8
6. Maintenance
6.1. Precautionary Measures During Mainten-
ance Work
Whenever working on the pump ensure the
motor cannot get switched on.
If necessary, remove pump from the system for
inspection. Before dismantling allow the pump
to cool down.
➡
Only dismantle the pump as far is necessary to effect
repairs.
➡
Use only benzin or the like for cleaning. Do not use
solvents.
6.2. Cleaning And Replacing Valves And
Membranes
Under normal operating conditions, the pump is maintenance
free. The valves and the diaphragms are wear parts. If the
rated ultimate vacuum is no longer achieved, the pump interi-
or, the diaphragms and the valves must be cleaned and the
diaphragms and valves must be checked for cracks or other
damage.
Depending on individual cases it may be efficient to check
and clean the pump heads on a regular basis. In case of
normal wear the lliiffeettiim
mee ooff tthhee ddiiaapphhrraaggm
mss aanndd vvaallvveess iiss >>
1100000000 ooppeerraattiinngg hhoouurrss.
There can be different numbers of washers 17
in each membrane head. Ensure the correct
assignment for mounting when dismantling the
membrane heads. Don’t confuse the washers
17.
6.3. Dismantling The Membrane Head
➡
Allow the pump to cool down before dismantling.
➡
Using an SW 14 key, unscrew direct screw joint (20) of
interhead connection (10) on diaphragm head 1 (see marks
on the housing).
➡
As far as possible place pump on its side so that the head
to be dismantled points up.
➡
Using an SW 3 key, unscrew the four Allan head screws
(11) and remove head cover (12), taking care with the two
valve plates (13) and sealing rings (14).
➡
Remove intermediate plate (15).
➡
Use a small screwdriver to carefully ease out diaphragm
(16) and manually unscrew from the connecting rod (right-
hand thread). Look out for possible washers (17).
➡
Clean all parts with alcohol and examine diaphragms,
valves and seals for possible damage and renew as
necessary. If a new diaphragm is to be fitted, the washers
(17) of the old diaphragm must be used again otherwise
the pump will not attain the required pressure.
CAUTION
CAUTION
6.4. Assembling The Membrane Head
➡
Assemble all parts in reverse order. The connecting rod
should be positioned in the upper dead point when fitting
the diaphragm. Ensure correct positioning of all parts.
➡
Check correct sealing ring seating.
➡
Re-make hose connection and re-tighten direct screw
joint (20).
➡
Test pump for function.
