Fig. 5 Wall Crane
crane, standby: Used occasionally or intermittently when required, this crane is not regularly in service
crane service, normal: when operating at less than 85 percent of rated load and not more than ten lift cycles per hour (barring isolated instances) is involved in the crane service
designated person: selected or assigned by the employer (or a representative of the employer), this person is considered competent to do particular jobs
equalizer: When a rope’s length or stretch is unequal, this device compensates.
hoist motion: type of motion used to lower or lift loads.
drift point: while the motor is not powered, this point on a manual controller or a travel motion master switch keeps the brake released. Coasting will then be possible.
class I locations: flammable vapors or gases may be present in the air in large enough quantities to produce ignitable or explosive mixtures at these locations
class II locations: combustible dust is present, making these areas hazardous.
class III locations: easily ignitable fibers or flyings are present, making these areas hazardous, though these fibers or flyings are probably not going to be in suspension in the air at high enough levels to produce ignitable mixtures
limit device: this device is operational by some motion or part of a power-driven hoist, bridge, or trolley to limit movement
crane, wall: a crane that has a cantilever frame that may have a trolley and is kept up by columns of a building or a side wall. This type of crane operates on a runway connected to the columns or sidewall and is meant for travel.
hook, latch-equipped: this hook has a mechanical tool used to close the throat opening of the hook
crane service, severe: when abnormal operating conditions are involved in either heavy or normal crane service
drum: the ropes are wound, for lowering or lifting a load, around this cylindrical member.
end tie: Connecting the ends of the bridge girders, this structural member keeps the square shape of the bridge.
exposed: when one would have the ability to contact, carelessly, a hazardous object due to its lack of isolation or guard.
gantry leg: this structural member raises an end tie or bridge girder from the sill.
hazardous (classified) locations: A fire or explosion hazard may exist in these areas. Depending on the properties of the flammable liquids, gases, or vapors, or combustible fibers or dust that may be present and the probability that a combustible or flammable concentration or quantity is present these areas are then put into different classes (see National Electrical Code, ANSI/NFPA 70)
lifting devices: magnets, hook-on buckets, grabs, and other supplemental devices required for ease of handling some loads, these are not reeved onto the hoist ropes. One must consider the weight of such devices in the rated load.
crane service, heavy: when operating in excess of 10 lift cycles per hour or at 85 to 100 percent of rated load as a regular specified procedure is involved in the crane service
hoist: these units of machinery are used for lowering or lifting loads.
load: superimposed weight on the hook or load block at its total.