Maintenance

To Replace Antifriction Bearings

1.Remove bolts holding end caps to housings.

2.Remove bolts holding bearing housings to yoke.

3.Remove bearing housings.

4.Remove the bearing with a puller. See Figure 5.

5.Check shaft and housing diameter for proper size with micrometer.

6.Heat the new bearing in an oven (200°F). While it is hot, slide the bearing onto shaft – make certain that the inner race makes a firm even contact with shaft shoulder. Do not subject bearing to impact.

7.Let bearing cool - pack bearing caps with the proper grease.

8.Reassemble end caps and housings.

The amount of grease to be used when repacking a bearing after cleaning or replacement is shown in the table below:

Type

Operating

Grease Quantity*

Bearing

(End Caps)

Bearing

(Shaft)

Outer

Inner

 

Deep Groove

Horizontal

2/3 Full

1/3 Full

Ball

 

 

 

Roller

Horizontal

1/3 Full

1/3 Full

 

 

 

 

*Pack all open bearings full between balls or roller but remove excess grease on outside of retainers.

Figure 3. Ball Bearing Construction

500, 580 and 708 Frames

Figure 4. Ball Bearing Construction

788 and 880 Frames

NOTE

1.For best results, seal should be positioned flush with outer-most bearing housing surface. (Some frame sizes have shaft seal on only one end of the motor)

2.U.L. listed motors have special requirements. Assembly must be by U.L. certified shop or inspected by U.L.

Consult factory for U.L. listed motors.

Protect the shaft end with a cap. If bearing is reusable, make certain the puller applies pressure against the bearing inner race only. If puller will not hook the bearing inner race, fabricate a split bushing and install it between the bearing and the puller hooks.

Figure 5. Removing Bearing with a Puller

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