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swivel (except multiple reeved) and to the hoist, or provided with a means to prevent the end of
the chain passing through the hoist. The ends of the load chain shall also permit ready
replacement of the chain.
3.3.2.1.2 Load chain (roller chain type). The load roller chain shall be a free-rolling roller
chain which is readily replaceable. Material for pins, bushings, rollers, and sidebars of roller chains
shall be carbon or alloy steel and shall be of a hardness and strength to withstand the applicable
tests specified in 4.7.1 through 4.7.9 and a safety factor of 5 for the rated load of the hoist, based
on the ultimate strength of the material.
3.3.2.2 Hand chain. The hand chain shall be endless link chain and shall have a drop which
is approximately 2 feet less than the specified lift of the hoist. The hand chain shall have a
minimum rated strength of at least three times the maximum chain pull required to lift the rated
load. Connecting links are permitted. The hand chain shall be of a hardness and strength to
withstand the applicable tests specified in 4.7.1 through 4.7.9. The hand chain wheel shall be
compatible with the chain material selected.
33.2.3 Finish. The link load chain, the link hand chain, and the hook safety device shall be
protected by electro-deposited zinc to resist corrosion. Zinc coating shall conform to type I, class
Fe/Zn 13 of ASTM B 633 or type I, class 25 of ASTM B 695. The plating process shall be such
that there will be no impairment in free movement of any chain link after plating. The roller
chain shall have a blue oxide finish supplemented by a coating of "combination lubricant and rust
preventative.
3.3.3 Load chain sprocket and shaft. The load chain sprocket for link chain hoists shall have
pockets accurately shaped to fit the link of the load chain. The load chain sprocket for roller
chain hoists shall accommodate the links of the roller chain. The load chain sprocket may be
integral with or rigidly connected to the load chain shaft. Welding of the load chain sprocket to
the shaft is not permitted.
3.3.3.1 Chain guides. Enclosed chain guides shall be provided to assure that the hoist load
chain enters the sprocket in the proper position to prevent misalignment or jamming of the hoist
load chain and sprocket. These guides, if bolted on, shall have locknuts or other means to prevent
loosening under vibration.
3.3.4 Hand chain wheels. Hand chain wheels shall have accurately shaped pockets to fit the
hand chain. The wheels shall be equipped with a chain guide that will permit operation of the
hand chain from an angle 10 degrees out from either side of the chain wheel without slipping or
jumping the wheel rim.
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