Lull 644E-42 Operation Manual - Manual (Page 158)

156 Model 644E Origin 3/04
General Maintenance
Elongation - Extend Chain Only
When the original length (1) of 12.00" (305 mm) per foot of new chain has
elongated from wear to a length (2) of 12.36" (313 mm), the chain must be
discarded and replaced.
It is important to measure the chain in the section that moves over the sheaves
because it receives the most frequent articulation. Measuring the chain near its
clevis terminals could give an inaccurate reading. The ends of the chains, near
the clevis terminal, will not have flexed as frequently, if at all, as nearer the
middle of the chains.
Measure across a span of 13 pins at the center of the extend chain. Measure
from pin center to pin center. Because the retract chain is inside the boom you
will not be able to measure the chain. Refer to the Service Manual for inspection
of the retract chain.
The maximum measurement allowed is 12.36" (313 mm). If the measurement is
more than 12.36" (313 mm), the chain must be replaced.
OU0900
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