| There are two basic varieties of
powered hoists used for high rise access. They lift and lower a powered
work platform, the drum hoist or traction hoist. All hoists used in the
industry are “man rated”, requiring a primary and secondary
brake and an “over speed” protection device. The drum hoist,
powered by electricity, collects wire on a traditional flanged drum located
under or just behind the stage work area. The support wire rope has its
end clamped off to the flange for protection against the rope accidentally
spooling off the drum.
The custom designed and fabricated stage is therefore
often made to be modular, utilizing stage sections that couple together
in various lengths as needed for any of the building’s roof top
areas. To accomplish this, the stage is constructed in modular lengths
from as short as two feet to as long as twenty feet. The stage’s
end sections contain the power units and the center sections pin together
to create various lengths, like adding leaves to a dining room table.
Both the truss type and the ladder board variety of stages can incorporate
the modular design.
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