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Types of keys used in keyed propellers


Parallel Keys: These keys have a rectangular cross-section and are used in straight keyways. They provide a simple and effective means of transferring torque between the shaft and the hub.

Sunk Keys: Also known as rectangular keys, these keys fit into keyways that are cut into both the shaft and the hub. They have tapered sides that fit tightly into the keyway, preventing movement.

Woodruff Keys:These keys have a semi-circular shape and are often used in applications where axial movement of the propeller on the shaft needs to be prevented. They fit into a curved keyway on the shaft and a corresponding slot on the hub.

Tapered Keys:Tapered keys are used in tapered keyways, providing a wedging action that helps secure the propeller onto the shaft tightly.

Gib Head Keys:Also known as feather keys, these keys have a projection, or gib head, that fits into a slot in the hub, preventing axial movement.

The type of key used depends on factors such as the design of the propeller hub and shaft, the torque requirements, the axial movement tolerance, and other specific requirements of the application. Proper installation of the key is essential to ensure the propeller remains securely attached to the shaft during operation. Additionally, routine inspections and maintenance are important to check for any signs of wear or loosening of the key.

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