ALLDOS KM 255, Руководство по эксплуатации

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KM 255 en
22 15.720045-V1.0
Pressure retention valve
With open outflow of the dosing medium or low counter-
pressure:
A positive pressure difference of at least 2 bar has to exist bet-
ween the counterpressure at the injection point and the pres-
sure of the dosing medium at the suction valve of the dosing
pump.
If this cannot be guaranteed:
•
Install a pressure retention valve (7i) directly in front of the
outlet or the injection unit.
Pressure retention valve
To avoid the siphon effect:
• Install a pressure retention
valve in the dosing line and, if
necessary, a solenoid valve
(14i) in the suction line.
Overflow valve
To protect the dosing pump and the pressure line
against:
• Install an overflow valve (6i) in the pressure line.
For volatile media:
• flooded suction
• Install a filter in the suction line to prevent the valves
being contaminated.
To install the suction line:
• Keep the suction line as short as pos-
sible, avoid a tangled suction line
• If necessary, use swept bends
instead of elbows.
• Always lay the suction line rising to
the suction valve of the dosing pump.
• Avoid loops which cause air bubbles.
For easy deaeration of the dosing head:
Install a ball valve (11i) with bypass line (back to the dosing tank)
immediately behind the pressure valve.
In case of long pressure lines:
• Install a check-back valve (12i) into the dosing line.
7i
p
≥
2 bar
14i
p
1
p
2
p
2
- p
1
1 bar
>
_
6i
10i
p
6i
10i
p
11i
12i