Wilo NPG Series Installation And Operating Instructions Manual page 9

English
4.3.1 Thermal expansion
The pump and motor will normally have
CAUTION!
to be aligned at ambient temperature
and should be corrected to allow for
thermal expansion at operating tempe-
rature. In pump installations involving
high liquid temperatures, the unit should
be run at the actual operating tempera-
ture, shut down and the alignment che-
cked immediately.
4.3.2 Alignment methods
Ensure pump and driver are isolated electrically
and the half couplings are disconnected. Ensure
that the pump pipework, suction and discharge,
is disconnected.
The alignment MUST be checked.
CAUTION!
Although the pump will have been aligned at the
factory it is most likely that this alignment will
have been disturbed during transportation or
handling. If necessary, align the motor to the
pump, not the pump to the motor.
Alignment
Parallelism and concentricity check:
Check the alignment at three or four
CAUTION!
points, before pipeworks assembly.
with a rule
Admissible margin for a motor with roller bearings:
= 0.15 mm parallel checking
= 0.1 mm angular checking
with a sliding rule
The alignment will be definitive only
CAUTION!
after pipework connection (see § 4.4.4.).
12
with a comparator
with a caliper gauge
If necessary, improve the machine alignment:
Complete unit mounted on common base plate:
The machines are first aligned accurately in our
workshops. Usually, any misalignment observed
on-site is due to a wrong adjustment under the
base plate (disturbed during transport or because
of forces exerted by the pipework). It is only
necessary to rectify the adjustment under base
plate. If it proves to be insufficient, modify the
motor and the pipeworks adjustment.
Never connect the electric motor before the
setting has been completely finished.
Wilo AG 09/2005