Series MNKA,
acc. to ASME
Page 8
9250-050-en
Revision 11
TM 7903
Edition 07/2010
During operation of the pump it must be ensured that
excessive deposits of dust are prevented (regular
cleaning) in order to prevent the pump surface from
heating to above the admissible temperature.
The following
Table 1
contains the resultant
theoretical limit values of the temperature of
the liquid medium allowing for the temperature
classes according to European EN 13463-1.
Table 1
Temperature class acc. to EN 13463-1
Limit value of the temperature of the fluid
Lining material
PFA/PTFE
Can material
4)
CFK-F
CFK-H
T6
85 °C (185 °F)
not certified to ATEX
T5
100 °C (212 °F)
T4
135 °C (275 °F)
125 °C (257 °F)
1) 2)
125°C (257°F)
1) 2)
T3
200 °C (392 °F)
150 °C (302 °F)
180 °C (356 °F)
3)
T2
300 °C (572 °F)
150 °C (302 °F)
180 °C (356 °F)
3)
T1
450 °C (842 °F)
150 °C (302 °F)
180 °C (356 °F)
3)
1) Long life grease lubrication : no restriction.
Oil bath lubrication: standard version with shaft seal
T3
labyrinth seal (special design)
T4
.
2) The limit values specified for the temperature of the fluid at the
pump inlet are determined for the most unfavourable case (high
speed, low flow, low heat capacity of the medium, ....). Under
favourable operating conditions the limit values specified may
be increased by up to 5 K after consultation with the manu-
facturer.
3) Consult the manufacturer for higher limit values.
4) The can material has been list in the data sheet.
The plant customer must ensure that the
prescribed operating temperature is observed.
The maximum admissible temperature of the
liquid medium at the pump inlet depends on the
temperature class and the selected lining material
required in each case.
Observance of the temperature class T4 with oil
bath lubrication is not possible with the standard
shaft seal. A labyrinth seal must be used instead
of the shaft seal for the temperature class T4 and
with oil-lubricated rolling bearings.
2.6.8 Maintenance
For safe and reliable operation, it must be
ensured with regular inspection intervals that
the unit is properly serviced and kept in a
perfect technical condition.
Example: Functioning of the ball bearings. The mode
of operation and operating conditions largely
determine the actual service life that can be attained.
Regular checks of the bearings and their running
noise can prevent excess temperatures due to hot-
running bearings, collision of the outer magnet
assembly against the lantern or even defective
bearing seals. See
Section 7.2
.
In regard to media containing solids, the maintenance
intervals must be set by the operator in accordance
with the conditions of operation.
If auxiliary systems (e.g. external flushing, cooling,
heating) are installed, a check must be made to see
whether monitoring facilities are required to safeguard
their operation.
2.6.9 Electric peripheral equipment
Electric peripheral equipment, e.g. pressure,
temperature and flow sensors etc. must
comply
with
the
prevailing
safety
requirements and explosion protection provisions.
