Some Designs for Mountings Incorporating Two Rolling Bearings and a Grease Relief System

Abstract

The designs for grease relief systems of the valve type for a mounting containing a single bearing are already well known. In some machinery, however, the bearing requirements cannot be satisfactorily met by a single bearing. In these cases a pair of bearings in the one mounting is needed. The design of the mounting is further complicated if, in addition to pairing the bearings, a grease relief system is also required. The paper gives eight outline sketches covering various designs of two-bearing grease valve mountings. All have been rig tested and the efficiency of each design categorized. For the experimental work 3-in (76·2-mm) bore medium series ball and roller bearings were used. These were grouped into six pairs. Each pair was tested, either paired in contact or axially spaced apart. Shaft speeds ranged from 1070 to 3600 rev/min, DN = 82 000 to 275 000. In the relief systems, either one or two valve discs were variously positioned above, below, and between the bearings. The paper should be of value to design engineers.