Harrington NTH, Operating Instructions Manual

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Trouble Shooting
A. Broken Chain
1. Trouble: Load chain is broken near its end.
Cross link bent.
Tail pin bent or deformed.
Cause
Load chain lowered excessively.
Explanation of Cause.
Lowering without noticing that there is no
chain remaining.
When chain is fully lowered, the force on
hand chain suddenlybecomes
heavier when
the end of chain runs against the guide roller.
Additional lowering results in a bent or broken
link.
-- - -,
Remed~ Pay attentionto load chain during operation.
Upon feeling a sudden resistance, stop operation.
During lowering operation, from time to time check to see ifthere is idle
chain remaining.
2. Trouble: Longer portion of broken chain has been rolled on load sheave.
Load sheave is unusually deformed.
Unusual flaw or twist remains in links adjacent to broken link.
Guide roller is unusuatly deformed.
Cause
Load chain twisted.
Explanation of Cause
When load chain -is lifted with a twist, the twist
becomes tighter as ,chain is Jiftedand it is rolled
onto load sheave. Further liftingwill
finallycause chain to break.
Remed~ Jerk hand ~ain by 2-or 3 people to loosen screw. In the event that the
screw is fUsted, disassemble and replace defective parts including screw.
,- -
3. Trouble:"The instant lowering operation is started, the load comes down.
Cause
Large amount of foreign matter
in the brake assembly.
Improper assembly of
brake.
Explanation of Cause
Improper assembly of brake system.
<"
Friction plates should be inserted on both sides
of ratchet disc, however, plates were inserted on
only one side, or one plate was left out.
It occurs when the friction plate stuck to the ratchet
disc.
Brake surfaces are
oiled excessively.
Remedy: Disassemble and replace defective Friction Plate
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