Understanding SOS Service Tests - PEHP7076-02

More documents

Recommendations

Info

S·O·S Wear Rate AnalysisPrevent problems and reducecosts by knowing wear ratesWear Rate Analysis is an integral partof our S·O·S Services program that helpsyou maintain equipment performance andmaximize availability. Through regularlyscheduled testing of oil samples fromyour engine, hydraulics and powertrainsystems, Wear Rate Analysis detects tinymetal particles caused by componentwear. By monitoring trends in the typeand quantity of particles, you can getearly warning of problems before majordamage occurs.Understanding wear metalsEvery oil-washed system—engines,hydraulics, transmissions, and final drives—produces wear metals in everyday operation.If wear accelerates, the concentration ofwear metal particles increases, signaling aproblem. Wear Rate Analysis allows you tofind problems before they result in majorrepairs or machine failure.Wear Rate Analysis can detect particles thatrange up to about 10 microns in size. Wearmetal concentrations are expressed in partsper-million(or ppm). The S·O·S Servicesprogram tests for at least nine differentsubstances: copper, iron, chromium, lead,tin, aluminum, molybdenum, silicon andsodium. All are wear metals found inCaterpillar machines and engines exceptsilicon (which generally indicates dirt) andsodium (which indicates water or coolant).Certain elements in a sample may be fromthe oil additive package rather than fromwear within the system. Skilled dealerinterpreters can tell the difference betweennormal elements and those that indicateabnormal wear.Trending wear metalsin your equipmentTwo identical machines under identicalconditions may generate wear particlesat different rates. Our S·O·S interpretershave access to a large database of samplesfor comparison with samples from yourequipment. However, your own machinesprovide the best guidelines for appropriatelevels of wear metals in each compartment.That’s why trending is an essential partof Wear Rate Analysis. After three sampleshave been taken from a particular compartment,a trend for each wear metal isestablished. Our interpreters then comparesubsequent samples to this trend lineto quickly spot deviations as well asmonitor gradual changes in concentrationlevels. This attention to trends also assistswith life cycle analysis, helping youoptimize productivity.The technology behindWear Rate AnalysisWe use an emission spectrometerto perform Wear Rate Analysis.The spectrometer determines wearelements and silicon in a sampleby subjecting the oil to very hightemperatures. At these temperatures,the elements in the sample are“atomized,” with each emitting adifferent wavelength of light energy.An optical system measures andrecords the light energy and calculatesthe results in parts-per-million foreach element.
MAINTENANCE SERVICESEngines–Top EndPrimary ElementCombinations of Classic Wear ElementsSecondary Element Potential Wear Probable Problem Area/CausesSilicon (dirt) Iron, Chrome, Aluminum Liners, Rings, Pistons Air Induction System/Filter Dirt ContaminationIron Chrome, Aluminum Liners, Rings, PistonsAbnormal Operating Temps., Oil Degradation,Fuel and/or Coolant Contamination, Stuck/Broken RingsChrome Molybdenum, Aluminum Rings, Pistons Blowby, Oil Consumption, Oil DegradationEngines–Bottom EndHydraulicsIronLiners, Gears,Valve Train, CrankshaftAbnormal Operating Temps., Lack of Lubrication,Contamination, Storage (Rust)Silicon (Dirt) Lead, Aluminum Bearings Dirt ContaminationLead Aluminum BearingsLack of Lubrication, Coolant Contamination,Fuel ContaminationSilicon (Dirt) Molybdenum, Aluminum Cylinders, Rods Dirt ContaminationCopper Iron Hydraulic Pumps Oil Degradation, ContaminationTransmissionsFinal DrivesIronAluminum, ChromeRoller or needlebearingsAluminum Iron, Copper Torque ConverterBearing fatigue/failureBearing wear/failureallowing contactSilicon (Dirt) Iron, Aluminum Gears Dirt Contamination, Clay Soils ContaminationIron Sodium, Chrome Gears, Bearings Water Entry, Preload LossPinpointing the causes andeffects of component wearBy comparing infrared (Oil Condition) test results with wear metalbuildup, we can pinpoint probable causes of elevated wear metals.The chart above illustrates some of the most common wear metals,their source(s), and the potential problems they indicate in oillubricatedsystems.Spectrometry detects dirt contamination, as well as wear metals.Silicon is the most common element indicating dirt entry, althoughsome clay soils also produce increased aluminum readings.Monitoring your componentsWhen S·O·S oil analysis identifies an increase in the concentration ofone or more metals, it can point to the wearing component most likelycausing the increase and, often, the probable cause. For example, asudden increase in copper and iron in a hydraulic oil sample wouldprobably indicate a problem with the hydraulic pump caused by eitheroil degradation or contamination (see chart, above).Silicon/aluminum ratio indirt varies by locationThe primary constituents of dirt areminerals containing silicon and aluminum.The ratio of these two elements varieswidely from place to place. Clay soilscontain nearly as much aluminum assilicon. This is one reason why localinterpretation of your sample results isimportant. We are familiar with the soilsin your area, giving us the best understandingof the combinations ofelements in your samples.
Page 1: MAINTENANCE SERVICESUnderstanding S
Page 5 and 6: MAINTENANCE SERVICESIdentifying con
Page 8: Count on our experts.The S·O·S Se

Understanding SOS Service Tests - PEHP7076-02

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?