Goulds Pumps VRS - IOM - Manual (Page 27)

IMPELLER CLEARANCE SETTING
A change in pump performance may be noted over time by
a drop in head or flow or an increase in power required.
Performance can usually be restored by adjusting the
impeller clearance. Each application is different and hence
it is necessary to monitor the amount of wear over a certain
period of time in order to set up an adjustment schedule.
Other factors which may indicate that impeller adjustment
is required are:
•
High thrust bearing temperatures resulting from
uneven adjustment of impeller adjusting bolts
•
Noise and vibration resulting from the impeller
rubbing the suction liner
Adjust the impeller clearance with the pump in the vertical
position.
s
! WARNING
Lockout driver power to prevent accidental start-up.
1. Lockout power to driver.
2. Remove the coupling guard (direct drive) or belt guard
(belt drive).
3. “Break” the coupling (direct drive) or remove tension
from belts (belt drive).
NOTE: Lubricate the adjusting bolts and nuts for easy
turning.
4. Loosen the thrust housing adjusting bolt nuts (415A)
and locking capscrews (356B).
5. Turn thrust housing adjusting bolts (9956)
counterclockwise to lower the thrust housing (134A)
until the impeller (101) touches the suction liner
(600R).
6. Turn the thrust housing adjusting bolts (9956)
clockwise to raise the thrust housing (134A) 0.030 in
(0.76 mm), which is the recommended operating
clearance. This adjustment is best measured with a dial
indicator. Adjust each bolt slightly each time around so
that the thrust housing rises evenly and is not cocked
in the bearing frame (228). Make sure the rotating
assembly turns freely throughout the entire rotation.
7. Tighten the thrust housing adjusting bolt nuts (415A)
and locking capscrews (356B), carefully noting that
the dial indicator does not change during final
tightening.
8. Make sure the rotating assembly turns freely
throughout the entire rotation.
9. Align the coupling (direct drive) or sheaves (belt
drive) as outlined in the installation section.
10. Replace the coupling guard (direct drive) or belt guard
(belt drive).
PUMP WASHDOWN
The pump is designed to prevent liquid from entering the
bearing frame. Care should be taken, however, to avoid
spraying a high pressure stream directly at the bearing
frame seals.
TROUBLESHOOTING GUIDE
INSUFFICIENT CAPACITY
•
Pump not primed, check the sump liquid level
•
Speed too low
•
Total head higher than pump rating
•
Insufficient NPSH
•
Impeller passages partially blocked.
•
Wrong direction of rotation
•
Mechanical defects: impeller worn or damaged,
defective gasket causing leakage
INSUFFICIENT PRESSURE
•
Speed too low
•
Air in liquid
•
Wrong direction of rotation
•
Mechanical defects: impeller worn or damaged,
defective gasket causing leakage
VRS IOM - 5/08
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