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Bearings for Mechanical Drive Turbines 63
Figure 3.14 Evacuated housing
spray bar tilting-pad bearing
design. (RMT, Wellsville, N.Y.)
mixing and blocks some of the hot oil carryover. In 1991, Tanaka pub-
lished results showing the cooling effect of removing the end seals of a
bearing design similar to the one shown in Fig. 3.11. These results led
to the design depicted in Fig. 3.14 featuring spray bars, open-end seals,
and open housing drains.
Figure 3.15 shows the effectiveness of this evacuated housing design
compared to the pressurized housing design illustrated in Fig. 3.11.
This test was performed on a steam turbine with a 4.0-in four-pad
tilting-pad bearing loaded between pivots. The evacuated housing
design, which employs offset pivoted pads to further reduce pad oper-
Figure 3.15 Evacuated vs.
pressurized housing metal
temperature comparison.
(RMT, Wellsville, N.Y.)
