Alfa Laval N Series User Manual

Operating Manual
Pumps fitted with externally mounted
mechanical seals :-
1. Ease the rotorcase off the dowel pins.
2. Take care not to damage the mechanical
seals on removing the rotorcase.
3. Keep in complete sets and label top or
bottom.
The pump head components may be
reassembled by reversing the above
procedures.
COMPONENTCOMPONENT
COMPONENTCOMPONENT
COMPONENT
NmNm
NmNm
Nm
lbftlbft
lbftlbft
lbft
Rotorcase Front Cover Nut 8.0 6.0
Rotor Retention Disc Screw 5.0 3.7
Removing the RotorsRemoving the Rotors
Removing the RotorsRemoving the Rotors
Removing the Rotors
1. Carefully loosen the front cover retaining
nuts, as there may still be residual pressure
in the system.
2. Remove the front cover nuts followed by
the cover.
3. Slacken and remove the rotor retention
discs.
4. To assist extraction of the rotors insert a
radiused end tool into the front recess of
the rotor.
5. Flush out the rotorcase before continuing.
Removing the RotorcaseRemoving the Rotorcase
Removing the RotorcaseRemoving the Rotorcase
Removing the Rotorcase
Pumps fitted with packed gland :-
1. Remove the gland follower nuts and
withdraw the gland follower.
2. Ease the rotorcase off the dowel pins.
3. Tap the rotorcase with a soft mallet on
both sides of the rotorcase. The rotorcase
must be supported during this operation
and not allowed to drop onto the shafts.
Rotor
Rotor
Retention
Disc
7.2 Dismantling the Pump7.2 Dismantling the Pump
7.2 Dismantling the Pump7.2 Dismantling the Pump
7.2 Dismantling the Pump
17

Alfa Laval N Series Specifications

General

Brand	Alfa Laval
Model	N Series
Category	Water Pump
Language	English