Series MNK-B,
size 25-25-100
Page 13
9230-056-en
Revision 14
TM 9542
Edition 06/2016
6
Commissioning/Shutdown
6.1 Initial commissioning
Normally, the pumps have already been test-run with
water. Unless special agreements have been made,
there could still be residual amounts of water in the
pump. This must be noted in view of a possible
reaction with the medium.
6.1.1 Filling the pump housing
Check to see whether the screws on the suction
flange, discharge flange, housing flange and drain
flange are tightened.
For screw tightening torques see
Section 1.1
.
Open the suction line fully so that the medium can
flow into the pump.
Open the discharge valve so that the air in the
pump can escape.
If air cannot be vented into the discharge line, e.g.
a drop in pressure in this line is not permitted,
venting must be performed upstream of the
discharge valve.
Monitor the venting operation until no air but only
liquid emerges.
Close the discharge valve again until
only the minimum flow rate is obtained
after the motor has been started.
6.1.2 Start-up
Check the direction of rotation of the
motor with a rotary field instrument.
As viewed from the motor, the direction
of rotation of the pump is clockwise. See also the
direction of rotation arrow
of the pump.
If no rotating field instrument is available, the
motor may also be activated briefly, with the
pump filled, so that it does run up. You can
observe the direction of rotation through the fan hood.
The pump must not run dry during the check
of the direction of rotation.
The pump must be completely filled with liquid.
The maximum admissible flow rate must not be
exceeded.
Otherwise the plain bearings can run dry in
both cases.
Switch the motor on.
Set the desired flow by opening the discharge
valve.
When the motor is running but the pump is not
conveying, this means that the magnetic drive
has stopped.
Switch motor off immediately in order to prevent
overheating of the magnet drive and the back
plate.
Then proceeded as follows:
Close discharge valve down to the position
"minimum flow rate".
Start motor again.
If the magnetic drive stops again, look for the cause.
6.2 Operating limits
The operating limits of the pump/unit in terms
of pressure, temperature, power and speed
are entered in the data sheet and it is
imperative to observe them!
6.2.1 Abrasive media
If liquids with abrasive constituents are
conveyed, increased wear at the pump is to
be expected. The inspection intervals should
be reduced compared with the usual times.
6.2.2 Min./max. flow rate
The operating range generally recommended lies at
0.3 Q
opt
to 1.1 Q
opt
. Consult the manufacturer for
operation outside this range. and observe
Section
2.6.2.
6.3 Shutdown
Close discharge valve down to the position
"minimum flow rate".
Switch motor off.
Close discharge valve completely.
Only close the suction line if the pump is to be
evacuated or dismantled.
For all work on the machine, make sure that
the motor cannot be inadvertently switched
on.
If the pump is to be evacuated or flushed,
observe the local regulations.
If the pump has been operated with a
chargeable liquid, it must be filled with inert
gas (e.g. nitrogen) to prevent an explosive
atmosphere.
It is recommended to wait one hour before the pump
is dismantled from the plant to permit static peak
charges to be eliminated.
These measures are not necessary with pumps with a
conductive plastic lining.
If the pump is returned to the manufacturer's, clean
the pump very thoroughly.
See also
Section 3.1
.
