GETTING T TH
REPLACEMENT
RIGHT
A
n excavator operating with worn teeth suffers
from increased fill times. Worn teeth lose their
wedge profile and thus require increased cutting
force to penetrate material. These effects reduce
overall productivity, increase energy consumption and induce
premature wear on other components.
Permitting excessive tooth wear has an additional
consequence: as the tooth wears, so does its retaining pin. If
the pin or the tooth wears beyond a critical point, the tooth
may fall off during digging. Amissing tooth not only further
reduces operational performance, but the subsequent wear on
the adapter is more difficult to repair, particularly in cases
where the adapter is welded to the dipper itself. Missing teeth
can also be accidently loaded with the excavated material and
delivered to the crushing plant where they can jam the
crusher. Extracting a tooth from the crusher is a dangerous
and expensive operation, and can bring production to a
standstill.
Routine shovel maintenance requires regular tooth
change‑outs. Depending on the mine’s policy, teeth can be
Hairong Zeng, Motion Metrics, Canada,
presents tooth
change-out planning with machine vision assistance.
December 2015
|
World Coal
|
27
