KNF LABOPORT N820.18 Originalbetriebsanleitung Seite 112

Servicing
9 Gas ballast
valve
10 Connection
tube
11 Hose
connections
48
Replacing the diaphragm
On the pump, the diaphragms (7) are changed succes-
sively to ensure that the shim rings (8) are used in the
same quantity as previously.
1. Press down one diaphragm (7) so that the other di-
aphragm is in the upper change point.
2. Carefully turn the upper diaphragm (7) counterclockwise
by hand and remove it.
Make sure that the shim rings located between the di-
aphragm and connecting rod do not fall into the pump
housing.
Remove any shim rings stopping on the diaphragms and
fit them on the associated connecting rod thread.
Prerequisite for ensuring the pneumatic performance of
the pump is that the same number of shim rings be
mounted as before.
3. Screw in the new diaphragm (7) by hand and tighten it by
hand.
4. Perform steps 1 – 4 for the second pump head.
5. Dispose of the replaced diaphragms (7) properly.
Changing O-rings
9
Fig.10: Changing O-rings
1. Pull the two pump heads apart.
2. Pull the connection tube (10/Fig. 10) out of the head plate
(3).
Translation of Original Operating Instruction, KNF 317428-317425 02/23
Chemically-resistant Laboratory pump N820.18 / N840.18
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