6 commissioning/shutdown, 1 initial commissioning, 1 filling the pump housing – Richter MNK-B Series User Manual

Page 13: 2 start-up, 2 operating limits, 1 abrasive media, 2 min./max. flow rate, 3 shutdown, Initial commissioning, Filling the pump housing

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Series MNK-B,

close-coupled design

Page 13

9230-055-en

Revision 09

TM 7345

Edition 10/2008

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. When retightening the
housing screws, make sure that the support
bracket is undone. Otherwise, the pump could be
deformed.
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 assemblies.

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.

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