Flowserve WDX - Manual (Page 25)

WDX USER INSTRUCTIONS ENGLISH 71576322 06-05
Page 25 of 46
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5.5.1 Suction pressure above atmospheric
pressure
Open the air vent connection to allow the trapped air
to escape. Let liquid run out until free from air
bubbles.
5.5.2 Suction lift w ith foot v alve fitted
Fill suction pipe and casing with liquid at a pressure
of 1 to 2 bar from an external source. Vent as
described in section 5.5.1.
Foot valves are not recommended when
the pumped liquid has suspended solid particles.
They may lodge between foot valve seat and shutter.
5.5.3 Suction lift w ithout foot v alve
Pump casing vents on the suction volute must be
connected to an external vacuum pump priming
sy stem. If in doubt, please consult Flowserve.
5.6 Starting the pump
a) Ensure flushing and/or cooling/
heating liquid supplies are turned ON before
starting the pump.
b) CLOSE the outlet valve. If the pump is equipped
with a non-return flow valve and is to be started
with an opened discharge valve, verify that it is
closed by an adequate back pressure.
c) OPEN all inlet valves.
d) Open all valves of the minimal flow line to ensure
a minimal flow for the period the pump is running
against the closed discharge valve.
e) Prime the pump.
f)
Check that all plugs are tight.
g) Check that the gland lightly tightens the packing.
h) Ensure all vent connections are closed
before starting.
i) Start motor and check outlet pressure.
j) If the pressure is satisfactory, slowly OPEN outlet
control valve.
k) Do not run the pump with the
outlet valve closed for a period longer than 20
seconds.
l) If NO pressure, or LOW pressure, STOP the
pump. Refer to section 7, Faults; causes and
remedies, for fault diagnosis.
5.7 Running the pump
5.7.1 Venting the pump
Vent the pump to enable all trapped air to
escape taking due care with hot or hazardous liquids.
Under normal operating conditions, after the pump
has been fully primed and vented, it should be
unnecessary to re-vent the pump.
5.7.2 Pumps fitted w ith packed gland
If the pump has a packed gland there must be some
leakage from the gland. Gland nuts should initially be
finger-tight only. Leakage should take place soon
after the stuffing box is pressurized.