Richter MNK Series - Manual (Page 16)

Series MNK 200-150-315
Page 16
9230-053-en Revision 12
TM 8195 Edition 03/2011
7 Maintenance
7.1 Screw connections of the
housing
After initial loading by the operating pressure and
operating temperature the tightening torques of all
connection screws must be checked at the following
points:
housing flange
suction flange
discharge flange
See also Section 6.1.1, para. 1.
Other inspections are to be performed regularly,
depending on the operating requirements.
7.2 Bearing pedestal
The temperature of the bearing pedestal is
not to exceed more than 70 °C and under no
circumstances 80 °C.
At higher temperatures, call in qualified staff without
delay. If this is not possible, the pump must be shut
down and taken out of service.
In many cases it is also recommended to measure
vibration in order to detect bearing wear in good time
7.2.1 Long-life grease lubricated rolling
bearings
Grease fill bearings of the series 2RS are installed as
standard features. The grease is lithium-saponified.
The admissible temperature range is – 30 °C to
+ 110 °C.
The rolling bearings are designed for an L10 service
life of >17,500 hours. The service life of the grease
filling guaranteed by the bearing manufacturers is
given in the following table.
Size Bearing size > Service life
Group 4 6314-2RS / 15000 hr*
* at bearing temperature <50 °C
at bearing temperature 70 °C approx. 7500 hr
If the pump is serviced, it is recommended to also
replace the bearings as a precaution.
In potentially explosive works it is
advisable to monitor the condition of
the rolling bearings
7.2.2 Regreasable rolling bearings
Optionally, the bearing pedestal can be provided with
regreasable rolling bearings. In this case there are
grease nipples on the bearing pedestal by means of
which regreasing must be performed both initially and
every 5000 hours of operation.
For this purpose we recommend the use of 100 cm 3 of
SKF lubricating grease type LGWA 2.
Mixing with other lubricants should definitely be
avoided.
The bearing service life is >17,500 hours of operation
assuing proper lubrication.
7.2.3 Oilbath lubrication
The temperature of the bearing pedestal is
not to exceed more than 70 °C and under no
circumstances 80 °C.
If higher temperatures do occur, call in qualified staff
without delay. If this is not possible, the pump must be
shut down and taken out of service.
In many cases a vibration measurement is
recommended to detect bearing wear in good time.
With an expected bearing temperature of about 70°C
we recommend a mineral oil with the following
characteristics:
Viscosity index : approx. 85
Kinematic viscosity at 40°C : approx.
s
2
mm 40 . ca
A fully synthetic gear oil to ISO VG 220 is to be used
for temperatures below – 20 °C.
Replacing the bearings: The rolling bearings are
designed for an L
10
service life of >17,500 hours.
We recommend 17.500 working hours respectively
every 3 years a change of bearing should be made.
Oil changes: 1x per year at bearing temperatures up
to 50 °C.
Every 6 months at bearing temperatures up tot 70 °C.
At higher temperatures more frequently in accordance
with the regulations.
When the pump is serviced, it is recommended to
replace the bearings and shaft seals as a precaution
and to pour in fresh oil.
Oil level check: The oil level is to be regularly
checked on the constant level oiler 638/1 to ensure
safe operation.
It must be ensured that there is always oil in the
constant level oiler; it must under no circumstances be
completely drained.
In potentially explosive works it is
advisable to monitor the condition of
the rolling bearings
If there is a suspicion that splash water could have
entered the bearing pedestal, the oil must be replaced
immediately. Even small amounts of water in the oil
reduce the service life of the rolling bearings to a
fraction of the normal service life.