KNF LABOPORT N820.18 EX Instrucciones De Funcionamiento Originales página 104

Servicing
9 Gas ballast
valve
10 Connection
tube
11 Hose
connections
44
Chemically-resistant Laboratory pump N820.18 EX / N840.18
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 cover
(3).
3. Replace the two O-rings on the connection tube (10/Fig.
10).
4. Loosen the internal cap screw (1) on both pump heads.
5. Remove the two pressure plates (2) together with the two
internal cap screws (1).
6. Unscrew the gas ballast (9/Fig. 10) from the head cover
(3).
7. Replace the O-ring on the gas ballast (9/Fig. 10).
8. Screw the gas ballast (9/Fig. 10) into the corresponding
head cover (3) as far as it will go. Then turn it back again
until the surface is oriented upwards.
9. Unscrew the hose connections (11/Fig. 10) from the head
cover (3) using the tool supplied.
10. Replace the O-rings on the hose connections (11/Fig. 10).
11. Screw the hose connections (11/Fig. 10) into the head
cover (3) hand-tight using the tool supplied.
12. Dispose of the replaced O-rings properly.
Translation of Original Operating Instruction, KNF 317428-317425 05/21
10
11
EX