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Series MNK 200-150-315
If the flow rate is too high, the differential pressure
upstream and downstream of the plain bearings could
fall so much that a lack of lubrication or dry-running
may occur.
If the flow rate is too low, the medium may heat up so
much owing to the fluid friction that the max.
admissible surface temperature of the relevant
temperature class is exceeded.
Overloading, overheating, non-observance of the
design data or the incorrect selection of the magnetic
drive can lead to the decoupling of the inner and outer
magnet assemblies. As a result, eddy currents may be
induced on the inner and outer magnet assemblies
and an inadmissible temperature rise may occur.
Provide appropriate monitoring facilities. See Section
5.6.
The plant NPSH value (NPSHA) should be minimum
0.5 m higher than the NPSH value of the pump
(NPSHR) to prevent a lack of lubrication or dry-
running of the plain bearings.
2.6.3 Chargeable liquids
For operation with chargeable liquids with a
conductivity <10
for flushing during evacuation if the lining of
the pump is non-conductive. See Section 6.3.
2.6.4 Identification
The identification on the pump relates to the
pump section. A separate declaration of
conformity must be provided for the shaft
coupling and motor and for other attachments as well
as corresponding identification.
Example of the identification of the pump section:
II2GD IIC TX X.
For assembling the pump with components which are
not explosion-protected (e.g. motor, shaft coupling), it
is recommended to mask or remove the "potentially
explosive" identification from the pump component
and, if necessary, from other accessories.
In this case the declaration of conformity applies
without ATEX identification.
At surface temperatures which depend primarily on
operating conditions, DIN EN 13463-1 Chapter 9.3
allows no temperature class or temperature to be
indicated.
The temperature class must be determined by the
operator
in
accordance
"Temperature Limits".
9230-053-en
Revision 12
TM 8195
Edition 03/2011
-8
S/m inert gas must be used
with
Section
2.6.5 Check of the direction of rotation
If there is also a risk of explosion during the
installation phase, the check of the direction of
rotation must under no circumstances be conducted
by briefly switching on the unfilled pump in order to
prevent an inadmissible rise in temperature at the
plain bearings.
We recommend you to only perform a check of the
direction of rotation with the coupling disengaged or
with a rotating field
6.1.2.
2.6.6 Mode of operation of the pump
The pump may only be started with the suction side
shut-off element fully opened and the discharge side
shut-off element slightly opened. Start-up against a
closed check valve is also possible. The discharge
side shut-off element is to be regulated to the
operating design point directly after run-up.
See also Section 5.4.1.
Operation with closed shut-off elements in the
suction and/or discharge lines is not permitted!
There is a risk that even after a short time
high surface temperatures on the pump
housing may occur owing to rapid heating of
the liquid in the pump interior.
A rapid rise in the pressure inside the pump
involves the risk of overloading to the point of
bursting.
The pump must not be in operation in the
unfilled
running). This results in serious damage to
the pump and additional risks to the environment
can arise.
Dry-running cannot only occur with an
insufficiently filled interior but also in the event
of high gas contents in the liquid medium.
Operation of the pump outside the admissible
operating range may also lead to dry-running (e.g.
due to evaporation in the interior).
2.6.7 Temperature limits
In the normal operating condition the highest
temperatures are to be expected at the contact point
shaft seal/shaft, on the inner races of the rolling
bearings and, at high medium temperatures, on
surface of the pump housing.
2.6.7
We would like to point out that the surface
temperature of the pump housing is only
slightly below the medium temperature.
If the pump is heated (e.g. heating jacket), it must be
ensured that the temperature classes prescribed in
the annex are observed.
The not heated pump surface must have free contact
with the environment.
instrument. See also Section
or
partially
filled
state
Page 7
(dry
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