Which keys are used when very high torque of impact type is to be

| Which keys are used when very high torque of impact type is to be transmitted in both directions of rotation?

A. Feather key

B. Woodruff key

C. Saddle key

D. Tangential key

Please scroll down to see the correct answer and solution guide.

A key is an insert which is housed in the key way to fit together a hub or a pulley to transmit torque.

There are different types of keys:

Parallel key or feather key	This is most commonly used key. It is used for transmitting unidirectional torque.
Taper and jib-headed key	It is used for transmitting more torque but not good for high-speed application.
Woodruff key	It is a semicircular key used for transmitting light torque.
Saddle key	These keys are used for transmitting very low torque.
Tangential key	These keys are used when very high torque of impact type is to be transmitted in both directions of rotation. Common applications are found in flywheels, rolling mills etc.
Round key	It is of cylindrical cross-section and is used in assemblies to secure the mating components where the torque is light.