Follow this link to a collection of case studies.
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The Spectrum from a main shaft bearing on a wind turbine, NM52 900 kW, shows a damage on the outer ring. The shock pulse level is still very low but the spectrum shows a developing damage. The shaft is rotating at 22 rpm. The wind turbine generated 752 kW (84% of full effect).
Pulp and paper
The Color Spectrum Overview from a twin wire press verifies that the signal origins from the inner race. The twin wire press runs at 10 to 15 rpm. The patterns consist of the center frequency with sidebands. After the replacement, marked with a yellow square, the bearing signals completely disappear.
The Time Signal from a steel bar mill gearbox shows a broken roller. The bearing is running at 64 rpm. The time between the markers corresponds to the rpm of the cage, i. e. how often the rolling element moves in and out of the loaded zoon of the bearing.
The Shock Pulse Trend for the slow running overhead conveyor gearbox shows a steady rise since the first readings taken. Initially the gearbox was in the green and in good condition, over the past few months the readings have risen into the red and there are signs of minor damage.