Case 2050M - Page 152

6-WORKINGOPERATIONS
Partiallycontrolledwearfactors
Speed
Unnecessaryspeedcancauseahigherwearrateonpins,bushingsandsprockets.Thefasterthespeed,thefaster
thewearrate.Highreversespeedacceleratesbushingandsprocketwear.Reversespeedsarefasterthanforward
speeds.Wearrateisafunctionofspeedanddistancetravelednotjusthoursworked.
Impact
Highspeedwillincreaseimpactloadingwhenthereislowgrouserpenetrationonhardsurfacesorwhenworkingin
rock.
Impactcancausestructuralproblemssuchasbending,crackingorbreakageofcomponents.Thiscanalsoaffectpin
andbushingretentionandbushingcracking.Fracturescanbecausedbyawornchain.
Turning
Wearrateincreaseswithincreasedturning.Turningincreasesinterferenceloadsbetweenmovingcomponents.
Turninginreverseacceleratesbushingandsprocketwearduetoincreasedloadstransferredfromtherotationofthe
bushingsagainstthesprocketinreverse.
Trackslip
Wearrateonallcomponentsincreaseswhentracksslip.Trackshoegrousersareaffectedduetoincreasedsliding
betweenthegrouserandtheground.
Favoredsideoperation
Wearrateswillincreaseonallcomponentswhenonlyonesideofthemachineisfavored.Wearincreasesasmore
powerisappliedtothefavoredside.Morepackingandslippagewilloccuronthefavoredsidethatwillresultinan
increasedwearrate.
ReverseOperation
Avoidexcessiveuseofreverseoperation.Thisisnonproductiveuseofthemachinethatacceleratesbushingand
sprocketwear.Mostspeedsarefasterinreversethanforward.
Dozing
Dozingshiftsthemachineweighttothefrontcausingafasterwearrateonthefrontrollersandidlers.
Ripping
Rippingwillshiftthemachineweighttowardtherearcausingafasterwearrateontherearrollers.Duringsevere
applications,thesprocketsandtrackbushingswearmuchfaster.
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