Overhead & Gantry Cranes - Brakes for Hoists

Independent hoisting units of cranes must have a minimum of one self-setting brake (also called a holding brake). It must be applied directly to the motor shaft or some part of the gear train. Cranes with power control braking that deal with hot metal must have at least two holding brakes.

Hoisting brakes must meet requirements regarding thermal capacity, automatic activation, adjustments, over speeding, and drums and discs. They must also meet the following hoisting torque requirements when the brake is activated:

• 100 percent when used with a mechanical control braking
• 125 percent when used with all control braking other than mechanical
• 100 percent (each) if there are two holding brakes

Power control braking (for example, regenerative, dynamic, or counter-torque braking) or mechanically controlled braking must be able to safely control lowering speeds for rated loads. As with hoist braking, the control braking system must have ample thermal capacity for the frequency of operation required by service.

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