Experimental measurement of rolling bearing torque loss in a modified Four‐Ball machine: An improved setup.

This work presents an improved method for the measurement of the rolling bearing torque loss using a modified Four‐Ball machine. The new assembly allowed precise and accurate rolling bearing torque loss, while operating at constant temperature, controlled by means of liquid cooling‐heating system in which a thermal fluid is carried through the centre of the driving shaft. Several rolling bearing test campaigns are performed, using a fully formulated ISO VG 150 poly‐α‐olefin gear oil. The frictional torque loss is measured and compared with models available and the surface roughness of the rolling bearing races is observed using an optical profilometer. [ABSTRACT FROM AUTHOR]