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When the liquid level on the suction side is
above the pump
(inflow under positive suction
head, fig. 1B), fill the pump by opening the suction
gate valve slowly and completely, keeping the
delivery gate valve and the air vent (ref. 6, fig. 1)
open to release the air. Close the plug when the
water reaches the air vent hole.
With a three-phase power supply make sure
the direction of rotation is correct.
For this purpose, with the gate valve at any aperture
position, check the pressure (with the pressure
gauge), or flow rate (sight check) after starting.
Switch off power, invert the connections of two
phases on the control panel, re-start and check the
pressure or flow rate capacity again.
The correct direction of rotation will provide a con-
siderably greater and easily distinguishable pres-
sure and delivery capacity.
Check that the pump works within its field of perfor-
mance and that the absorbed current shown on the
name-plate is not exceeded. Otherwise adjust the
delivery gate valve or the setting of any pressure
switches.
If a priming loss occurs (interruption of delivery flow)
or if a pressure oscillation is indicated by the
pressure gauge, make sure all the suction pipe
couplings are perfectly sealed.
Never run the pump for more than
five minutes with a closed gate valve.
Prolonged operation without a change
of water in the pump causes dangerous
increases of temperature and pressure.
6. Maintenance
Under normal operating conditions the pump will
not require maintenance.
ATTENTION: if the pump is temporarily used
with dirty liquids or water containing chlori-
de,
flush the pump briefly with clean water im-
mediately after use to remove any deposit.
If the pump has not been used for a long time and
does not start or gives no water (but electrical
connections are in order), the pump must be
removed and checked to see if it is choked by any
foreign matter or blocked by sediment, deposits or
any other cause.
When the pump remains inactive it must be
emptied completely if there is a risk of
freezing.
Disconnect electrical power before
any servicing operation and make
sure the pump cannot be accidentally
switched on.
7. Dismantling
7.1. Checking rotation of the shaft
Close the suction and delivery gate valves and
drain the pump casing before dismantling the
pump.
For dismantling and re-assembly see construction
in the cross section drawing.
While the pump is positioned horizontally, remove
the screws (14.24), the square nuts (14.28) the
base (61.00), the suction casing (16.00) with the
elbow (16.30). Hold the first stage casing (25.01)
tightly with one hand so that is does not rotate and,
with a wrench on the nut (28.04), turn the shaft in
the anti-clockwise direction.
If the shaft is blocked and cannot be freed, disman-
tling should continue until the cause has been found
and removed.
7.2. Inspection of the hydraulic parts
The O-ring (14.20) and then the complete motor
assembly with all internal pump parts are remo-
ved from the external jacket (14.02).
The first impeller can be inspected by removing
the first stage casing (25.01).
Once the nuts (28.04) and washer (28.08) are
removed the spacer sleeves (64.15), impellers
(28.00) and the other stage casings (25.02 and
25.05) can be dismantled one after the other.
Others parts should not be dismantled.
The motor and pump functions can be impaired
by erroneous procedure or tampering with in-
ternal parts.
7.3. Oil chamber
If the oil chamber has to be inspected, follow
these instructions:
CAUTION: there may be slight pressu-
re in the oil chamber.
Care must be taken to avoid a sudden spur-
ting of oil. Wait until the oil chamber cover
(34.03) has cooled down.
Before removing the lower mechanical seal
(36.00), loosen the screws (70.18) and raise the
cover (34.03), applying force simultaneously on
two opposite points of the cover rim, to let off pres-
sure from the oil chamber. Carry out this operation
while holding the motor in the upturned vertical
position.
When refilling the chamber use only white oil suita-
ble for food machinery and pharmaceutic use
(quantity = 35 g).
First, mount the fixed parts of the seal (36.00) on
the oil chamber cover (34.00) and then the oil
chamber cover (34.03) on the motor cover (70.00)
with the O-ring (70.09).
8. Spare parts
When ordering spare parts, please quote their
designation, position number in the cross section
drawing and rated data from the pump name plate
(typ, date and serial number).
Changes reserved.
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