KSB GIW LCC 100-400, Руководство по обслуживанию

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LCC
18
Caution
Caution
7.5 Reassembly
7.5.1 General Instructions
The pump should be reassembled in accordance with the
rules of sound engineering practice. Use the sectional
drawing and bill of material for guidance.
See section 7.4.2 for safety precautions regarding lifting
plates with swivel hoist rings.
Before assembly, thoroughly clean all
shaft, housing bore, and end cover
surfaces with a suitable solvent to remove old grease and
any water, dust or grit. Clean all dismantled components
and check them for signs of wear. Damaged or worn
components are to be replaced by
original equipment
spare parts. Make sure that the seal faces are clean and
the O-rings and gaskets are properly fitted.
It is recommended that new seal elements (O-rings/
gaskets) be used whenever the pump is reassembled.
Make sure that new gaskets have the same thickness as
the old ones. Avoid the use of mounting aids as much as
possible. Should a mounting aid be required, use a
commercially available contact adhesive. The adhesive
should only be applied at selected points (three to four
spots) and in thin layers. Do not use cyanoacryiate
adhesives (quick-setting adhesives). If in certain cases
mounting aids or anti-adhesives other than those
described are required, please contact the sealing material
manufacturer.
7.5.2 Mounting of Bearings
The grease retaining ring (63-7, for
grease lubrication) or spacer ring (45-4,
for oil lubrication) must be placed on the
shaft between the bearings, and in the proper orientation,
before both bearings are mounted. Once the bearings are
mounted, they cannot be removed without risk of damage.
The grease ring is essential in protecting the taper bearing
from loss of lubrication in the event of high loadings.
Failure to install the ring may result in significantly reduced
bearing life.
The bearings are press fitted to the shaft and should be
heated to 120
o
C (250
o
F) by a suitable bearing heater, oil
bath, or other even heating device prior to mounting.
Flame heating is not recommended. When mounting, it is
important that the bearings are seated fully against the
abutting shaft shoulder.
In mounting the taper roller bearing, it is important to heat
the outer race (or cup) along with the inner races (or
cones) to ensure proper seating against the inner spacer
required by this preset clearance type bearing.
Before the taper roller bearing has cooled on the shaft,
use the lock nut
without lock washer to fully seat the
bearing against the shaft shoulder. (The lock washer must
be left out during this step to prevent damage)
After the bearings have cooled, remove the locknut and
reinstall
with lock washer against the taper roller bearing,
tightening the nut according to the torque given in Section
7.5.15.
Over-tightening can damage the lock
washer and allow the locknut to back off
during operation.
Do not back off the locknut any amount
after tightening in an attempt to set the
bearing clearances. The LCC taper
bearing has an internal spacer, which automatically sets
the internal bearing clearances.
After tightening, bend down one tab of the lock washer
into one of the mating grooves on the locknut. If none of
the tabs are aligned with a groove, locate the nearest one,
and further tighten the locknut until the tab can be bent
down.
Failure to bend down one of the lock washer tabs may
allow the locknut to back-off and lead to premature
bearing failure.
See Section 7.2.2.2 for grease lubrication requirements
Figure 7.5-1 LCC Drive End Taper Roller Bearing
7.5.3 Inserting Shaft and Bearings into Housing
After insuring the bearing outer diameters and housing
bores are thoroughly clean, insert the shaft with bearings
and grease (or spacer) ring into the housing from the drive
end. It will be necessary to align the grease (or spacer)
ring as it enters the housing since it has about 6mm (0.25
in.) of clearance with the shaft.
The bearings should slide easily and fully
into the bearing housing without
excessive force that would indicate possible dust or grit
between the bearings and the housing, and result in a
thrust preloading on the impeller end spherical roller
bearing. Preloading of the bearing will cause it to carry
thrust loadings, which would normally be carried by the
taper roller bearing and can result in overheating and
premature failure of the spherical roller bearing.
Caution
Caution
Caution