Tension Nut Assembly and Adjustment of the vertical turbine pump

Enclosed lineshaft units of the vertical turbine pump use a tension nut which is at the top of the enclosing tube and must be tightened for proper operation. Refer to Figure 8-3 for general construction.

1. Clean all O-ring sealing surfaces including the groove in the tension plate and oil lightly.

2. After assembling the discharge head to the column, install the tension plate (ensure that both O-rings are in place), and allow the O-ring to slide down outside of tube adjusting nipple. Lightly oil the outside of the tube adjusting nipple prior to installation of tension plate.

3. Bolt the tension plate into place.

4. Slide the tension nut over the shaft and thread into inside of the tube adjusting nipple (left hand threads) until the tension nut is snug against the tension plate. Continue to tighten the tension nut until the lockscrew slot lines up with the “first” tapped hole in tension plate (1/4 turn maximum).

CAUTION：DO NOT OVER TIGHTEN THE TENSION NUT

It is necessary that the enclosing tube have tension on it which is accomplished by

tightening the tension nut. However, excess tightening can distort or break the tension nut.

Do not tighten more than 1/4 turn on close coupled vertical turbine pumps.

5. Install the lockscrew and tighten.

6. Proceed to complete the installation.