Dearborn Overhead Crane Glossary

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Abnormal operating conditions	General	Environmental conditions that are unfavorable, harmful, or detrimental to or for the operation of a crane, such as excessively high or low ambient temperatures, exposure to adverse weather, corrosive fumes, dust-laden or moisture-laden atmospheres, and hazardous locations. (ASME B30.2-1990)
Access platform	Overhead Crane	A limited length platform, located on the idler girder to access to the endtruck wheels only.
Adjustable or variable voltage	Bridge Crane Control	A method of Bridge Crane Control by which the motor supply voltage can be adjusted. (CMAA Spec. 70)
Administrative or regulatory authority	Regulatory	Governmental agency or, in the absence of governmental jurisdiction, the employer. (ASME B30.2-1990)
Ambient temperature	General	The temperature of the atmosphere surrounding the hoist. (ASME HST-4M-1991)
Ampacity	Bridge Crane Bridge Crane Electrical	The current carrying capacity expressed in amperes. (ANSI MH 27.1-1981)
Appointed	Regulatory	Assigned specific responsibilities by the employer or the employer’s representative. (ASME B30-17)
Authorized	Regulatory	Appointed by a duly constituted administrative or regulatory authority. (ASME B30-17)
Automatic crane	Overhead Crane	A crane which when activated operates through a preset cycle or cycles. (ANSI MH 27.1-1981)
Automatic dispatch carrier	Monorail	A carrier which when activated operates through a preset cycle or cycles. (ANSI MH 27.1-1981)
Auxiliary hoist	Hoist	A supplemental hoisting unit, usually designed to handle lighter loads at a higher sped than the main host. (CMAA Spec. 70)
Axle, fixed	Drive	A shaft which is fixed in the end truck and about which the wheel revolves. (WCH)
Axle, rotating	Drive	A shaft which is fixed in the wheel and which rotates on bearings fixed in the end truck. (WCH)
B-10 bearing life	General	The B-lO bearing life of an anti-friction bearing is the minimum expected life, in hours, of 9O~7o of a group of bearings which are operated at a given speed and loading. (ANSI MH 27.1-1981)
Base or deck mounted (hoist)	Hoist	A type of mounting where the hoist is mounted to the top side of a horizontal supporting surface. (ASME HST-4M-1991)
Battery system (backup)	Below Hook Device	Batteries used to guard against inadvertent load release due to loss of primary power to magnet system. (ASME B30.20-1985)
Beam	Overhead Crane & Hoist	An overhead standard structural or specially fabricated shape on which the trolley operates. (ASME HST-4M-1991)
Bearing life	General	The L-10 life of an anti-friction bearing is the minimum expected life, hours, of 90 percent of a group of bearings which are operating-at a given speed and loading. The average expected life of the bearings is approximately five times the L-10 life. (CMAA Spec. 70)
Bearing, lifetime lubricated	General	An antifriction bearing which is provided with seals and a high-stability oxidation-resistant grease to permit operation of the bearing without re-lubrication for not less than the specified B-10 life.
Below the hook device
BHN	General	Brinell hardness number, measurement of material hardness. (CMAA Spec. 70)
Block, load	Hoist	The assembly of hook, swivel, bearings, sheaves, pins and frame suspended from the hoisting ropes. In a “short type” block, the hook and the sheaves are mounted on the same member, called the swivel. In a “long type” block, the hook and the sheaves are mounted on separate members. (The supporting member for the sheaves is called the sheave pin and the supporting member for the hook is called the trunnion. (WCH)
Block, upper	Hoist	A fixed assembly of sheaves, bearings, pins and frame, located on the trolley cross members, and which supports the load block and its load by means of the ropes. (WCH)
Bogie	Overhead Crane	A short end truck attached to the end of one girder (or to a connecting member if more than one bogie is used per girder). This type of end truck is used when more than four wheels are required on a crane due to the design of the runway. (WCH)
Bogie, equalizing	Hoist	A short end truck which is flexibly connected to one girder (or connecting member) by means of a pin upon which the truck can oscillate to equalize the loading on the two truck wheels. This construction uses a very rigid end tie between the girders. (WCH)
Bogie, fixed	Overhead Crane	A short end truck which is rigidly connected to one girder. A flexible end tie is used between the girders to permit equalization of the wheel loads by torsional deflection of the girders and flexing of the end tie. (WCH)
Boom (of gantry cranes)	Overhead Crane	An extension of the trolley runway that may be raised or retracted to obtain clearance for gantry travel. (ASME B30.2-1990)
Boom (of overhead cranes)	Overhead Crane	A horizontal member mounted on the trolley to permit hoisting and lowering the load at a point other than directly under the hoist drum or trolley. (ASME B30.2-1990)
Box section	Overhead Crane	The rectangular cross section of girders, trucks or other members enclosed on four sides. (CMAA Spec. 70)
Brake	Overhead Crane & Hoist	A device, other than a motor, used for retarding or stopping motion by friction or power means. (CMAA Spec. 70)
Brake, Bridge Crane Control	Overhead Crane & Hoist	A method of Bridge Crane Controlling speed by removing energy from the moving body or by imparting energy in the opposite direction. (ASME B30-16-1993)
Brake, countertorque (plugging)	Hoist	A method of Bridge Crane Control by which the power to the motor is reversed to develop torque in the direction opposite to the rotation of the motor using the motor as a generator, with the energy being dissipated by resistance. (ASME B30-16-1993)
Brake, drag	Overhead Crane & Hoist	A friction brake that provides a continuous retarding force having no external Bridge Crane Control. (ASME B30-17)
Brake, dynamic	Hoist	A method of Bridge Crane Controlling speed by block, load the assembly of hook or shackle, swivel. bearing, sheaves, sprockets. pins, and frame suspended by the hoisting rope or load chain. This shall include any appurtenances reeved in the hoisting rope or load chain. (ASME B30-16-1993)
Brake, eddy current	Overhead Crane & Hoist	A method of Bridge Crane Controlling or reducing speed by means of an Bridge Crane Electrical induction load brake. (ASME B30-17)
Brake, emergency	Overhead Crane	A method of decelerating a drive when power is not available. The braking effort may be established as a result of action by the operator, or automatically when power to the drive is interrupted.(ASME B30-17)
Brake, holding	Overhead Crane & Hoist	A friction brake for a hoist that is automatically applied and prevents motion when power to the brake is off. (ASME B30.2-1990)
Brake, hydraulic	Overhead Crane	A method of Bridge Crane Controlling or reducing speed by means of displacement of a liquid. (ASME B30-17)
Brake, mechanical	Overhead Crane & Hoist	A method of Bridge Crane Controlling or reducing speed by friction. (ASME B30-17)
Brake, mechanical load	Hoist	An automatic type of friction brake used for Bridge Crane Controlling loads in a lowering direction. This unidirectional device requires torque from the motor or hand chain wheel to lower a load but does not impose any additional load on the motor or hand chain wheel when lifting a load. (ASME B30-16-1993)
Brake, parking	Overhead Crane	A brake for bridge and trolley that may be automatically or manually applied to impede horizontal motion by restraining wheel rotation. (ASME B30-17)
Brake, pneumatic	Overhead Crane	A method of Bridge Crane Controlling or powering a drive or brake by means of compressed gas. (ASME B30-17)
Brake, regenerative	Hoist	A method of Bridge Crane Controlling speed in which the electrical energy generated by the motor is fed back into the power system. (ASME B30-17)
Brake, service	Overhead Crane	A brake for bridge or trolley used by the operator, during normal operation, to apply a retarding force. (ASME B30.2-1990)
Branch circuit	Bridge Crane Control	The circuit conductors between the final overcurrent device protecting the circuit and the outlet(s). (CMAA Spec. 70)
Breakaway force	Below Hook Device	The external force that is required to separate the vacuum pad or vacuum lifting device from the load when applied perpendicular to the attachment surface. (ASME B30.20-1985)
Bridge	Overhead Crane	That part of an overhead crane consisting of girders, trucks, end ties, walkway and drive mechanism which carries the trolley and travels in a direction parallel to the runway. (CMAA Spec. 70)
Bridge (crane) travel	Overhead Crane	Crane movement in a direction parallel to the crane runway. (ASME B30.11-1993)
Bridge conductors	Overhead Crane	The electrical conductors located along the bridge structure of a crane to provide power to the trolley. (CMAA Spec. 70)
Bridge crane, top running	Overhead Crane
Bridge Crane, Under running	Overhead Crane
Bridge girder (crane girder)	Overhead Crane	Crane member on which carriers or trolleys travel, horizontally mounted between and supported by the end trucks. Building Structure. The structural members of a building which support the building loads and on which the loads of crane or monorail equipment, and the material to be moved, will be imposed. (ANSI MH 27.1-1981)
Bridge rail	Overhead Crane	The rail supported by the bridge girders on which the trolley travels. (CMAA Spec. 70)
Bridge travel	Overhead Crane	The crane movement in a direction parallel to the crane runway. (ASME B30.2-1990)
Bumper (buffer)	Overhead Crane	An energy absorbing 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. (CMAA Spec. 70)
Cab	Overhead Crane	The operator’s compartment on a crane. (ASME B30-17)
Cab Bridge Crane Controlled		Equipment Bridge Crane Controlled from an operator’s cab. (ANSI MH 27.1-1981)
Cab, normal	Overhead Crane	Operator’s compartment used for Bridge Crane Controlling a cab-operated crane. (ASME B30.2-1990)
Cab, skeleton	Overhead Crane	Operator’s compartment used for occasional cab operation of, normally, a floor- or remote-operated crane or carrier. (ASME B30.11-1993)
Cab-operated crane	Overhead Crane	A crane Bridge Crane Controlled by an operator in a cab located on the bridge or trolley. (CMAA Spec. 70)
Camber	Overhead Crane	The slight upward vertical curve given to girders to compensate partially for deflection due to hook load and weight of the Crane. (CMAA Spec. 70)
Cantilever frame	Overhead Crane	A structural member that supports the trolley of a wall crane. (ASME B30.2-1990)
Capacity	General	The maximum rated load (in tons) which a cranes designed. to handle. (CMAA Spec. 70)
Carrier (also known as trolley)	Hoist	A unit that travels on the bottom flange of a monorail track, jib boom, or bridge girder to transport a load. (ASME B30.11-1993)
Carrier (trolley)	Overhead Crane & Hoist	An assembly with wheels which will run on monorail track or crane girders and which will support a load. (ANSI MH 27.1-1981)
Carrier head	Overhead Crane & Hoist	A 2-wheel assembly used with load bars to form a carrier or end truck. (ANSI MH 27.1-1981)
Ceiling mounted	Hoist	A type of hoist mounting where the hoist is mounted to the underside of a horizontal supporting surface. (ASME HST-4M-1991)
Chain, hand	Hoist	The chain grasped by the operator to apply force required for lifting, lowering, or traveling motions. (ASME B30-17)
Chain, load	Hoist	The load-bearing chain in a hoist. (ASME B30-17)
Chain, roller	Hoist	A series of alternately assembled roller links and pin links in which the pins articulate inside the bushings and the rollers are free to turn on the bushings. Pins and bushings are press fit in their respective link plates. . (ASME B30-16-1993)
Chain, welded link	Hoist	A chain consisting of a series of interwoven links fanned and welded. (ASME B30-16-1993)
Circuit breaker	Bridge Crane Electrical	A device to open and close a circuit by non-automatic means, and to open the circuit automatically on a predetermined overload of current, without injury to itself when properly applied within its rating. (ANSI MH 27.1-1981)
Clamp	Monorail	A type of suspension fitting used to support tracks from an overhead structure fastened to the structure by means of pressure rather than welding or direct bolting. (ANSI MH 27.1-1981)
Clearance	General	Minimum distance from the extremity of a crane to the nearest obstruction. (CMAA Spec. 70)
CMAA	Overhead Crane	Crane Manufacturers Association of America, Inc. (formerly EQOI—Electric Overhead Crane Institute). (CMAA Spec. 70)
Cold current	Below hook device	The current drawn by the magnet when its coil is at 68⁰F (20⁰C) and at rated voltage. (ASME B30.20-1985)
Cold current	Below hook device	That current drawn by the magnet when its coil is at 68⁰F (20⁰C) and at rated voltage. (ASME B30.20-1985)
Collector, shoe	Bridge Crane Electrical	The portion of a collector which makes contact by sliding on the conductor bar. (ANSI MH 27.1-1981)
Collector, wheel	Bridge Crane Electrical	The portion of a collector which makes contact by rolling on the conductor bar. (ANSI MH 27.1-1981)
Collectors	Bridge Crane Electrical	Contacting devices for collecting current from the runway or bridge conductors. The mainline collectors are mounted on the bridge to transmit current from the runway conductors, and the trolley collectors are mounted on the trolley to transmit current from the bridge conductors. (CMAA Spec. 70)
Collectors	Bridge Crane Electrical	Electrical contacting devices providing a path for current flow from stationary conductors to moving equipment. (ANSI MH 27.1-1981)
Collectors, current	Bridge Crane Electrical	Contacting devices for collecting current from runway or bridge conductors. (ASME B30.2-1990)
Conductors, bridge	Overhead Crane	The electrical conductors located along the bridge girder(s) to provide power and Bridge Crane Control circuits to the trolley. (Sometimes incorrectly called trolley conductors). (WCH)
Conductors, enclosed	Bridge Crane Electrical	A bar used to transmit an electrical current, enclosed in a non-conducting material to minimize accidental contact with the conductor. (ANSI MH 27.1-1981)
Conductors, open	Bridge Crane Electrical	A bar used to transmit an electrical current. (ANSI MH 27.1-1981)
Conductors, runway (main)	Bridge Crane Electrical	The electrical conductors located along a crane runway that transmit Bridge Crane Control signals and power to the crane. (ASME B30-17)
Contactor	Bridge Crane Electrical	An electromechanical device for opening and closing an electric power circuit. (ASME HST-4M-1991)
Contactor, magnetic	Bridge Crane Control	An electro-magnetic device for opening and closing an electric power circuit. (CMAA Spec. 70)
Bridge Crane Control actuator	Bridge Crane Electrical	A manual means at the operating station by which hoist Bridge Crane Controls are energized. (ASME HST-4M-1991)
Bridge Crane Control braking means	Overhead Crane & Hoist	A method of Bridge Crane Controlling speed by removing energy from the moving body or by imparting energy in the opposite direction. (ASME HST-4M-1991)
Bridge Crane Control enclosure	Bridge Crane Electrical	The housing containing the electrical Bridge Crane Control component. (ASME HST-4M-1991)
Bridge Crane Control panel	Bridge Crane Electrical	See Bridge Crane Control enclosure.
Bridge Crane Control voltage.	Bridge Crane Electrical	The voltage impressed on the Bridge Crane Control devices. (ANSI MH 27.1-1981)
Bridge Crane Control, multi-speed	Bridge Crane Electrical	A drive Bridge Crane Control system providing more than one speed operation in either direction using multi-speed squirrel cage. motors. (ANSI MH 27.1-1981)
Bridge Crane Control, single speed	Bridge Crane Electrical	A drive Bridge Crane Control system providing one speed operation in either direction. (ANSI MH 27.1-1981)
Bridge Crane Control, variable speed	Bridge Crane Electrical	A drive Bridge Crane Control system providing more than one speed operation in either direction using wound-rotor motors.
Bridge Crane Controller	Bridge Crane Control	A device for regulating in a pre-determined way the power delivered to the motor or other equipment. (CMAA Spec. 70)
Bridge Crane Controller, manual	Bridge Crane Control	A Bridge Crane Controller having all of its basic functions performed by devices which are operated by hand. (ASME B30-17)
Bridge Crane Controller, spring return	Bridge Crane Control	A Bridge Crane Controller that, when released, will return automatically to a neutral (off) positioning, 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 Bridge Crane Control, automatic program Bridge Crane Control, or other similar device. (ASME B30.2-1990)
Countertorque	Bridge Crane Control	A method of Bridge Crane Controlling speed by applying a variable motor torque in the direction opposite to the direction that the motor is rotating due to being overhauled by the load. (ASME HST-4M-1991)
Couplings (splices)		Mechanical devices used to join the adjacent ends of track sections. (ANSI MH 27.1-1981)
Cover plate	Overhead Crane	The top or bottom plate of a box girder. (CMAA Spec. 70)
Crane		A machine for lifting, lowering, and moving a load with the hoisting mechanism a part of the machine. Cranes may be traveling, portable, or fixed type. Traveling Cranes. Cranes that follow a fixed path Underhung Crane. A traveling crane with a movable bridge running on the lower flanges of an overhead fixed runway structure and carrying a movable or fixed hoisting mechanism. (ANSI MH 27.1-1981)
Crane girder	Bridge Crane	See Bridge Girder. (ANSI MH 27.1-1981)
Crane service, heavy	Bridge Crane	Service that involves operating at 85 to 100% of rated load or in excess of 10 lift cycles/hr as a regular specified procedure. (ASME B30.2-1990)
Crane service, normal	Bridge Crane	Service that involves operating at less than 85% of rated load and not more than 10 lift cycles/hr except for isolated instances. (ASME B30.2-1990)
Crane service, normal	Bridge Crane	That service which involves operation with randomly distributed loads within the rated load limit, or with uniform loads of less than 65% of the rated load, for no more than 15% of the time of a single work shift for manually operated cranes and 25% of the time of a single work shift for electrically or pneumatically powered cranes. (ASME B30-17)
Crane service, severe	Bridge Crane	Service that involves normal or heavy service with abnormal operating conditions. (ASME B30.2-1990)
Crane, automatic	Bridge Crane	A crane which when activated operates through a preset cycle or cycles. (ASME B30-17)
Crane, cab-operated	Bridge Crane	A crane Bridge Crane Controlled by an operator in a cab attached to the bridge or trolley (refer to Fig. 1). (ASME B30-17)
Crane, cantilever gantry	Bridge Crane	A gantry or semigantry crane in which the bridge girders or trusses extend transversely beyond the crane runway on one or both sides (refer to Fig. 2). (ASME B30-17)
Crane, floor-operated	Bridge Crane	A crane that is Bridge Crane Controlled by a means suspended from the crane, operated by a person on the floor or on an independent platform (refer to Fig. 3) (ASME B30-17)
Crane, gantry	Bridge Crane	A crane similar to an overhead crane, except that the bridge for carrying the trolley or trolleys is rigidly supported on two or more legs running on fixed rails or other runway (refer to Fig. 4). (ASME B30-17)
Crane, hot molten material-handling	Bridge Crane	An overhead crane used for transporting or pouring molten material. (ASME B30-17)
Crane, manually operated	Bridge Crane	A crane whose hoist mechanism is driven by pulling an endless chain, or whose travel mechanism is driven in the same manner or by manually moving the load or hook. (ASME B30.2-1990)
Crane, outdoor storage gantry	Bridge Crane	A gantry-type crane of long span usually used for storage of bulk material such as ore, coal, or other similar items; the bridge girders or trusses are rigidly or nonrigidly supported on one or more legs. It may have one or more fixed or hinged cantilever ends. . (ASME B30.2-1990)
Crane, overhead	Bridge Crane	A crane with a single or multiple girder movable bridge crane a movable or fixed hoisting mechanism and traveling on an overhead fixed runway structure. (ASME B30.2-1990)
Crane, polar	Bridge Crane	An overhead or gantry crane that travels on a circular runway. (ASME B30.2-1990)
Crane, pulpit-operated	Bridge Crane	A crane operated from a fixed operator station not attached to the crane. (ASME B30-17)
Crane, remote-operated	Bridge Crane	A crane Bridge Crane Controlled by an operator who is not in a pulpit or in a cab attached to the crane, by any method other than a means suspended from the crane. (ASME B30-17)
Crane, semi-gantry	Bridge Crane	A gantry with one end of the bridge rigidly supported on one or more legs that run on a fixed rail or runway, the other end of the bridge being supported by an end truck running on an elevated rail or runway. (ASME B30.2-1990)
Crane, single-girder	Bridge Crane	A crane having one bridge girder mounted between, and supported from, the end trucks. (ASME B30.11-1993)
Crane, standby	Bridge Crane	A crane which is not in regular service but which is used occasionally or intermittently as required. (ASME B30-17)
Crane, wall	Bridge Crane	A crane having a cantilever frame with or without trolley, and supported from a side wall or line of columns of a building. It is a traveling type and operates on a runway attached to the side wall or columns. (ASME B30.2-1990)
Cranes, fixed	Bridge Crane	Cranes which are non-mobile. Derricks and jib cranes are classified as fixed cranes. (ANSI MH 27.1-1981)
Cranes, portable	Bridge Crane	Cranes having a revolving superstructure with power plant, operating machinery and boom mounted on a fully mobile carriage not confined to a fixed path. Crawler, locomotive and truck cranes are classified as portable cranes.
Creep speed	Bridge Crane Control	A very slow, constant, continuous, fixed rate of motion of the hoist, trolley, or bridge: usually established at 1% to 10% of the normal full load speed. (WCH)
Cross shaft	Crane	The shaft extending across the bridge, used to transmit torque from motor to bridge drive wheels. (CMAA Spec. 70)
Crossover. (fixed transfer section)	Monorail	A connecting track with an interlock mechanism on both ends, mounted between two interlocking cranes, used to transfer a carrier from one bridge to the other. (ANSI MH 27.1-1981)
Crosstrack switch	Monarail	A track switch containing one straight section of moving track pivoted in the center which can be rotated to align it with other crossing tracks to allow passage of a carrier through the junction without changing the direction of the carrier motion. (ANSI MH 27.1-1981)
Curves	Monorail	Formed sections of monorail track used to change the horizontal or vertical direction of carrier travel. (ANSI MH 27.1-1981)
Cushioned start	Bridge Crane Control	An electrical or mechanical method for reducing the rate of acceleration of a travel motion. (CMAA Spec. 70)
Cushioned start	Bridge Crane Control	An electrical or mechanical method for reducing the rate of acceleration of trolley motion. (ASME HST-4M-1991)
Dead loads	General	The loads on a structure which remain in a fixed position relative to the structure. On a crane bridge such loads include the girders, footwalk, cross shaft, drive units, panels, etc. (CMAA Spec. 70)
Deflection	Bridge Crane	Displacement due to bending or twisting in a vertical or lateral plane, caused by the imposed live and dead loads. (CMAA Spec. 70)
Designated	Regulatory	Selected or assigned by the employer or the employer’s representative as being competent to perform specific duties. (ASME B30.2-1990)
Diaphragm	Bridge Crane	A plate or partition between opposite parts of a member, serving a definite purpose in the structural design of the member. (CMAA Spec. 70)
Disconnecting means	Bridge Crane Electrical	A device, or group of devices, or other means whereby the conductors of a circuit can be disconnected from their power source. (ANSI MH 27.1-1981)
Double girder crane	Bridge Crane	A .crane having two bridge girders mounted between and supported from the end trucks. (ANSI MH 27.1-1981)
Drift point	Bridge Crane & Hoist	A point on a travel motion master switch or on a manual Bridge Crane Controller that maintains the brake released while the motor is not energized. This allows for coasting. (ASME B30.2-1990)
Drive girder	Bridge Crane	The girder on which the bridge drive machinery is mounted. (CMAA Spec. 70)
Driving head.	Bridge Crane & Monorail	A motordriven carrier head which is supported from and propelled by the load bearing wheels. (ANSI MH 27.1-1981)
Drop section (also known as lift section)	Monorail	A mechanism that will permit a section of track(s) to be lifted or lowered out of alignment with the stationary track(s). (ASME B30.11-1993)
Drum	Hoist	The cylindrical member around which rope is wound for lifting or lowering the load. (ASME B30-16-1993)
Dummy cab	Bridge Crane	An operator’s compartment or platform on a pendant or radio Bridge Crane Controlled crane, having no permanently-mounted electrical Bridge Crane Controls, in which an operator may ride while Bridge Crane Controlling the crane. (CMAA Spec. 70)
Dynamic	Bridge Crane Control	A method of Bridge Crane Controlling speed by using the motor as a generator, with the energy being dissipated by resistance. (ASME HST-4M-1991)
Dynamic lowering	Hoist	A method of Bridge Crane Control by which the hoist motor is so connected in the lowering direction, that when it is over-hauled by the load, it acts as a generator and forces current either through the resistors or back into the line. (CMAA Spec. 70)
Eddy current	Bridge Crane Control	See eddy current braking
Eddy-current braking	Bridge Crane Control	A method of Bridge Crane Control by which the motor drives through an electrical induction load brake. (CMAA Spec. 70)
Electric baffle	Bridge Crane Electrical	Conductors that are wired to cut off electric power to approaching motor-driven equipment if track switches, drop sections, and other movable track devices are not properly set for passage of equipment. (ASME B30.11-1993)
Electric overhead traveling crane	Bridge Crane	An electrically operated machine for lifting, lowering and transporting loads, consisting of a movable bridge carrying a fixed or movable hoisting mechanism and traveling on an overhead runway structure. (CMAA Spec. 70)
Electrical braking system	Hoist	A method of Bridge Crane Controlling crane motor speed when in an overhauling condition, without the use of friction braking. (CMAA Spec. 70)
Electrically interlocked	Bridge Crane Control	An electrical device in the starter circuit which prevents a short circuit when opposite Bridge Crane Controls are operated at the same time. (ANSI MH 27.1-1981)
Electrification.	Bridge Crane Electrical	The track mounted conductor system by which the moving equipment receives its electrical power. (ANSI MH 27.1-1981)
Enclosed conductor	Bridge Crane Electrical	A conductor or group of conductors substantially enclosed to prevent accidental contact. (CMAA Spec. 70)
Enclosure	Bridge Crane Electrical	A housing to contain electrical components, usually specified by a NEMA classification number. (CMAA Spec. 70)
End approach	Bridge Crane	The minimum horizontal distance, parallel to the runway, between the outermost extremities of the crane and the centerline of the hook. (CMAA Spec. 70)
End stop	Bridge Crane & Runway	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. (CMAA Spec. 70)
End tie	Bridge Crane	A structural member other than the end truck which connects the ends of the girders to maintain the squareness of the bridge. (CMAA Spec. 70)
End truck	Bridge Crane	An assembly consisting of the frame and wheels which support the crane girder(s) and allow movement along the runway. (ASME B30.11-1993)
End truck loa	Bridge Crane
Equalizer	Hoist	A device which compensates for unequal length or stretch of a rope or chain. (ASME B30-16-1993)
Exposed	Bridge Crane Electrical	Applies to hazardous objects not guarded or isolated (capable of being contacted inadvertently). (ASME B30-17)
Fail-safe	General	A provision designed to automatically stop or safely Bridge Crane Control any motion in which a malfunction occurs. (CMAA Spec. 70)
Field wiring	General	The wiring required after erection of the crane. (CMAA Spec. 70)
Fixed axle	Bridge Crane	An axle which is fixed in the truck and on which the wheel revolves. (CMAA Spec. 70)
Fixed Transfer Section		See Crossover. (ANSI MH 27.1-1981)
Fixed transfer section (also known as crossover)	Monorail	A connecting track with an interlock mechanism on both ends, mounted between two interlocking cranes, used to transfer a carrier from one bridge to the other. (ASME B30.11-1993)
Fleet angle	Hoist	The angle formed by the wire rope and the drum groove or sheave groove in the plane which contains the wire rope and is parallel to the drum or sheave axis. (WCH)
Floor Bridge Crane Controlled	Bridge Crane Control	Motor propelled units which are Bridge Crane Controlled by an operator on the floor by means of pushbutton station suspended from the overhead equipment. (ANSI MH 27.1-1981)
Foot walk	Bridge Crane	The full length walkway with handrail and toeboards, attached to the bridge or trolley for access purposes. Not to be confused with an access platform (usually a short platform provided only to access endtruck).
Force, breakaway	Below hook device	— the force that must be applied to a magnet to remove it from a piece of ferromagnetic material to which it is magnetically attached. (ASME B30.20-1985)
Fork	Below hook device	A mechanical device for use on interlocking transfer equipment to mechanically prevent passage. (ANSI MH 27.1-1981)
Friction-type pressure gripping lifters	Below hook device	Lifters that grip the load without significant or harmful permanent deformation of the load surface (see Figs. 17 through 21). (ASME B30.20-1985)
Gantry crane	Bridge Crane	A crane similar to an overhead crane except that the bridge for carrying the trolley or trolleys is rigidly supported on two or more legs running on fixed rails or other runway. (CMAA Spec. 70)
Gantry leg	Bridge Crane	The structural member which supports a bridge girder or end tie from the sill. (ASME B30-17)
Gauge	Bridge Crane	The center-to-center distance between the load carrying flanges of the two crane girders of a double girder crane. (ANSI MH 27.1-1981)
Girder, auxiliary (outrigger)	Bridge Crane	An additional girder, either solid or latticed, arranged parallel to the bridge girder(s) for supporting the foot-walk, Bridge Crane Control panels, operator’s cab, etc., to reduce the torsional forces such loads might otherwise impose. (WCH)
Girder, bridge	Bridge Crane	The principal horizontal beam(s) of the crane, which supports the trolley, is supported by the end trucks, and is perpendicular to the runway. (WCH)
Girder, drive (girder “a”)	Bridge Crane	The bridge girder to which the bridge motor and gearcase(s) are attached. For cranes having a drive on each girder, it is the girder to which the Bridge Crane Control panels and/or the cab are attached. (WCH)
Girder, idler (girder “b”)	Bridge Crane	The bridge girder which does not have the bridge drive attached, but which usually carries the bridge conductors. (WCH)
Girder, runway	Bridge Crane	A horizontal beam attached to the building columns or wall, and supporting a runway rail on which the crane travels. (WCH)
Glide switch (sliding switch)	Monorail	A track switch with a movable end frame containing straight and/or curved sections of track. The inner frame can be slid to align these sections of track with other tracks for routing carriers from one track to another. (ANSI MH 27.1-1981)
Grip ratio	Below hook device	The ratio of the sum of the horizontal forces on one side of the load to the live weight of the load. For example, if the total horizontal force on one side of the load is 100,000 lb. and the live load is 50,000 lb. the grip ratio is 2. For purposes of this calculation, the weight of the load does not include the weight of the lifter (see Fig. I). (ASME B30.20-1985)
Gripping force	Below hook device	The force the lifting device exerts on the load. (ASME B30.20-1985)
Ground fault	Bridge Crane Electrical	An accidental conducting connection between the electrical circuit or equipment and the earth or some conducting body that serves in place of the earth. (CMAA Spec. 70)
Guide, chain	Hoist	A means to guide the load chain at the load sprocket. (ASME B30-16-1993)
Hand chain	Hoist	The chain provided to Bridge Crane Control movement of a hand chain operated trolley. (ASME HST-4M-1991)
Hanger rod	Monorail	A steel rod which, together with other fittings, is used to suspend the track from the supporting structure. (ASME B30.11-1993)
Hanger rod.	Bridge Crane & Monorail	Steel rods which, together with other fittings, are used to suspend the track from the supporting structure. (ANSI MH 27.1-1981)
Hazardous (classified) locations	Regulatory	Locations where fire or explosion hazards may exist. Locations are classified depending on the properties of the flammable vapors, liquids or gases. or combustible dusts or fibers which may be present and the likelihood that a flammable or combustible concentration or quantity is present. Refer to ANSI/NFPA 70. — Class I locations — Locations in which flammable gases or vapors are or may be present in the air in quantities sufficient to produce explosive or ignitable mixtures — Class 2 locations — Locations that are hazardous because of the presence of combustible dust — Class 3 locations — Locations that are hazardous because of the presence of easily ignitable fibers or filings, but in which such fibers or filings are not likely to be in suspension in the air in quantities sufficient to produce ignitable mixtures. (ASME B30-16-1993)
Headroom	Hoist	Headroom is measured with the load hook at its upper limit of travel and is the distance from the saddle of the load hook to the following locations (see Fig. 1) — (a) centerline of the suspension holes on lug suspended hoists [see Fig. 1, sketch (a)]; — (b) saddle of the top hook on hook suspended hoists [see Fig. 1, sketch (b)]; — (c) bottom of the beam on trolley suspended hoists [see Fig. 1, sketch (c)]; — (d) supporting surface on base and deck mounted hoists [see Fig. 1, sketch (d)]; — (e) uppermost point of hoist on wall and ceiling mounted hoists [see Fig. 1, sketches (e) and (f)]. . (ASME HST-4M-1991)
High temperature service	General	A condition where the surface to which the vacuum pad (or pads) is attached is above 250⁰F (120⁰C). (ASME B30.20-1985)
Hoist	Hoist	A suspended machinery unit which is used for lifting or lowering a freely suspended (unguided) load. (ASME HST-4M-1991)
Hoist motion	Hoist	That motion which lifts or lowers a load. (ASME B30-17)
Hoist speed	Hoist	Hoist speed is the rate of motion that the load hook attains while lifting rated load.
Hoist, auxiliary	Hoist	A supplemental hoisting unit, usually of lower load rating and higher speed than the main hoist. (ASME B30-17)
Hoist, main	Hoist	The primary hoist mechanism provided for lifting and lowering the rated load of the crane. (WCH)
Holding brake	Hoist	A friction brake for a hoist which is automatically applied and prevents motion when power is off. (ASME HST-4M-1991)
Hook approach	Bridge Crane & Hoist	The minimum horizontal distance between the center of the runway rail and the hook. (CMAA Spec. 70)
Hook approach, end	Bridge Crane & Hoist	The minimum horizontal distance, parallel to the runway, between the centerline of the hook(s) and the face of the wall (or columns) at the end of the building. (WCH)
Hook approach, side	Bridge Crane & Hoist	The minimum horizontal distance, perpendicular to the runway, between the centerline of a hook (main or auxiliary) and the centerline of the runway rail. (WCH)
Hook suspended	Hoist	Suspension of hoist from a trolley or rigid structure by means of a hook(s) at top of hoist. (ASME HST-4M-1991)
Hook to hook approach	Bridge Crane
Hook; latch type	Hoist	A type of hook with a mechanical device to bridge the throat opening of the hook. (ASME HST-4M-1991)