Overhead & Gantry Cranes - Sheaves

A sheave is a grooved wheel with a pulley. It can be part of a block and tackle system. A block and tackle is a system of pulleys with a rope or cable used to lift heavy loads.

Sheaves must be smooth and without surface defects, as these could lead to rope damage. Additionally, sheaves that carry ropes must have close-fitting guards or other suitable devices to guide the rope back into the groove when the load is applied again.

Sheaves must also meet the following criteria:

• Have close-fitting guards to avoid ropes being tangled when the block is lying on the ground with ropes loose. (This is for sheaves in the bottom block.)
• Be of dimensions that ensure they will not become caught in the hoist chain (when used with hoist chains).
• Have a means for lubrication (for all running sheaves). Note: Permanently lubricated, sealed, and shielded bearings meet this requirement.

To learn more about Crane, Derrick & Hoist visit our Crane, Derrick & Hoist Safety Online Training web page.