9.- CONSTRUCTION
Fig. 5 shows standard ENR pump. It may exist
variations depending on the size.
10.- DISASSEMBLING
Before disassembling the pump, make sure the
pump is stopped and the motor is disconnected
from the power supply.
(1) Remove the motor from the common base.
Check the elastic part of coupling.
(2) Remove the bolts of the casing and pump
foot. Separate the casing form the rest of the
pump; now you can access inside the pump.
Check the erosion of the wear parts or other
abnormalities. Wear ring must be changed when
clearance between impeller and ring was appro-
ximately 1mm.
(3) Take the impeller out by removing the washer
and the impeller nut. If the impeller is stuck, due
to rust, tap gently on the end of the shaft with a
plastic hammer.
(4) Remove shaft key. Take the rotating part of
mechanical seal out. Remove bearing support
bolts. Take the casing cover out taking care not to
damage sealing faces of mechanical seal.
26
Stationary part of mechanical seal can be taken
out by pulling it from behind with an appropriate
tool.
In packing execution, remove the packing gland
nuts and take out the gland, packing rings and
lantern ring.
Take the deflector ring out.
(5) Remove bearing housing covers. Take the
shaft out by carefully hammering on shaft end
until the first bearing get out of its housing. Place
the second bearing on position and follow ham-
mering until the shaft get totally out.
Review the condition of bearings checking that
they turn softly and without strange noises. There
must not be any grease leakage (in such execu-
tion).
(6) The pump should be re-assembled using the
reverse process to the disassembling, paying
attention to the following points:
- Clean the sealing faces of mechanical seal with
a dry soft cloth. Mount the stationary part of the
seal with a vegetal oil bath.
- Change pump gaskets.
- Change all worn or damaged parts.
- Gradually tighten bolts in a symmetrical manner.
- Mount the motor and center it to the pump follo-
wing the procedure described on section "6.3
Centering"
(ENGLISH)