Richter V&A RMI Series, Инструкция по установке и эксплуатации

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Series RMI
Page 8
9430-050-en Revision 00
TM 9886 Edition 03/2018
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 or partially filled state (dry run-
ning). This results in serious damage to
the pump and additional risks to the envi-
ronment can arise.
Dry-running cannot only occur with an insuf-
ficiently 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 con-
tact point shaft seal/shaft, on the inner races
of the rolling bearings and, at high medium
temperatures, on surface of the pump hous-
ing.
In the case of media >40° C the surface temperature
of the pump housing is generally lower than the tem-
perature of the medium as the plastic lining acts as
insulation.
If the pump is heated (e.g. heating jacket), it
must be ensured that the temperature clas-
ses prescribed in the annex are observed.
The not heated pump surface must have free contact
with the environment.
When operating the pump, make sure that
an excessive deposit of dust is avoided (pos-
sibly regular cleaning). This prevents the
pump surface from heating to above the ad-
missible temperature.
Following table below indicates the admissible medi-
um temperature, depending on the pump design, as a
function of the temperature class in accordance with
EN 13463-1.
Temperature class
acc. to EN 13463-1
Limit value of the tempera-
ture of the liquid
PFA
T6
85 °C
not certified to ATEX
T5 100 °C
T4
135 °C
125 °C
1) 2)
T3 200 °C 150 °C
T2 300 °C 150 °C
T1 450 °C 150 °C
1) Grease lubrication : no restriction.
Oil bath lubrication:
standard design with shaft seal T3
labyrinth seal (special design)
T4
2) The limit values specified for the temperature of the medium at
the pump inlet are determined for the most unfavourable case
(high speed, low flow, low heat capacity of the medium, large
magnetic drive ....). Under favourable operating conditions the
limit values specified may be increased by up to 5 K after con-
sultation with the manufacturer.
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.
2.6.8 Maintenance
To achieve safe and reliable operation, it
must be ensured in inspections at regular
intervals that the unit is properly serviced and
kept in technically perfect order.
Example:
Functioning of the rolling bearings. The
mode of operation and operating conditions largely
determine the actual service life that can be attained.
Regular checks of the bearing pedestal area can pre-
vent excessive temperatures due to hot-running rolling
bearings, collision of the drive magnet assembly
against the lantern or even defective bearing seals.
See also 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.