Sera 409.2 ML Series, Руководство по эксплуатации, Страница: 19 / 36

Multi-layer diaphragm pump
Serie 409.2 ML
Operating instruction
TA 431 Rev. 8 en 06/2015
Technical modifications reserved!
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19
In order to avoid cavitation, overloading and excessive deliv-
ery, the following points should be noted:
•
avoid high suction heights
•
keep pipes as short as possible
•
choose sufficiently large nominal diameters
•
avoid unnecessary choke points
•
install a pulsation damper
•
install a pressure relief
•
install a pressure keeping valve, if necessary
•
in the case of degassing media, provide for a supply
CAUTION!
The operator must take suitable precautions on the supply
side (collecting tray, diaphragm rupture alarm) to ensure
that the container does not run dry in the event of a
diaphragm rupture.
8.1.1 Provide for an overpressure protection
if the permissible pressure in the pump head may be exceed-
ed, e.g. when a shut-off valve is closed or if the line is blocked:
•
install the overflow valve
When using an external relief valve the following is valid for the
feed back pipe:
•
lead the overflow line with descending gradient in the
storage tank which is under atmospheric pressure or lead
it in an open drain gutter (see Fig. 20).
•
or connect the overflow line directly to the pump suction
line, but only if there is no check valve inside the suction
line (e.g. foot valve of a suction lance) (see Fig. 21).
CAUTION!
Shut-off valves must not be closed when the pump is
operating!
CAUTION!
An overpressure protection (e.g. an overflow valve)
should always be installed if the permissible operating
pressure may be exceeded.
CAUTION!
In the case that the pump is not equipped with an
overpressure protection, it may get damaged if the
permissible operating pressure is exceeded.
CAUTION !
The pumped medium may spout out if the pump is dam-
aged.
Diaphragm relief valve
Pressure line
Feedback pipe
Shut-off fitting
Tank
Multi-layer-
diaphragm pump
Suction line Shut-off fitting
Fig. 20 Installation with diaphragm relief valve (into tank)
Diaphragm relief valve Pressure line
Feedback pipe Shut-off fitting
Multi-layer
diaphragm pump
Suction line Shut-off fitting
Fig. 21 Installation with diaphragm relief valve (into suction line)