Wilo Norma V Series, Installation And Operating Instructions Manual

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9.3.2.1 AUXILIARY PIPING
Make sure that intermediate bearing lubrication devise is switched off
and that there is no pressure in the circuit.
- Disconnect the hydraulic circuit.
9.3.2.2 DISCHARGE PIPING
If hot or dangerous liquids are pumped, make sure that
maintenance operators are trained and risks are known.
Procedures to avoid risks must be respected with care.
- Check that discharge pipe is isolated and perfectly drained.
- Disconnect the pump discharge pipe from main piping.
9.3.2.3 DISMANTLING OF PUMP UNIT
- Lift the pump with care and slide it out of the tank or pit.
While pump is moved away, make sure that lubrication piping is
not damaged : might be destroyed or bent.
- Put the unit down on the floor horizontally with discharge pipe on
pump side.
Secure the area around the hole left open upon the pit.
Make sure that the strainer will not bump on the floor when the
pump is put down on the floor : can be destroyed.
- Add shims under the column so that the pump casing do not lean
on the floor.
9.3.2.4 MOTOR ASSEMBLY TYPE TM AND TH
EQUIPPED WITH INTERM EDIATE BEARING :
- Dismantle the lubrication circuit from the pump.
9.3.2.5 DISMANTLING OF T HE P UMP DISCHARGE
PIPE :
- Shim under discharge pipe flange.
- Remove fastening bolts [6581] and put the discharge piping [9200]
flange on the floor.
- Remove the flange gasket [4590A].
9.3.2.6 DISMANTLING OF PUMP CASING :
- Remove the casing fastening screws [6577E].
It might be difficult to remove the casing from the back cover
(tight assembly or corrosion). Use screwdrivers to lever-up the
casing and separate casing from cover.
Danger from squeeze points. Depending on casing size it may be
necessary to use slings to lift the casing prior to dismantling.
- Remove casing seal [4596].
- Remove the strainer [6531]
9.3.2.7 DISMANTLING OF THE IMPELLER :
THREADED IMPELLER :
- Fit a chain wrench or bolt a bar to the holes in the coupling half, or
fit a keyed shaft wrench directly to the shaft.
- Turn the shaft counter-clockwise as viewed from the drive end of
the shaft with the wrench..
- Give the shaft a quick turn clockwise to sharply strike the wrench
handle against the work bench surface or a wooden block. A few
sharp strikes by the handle onto the bench/wooden block will free
the impeller from the shaft.
Variant :
Alternatively, twist the impeller by firmly grabbing hold of the impeller
and twist it counter-clockwise to make the wrench bump on the work
bench.
- The impeller is equipped with an O’Ring [4610.1]. A new one will
be used during assembly.
KEYED IMPELLER :
- Remove the impeller nut(s) [2912]
- Remove the lock washer if necessary and washer [2905].
- Lever out with 2 screwdrivers between impeller and back cover.
Danger from squeeze points. Handle impeller with care.