Category Archives: Data Interpretation

Sources of Silver Silver is a wear metal used as an overlay on some bearings, such as journal bearing for gas turbines or wrist pin bearings on EMD locomotive engines. Silver from these parts will increase disproportionately with iron. Zinc additized oils will accelerate the corrosion of silver in these applications, therefore the use of…

Sources of Chromium Chromium is a wear metal found in the coating of parts like valves, rods, rings, and bearings. Typically, increasing levels of chromium, and possibly nickel, disproportional with iron, indicate coating wear, whereas proportional increases suggest steel alloy wear. One form of proportional chromium and iron increase may arise from non-wearing parts made…

Sources of Nickel Nickel is a wear metal found in some machines using plain bearings, as lead and tin are the most predominant metals used in Babbitt overlay, with lesser amounts of copper, antimony, and/or arsenic. Typically, increasing levels of nickel are from an intermediate layer and therefore considered actionable. Nickel can also increase as…

Sources of Tin Tin is another wear metal expected in any machine using plain bearings, as lead and tin are the most predominant metals used in Babbitt overlay, with lesser amounts of copper, antimony, and/or arsenic. Typically, increasing levels of tin from this layer are not considered actionable, not until metals like copper or nickel…

Sources of Aluminum While lead is commonly thought to be wear metal, that is not always the case. One example would be an oil sample from an aluminum block engine compared to a steel block engine. The block itself may be a source of wear metals when the sleeves for the pistons are machined directly…

Sources of Lead Lead is an expected wear metal in any machine using plain bearings, as lead and tin are the most predominant metals used in Babbitt overlay, with lesser amounts of copper, antimony, and/or arsenic. Typically, increasing levels of lead from this layer are not considered actionable, not until metals like copper or nickel…