Xylem IMVIT R01 Model VIT Vertical Industrial Turbine Pumps - Manual (Page 17)

17
FLATNESS OF THE SEAL HOUSING
For this measurement, remove the mechanical seal if
the dial indicator stylus cannot rotate 360° on the top
surface of the seal gland.
1. Install the dial indicator as
shown, with the base 1)
Remove the lower coupling
components and attach the
base of the dial indicator to
the motor shaft.
2. Place the stylus at the top
surface of the seal gland, or
at the top surface of the seal
housing.
3. Slowly rotate the motor
shaft 360°.
4. Check that the face of the seal housing is square
with the shaft to within 0.002 in (0.05 mm) TIR.
CONCENTRICITY OF THE SEAL HOUSING
This measurement requires that
you remove the mechanical seal.
1. Install the dial indicator as
shown.
2. Rotate the motor shaft
by hand and run the
indicator in the inside-
machined surface of the
seal housing in order to
determine the concentricity.
3. If the indicator reads higher
than 0.004 in (0.10 mm) TIR, loosen the four
motor hold-down bolts and relocate the motor on
the motor base register.
4. Obtain the desired position.
5. Tighten the hold-down bolts and repeat the
indicator reading.
CONCENTRICITY OF THE HEADSHAFT
1. Reinstall the mechanical
seal if it was removed for
the flatness or concentricity
measurement.
2. Install the coupling assembly
and adjust the impeller.
3. Attach the base of the dial
indicator on the discharge
head or motor support.
4. Place the stylus on the shaft
between the top of the seal
and the bottom of the pump coupling.
5. Slowly rotate the motor shaft 360°.
6. Check that the shaft runout is within 0.004 in (0.10
mm) TIR, or as required by specification.
7. Drill and dowel the pin in three places in order to
secure the motor to the motor base after you obtain
the required runouts.
CONCENTRICITY OF MOTOR SHAFT USING
JACKSCREWS
1. Install the dial indicator
as shown, with the base
attached to the motor
support.
2. Rotate the motor shaft by
hand while you read the
dial.
3. Make sure that the runout
does not exceed NEMA
standards, 0.002 in (0.05
mm) maximum TIR.
4. If the indicator reads higher than 0.002 in (0.05
mm) TIR, using the jackscrews relocate the motor
on the motor base (sometimes no register).
5. Obtain the desired position.
6. Tighten the hold-down bolts (not the jackscrews)
and repeat the indicator reading.
Note: Adding or removing shims between the
motor and the discharge head helps alignment in
the vertical direction. The jackscrews are provided
to adjust the motor in the horizontal direction for
alignment.
INSTALLING THE TENSION PLATE WITH CAST IRON
TENSION NUT
INSTALLING THE TUBE TENSION PLATE
1. (See Figure 10). Lubricate tube threads and
underside of tension plate flange with thread
compound. Thread the tension plate (625) onto
the enclosing tube nipple (629) manually until its
shoulder rests on the discharge head.
TENSIONING THE ENCLOSING TUBE
The enclosing tube sags from its own weight as it is
installed and must be pulled tight (tensioned) to make it
straight. This section describes two methods of tensioning
the tube. The direct pull method is more precise and is
preferred. The second method--the wrenching method--is
given as an alternate.
NOTE: The correct tension is equal to the weight of the
enclosing tube plus 10%.
Weights per unit length for each tube size are given in the
Table 1. Multiply by total length of the tube to determine
the total weight.
TABLE 1 – Weight-per-foot of Enclosing Tubing
TUBE SIZE (INCH) WEIGHT PER FOOT (LB.)
1¼ 2.99
1½ 3.63
2 5.02
2½ 7.66
3 10.25
3½ 12.50
4 14.98
5 20.78
6 28.57