Mixed friction test bench

Typical areas of application for the bearings tested here include aircraft engines and wind turbines. The plain bearings used there are investigated on the test bench with regard to their running-in and wear behavior in a state of mixed friction.

Before and after the test, the surface roughness of the bearing is measured using white light interferometry. The contour measurement on a form measuring machine, which is also carried out before and after the test, is used to gravimetrically determine the wear. The contact stress measurement on the test bench can be used to track online when the bearing is in or leaves the mixed friction zone.

Both pure running-in tests and endurance tests are carried out on the test bench. A running-in test is considered complete as soon as the contact stress has dropped and the roughness peaks on the bearing surface have been removed. The endurance test goes beyond this point and documents the wear behavior of a bearing in continuous operation that deviates from the running-in test. In addition, Stribeck curves can be recorded at different surface pressures.

The results of the measurements are used to continuously improve and verify the bearing calculation programs developed at the institute and adapt them to special bearings.

Key test rig data:

Parameters	Nominal value	Unit
Maximum speed	4000	min-1
Maximum radial plain bearing diameter D	100	mm
Maximum bearing width B	50	mm
Maximum bearing load	100	kN
Dynamic load superimposition	possible