Sprocket Wear Patterns
The new sprocket reuse gauge makes
interpretation of sprocket tooth profile
wear patterns much easier. Also, sprocket
wear patterns should now be used only to
help determine the cause and effect of cor-
responding bushing wear patterns since
the gauge will indicate sprocket reuse.
As noted in the previous discussion the
sprocket reuse gauge ignores sprocket
tooth tip condition as the tooth tip is not a
criteria for remaining functional strength
and wear life of the sprocket or how it will
adversely affect the bushing after reuse.
The sprocket gauge locates low on the
tooth side, as wear here determines (1) the
remaining strength in the tooth to support
further bushing wear in the driving portion
of the tooth and (2) the degree of expected
sliding the bushing will be expected to
incur thus affecting its expected wear rate.
The wear patterns shown here should not
be assumed to be a result of sprocket wear
characteristics alone, and therefore corre-
sponding bushing wear pattern should be
studied. See the section entitled “Sealed
and Lubricated Track Pins & Bushings.”
Also, since some sprocket wear patterns,
(particularly on the outside surfaces and
tips that face the links) are a result of
snaky track guiding and alignment
problems, the sections covering those situ-
ations should also be consulted.
These are the most common profile wear
patterns found with Sealed and Sealed and
Lubricated Track as identified in each case.
Root Wear
(0-30 degrees from vertical) is a normal
expected wear pattern of Sealed and
Lubricated Track in the absence of severe
packing and with Sealed Track prior to
pitch extension.
CAUSES: Sliding contact with vertical
position of bushing during forward to
reverse direction changes and due to pitch
mismatch of minor packing effect and/or
advanced component wear.
ACCELERATORS: See “Bushing Verti-
cal Position” wear.
EFFECT: None on sprocket itself. In
absence of other wear patterns, improves
sprocket reusability.
REMEDIES: Eliminate or reduce control-
lable variables shown under vertical
position bushing wear. Objective should
be to extend bushing life, not sprocket life
in this position.
Reverse and/or Forward
Drive Side Wear
(30-60 degrees from vertical) is a normal
expected wear pattern of Sealed and
Lubricated Track with moderate packing
and with Sealed Track with track pitch
extension with or without packing.
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General Information
SPROCKETS