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Definitions

 

braking, pneumatic

crane, cantilever gantry


braking, pneumatic: a method of controlling or reducing speed by means of compressed gas.

braking, regenerative: a method of controlling speed in which the electrical energy generated by the motor is fed back into the power system.

braking, service: a method to decelerate crane motion during normal operation.

bridge: that part of a crane consisting of one or more girders, trucks, end ties, foot walks, and drive mechanism, which carries the trolley or trolleys.

bridge travel: the crane movement in a direction parallel to the crane runway.

bumper (buffer): a device for reducing impact when a moving crane or trolley reaches the end of its permitted travel, or when two moving cranes or trolleys come into contact. This device may be attached to the bridge, trolley, or runway stop.

cab: the operator's compartment used for controlling crane,

cab, normal: operator’s compartment used for controlling a cab-operated crane.

cab, skeleton: operator’s compartment used for occasional cab operation of a normally floor- or remote-operated crane.

cantilever frame: a structural member that supports the trolley of a wall crane,

clearance: distance from any part of the crane to the nearest obstruction.

collectors, current: contacting devices for collecting current from runway or bridge conductors.

conductors, bridge: the electrical conductors located along the bridge structure of a crane that transmit control signals and power to the trolley(s).

conductors, runway (main): the electrical conductors located along a crane runway that transmit control signals and power to the crane.

controller: a device or group of devices that serves to govern, in a predetermined manner, the power delivered directly to the apparatus to which it is connected.

controller, manual: a controller having all of its basic functions performed by devices that are operated by hand.

controller spring return: a controller that, when released, will return automatically to a neutral (off) position.



Fig. 1  Cantilever Gantry Crane
 

control panel: an assembly of components (magnetic, static, hydraulic, pneumatic, etc.) that governs the flow of power to or from a motor or other equipment in response to signals from a master switch, push-button station, remote control, automatic program, or other similar device.

crane: a machine for lifting and lowering a load and moving it horizontally, with the hoisting: mechanism being an integral part of the machine.

crane, automatic: a crane which, when activated, operates through a preset cycle or cycles.

crane, cab operated: a crane whose movements are controlled by an operator through the use of controllers located in a cab that is attached to the crane.

crane, cantilever gantry: a gantry or semigantry crane in which the bridge girders or trusses extend transversely beyond the crane runway on one or both sides (see Fig. 1).