Mechanical
(33) Mechanical means a method of control by friction. (34) Controller, spring return means a controller which when released will return automatically to a neutral position. (35) Designated means selected or assigned by the employer or the employer's representative as being qualified to perform specific duties. (36) A drift point means a point on a travel motion controller which releases the brake while the motor is not energized. This allows for coasting before the brake is set. (37) The drum is the cylindrical member around which the ropes are wound for raising or lowering the load. (38) An equalizer is a device which compensates for unequal length or stretch of a rope. (39) Exposed means capable of being contacted inadvertently. Applied to hazardous objects not adequately guarded or isolated. (40) Fail-safe means a provision designed to automatically stop or safely control any motion in which a malfunction occurs. (41) Footwalk means the walkway with handrail, attached to the bridge or trolley for access purposes. (42) A hoist is an apparatus which may be a part of a crane, exerting a force for lifting or lowering. (43) Hoist chain means the load bearing chain in a hoist. (44) Hoist motion means that motion of a crane which raises and lowers a load. (45) Load means the total superimposed weight on the load block or hook. (46) The load block is the assembly of hook or shackle, swivel, bearing, sheaves, pins, and frame suspended by the hoisting rope. (47) Magnet means an electromagnetic device carried on a crane hook to pick up loads magnetically. (48) Main hoist means the hoist mechanism provided for lifting the maximum rated load. (49) A man trolley is a trolley having an operator's cab attached thereto. (50) Rated load means the maximum load for which a crane or individual hoist is designed and built by the manufacturer and shown on the equipment nameplate(s). (51) Rope refers to wire rope, unless otherwise specified. (52) Running sheave means a sheave which rotates as the load block is raised or lowered. (53) Runway means an assembly of rails, beams, girders, brackets, and framework on which the crane or trolley travels. (54) Side pull means that portion of the hoist pull acting horizontally when the hoist lines are not operated vertically. (55) Span means the horizontal distance center to center of runway rails. (56) Standby crane means a crane which is not in regular service but which is used occasionally or intermittently as required. (57) A stop is a device to limit travel of a trolley or crane bridge. This device normally is attached to a fixed structure and normally does not have energy absorbing ability. (58) A switch is a device for making, breaking, or for changing the connections in an electric circuit. (59) An emergency stop switch is a manually or automatically operated electric switch to cut off electric power independently of the regular operating controls. (60) A limit switch is a switch which is operated by some part or motion of a power-driven machine or equipment to alter the electric circuit associated with the machine or equipment. (61) A main switch is a switch controlling the entire power supply to the crane. (62) A master switch is a switch which dominates the operation of contactors, relays, or other remotely operated devices. (63) The trolley is the unit which travels on the bridge rails and carries the hoisting mechanism. (64) Trolley travel means the trolley movement at right angles to the crane runway. (65) Truck means the unit consisting of a frame, wheels, bearings, and axles which supports the bridge girders or trolleys.