Maintenance - Wilo SCP Série Notice De Montage Et De Mise En Service

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• Check the mechanical seal for leak. In the start
phase (and also after downtimes) slight leakage
can be expected. Visual leakage checks are howe-
ver required from time to time. Distinctly visible
leakage will require an exchange of the seal. Wilo
offers a repair set containing all parts required for
an exchange.
• Check that the bearing is not overheating. Bea-
rings will normally run at a temperature of 30 ˚C-
35 ˚C above ambient temperature. The ideal run-
ning temperature of bearings is 40 ˚C to 60 ˚C for
ball bearings and 40 ˚C to 55 ˚C for bush bearings.
The temperature should never exceed 82 ˚C for
ball bearings and 75 ˚C for bush bearings. If the
bearings are overheating its cause should be
investigated immediately.
• If the foregoing checks are satisfactory, open the
delivery valve slowly and bring the pump gradually
up-to its rated parameters indicated in the data
sheet/name plate and based on pressure gauge
and ammeter readings. Unless the pump is fitted
with a special leak-off device, it should not be run
for a long period against a closed delivery valve.
Check that the driving unit is not being overloaded
during valve opening. Overloading may occur if
the pump is discharging into an empty system. If
the pumping unit fails to generate at least its rated
delivery pressure it must be stopped immediately,
the cause ascertained,
• Check vibration of pump set and ensure that
vibration level is within limits specified. Check
that noise level is within stipulated limits.
• the pumps may be run for 8 hours trial operation
and all the parameters like delivery pressure, cur-
rent, bearing temperature, etc. Be recorded perio-
dically.
Make the following checks at regular intervals. It is
recommended that they be made at every change
of shift.
• Check the suction and discharge pressure gauge
for normal operating pressure, if there is signifi-
cant drop in the suction or discharge pressure the
pump may have lost its supply. In the event of this
fault occurring, the pump must be stopped imme-
diately and the cause of liquid loss eliminated.
• Check the mechanical seal or stuffing box assem-
bly for overheating.
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8.3.4 Sealing system
Gland packing
CAUTION! Risk of damaging the pump!
If the gland plate is too tight, the packing stuff
will be immediately damage.
At the beginning of the operation, the leak at the
gland packing should be important. It should
reduce progressively after several hours by a
balanced and reasonable tightening the gland
plate. The gland packing must operate without
excessive temperature. The correct setting of the
gland packing let a permanent leak around 1 or 2
drops per seconds.
If this leak is too much and cannot be adjusted
with the gland plate, the packing stuff are worn
and must be replaced.
Mechanical seal
CAUTION! Risk of damaging the pump!
A mechanical seal must never operate without
fluid and lubrication even for a short period of
time.
Insure that the pump is completely full of water
and vented before starting the pump. Small leaka-
ges can occur during the period of running-in,
they should disappear after several hours of ope-
ration. If the leakages don't stop, shut down the
pump disassemble the mechanical seal and cont-
rol their condition.
8.3.5 Normal shutdown
WARNING! Risk of Burns!
If the fluid temperature and system pressure is
high, close the isolation valves upstream and
downstream of the pump. Initially let the pump
cool.
• Close the delivery valve to reduce the load on the
driving unit.
• Stop the driver of the pump.
• When the pump has come to rest, close the suc-
tion-isolating valve.
• Isolate any ancillary supplies.
8.3.6 Emergency Shutdown
In the event of any malfunction of the equipment,
switch off the pump set. When the pump has
come to rest, close the suction & discharge valves,
isolate the driving unit power supply & rectify the
fault.
WILO SE 10/2019