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distance from the trolley, and measuring the required pull by means of weights or a spring balance
attached to the cable or cord Failure to meet the requirements for maximum pull to traverse the
hoist shall constitute failure of this test (see tables III and IV for applicable hoist).
4.7.6 Geared trolley. The pull required on the geared trolley hand chain to move a capacity-
loaded hoist (gear trolley suspension) along a straight portion of track shall be determined by
attaching weights or a spring balance to the chain. Failure to conform to the requirements for
maximum pull to traverse the hoist shall constitute failure of this test (see tables III and V for
applicable hoist).
4.7.7 Drop. Sample hoists shall be drop-tested by dropping the hoist rated load from heights
programing from 1 through 4 inches, in l-inch increments, in such a manner that the falling load
will be stopped by the hoist load brake. The test load shall be supported by the hoist hook during
the drop test, Type H, convertible capacity hoists shall be reeved and loaded for maximum rated
load for the drop test. The load hook shall be lowered to extend 4 feet below the body of the
hoist. The test arrangement shall be such that the dynamic faces will pass through the hoist from
the load hook to the suspension hook. The hoist shall be suspended from a clevis or equally rigid
connection or by its own trolley from a beam of such strength that it will not permanently deform
as a result of the test. The structure shall be rigid to limit the deflection of the hoist supporting
beam, measured at the center of a 6-foot span to 0.020 inch when supporting 20 tons. Trolley
--
type hoists shall be secured against lateral motion. The hoist chain shall not slip downward more
than one link (or 1 inch maximum) for the entire test, measured from the original position of a
pre-selected chain link to the hoist body before and after the test.. The hoist shall not fail, so as
to drop its load, under the four successive impacts, although deformation of the hoist hooks and
chain is permissible. Separation of component parts from the hoist shall constitute failure of the
test. The hoist unit need not be operable at the conclusion of this test.
4.7.8 Life test. Hoists of all classes and types, except type H, shall be tested to 5000
continuous operating cycles when single reeved. The operating cycles for testing multiple reeved
hoists shall be determined by dividing 5000 by the number of hoist load lines. An operating cycle
shall consist of lifting and lowering the hoist rated load through a minimum distance of 4 feet, with
a 6-second maximum pause between lift and lowering This test shall be performed at a minimum
speed of 15 ft/min and a maximum of 70 ft/min. All hoists shall be clean and free of foreign
material and excess lubricant. During operation of these hoists, no wear particles greater than
0.031 inch in any direction shall be generated. Operation of the hoists may be accomplished by
means of power operated equipment. The use of auxiliary cooling equipment for the power
operated equipment is permissible.
4.7.8.1 Type H hoist. Type H hoists shall be tested to
2000 continuous operating cycles when
single reeved. The operating cycles for testing multiple
reeved hoists shall be determined by
dividing 2000 by the number of hoist load lines. Convertible
hoists shall be reeved for their fixed
of lifting and lowering the hoist rated
rated load. An operating cycle for these hoists shall consist
hoists shall be operated at a minimum
load through a distance of 6 inches. Type H, lever operated
m
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