Hoist brakes or holding brakes

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Hoist brakes are essential for crane safety

Hoist brakes are an essential safety feature of overhead cranes. Designed to hold a load when the hoist motor is not running, these brakes reduce the risk of falling loads that could result in injury and property damage.

This section specifies the performance requirements of hoist, or holding, brakes. It also calls for an additional control braking mechanism to prevent overspeeding – that is, to prevent hoists from exceeding a predetermined operating speed.

OSHA 1910.179 Overhead & Gantry Cranes Regulations

The following excerpt is taken directly from OSHA 1910.179.*

Brakes for hoists

Each independent hoisting unit of a crane shall be equipped with at least one self-setting brake, hereafter referred to as a holding brake, applied directly to the motor shaft or some part of the gear train.
Each independent hoisting unit of a crane, except worm-geared hoists, the angle of whose worm is such as to prevent the load from accelerating in the lowering direction shall, in addition to a holding brake, be equipped with control braking means to prevent overspeeding.

Holding brakes

Holding brakes for hoist motors shall have not less than the following percentage of the full load hoisting torque at the point where the brake is applied.
125 percent when used with a control braking means other than mechanical.
100 percent when used in conjunction with a mechanical control braking means.
100 percent each if two holding brakes are provided.
Holding brakes on hoists shall have ample thermal capacity for the frequency of operation required by the service.
Holding brakes on hoists shall be applied automatically when power is removed.
Where necessary holding brakes shall be provided with adjustment means to compensate for wear.
The wearing surface of all holding-brake drums or discs shall be smooth.
Each independent hoisting unit of a crane handling hot metal and having power control braking means shall be equipped with at least two holding brakes.

Control braking means

A power control braking means such as regenerative, dynamic or countertorque braking, or a mechanically controlled braking means shall be capable of maintaining safe lowering speeds of rated loads.
The control braking means shall have ample thermal capacity for the frequency of operation required by service.

Brakes for trolleys and bridges

Foot-operated brakes shall not require an applied force of more than 70 pounds to develop manufacturer's rated brake torque.
Brakes may be applied by mechanical, electrical, pneumatic, hydraulic, or gravity means.
Where necessary brakes shall be provided with adjustment means to compensate for wear.
The wearing surface of all brakedrums or discs shall be smooth.
All foot-brake pedals shall be constructed so that the operator's foot will not easily slip off the pedal.
Foot-operated brakes shall be equipped with automatic means for positive release when pressure is released from the pedal.
Brakes for stopping the motion of the trolley or bridge shall be of sufficient size to stop the trolley or bridge within a distance in feet equal to 10 percent of full load speed in feet per minute when traveling at full speed with full load.
If holding brakes are provided on the bridge or trolleys, they shall not prohibit the use of a drift point in the control circuit.
Brakes on trolleys and bridges shall have ample thermal capacity for the frequency of operation required by the service to prevent impairment of functions from overheating.

Application of trolley brakes

On cab-operated cranes with cab on trolley, a trolley brake shall be required as specified under paragraph (f)(4) of this section.
A drag brake may be applied to hold the trolley in a desired position on the bridge and to eliminate creep with the power off.

Application of bridge brakes

On cab-operated cranes with cab on bridge, a bridge brake is required as specified under paragraph (f)(4) of this section.
On cab-operated cranes with cab on trolley, a bridge brake of the holding type shall be required.
On all floor, remote and pulpit-operated crane bridge drives, a brake of noncoasting mechanical drive shall be provided.