Wear-out products analysis in consistent lubricants

The contemporary conditions require means for diagnostics, control and forecast of bearings operation, without disassembling the units,

For example Fe, Cu, Cr and Si  concentration in lubricant should be controlled.

Rejection criteria are:
Si> 0.2%
Fe> 1.0%
Cr> 0.015%
Cu> 0.15%

High concentration of metal inclusion indicates bearing intensive wear-out and danger for further operation. Silicon presence in the lubricant indicates bad impermeability of the journal box and necessity of lubricant renewal.

X-ray fluorescence method provides direct determination of Si, Fe. Cr and Cu content in lubricants without sample preparation. The test material is mixed, filled in the sample cup, covered with polyethylenetereftalate film and put in spectrometer. Analysis is carried out automatically according to the program.

The advantage of the method is its rapidness and simplicity combined with high precision. All elements can be determined from one specimen.