Diaphragm Vacuum Pumps N 813
Servicing
Translation of original Operating and Installation Instructions, english, KNF 121240-121506 09/19
33
6. Screw the structured diaphragm, complete with diaphragm
spacer(s), into the connecting rod (clockwise) and tighten it by
hand.
e) Changing valve plates and sealing rings
1. Separate the ribbed plate (
3
) from intermediate plate (
2
).
2. Remove the valve plates (
6
) and sealing rings (
7
) from the
intermediate plate.
3. Check that the valve seats, the ribbed plate and intermediate
plate are clean. If scratches, distortion, or corrosion are evident
on these parts they should be replaced.
4. Lay the new valve plates in the recesses in the intermediate
plate. The valve plates for suction and pressure sides are iden-
tical, as are upper and lower sides of the plates.
5. Check that the valve plates are not deformed by moving them
gently sideways in their recesses.
6. Lay the sealing rings on the intermediate plate.
f) Refitting the pump heads
1. Turn the counter weight (
11
) to bring the structured diaphragm
(
8
) to top dead centre.
2. Place the intermediate plate (
2
), with valve plates (
6
) and
sealing rings (
7
), and ribbed plate (
3
) on the housing, in the
position indicated by the markings (
M
).
3. Gently tighten the screws (
4
), evenly and diagonally.
4. Turn the counter weight to check that the pump rotates freely.
5. Now tighten screws (
4
) firmly.
Repeat operations c), d), e), and f) for the remaining pump head
(or heads).
g) Refitting the cover plate
1. Refit the cover plate (
5
) to housing (
1
).
h) Refitting the pneumatic head connection(s)
1. Refit the pneumatic head connection(s).
If you have any questions about servicing, call your KNF technical
adviser (see last page for contact telephone number).
Summary of Contents for N 813.3 AN.29DC-B
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