Dear Members of forum,
Multi stage pump, for Boiler feed water pumps, had problem with high temperature in IB bearing , one of the hypothesis was Lubrication issue due to lubrication oil ring.
high temperature en journal bearings may be caused by:
excessive radial force; shaft internal eccentricity vs. pump casing, misalignment , eccentric Bearing housing.
lubrication issue: Oil ring not circular ( ovality in ring), not good viscosity of oil, the oil ring not turn, low oil level, oil ring too heavy, angular misalighment of bearing (not good contact between shaft and bearing), we did blue match to check bad contact problem
in our case, the problem was that the shaft was 0.007 inch eccentricity with respect to stufing box (seal bore), the bearing box was up , making excesive force in bearing causing high temperature and making the journal bearing failure.
we did new dowels for bearing box with new centering and the problem was solve out.