Glossary a E

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    Abnormal operatingconditions

    General Environmental conditions that are unfavorable,harmful, or detrimental to or for the operation of acrane, such as excessively high or low ambienttemperatures, exposure to adverse weather,corrosive fumes, dust-laden or moisture-laden

    atmospheres, and hazardous locations. (ASMEB30.2-1990)

    Access platform OverheadCrane

    A limited length platform, located on the idlergirder to access to the endtruck wheels only.

    Adjustable or variablevoltage

    BridgeCraneControl

    A method of Bridge Crane Control by which themotor supply voltage can be adjusted. (CMAASpec. 70)

    Administrative orregulatory authority

    Regulatory Governmental agency or, in the absence ofgovernmental jurisdiction, the employer. (ASMEB30.2-1990)

    Ambient temperature General The temperature of the atmosphere surrounding

    the hoist. (ASME HST-4M-1991)Ampacity Bridge

    CraneBridgeCraneElectrical

    The current carrying capacity expressed inamperes. (ANSI MH 27.1-1981)

    Appointed Regulatory Assigned specific responsibilities by theemployer or the employers representative.(ASME B30-17)

    Authorized Regulatory Appointed by a duly constituted administrative orregulatory authority. (ASME B30-17)

    Automatic crane

    OverheadCrane

    A crane which when activated operates througha preset cycle or cycles. (ANSI MH 27.1-1981)

    Automatic dispatchcarrier

    Monorail A carrier which when activated operates througha preset cycle or cycles. (ANSI MH 27.1-1981)

    Auxiliary hoist Hoist A supplemental hoisting unit, usually designed tohandle lighter loads at a higher sped than themain host. (CMAA Spec. 70)

    Axle, fixed Drive A shaft which is fixed in the end truck and aboutwhich the wheel revolves. (WCH)

    Axle, rotating Drive A shaft which is fixed in the wheel and whichrotates on bearings fixed in the end truck. (WCH)

    B-10 bearing life

    General

    The B-lO bearing life of an anti-friction bearing isthe minimum expected life, in hours, of 9O~7o ofa group of bearings which are operated at agiven speed and loading. (ANSI MH 27.1-1981)

    Base or deck mounted(hoist)

    Hoist A type of mounting where the hoist is mounted tothe top side of a horizontal supporting surface.(ASME HST-4M-1991)

    Battery system Below Batteries used to guard against inadvertent load

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    (backup) HookDevice

    release due to loss of primary power to magnetsystem. (ASME B30.20-1985)

    Beam OverheadCrane &Hoist

    An overhead standard structural or speciallyfabricated shape on which the trolley operates.(ASME HST-4M-1991)

    Bearing life

    General

    The L-10 life of an anti-friction bearing is theminimum expected life, hours, of 90 percent of agroup of bearings which are operating-at a givenspeed and loading. The average expected life ofthe bearings is approximately five times the L-10life. (CMAA Spec. 70)

    Bearing, lifetimelubricated

    General An antifriction bearing which is provided withseals and a high-stability oxidation-resistantgrease to permit operation of the bearing withoutre-lubrication for not less than the specified B-10life.

    Below the hook deviceBHN 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 thehoisting ropes. In a short type block, the hookand the sheaves are mounted on the samemember, called the swivel. In a long type block,the hook and the sheaves are mounted onseparate members. (The supporting member forthe sheaves is called the sheave pin and the

    supporting member for the hook is called thetrunnion. (WCH)

    Block, upper Hoist A fixed assembly of sheaves, bearings, pins andframe, located on the trolley cross members, andwhich supports the load block and its load bymeans of the ropes. (WCH)

    Bogie OverheadCrane

    A short end truck attached to the end of onegirder (or to a connecting member if more thanone bogie is used per girder). This type of endtruck is used when more than four wheels arerequired 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 ofa pin upon which the truck can oscillate toequalize the loading on the two truck wheels.This construction uses a very rigid end tiebetween the girders. (WCH)

    Bogie, fixed Overhead A short end truck which is rigidly connected to

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    Crane one girder. A flexible end tie is used between thegirders to permit equalization of the wheel loadsby torsional deflection of the girders and flexingof 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 gantrytravel. (ASME B30.2-1990)

    Boom (of overheadcranes)

    OverheadCrane

    A horizontal member mounted on the trolley topermit hoisting and lowering the load at a pointother than directly under the hoist drum ortrolley. (ASME B30.2-1990)

    Box section OverheadCrane

    The rectangular cross section of girders, trucksor other members enclosed on four sides.(CMAA Spec. 70)

    Brake OverheadCrane &

    Hoist

    A device, other than a motor, used for retardingor stopping motion by friction or power means.

    (CMAA Spec. 70)Brake, Bridge Crane

    ControlOverheadCrane &Hoist

    A method of Bridge Crane Controlling speed byremoving energy from the moving body or byimparting energy in the opposite direction.(ASME B30-16-1993)

    Brake, countertorque(plugging)

    Hoist A method of Bridge Crane Control by which thepower to the motor is reversed to develop torquein the direction opposite to the rotation of themotor using the motor as a generator, with theenergy being dissipated by resistance. (ASMEB30-16-1993)

    Brake, drag

    OverheadCrane &Hoist

    A friction brake that provides a continuousretarding force having no external Bridge CraneControl. (ASME B30-17)

    Brake, dynamic Hoist A method of Bridge Crane Controlling speed byblock, load the assembly of hook or shackle,swivel. bearing, sheaves, sprockets. pins, andframe suspended by the hoisting rope or loadchain. This shall include any appurtenancesreeved in the hoisting rope or load chain. (ASMEB30-16-1993)

    Brake, eddy current Overhead

    Crane &Hoist

    A method of Bridge Crane Controlling or

    reducing speed by means of an Bridge CraneElectrical induction load brake. (ASME B30-17)

    Brake, emergency OverheadCrane

    A method of decelerating a drive when power isnot available. The braking effort may beestablished as a result of action by the operator,or automatically when power to the drive isinterrupted.(ASME B30-17)

    Brake, holding Overhead A friction brake for a hoist that is automatically

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    Crane &Hoist

    applied and prevents motion when power to thebrake is off. (ASME B30.2-1990)

    Brake, hydraulic OverheadCrane

    A method of Bridge Crane Controlling orreducing speed by means of displacement of aliquid. (ASME B30-17)

    Brake, mechanical

    OverheadCrane &Hoist

    A method of Bridge Crane Controlling or reduc-ing speed by friction. (ASME B30-17)

    Brake, mechanical load Hoist An automatic type of friction brake used forBridge Crane Controlling loads in a loweringdirection. This unidirectional device requirestorque from the motor or hand chain wheel tolower a load but does not impose any additionalload on the motor or hand chain wheel whenlifting a load. (ASME B30-16-1993)

    Brake, parking Overhead

    Crane

    A brake for bridge and trolley that may be

    automatically or manually applied to impedehorizontal motion by restraining wheel rotation.(ASME B30-17)

    Brake, pneumatic OverheadCrane

    A method of Bridge Crane Controlling or pow-ering a drive or brake by means of compressedgas. (ASME B30-17)

    Brake, regenerative Hoist A method of Bridge Crane Controlling speed inwhich the electrical energy generated by themotor is fed back into the power system. (ASMEB30-17)

    Brake, service Overhead

    Crane

    A brake for bridge or trolley used by the operator,

    during normal operation, to apply a retardingforce. (ASME B30.2-1990)

    Branch circuit BridgeCraneControl

    The circuit conductors between the finalovercurrent device protecting the circuit and theoutlet(s). (CMAA Spec. 70)

    Breakaway force BelowHookDevice

    The external force that is required to separatethe vacuum pad or vacuum lifting device from theload when applied perpendicular to theattachment surface. (ASME B30.20-1985)

    Bridge OverheadCrane

    That part of an overhead crane consisting ofgirders, trucks, end ties, walkway and drive

    mechanism which carries the trolley and travelsin a direction parallel to the runway. (CMAASpec. 70)

    Bridge (crane) travel OverheadCrane

    Crane movement in a direction parallel to thecrane runway. (ASME B30.11-1993)

    Bridge conductors OverheadCrane

    The electrical conductors located along thebridge structure of a crane to provide power tothe trolley. (CMAA Spec. 70)

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    Bridge crane, toprunning

    OverheadCrane

    Bridge Crane, Underrunning

    OverheadCrane

    Bridge girder (crane

    girder)

    Overhead

    Crane

    Crane member on which carriers or trolleys

    travel, horizontally mounted between andsupported by the end trucks. Building Structure.The structural members of a building whichsupport the building loads and on which theloads of crane or monorail equipment, and thematerial to be moved, will be imposed. (ANSI MH27.1-1981)

    Bridge rail OverheadCrane

    The rail supported by the bridge girders on whichthe trolley travels. (CMAA Spec. 70)

    Bridge travel OverheadCrane

    The crane movement in a direction parallel to thecrane runway. (ASME B30.2-1990)

    Bumper (buffer)

    OverheadCrane

    An energy absorbing device for reducing impactwhen a moving crane or trolley reaches the endof its permitted travel, or when two movingcranes or trolleys come into contact. (CMAASpec. 70)

    Cab OverheadCrane

    The operators compartment on a crane. (ASMEB30-17)

    Cab Bridge CraneControlled

    Equipment Bridge Crane Controlled from anoperators cab. (ANSI MH 27.1-1981)

    Cab, normal OverheadCrane

    Operators compartment used for Bridge CraneControlling a cab-operated crane. (ASME B30.2-

    1990)

    Cab, skeleton OverheadCrane

    Operators compartment used for occasional caboperation of, normally, a floor- or remote-operated crane or carrier. (ASME B30.11-1993)

    Cab-operated crane OverheadCrane

    A crane Bridge Crane Controlled by an operatorin a cab located on the bridge or trolley. (CMAASpec. 70)

    Camber OverheadCrane

    The slight upward vertical curve given to girdersto compensate partially for deflection due to hookload 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 acranes designed. to handle. (CMAA Spec. 70)

    Carrier (also known astrolley)

    Hoist A unit that travels on the bottom flange of amonorail track, jib boom, or bridge girder totransport a load. (ASME B30.11-1993)

    Carrier (trolley) OverheadCrane &

    An assembly with wheels which will run onmonorail track or crane girders and which will

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    Hoist support a load. (ANSI MH 27.1-1981)

    Carrier head OverheadCrane &Hoist

    A 2-wheel assembly used with load bars to forma 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 horizontalsupporting surface. (ASME HST-4M-1991)

    Chain, hand Hoist The chain grasped by the operator to apply forcerequired for lifting, lowering, or travelingmotions. (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 andpin links in which the pins articulate inside thebushings and the rollers are free to turn on thebushings. 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 BridgeCraneElectrical

    A device to open and close a circuit by non-automatic means, and to open the circuitautomatically on a predetermined overload ofcurrent, without injury to itself when properlyapplied within its rating. (ANSI MH 27.1-1981)

    Clamp Monorail A type of suspension fitting used to supporttracks from an overhead structure fastened tothe 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 craneto the nearest obstruction. (CMAA Spec. 70)

    CMAA OverheadCrane

    Crane Manufacturers Association of America,Inc. (formerly EQOIElectric Overhead CraneInstitute). (CMAA Spec. 70)

    Cold current Belowhook

    device

    The current drawn by the magnet when its coil isat 680F (200C) and at rated voltage. (ASMEB30.20-1985)

    Cold current Belowhook

    device

    That current drawn by the magnet when its coil isat 680F (200C) and at rated voltage. (ASME

    B30.20-1985)

    Collector, shoe BridgeCraneElectrical

    The portion of a collector which makes contactby sliding on the conductor bar. (ANSI MH 27.1-1981)

    Collector, wheel BridgeCraneElectrical

    The portion of a collector which makes contactby rolling on the conductor bar. (ANSI MH 27.1-1981)

    Collectors Bridge Contacting devices for collecting current from the

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    CraneElectrical

    runway or bridge conductors. The mainlinecollectors are mounted on the bridge to transmitcurrent from the runway conductors, and thetrolley collectors are mounted on the trolley totransmit current from the bridge conductors.

    (CMAA Spec. 70)

    Collectors BridgeCraneElectrical

    Electrical contacting devices providing a path forcurrent flow from stationary conductors tomoving equipment. (ANSI MH 27.1-1981)

    Collectors, current BridgeCraneElectrical

    Contacting devices for collecting current fromrunway or bridge conductors. (ASME B30.2-1990)

    Conductors, bridge OverheadCrane

    The electrical conductors located along thebridge girder(s) to provide power and BridgeCrane Control circuits to the trolley. (Sometimesincorrectly called trolley conductors). (WCH)

    Conductors, enclosed

    BridgeCraneElectrical

    A bar used to transmit an electrical current,enclosed in a non-conducting material tominimize accidental contact with the conductor.(ANSI MH 27.1-1981)

    Conductors, open BridgeCraneElectrical

    A bar used to transmit an electrical current.(ANSI MH 27.1-1981)

    Conductors, runway(main)

    BridgeCraneElectrical

    The electrical conductors located along a cranerunway that transmit Bridge Crane Controlsignals and power to the crane. (ASME B30-17)

    Contactor Bridge

    CraneElectrical

    An electromechanical device for opening and

    closing an electric power circuit. (ASME HST-4M-1991)

    Contactor, magnetic BridgeCraneControl

    An electro-magnetic device for opening andclosing an electric power circuit. (CMAA Spec.70)

    Bridge Crane Controlactuator

    BridgeCraneElectrical

    A manual means at the operating station bywhich hoist Bridge Crane Controls areenergized. (ASME HST-4M-1991)

    Bridge Crane Controlbraking means

    OverheadCrane &Hoist

    A method of Bridge Crane Controlling speed byremoving energy from the moving body or byimparting energy in the opposite direction.

    (ASME HST-4M-1991)

    Bridge Crane Controlenclosure

    BridgeCraneElectrical

    The housing containing the electrical BridgeCrane Control component. (ASME HST-4M-1991)

    Bridge Crane Controlpanel

    BridgeCraneElectrical

    See Bridge Crane Control enclosure.

    Bridge Crane Control Bridge The voltage impressed on the Bridge Crane

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    voltage. CraneElectrical

    Control devices. (ANSI MH 27.1-1981)

    Bridge Crane Control,multi-speed

    BridgeCraneElectrical

    A drive Bridge Crane Control system providingmore than one speed operation in either directionusing multi-speed squirrel cage. motors. (ANSI

    MH 27.1-1981)Bridge Crane Control,

    single speedBridgeCraneElectrical

    A drive Bridge Crane Control system providingone speed operation in either direction. (ANSIMH 27.1-1981)

    Bridge Crane Control,variable speed

    BridgeCraneElectrical

    A drive Bridge Crane Control system providingmore than one speed operation in either directionusing wound-rotor motors.

    Bridge Crane Controller BridgeCraneControl

    A device for regulating in a pre-determined waythe power delivered to the motor or otherequipment. (CMAA Spec. 70)

    Bridge Crane

    Controller, manual

    Bridge

    CraneControl

    A Bridge Crane Controller having all of its basic

    functions performed by devices which areoperated by hand. (ASME B30-17)

    Bridge CraneController, spring return

    BridgeCraneControl

    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 motoror other equipment in response to signals from amaster switch, push-button station, remoteBridge Crane Control, automatic program BridgeCrane Control, or other similar device. (ASMEB30.2-1990)

    Countertorque

    BridgeCraneControl

    A method of Bridge Crane Controlling speed byapplying a variable motor torque in the directionopposite to the direction that the motor is rotatingdue to being overhauled by the load. (ASMEHST-4M-1991)

    Couplings (splices) Mechanical devices used to join the adjacentends of track sections. (ANSI MH 27.1-1981)

    Cover plate OverheadCrane

    The top or bottom plate of a box girder. (CMAASpec. 70)

    Crane A machine for lifting, lowering, and moving a loadwith the hoisting mechanism a part of the

    machine. Cranes may be traveling, portable, orfixed type.

    Traveling Cranes. Cranes that follow a fixed path

    Underhung Crane. A traveling crane with amovable bridge running on the lower flanges ofan overhead fixed runway structure and carrying

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    a movable or fixed hoisting mechanism. (ANSIMH 27.1-1981)

    Crane girder BridgeCrane

    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 aregular specified procedure. (ASME B30.2-1990)

    Crane service, normal BridgeCrane

    Service that involves operating at less than 85%of rated load and not more than 10 lift cycles/hrexcept for isolated instances. (ASME B30.2-1990)

    Crane service, normal BridgeCrane

    That service which involves operation withrandomly distributed loads within the rated loadlimit, or with uniform loads of less than 65% ofthe rated load, for no more than 15% of the time

    of a single work shift for manually operatedcranes and 25% of the time of a single work shiftfor electrically or pneumatically powered cranes.(ASME B30-17)

    Crane service, severe BridgeCrane

    Service that involves normal or heavy servicewith abnormal operating conditions. (ASMEB30.2-1990)

    Crane, automatic BridgeCrane

    A crane which when activated operates througha preset cycle or cycles. (ASME B30-17)

    Crane, cab-operated BridgeCrane

    A crane Bridge Crane Controlled by an operatorin a cab attached to the bridge or trolley (refer to

    Fig. 1). (ASME B30-17)

    Crane, cantilevergantry

    BridgeCrane

    A gantry or semigantry crane in which the bridgegirders or trusses extend transversely beyondthe crane runway on one or both sides (refer toFig. 2). (ASME B30-17)

    Crane, floor-operated BridgeCrane

    A crane that is Bridge Crane Controlled by ameans suspended from the crane, operated by aperson on the floor or on an independentplatform (refer to Fig. 3) (ASME B30-17)

    Crane, gantry BridgeCrane

    A crane similar to an overhead crane, except thatthe bridge for carrying the trolley or trolleys is

    rigidly supported on two or more legs running onfixed rails or other runway (refer to Fig. 4).(ASME B30-17)

    Crane, hot moltenmaterial-handling

    BridgeCrane

    An overhead crane used for transporting orpouring molten material. (ASME B30-17)

    Crane, manuallyoperated

    BridgeCrane

    A crane whose hoist mechanism is driven bypulling an endless chain, or whose travelmechanism is driven in the same manner or by

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    manually moving the load or hook. (ASMEB30.2-1990)

    Crane, outdoor storagegantry

    BridgeCrane

    A gantry-type crane of long span usually used forstorage of bulk material such as ore, coal, orother similar items; the bridge girders or trusses

    are rigidly or nonrigidly supported on one ormore legs. It may have one or more fixed orhinged cantilever ends. . (ASME B30.2-1990)

    Crane, overhead BridgeCrane

    A crane with a single or multiple girder movablebridge crane a movable or fixed hoistingmechanism and traveling on an overhead fixedrunway structure. (ASME B30.2-1990)

    Crane, polar BridgeCrane

    An overhead or gantry crane that travels on acircular runway. (ASME B30.2-1990)

    Crane, pulpit-operated BridgeCrane

    A crane operated from a fixed operator stationnot attached to the crane. (ASME B30-17)

    Crane, remote-operated

    BridgeCrane

    A crane Bridge Crane Controlled by an operatorwho is not in a pulpit or in a cab attached to thecrane, by any method other than a meanssuspended from the crane. (ASME B30-17)

    Crane, semi-gantry BridgeCrane

    A gantry with one end of the bridge rigidlysupported on one or more legs that run on afixed rail or runway, the other end of the bridgebeing supported by an end truck running on anelevated rail or runway. (ASME B30.2-1990)

    Crane, single-girder BridgeCrane

    A crane having one bridge girder mountedbetween, and supported from, the end trucks.

    (ASME B30.11-1993)

    Crane, standby BridgeCrane

    A crane which is not in regular service but whichis used occasionally or intermittently asrequired. (ASME B30-17)

    Crane, wall BridgeCrane

    A crane having a cantilever frame with or withouttrolley, and supported from a side wall or line ofcolumns of a building. It is a traveling type andoperates on a runway attached to the side wall orcolumns. (ASME B30.2-1990)

    Cranes, fixed BridgeCrane

    Cranes which are non-mobile. Derricks and jibcranes are classified as fixed cranes. (ANSI MH

    27.1-1981)

    Cranes, portable BridgeCrane

    Cranes having a revolving superstructure withpower plant, operating machinery and boommounted on a fully mobile carriage not confinedto a fixed path. Crawler, locomotive and truckcranes are classified as portable cranes.

    Creep speed BridgeCrane

    A very slow, constant, continuous, fixed rate ofmotion of the hoist, trolley, or bridge: usually

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    Control established at 1% to 10% of the normal full loadspeed. (WCH)

    Cross shaft Crane The shaft extending across the bridge, used totransmit torque from motor to bridge drivewheels. (CMAA Spec. 70)

    Crossover. (fixedtransfer section)

    Monorail

    A connecting track with an interlock mechanismon both ends, mounted between two interlockingcranes, used to transfer a carrier from one bridgeto the other. (ANSI MH 27.1-1981)

    Crosstrack switch Monarail A track switch containing one straight section ofmoving track pivoted in the center which can berotated to align it with other crossing tracks toallow passage of a carrier through the junctionwithout changing the direction of the carriermotion. (ANSI MH 27.1-1981)

    Curves Monorail Formed sections of monorail track used to

    change the horizontal or vertical direction ofcarrier travel. (ANSI MH 27.1-1981)

    Cushioned start BridgeCraneControl

    An electrical or mechanical method for reducingthe rate of acceleration of a travel motion.(CMAA Spec. 70)

    Cushioned start BridgeCraneControl

    An electrical or mechanical method for reducingthe rate of acceleration of trolley motion. (ASMEHST-4M-1991)

    Dead loads General The loads on a structure which remain in a fixedposition relative to the structure. On a cranebridge such loads include the girders, footwalk,

    cross shaft, drive units, panels, etc. (CMAASpec. 70)

    Deflection BridgeCrane

    Displacement due to bending or twisting in avertical or lateral plane, caused by the imposedlive and dead loads. (CMAA Spec. 70)

    Designated Regulatory Selected or assigned by the employer or theemployers representative as being competent toperform specific duties. (ASME B30.2-1990)

    Diaphragm BridgeCrane

    A plate or partition between opposite parts of amember, serving a definite purpose in thestructural design of the member. (CMAA Spec.

    70)

    Disconnecting means BridgeCraneElectrical

    A device, or group of devices, or other meanswhereby the conductors of a circuit can bedisconnected from their power source. (ANSI MH27.1-1981)

    Double girder crane BridgeCrane

    A .crane having two bridge girders mountedbetween and supported from the end trucks.(ANSI MH 27.1-1981)

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    Drift point BridgeCrane &Hoist

    A point on a travel motion master switch or on amanual Bridge Crane Controller that maintainsthe brake released while the motor is notenergized. This allows for coasting. (ASMEB30.2-1990)

    Drive girder

    BridgeCrane

    The girder on which the bridge drive machineryis mounted. (CMAA Spec. 70)

    Driving head. BridgeCrane &Monorail

    A motordriven carrier head which is supportedfrom and propelled by the load bearing wheels.(ANSI MH 27.1-1981)

    Drop section (alsoknown as lift section)

    Monorail A mechanism that will permit a section of track(s)to be lifted or lowered out of alignment with thestationary track(s). (ASME B30.11-1993)

    Drum Hoist The cylindrical member around which rope iswound for lifting or lowering the load. (ASMEB30-16-1993)

    Dummy cab

    BridgeCrane

    An operators compartment or platform on apendant or radio Bridge Crane Controlled crane,having no permanently-mounted electrical BridgeCrane Controls, in which an operator may ridewhile Bridge Crane Controlling the crane.(CMAA Spec. 70)

    Dynamic BridgeCraneControl

    A method of Bridge Crane Controlling speed byusing the motor as a generator, with the energybeing 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 loweringdirection, that when it is over-hauled by the load,it acts as a generator and forces current eitherthrough the resistors or back into the line.(CMAA Spec. 70)

    Eddy current BridgeCraneControl

    See eddy current braking

    Eddy-current braking BridgeCraneControl

    A method of Bridge Crane Control by which themotor drives through an electrical induction loadbrake. (CMAA Spec. 70)

    Electric baffle BridgeCraneElectrical

    Conductors that are wired to cut off electricpower to approaching motor-driven equipment iftrack switches, drop sections, and other movabletrack devices are not properly set for passage ofequipment. (ASME B30.11-1993)

    Electric overheadtraveling crane

    BridgeCrane

    An electrically operated machine for lifting,lowering and transporting loads, consisting of amovable bridge carrying a fixed or movable

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