Pin Breakage
CAUSES: Crack starts on outer surface
and spreads through entire pin at a fast rate
(not nearly as common as with Sealed
Track Pins).
ACCELERATORS: Impact loads com-
bined with other loads caused by tight
track, severe packing, too wide shoes and
effects of worn rear rollers.
EFFECT: Track separation with little or
no warning.
REMEDIES: Eliminate or reduce control-
lable accelerator variables, particularly
too-wide shoes and entry of non-extrud-
able packing materials (rocks, etc.) into
the sprocket bushing contact area.
The following problem is externally visible
and while the cause is the same as with
Sealed Track the effect is different and
should be noted.
Pin End Wear
CAUSES: Sliding contact with track guid-
ing and/or roller guards and/or rocks.
(May be seen on either or both ends).
ACCELERATORS: Uneven terrain, and
side-hill operation, too wide shoes, worn
rolling component flange and misalign-
ment are many controllable variables.
EFFECT: Reservoir hole may have to be
de-burred and re-chamfered to remove the
stopper and plug at maintenance time. Pin
end may have to be re-chamfered before
pressing into link to prevent bore broach-
ing and subsequent lubricant loss after
track press work.
REMEDIES: Eliminate or reduce control-
lable accelerators.
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General Information
SEALED & LUBRICATED TRACK PINS & BUSHINGS