Protective instrumentation for large grinding mill trunnion bearings

CIM Bulletin, Vol. 74, No. 835, 1981

R.L. GUERGUERIAN Senior Design and Development Engineer, EUGENE BERCEL Manager of Marketing, Mining Equipment, Metal and Mining Section, Dominion Engineering Works Limited, Montreal, Quebec

Grinding mill hydrostatic trunnion bearings require an external pumping source to provide and maintain the oil film between the bearing members. In order to guarantee a predetermined minimum film thickness, the lubrication system tends to be oversized. The oil film is "indirectly" controlled by flow, pressure and temperature monitors with fixed settings on the conservative side. This can lead to excessive maintenance and abbreviated life for the lubrication system components. A reliable method of monitoring actual film thickness would not only provide greater mill availability, but also minimize maintenance costs.This paper describes the instrumentation installed in Dominion hydrostatic bearings, and presents results of field tests where the output of that instrumentation was recorded under various operating conditions.
Keywords: Equipment, Maintenance, Instrumentation, Grinding mills, Bearings, Trunnion bearings, Hydrostatic bearings, Lubrication, Oil films.