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position. To guarantee its stability, the pump must be screwed appropriately into the
ground.
The system’s piping must not put any force on the dosing pump’s connections or val-
ves.
To avoid backfiring dosing after the process end, an electrical and hydraulically locking
device is provided on the dosing pump.
7.3 Drainage discharge
NOTICE!
Released gases can destroy the dosing pump’s transmission!
The drainage as well as the leakages from the separate chamber must slope down-
wards, i.e. to go in a descent to the collection tank. Under no circumstances is the
drainage pipe to go direct through the lidded receptacle back to the medium; otherwise
the released gases can infiltrate the dosing pump’s transmission. The drainage pipe
must be directed only to a gas free collection tank (in a decline) or it has to be lead
on a decline to a collection funnel over which it then has to end with enough distance
in between. The leakages can then be directed back via the funnel through the tank
cover. Moreover possible leakages are detected with greater ease from the gap to the
collection funnel.
7.4 Pressure sustaining and safety valves
Pressure sustaining valves are accessories for optimizing the dosing process. They are
used:
• to increase the dosing accuracy in the presence of fluctuating back pressure
• with long dosing lines in order to prevent excess delivery, as the accelerated medium
continues moving on account of its own inertia even when the delivery stroke has
already ended.
• to prevent siphoning when the suction pressure is higher than the pressure system.
NOTICE!
