Mounting and installation
6.3.1
Installation examples
Hydraulic Installation
In the case of media which tends towards sedimentation, the base suction
valve or the foot valve of the suction line or the suction lance must be
mounted above the anticipated sediment layer.
Term definition: Siphoning
Siphoning refers to the maximum fluid level (in this case the supply
container) being higher than the lowest point in the metering line. In this
process, the fluid runs out of the metering line without any pump output and
solely via what is known as the "hydrostatic pressure equalisation".
CAUTION!
When connecting the suction and charge pipe, make sure that the O-rings
are mounted on the connections in order to achieve the necessary sealing.
Installation example 1
B
C
1
D
CAUTION!
Neither the overflow line nor the vent line is permitted to be fed back into
the suction line of the metering pump!
417102276 Rev. 5-02.2020
2
The metering pump should ideally be positioned on or over the metering
3
container (pos. A).
A positive pressure difference of at least 0.1 MPa (1 bar) must exist
between the back-pressure at the injection point and the pressure at the
metering pump (pos. B). If this is not the case, a pressure-retention valve
(pos. 2) must be installed in the metering line.
A
In addition, the installation of an appropriate safety overflow valve (pos. 3)
must be installed to prevent unacceptably high levels of pressure in the
metering line.
This valve's overflow line should be fed back into the container in a
depressurised state.
A spring-loaded injection, or metering valve (pos. 1) should be installed at
the injection point (pos. C) (including with supplying metered amounts into
depressurised systems).
For easy venting of the metering pump, the vent connection should be
routed via a separate line back to the metering medium container (Pos. D).
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