When you have a motor or a gearbox, you will likely see a coupling in action. It connects the two shafts together, transmitting power and allowing slight misalignment between the driven shafts. While they’re typically easy to upgrade or replace, couplings aren’t just for motors and gearboxes. They serve many other purposes as well. Here are some examples of why couplings are important to your machine or gearbox.

Fluid couplings – These fluid couplings operate on the Fottinger principle and transfer torque through transmission fluid. They consist of four basic parts: an impeller, turbine and stator. The turbine is connected to the driver shaft while the stator is located between the driven and driver shaft. A hydraulic fluid is used to transmit power. Once the transmission begins, the fluid transfers torque to the drivetrain. The coupling behavior is similar to that of a mechanical clutch driving a manual transmission.

Fluid couplings – Flowing fluid is used to transfer power through hydraulic systems. This provides a smooth start-up of a belt conveyor and prevents the belt from being damaged by the stresses of the drive. Fluid couplings are most commonly used with squirrel cage motors. They allow for soft, quasi-steady state start-up and acceleration. There are many applications for these types of couplings. If you’re looking for a new coupling, make sure to check out the different types of couplings available.

Flexible couplings are another type of coupling. The flexibility of a flexible coupling is essential for transmitting power to rotating equipment. However, you should consider the maximum rotational speed of your equipment before you select a coupling. Otherwise, the foundations and subsequent motion of the bearings could result in a misalignment. Foundations should also be kept within the tolerance limits of the coupling you choose. Flexible couplings must couple two pieces of rotating equipment with shafts or flanges.

The mechanical flexibility of a gridtype coupling is the most important characteristic of this type of coupling. It connects two shafts in a mechanical system and transfers axial thrust to the motor. Because of this, the weight of the rotating element or shafting needs to be carried by a special thrust bearing in the motor. To operate at this level, the motor needs to be rated for the weight of the rotating element. Most rigid couplings are split configurations along the axial centerline.

Gear couplings are another type of mechanical coupling. They have two shaft hubs with internal gear teeth and are typically large and heavy. A floating spacer separates the two gear components. Ideally, a gear coupling is lubricated in order to avoid wear and tear of the rubbing surfaces. Another type of flexible coupling is the roller-chain coupling, which is another type of flexible coupling. The latter type uses hubs mounted on shafts and is typically applied in low-speed services.

In addition to being durable, fluid couplings can be extremely effective. They can handle high torques and have an efficiency rate of 94 percent or higher. If you’re driving a vehicle that tends to stop and go a lot, it will typically operate in its lowest-efficiency range. Using the fluid coupling in this way will help to increase fuel economy, but it will not give you a 100 percent power-transfer efficiency.