Maintenance

Sleeve Bearing

1120 Frame (See Figure 7)

1.Check replacement bearings for nicks or shipping damage. Do not scrape.

2.Carefully remove the bearing housing cap by first lifting straight up, then pulling away from the bearing area.

3.Remove top half of bearing liner.

4.Remove the bolts at the split line of the oil ring, disengage the dowels, and remove the oil ring.

5.Remove bearing temperature probes if so equipped.

6.Raise the shaft slightly and support it.

7.Rotate the lower bearing half 180° and remove the lower half of the bearing liner.

8.Reassemble, reversing the steps above. Apply sealant. (See MAINTENANCE, SEALING PARTS for proper sealing of this bearing design).Be careful not to disturb or jam the seals when replacing the upper half of the bearing capsule.

9.Lubricate. Turn motor by hand to be sure of proper fit and oil ring operation.

10.Start motor without load and check oil ring operation.

End Float – Sleeve Bearings

Control of rotor end float in sleeve bearing motors is maintained in the drive end bearing. The total end float is 0.5 inch. On the 500, 580, 680 and 800 frames, the bearings are located axially by shims between the bearing bushing and the bearing capsule shoulders . On the 1120 frame, the shims are located between the bearing housing mounting flange and the bearing bracket. The shims permit the bearing to be adjusted axially to maintain coincidence of electrical and mechanical center. Any adjustment of the axial position of one bearing should be accompanied by the same axial adjustment of the opposite end bearing.

The coupling should limit the end float of the shaft to ±0.18 inch from the mechanical center. The limited end float coupling prevents the rotor from rubbing against the bearing shoulders during operation.

Figure 7. Sleeve Bearing Construction

1120 Frame.

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