KSB GIW LCC 100-400, Руководство по обслуживанию

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LCC
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7.5.11 Impeller
Coat the shaft threads heavily with anti-seize compound.
Do
not coat the shaft sleeve faces which contact the
impeller and the step in the shaft.
Two 0.5mm (0.020 inch) aramid gaskets (400.10) are
placed between the shaft sleeve and the impeller hub face
to prevent galling and to ensure ease of impeller removal.
The gaskets should be installed dry, without grease.
Screw on the impeller tightly by hand. With larger sizes, it
may be convenient to hold the impeller stationary while
turning the shaft. Impeller lifting jigs are available to assist
in this operation (see Figure 7.4-2).
When assembly of the pump is complete, check the
impeller to suction wear plate clearance and adjust if
necessary, (see section on Axial Adjustment of Bearing
Housing).
7.5.12 Suction Plate and Liner ( LCC-H only)
Bolt the suction liner to the suction plate and install o-ring
before mounting to shell.
After mounting, the suction liner should protrude
approximately 1.0 mm (0.4 inch) from the suction plate at
the suction flange connection. This is normal and
provides the sealing surface for the suction piping.
7.5.13 Axial Adjustment of the Bearing Housing
In order to maximize the performance and reduce wear,
the clearance between the suction face of the impeller and
the suction liner must be adjusted to a minimum clearance
of 0.25 mm (0.010 in.). This is done by moving the
bearing housing assembly with the adjusting screw.
Before adjustment may proceed, the pump wet end must
be completely assembled. The stuffing box may be
packed before or after the adjustment procedure;
however, the axial set of any mechanical seal must be left
until
after adjustment is complete.
After insuring that the four bearing housing clamps are
slightly loosened, run the bearing assembly towards the
impeller end by means of the adjusting screw until the
impeller first begins to rub the suction liner. It is helpful to
slowly rotate the impeller during this procedure.
Next, reverse the adjusting screw until the clearance
between the impeller and the suction liner is brought to the
recommended value shown in the table below.
Impeller Nose Clearance
Shaft Size
Bearing Assembly
inch (mm)
All Sizes 0.010 (0.25)
Once the clearance is correct, lightly tighten the bolts of
the four bearing housing clamps by hand, making sure
that proper contact is maintained at all four locations.
Next fully tighten the bolts according to the requirements
of Section 7.5.15. Finally, firmly lock the adjusting screw
and nut together against the bearing housing tab.
Proper tightening of the bearing housing
clamps and adjusting nut is essential to
prevent movement of the rotating assembly during
operation. Failure to do so can result in severe vibration
and damage to all pump components.
7.5.14 Expeller Running Clearance
Proper adjustment of the impeller nose clearance as
covered in the section Axial Adjustment of the Bearing
Housing should result in proper expeller clearances in the
new condition and no further adjustments should be
necessary.
In some cases, however, adjusting the impeller after
excessive suction liner wear may result in the expeller
rubbing against the expeller plate. In other cases, it is
desired to optimize expeller performance rather than
optimize the impeller clearance.
The following procedure is recommended for optimizing
expeller performance or for setting the clearances in
pumps containing any worn parts:
1 With the suction plate/liner removed, adjust the
bearing assembly toward the pump end until the back
surface of the expeller just begins to rub the expeller plate.
2 Mount a dial gauge to indicate cartridge bearing
assembly axial movement and zero the dial gauge at this
location.
3 Now adjust the bearing assembly toward the drive (or
motor) end until the expeller vanes just begin to rub on the
expeller casing, or the impeller begins to rub on the hub
side of the pump shell, whichever comes first.
4 Adjust the bearing assembly toward the pump end
again approximately 1.0 mm (0.04 in.) to provide a
minimal expeller running clearance. If optimization of
expeller performance is desired, lock the adjustment at
this location
Optimizing the expeller clearances is
recommended only in cases where
expeller performance is marginal and a small increment in
performance is required to seal against the pump
pressure. Setting of clearances for optimal expeller
performance may result in excessive impeller clearance
and accelerated wear. If necessary, this may be remedied
by providing a custom fitted machined spacer with gaskets
between the impeller and expeller.
5 Reassemble the suction plate and check the impeller
to liner clearance. If not optimizing expeller clearances
set the impeller clearance as detailed in the section “Axial
Adjustment of the Bearing Housing”. Do not allow the dial
gauge to come closer than 1.0 mm (0.04 in.) to the original
zero setting or expeller rubbing may occur. If necessary,
consider the use of a spacer as mentioned in step 4.
Caution
Caution