ProMinent delta DLTa optoDrive Operating Instructions Manual page 78

Repairs
78
11. Pull the dosing head (2) with the screws (1) out of the diaphragm (3)
and completely unscrew this from the drive axle.
12. Remove the backplate (4) from the pump housing (6).
13. Check the condition of the safety diaphragm (5) and replace if nec‐
essary.
14. Push the safety diaphragm (5) onto the drive axle only until it lies
flush with the pump housing (6) and no further!
15. Tentatively screw the new diaphragm (3) onto the drive axle up to
the stop - this must be successful, otherwise the pump will subse‐
quently not meter correctly!
16. Check whether the diaphragm holes align correctly with the pump
housing.
17. If not, start the pump and adjust the stroke length to 100 %.
18. With the pump running, slowly turn the diaphragm (3) in the clock‐
wise direction until the 4 diaphragm holes align correctly with the
pump housing (6). Do not turn anticlockwise!
19. Clamp the diaphragm (3) in this position, adjust the stroke length to
0 % and stop the pump.
20. Unscrew the diaphragm (3) again.
21. Place the backplate (4) onto the pump housing (6).
CAUTION!
– The leakage hole must point downwards in the
subsequent fitting position of the pump - see
figure in the "Maintenance" chapter!
– Place the backplate (4) immediately in the correct
position on the pump housing (6)! Do not twist the
backplate on the pump housing to prevent the
safety diaphragm (5) becoming warped!
22. Place the diaphragm (3) into the backplate (4).
CAUTION!
– Do not over-tighten the diaphragm (3) in the fol‐
lowing step!
– Ensure that the backplate (4) remains in its posi‐
tion so that the safety diaphragm does not
become warped!
23. Hold the backplate (4) firmly and screw the diaphragm (3) in a clock‐
wise direction until it is sitting tightly (the twisting resistance of the
return spring can be felt).
24. Place the dosing head (2) with the screws (1) onto the diaphragm
(3) and the backplate (4) - ensure that the suction connector points
downwards when the pump is subsequently fitted.
25. Gently tighten the screws (1) and then tighten them diagonally. See
below for tightening torque.
26. For types with coarse/fine bleed valve: Allow the cover of the liquid
end to rest in the dosing head, then press the knob of the bleed
valve into the coarse/fine bleed valve.
Check the tightening torque of the screws after 24
hours of operation!