Doosan 50001, Руководство по ремонту

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SP001624 Swing Bearing
Page 6
SWING BEARING
MAINTENANCE
Operating Recommendation
The service life of the swing bearing may be extended if a
conscious, daily effort is made to equalize usage over both
ends of the excavator. If the excavator is used in the same
operating configuration day in and day out (for example, with
the travel motors always under the counterweight, or with the
attachment over one side of the machine more than the other),
the bearing's service life could be reduced. Taking a few
minutes in the middle of each work shift to reposition the
excavator, to work the opposite end of the bearing, will provide
a payoff with more even, gradual rate of wear and extended
service life.
Measuring Swing Bearing Axial Play
Periodic, regular checks of bearing displacement should be
made at least twice a year. Use a dial indicator. Push the
attachment against the ground to lift the excavator off the
ground and take measurements at 4 points, 90° apart, around
the circumference of the bearing (Figure 1).
Record and keep all measurements. Play in the bearing should
increase minimally from one inspection to the next. Eventually,
however, as the bearing begins to approach the limit of its
service life, clearance increases become much more
pronounced and the actual measured play in the bearing could
exceed twice the value that was measured when the machine
was new.
Measuring Bearing Lateral Play
When vertical checks are made, the side to side play in the
bearing can be checked by fully retracting the arm and bucket
cylinders and extending the tip of the bucket as far forward as it
will go. With the excavator parked on a flat, level surface and
the bucket tip just off the ground, push against the bucket
sideways to take up all the lateral clearance in the bearing.
(Less than 100 lb of force should be required to move the
bucket over all the way.) Check lateral play in both directions
and record the values. When the bearing is beginning to
approach the end of its service life, measured lateral clearance
should start to show larger and larger increases.
FG013224
1
2
Figure 1