CASE CONSTRUCTION 1150M - Page 140

6-WORKINGOPERATIONS
Recommendedapplication
ExtendedLifeTrackisrecommendedinhighabrasive/lowimpactapplicationswherebushingwearissevere.The
narrowestpossibletrackshoethatwillgiveadequateotationshouldbeusedtoobtainmaximumlifefromthesealed
andlubricatedstandardpinandbushingjoint.FieldtestinginabrasiveconditionshasproventheExtendedLifeTrack
bushingwillobtainuptotwicethewearlifeastheconventionallubricatedtrackbushings.
NOTE:Ifthemachinehasbeenparkedforanextendedperiodoftimeorisworkingincorrosiveenvironmentalappli-
cations,checkthebushingsbeforeoperatingthemachine.Loosenthebushingsiftheywillnotrotate.
Thismaybenecessaryonnewchainswheretheclearancebetweenbushingsisminimal.
Uncontrolledwearfactors
Normalundercarriagewearisanormalpartofmachineoperation.Soilandunderfootconditionscannotbecontrolled.
Theseincludeabrasivesoils,impact,packingandmoisture.
Abrasivesoils
Groundsurfaceshavedifferentlevelsofabrasiveness.Thehighertheabrasiveness,thehighertheundercarriage
wearrate.
Moistureplaysamajorroleintheabrasivenessofsoils.Asandslurrywillbelessabrasivethanadampsand.Wet
abrasivescreategrindingcompoundlikeconditions.
Lowabrasiveness
Siltsandclaysarelowabrasivesoils.Whenwet,thistypesoilfeelsslickandcanbeeasilymolded.
Moderateabrasiveness
Siltsorclaysthatcontainalowamountofroundedsandparticlesandenoughmoisturetosticktogetheraremoder-
atelyabrasive.
Highabrasiveness
Highabrasivesoilscontainahighamountofsharp,irregularshapedsandparticles.
Impact
Impactisbestdescribedastheamountofgrouserpenetrationintheground.Theeffectofhighimpactloadscanbe
reducedbyreducingthemachinespeedandbyusingthesmallesttrackshoespossible.
LowImpact
Trackshoegrouserswillcompletelypenetratethegroundsurfacewithlittleornorockorotherirregularities.
HighImpact
Trackshoegrouserswillnotpenetratethegroundsurface.Largerockorlargeirregularitiescausehighimpacton
theundercarriagesystem.Rockyterraincausesbending,breaking,andchippingofthecomponents.Reducethe
machinespeed,andusethesmallesttrackshoespossible.
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