Micropitting and pitting are typical fatigue failures, which occur on the flanks of highly stressed, case
carburized gears. Both failure modes are strongly influenced by the lubricating conditions and lubricant
properties. Standardized test methods with defined test conditions are available to evaluate the lubricant
performance regarding micropitting and pitting.
The FVA–FZG micropitting testis well established as the standard testmethod forevaluating the micropitting
load capacity of gear lubricants, but requires relatively high costs and is quite time consuming. Therefore an
efficient and consistent short test method was developed to classify candidate lubricants in terms of their
micropitting load capacity analogous to the FVA–FZG micropitting test and to supplement the existing test.
The results of the standardized short test method correlate well with the ones of the FVA–FZG micropitting
test.
Regarding pitting the standard FVA–FZG pitting test is a well known and widely used test method that has
proved itself to be suitable to discriminate the pitting load capacity of gear lubricants. In order to improve the
practice relevance of the test gears and test results, to reduce the influence of undesired phenomena and to
increase the reliability of the results an advanced pitting test procedure was developed. This new test
procedure is based on the existing pitting test but uses superfinished test gears with adequate flank
modifications. The more suitable test gears will improve the reproducibility of the test results and ensure a
closercorrelation oftheresultstopractical gearapplications. Thetestalsooffersthepossibilitytobeextended
by additional testing at a 2nd load stage and is seen as an improvement of the existing pitting test method.
The paper describes the new developed test procedures and shows basic examples of test results.
Furthermore it discusses the correlation and classification to the existing test methods.

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