, both the AC motor body and the driven equipment may happen axial or radial displacement. Especially for the running occasions with a full load or shock load, it is inevitable happen different degrees vibration problems, The shaft coupling must have the corresponding endurance ability, and play a certain function in restraining and buffering, ensure the safe running between the AC motor and driven equipment.
(3) Mobility.
When some unavoidable errors or displacements occur in the drive motor and driven equipment connected to the shaft coupling due to manufacturing, installation, and use factors, the shaft coupling should have the corresponding containment performance. Therefore, the shaft coupling design cannot only be satisfied with the ideal mechanical installation but also compatible with the inevitable small-displacement during the drive motor running operation.
(4) Self-balancing effect.
The shaft coupling is a key component that rotates with the motor shaft. In order to effectively avoid the adverse effects of the shaft coupling on the motor’s operation and equipment running, the shaft coupling balance must meet the requirements, for related shaft coupling’s technical parameter of all fixed holes diameter, position, distribution, the keyway size on the shaft, etc.
Please consult SDT Transmission Team if you have more queries: