Experimental Study of Stable High-Speed Oil Rings

Abstract

An experimental investigation was conducted on the behavior of oil rings for bearing sizes ranging from 75 mm (3 in.) to 305 mm (12 in.) in diameter. The characteristics of rings through several regimes of operation were determined up to journal speeds at which the ring becomes unstable and oil delivery ceases. Emphasis is placed on the fact that, of the oil lifted up by the ring, only a small portion is actually delivered to the bearing clearance so that in most cases the bearings run under starved conditions. A parametric study of ring weight, size, shape, tooth depth and orientation, as well as ring material yielded an optimum ring configuration from the standpoint of maximum oil delivery to the bearing. In addition, a stabilizer in the shape of an anchored spring leaf whose free end projects into the film between ring and journal surfaces was designed and shown to contribute substantially to raising the amount of oil delivered and to extending the range of stable ring operation.