Richter RMA-B Series (ASME) - Manual (Page 8)

Series RMA-B close-coupled design Page 8
9475-055-en Revision 14
TM 8256 Edition 06/2011
2.6.7 Temperature limits
In the normal operating condition the highest
temperatures are to be expected on the
surface of the pump housing.
In the case of liquids >40 °C (>104 °F) the surface
temperature of the pump housing is generally lower
than the temperature of the liquid as the plastic lining
has an insulating effect.
If the pump is heated (e.g. heating jacket), it
must be ensured that the temperature
classes prescribed in the annex are
observed.
The non heated pump surface must have free contact
with the environment.
When operating the pump, make sure that
an excessive deposit of dust is avoided
(possibly regular cleaning). This prevents the
pump surface from heating to above the admissible
temperature.
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.
The following always applies: No inadmissible
temperatures may be introduced into the motor and
the specifications of the motor manufacturer must be
observed.
The temperature limits of the fluid given in Table 2
only apply when motors are used where the motor
manufacturer permits at least the following
temperatures for the motor flange and motor shaft:
Table 1
Temperature
class
Motor flange Motor shaft
T6 70 °C(158 °F) 70 °C(158 °F)
T5 70 °C(158 °F) 80 °C(176 °F)
T4 75 °C(167 °F) 85 °C(185 °F)
T3 75 °C(176 °F) 85 °C(212 °F)
T2 75 °C(176 °F) 85 °C(212 °F)
T1 75 °C(176 °F) 85 °C(212 °F)
At the same time the specified max. admissible
ambient temperature of 40 °C must not be exceeded.
Table 2 below indicates the admissible medium
temperature, depending on the pump design, as a
function of the temperature class in accordance with
EN 13463-1.
Table 2
Temperature class
acc. to EN 13463-1
Limit value of the
temperature of the liquid
PFA
T6 85 °C (185 °F) 75 °C 1) (167 °F)
T5 100 °C (212 °F) 90 °C 1) (194 °F)
T4 135 °C (275 °F) 150 °C (302 °F)
T3 200 °C (392 °F) 150 °C (302 °F)
T2 300 °C (572 °F) 150 °C (302 °F)
T1 450 °C (842 °F) 150 °C (302 °F)
1) 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, ....).
Under favourable operating conditions the limit values specified
may be increased by up to 5 K after consultation with the
manufacturer.
In the case of motors with the type of protection
"increased safety", no or low temperature entries are
generally permitted for the motor shaft and motor
flange related to an ambient temperature of 40 °C
(104 °F).
In these cases the max. admissible medium
temperature is 20 K above the temperature which may
be introduced into the motor.
e.g.:
Max. motor shaft temperature: 60°C (140 °F)
Max. motor flange temperature: 65°C (149 °F)
This results in a maximum medium temperature for
the pump of 80 °C (60 °C + 20K)
(176 °F (140 °F +20K)).
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.
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. cooling, heating) are
installed, check to see whether monitoring facilities
are required to ensure their function.
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.
Regular checks of the motor bearings in accordance
with the operating manual of the motor manufacturer.
Observe ATEX notes.