Xylem FLYGT Flygt 2071 Installation, Operation And Maintenance Manual page 34

Maintenance
4. Check that the spacing sleeves are seated in the diffuser ring.
5. Press the diffuser against the impeller.
6. Tighten the adjusting nuts so that they lie flush against the diffuser ring.
7. Back off all adjusting nuts another half turn (counterclockwise).
The impeller clearance should be minimal when the impeller is tightened. Use the
adjusting washers to adjust the clearance.
Pumps equipped with polyurethane covering are extremely resistant to wear. If the
impeller does not rotate completely freely, the friction will generate a lot of heat. This
can result in deformed wear parts, a stuck impeller, or damage to the pump. The
impeller clearance should be 0.2–0.3 mm (0.008–0.012 in.) when the impeller is
tightened.
8. Place the nuts and the spring washer on the studs, and tighten the nuts evenly all
around.
The clearance between the impeller and the diffuser ring must be as small as possible.
9. Check that the impeller can rotate easily.
10. Grease the outside of the diffusers lightly.
11. Install the protective sleeves, the strainer, and the screw. Tighten the strainer with the
washer and the locking nuts.
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WS0017669A
WS001770A
Flygt 2071 Installation, Operation, and Maintenance Manual