What type of coupling is used to connect two shafts?

Mechanical couplings are devices used to connect two shafts together for the purpose of transmitting power or motion. They serve several important functions, such as allowing for slight misalignment between the shafts, accommodating thermal expansion, and providing a means to disconnect the shafts if necessary. Mechanical couplings can be designed to accommodate various applications, including those needing flexibility or rigidity.

While socket, flange, and rigid couplings are specific types of mechanical couplings, the term "mechanical coupling" encompasses all such devices. This broader classification encompasses different designs suited for various applications and environments. Consequently, selecting "mechanical coupling" accurately reflects the general category of connection used for joining shafts together to transmit torque efficiently.