Lutz-Jesco MAGDOS LP, Руководство по эксплуатации

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Hydraulic installation
Hydraulic accessories
22
Solenoid-Diaphragm Dosing Pump MAGDOS LP
© Lutz-Jesco GmbH 2014
Operating Instructions
BA-10231-02-V03
8.7.5 Pressure relief valve
Pressure relief valves have an important safety function for protecting
the dosing pump and the associated pipes and fittings.s The dosing
pump can generate a pressure that is many times the rated one. A
blocked pressure line can lead to dosing medium escaping.
An inadmissibly high pressure can occur if:

the shut-off valves are closed even though the dosing pump is
running,

pipes block.
At an appropriate pressure, a pressure relief valve opens a bypass line
and protects the system in this way from pressures that are too high.
Notes on assembly:

The line for returning dosing medium from the pressure relief valve
must be routed to the dosing tank or to a collecting pan.

The pressure in the dosing tank must not be too high so that it is
possible to accommodate the returned dosing medium.

As an alternative, the system can return dosing medium into the
suction line in front of the dosing pump. In this case, there must not
be a non-return valve or a foot valve in the suction line.

You should install the pressure relief valve as close as possible to
the dosing head.
Fig. 8-12: Installation with pressure relief valve – returning to the suction line
Fig. 8-13: Installation with pressure relief valve – returning to the dosing tank
No. Description
Main line
Injection nozzle with shut-off valve
Pressure relief valve
Chemical tank
Pressure line
MAGDOS LP dosing pump
Wall bracket
Shutoff valve
Suction line
Table 8-2: Designation of components