Twin-disc type rolling contact fatigue test rig available in the laboratory for performing the pure rolling contact fatigue tests is modified for conducting the rolling-sliding contact fatigue tests.  In this test rig, the test roller can be run to the desired speed using a variable speed DC motor while the standard roller is run using an AC induction motor at a constant speed through belt drives and couplings. The speed of the test roller is set to the required level based on the desired slide/roll ratio. Both the speeds of test and standard roller are continuously monitored using the speed sensors so that the set slide/roll ratio is maintained constant throughout the test durations.    

Coefficient of friction between the rollers is calculated from the current and voltage consumption of the DC motor. The test roller unit is mounted on a linear motion slide and desired contact load is applied using the hydraulic cylinder connected to a hydraulic power pack. The contact load is maintained constant throughout the test duration and continuously monitored using a load cell mounted. Lubricant oil is continuously gravity fed to the contact zone. Temperature of oil coming out of the contact zone is measured using a copper-constantan thermocouple. Lubricant oil flow is kept constant throughout the experiment and the output oil temperature is not allowed to exceed 323 K.  The lubricant oil coming out the contact zone is directly collected using a clean oil sample collector kept below the contact zone for ferrographic analysis.