Richter Mechanical Seals - Manual (Page 4)

Series SCK , mechanical seals with quench Page 4
9220-012-de Revision 01
TM 6478 Edition 04/2006
4.3 Inadmissible modes of
operation and their
consequences (examples)
Inadmissible modes of operation, even for a short
time, can 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) may 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
SCK, Section 6.6.
5 Maintenance
The regulations of the mechanical seal
manufacturer must always be observed.
See also the installation and operating manual
for the SCK series.
Any quench fluid which has escaped must be
replenished in good time.
A difference is made between open and closed
quench systems.
It must be ensured with closed systems that the filling
level is always adequate. The quench fluid can
become enriched with the process medium through
leaks. It is therefore to be completely changed from
time to time in line with the operating requirements.
If the filling level of the quench fluid has risen
in a storage container provided, it must be
replaced immediately. If the filling level of the
quench fluid has risen in a storage container provided,
it must be replaced immediately.
5.1 Dismantling stationary,
single mechanical seal RG-4,
with quench
Dismantling can be checked using the sectional
drawings in Section 7 and Section 9 of the
installation and operating manual SCK as well as the
components available.
5.1.1 Dismantling of impeller, back plate
and RG-4
First of all relieve the mechanical seal by undoing
the attachment screws 901/5.
Undo screws 901/6 and washers 554/6 of the
bearing pedestal / back plate.
Move the back plate almost up to the impeller with
light hammer blows.
Bearing pedestal group 3:
The labyrinth disc 555 must be secured
with two bolts prior to the dismantling of
the impeller. For this purpose there are 2
bores Ø5mm in the bearing pedestal. The
mechanical seal is pressure-relieved as a result.
See dismantling in Section 7.7.1 and 7.7.5 in the
installation and operating manual SCK.
Undo impeller 230 with a strap wrench or
assembly wrench. Right-hand thread! Press off
the housing cover in the direction of the impeller.
For assembly aid for impeller, see Section 10.1 in
the installation and operating manual SCK.
With some pump sizes the work sequence is to be
repeated once or twice so that the cup springs
950/1 can be completely relieved.
Then completely remove the impeller 230. Remove
the mating ring 475/1 and the flat gasket 400/1.
Remove back plate (for sequence, see Sections
4.2.1 and 7.7.4 in the installation and operating
manual SCK) with centering ring 511, O-ring
412/3, seal face 472/1 and intermediate ring 509.
Pull the entire rotary ring carrier, comprising the
parts rotary ring carrier 485/1, stud 560/1, spring
477/1, thrust ring 474 and O-ring 412/5 out of the
seal housing 483.
5.1.2 Dismantling of shaft sleeve
Pull the shaft sleeve 524 with the rotating unit
470/1 which is still installed off the shaft.
For changing the rotating unit, undo the setscrew
904/2 (depending on the design of the shaft
sleeve) and pull it off the shaft sleeve 524.
Observe the operating manual of the mechanical
seal manufacturer.
Remove seal housing 483.
Remove mating ring 475/2.
If plastic bearing points of the mating ring 475 or of
the shaft sleeve 524 are destroyed, they can be
renewed by the pump manufacturer.