Multitech 1777.8/7-10 G3 - Manual (Page 22)

Caution
Caution
Left--hand spring Right--hand spring
Shaft
rotation:
anti-clock-
wise
Shaft
rotation:
clockwise
View
towards
the spring-
loaded ring
Caution
Multitec
22
Mechanical seals
Mechanical seals are precision components. The
seat ring and the spring-loaded ring must always
be replaced together, i.e. always replace the entire mechanical
seal.
To ensure trouble-free operation of the mechanical seal, the
seal faces and the tools must be absolutely clean. Mechanical
seals must be installed with utmost care.
The contact faces shall only be cleaned immediately before
assembly takes place. They must not be greasy (grease,
smudges ...) or damaged.
Individual seal components such as O-rings made of EPDM
must never come into contact with oil or grease.
Mechanical seal reassembly is effected in reverse order to
dismantling.
When mounting the spring-loaded ring, we recommend to wet
the shaft protecting sleeve with clean fluid handled.
The seat ring and the spring-loaded ring shall always be
mounted by hand resp. fingers, making sure that pressure is
applied evenly, without tilting.
Horizontal baseplate-mounted pump units
On pump versions C and D, the correct direction
of rotation must be observed for mechanical
seals with uni-directional springs.
Fig. 39
Sealing elements
Sealing elements made of EPDM must never
come into contact with oil or grease.
Defective O-rings (which have sustained mechanical damage
such as cuts, cracks and deformation as well as changes in
properties from deposits or embrittlement) must be replaced.
Gaskets shall always be replaced by new ones.
If possible, the gasket shall be mounted without the use of
mounting aids like grease or adhesives, unless authorized
mounting aids are used.
7.4.3.1 Leakage at the mechanical seal
- Check axial alignment of the seal.
- Inspect gasket 400.1.
- Remove seal cover 471.1 (471.2 for bellows-type seals) and
check position of seat ring in the seal cover.
- Check the O-ring on sleeve 523.1.
- Check O-ring 412.4.
7.4.4
Bearings
Plain bearing
in installation types A - B - E / Ex - F / Fx - V / Vx are re-installed in
reverse order to dismantling.
Rolling element bearings
The rolling element bearings are generally mounted on the
bearing sleeve and tightened with shaft nut 920.2 / 920.6 /
920.7.
They are re-installed in reverse order to dismantling. The
position of the keywayed nuts 920.6 (contact surface = plane
surface with recess) marked during dismantling (7.3.3.2) must
be complied with.
Check the concentricity and face run-out of ring 500.1 with a dial
gauge for variants with oil lubrications.