Centrifugal Pumps Design and Application 2nd ed - Val S. Lobanoff, Robert R. Ross (Butterworth-Heinemann, 1992)

Rolling Element Bearings and Lubrications 553
Figure 20-20. A small expansion chamber
accommodates vapor expansion and contraction
in hermetically sealed bearing housings
(courtesy of Gits Manufacturing Company,
Bedford Park, Illinois).
Figure 20-21. Bearing housing for so-called upgraded medium duty (UMD)
pump marketed in the U.S. since 1985 (courtesy of Carver Pump Company, Muscatine,
Iowa).
is immersed to the proper working depth, turns at the proper speed, and
is surrounded by lube oil of the proper viscosity. This is graphically illustrated
in Figure 20-23, which is derived from Heshmat and Pinkus [9]. In
this context, fully effective would mean that the oil ring should deliver a
sufficient amount of oil even as the shaft speed increases. This is
achieved by the ring provided with grooves on the inside diameter,
whereas the ring with the conventionally executed inside diameter appears
to deliver sufficient amount only at low shaft speeds.