n
Place the backplate (4) immediately into the correct posi‐
tion on the pump housing (6)! Do not twist the backplate
on the pump housing to prevent the safety diaphragm (5)
from becoming warped!
18. Place the diaphragm (3) into the backplate (4).
Leakage may become apparent at a later stage
n
Do not over-turn the diaphragm (3) in the following step.
n
Ensure that the backplate (4) remains in its position so
that the safety diaphragm does not become warped.
19. Hold the backplate (4) firmly and screw the diaphragm (3) in
a clockwise direction until it is sitting tightly (the twisting
resistance of the return spring can be felt).
20. Set the stroke length to 100%.
21. Place the dosing head (2) with the screws (1) onto the dia‐
phragm (3) and the backplate (4) - ensure that the suction
connector points downwards when the pump is in its subse‐
quent fitting position.
22. Gently tighten the screws (1) and then tighten them cross‐
wise. See below for the tightening torque.
23. With PP types with degassing: Allow the cover of the liquid
end to engage in the dosing head, then press the grip of the
vent valve into the dosing head.
Leakage is possible
n
Check the tightening torque of the screws after 24 hours
of operation.
n
With PP and PV dosing heads, check the tightening
torque again after three months.
Data
Value Unit
Tightening torque for screws:
4.5 ... 5.0 Nm
1
2
3
4
5
6
P_BE_0018_SW
Fig. 18: Partially exploded view of the liquid end
Tightening torque
Repair
49
