Richter RSI Series - Manual (Page 4)

Series RSA , Mechanical Seals, external, single or Page 4
double, type Crane 58U – 58U
9485-060-en Revision 11
TM 8046 Edition 10/2010
4 Commissioning/Shutdown
4.1 Initial commissioning
See installation and operating manual for the series
RSA or RSI.
4.2 Mechanical seals
The design and material combination are specified in
the data sheet.
The proper condition of the components and
the protective facilities must be ensured to
prevent any risk from escaping medium.
The regulations and recommendations of
the mechanical seal manufacturer must
always be observed.
4.2.1 Use in an explosive area
Use in an explosive area means that only
mechanical seals may be employed which
permit observation of temperature.
The operating manual of the respective mechanical
seal manufacturer is an integral part of this general
operating manual. Additionally, it is imperative to
observe the ATEX notes in the operating manual of
the mechanical seal manufacturer.
This permits, amongst other things, the calculation of
the expected surface temperature at the mechanical
seal. The suitability for the permissible temperature
class as per ATEX is hereby given.
CAUTION:
The permissible temperature class of the complete
unit (pump, mechanical seal, coupling, motor) is
determined by the lowest temperature class of the
individual components.
Example: Pump T4, mechanical seal T3,
coupling T4, motor T4
In both cases the unit may only be used in
atmospheres which may ignite above the temperature
class T3, i.e. >200 °C (>392°F).
4.2.2 External single mechanical seal
Pumps fitted with a single mechanical seal must
not be started up before they are filled with
medium. Otherwise the single mechanical seal is
not lubricated and cooled and could be damaged.
Mechanical seal guard mounted?
See sectional drawing Section 7.
4.2.3 Double mechanical seal
type Crane 58U – 58U
A pump fitted with a double mechanical seal must
not be filled with a product before the
pressurisation system provided has been started
up.
Otherwise damage could occur, e.g. opening of the
wetted sealing gap, before start-up.
To guarantee safe operation, the pressure of the
barrier fluid must be 1-2 bar above the pressure of the
process medium at the mechanical seal at Q=0 m
3 /h.
It must be ensured that the barrier pressure does not
exceed the admissible pressure of the mechanical
seal used.
The required barrier pressure can be determined as
follows:
2/3 of the delivery pressure at Q = 0 m 3 /h
+ supply pressure
+ 1 - -2 bar safety margin
The supply pressure is measured in bar at the pump
suction nozzle. If no measuring point is available, the
supply pressure can be calculated using the following
formula.
Using the same formula, the delivery pressure at
Q=0 m
3 /h can be determined with the pump
characteristic curve.
2 , 10
) (kg/dm x (mFS) H
= (bar) p
3
p = supply pressure or delivery pressure
H
= supply height or delivery head
= density
Are the available connections correctly made?
SE - barrier fluid inlet
SA - barrier fluid outlet
See also sectional drawing in Section 7 .
4.3 Improper operations and their
consequences (examples)
Improper operation, even for brief periods,
may result in serious damage to the unit.
In connection with explosion protection,
potential sources of ignition (overheating, electrostatic
and induced charges, mechanical and electric sparks)
can result from these inadmissible modes of
operation; their occurrence can only be prevented by
adhering to the intended use.
For examples, see installation and operating manual
RSA,
Section 6.6 .