ProMinent Sigma / 2 Basic S2Ba, Руководство по эксплуатации

Страница: 35 / 88

CAUTION!
Danger due to incorrect use of the integral relief valve
The integral relief valve can only protect the motor and
the gear, and then only against impermissible positive
pressure that is caused by the metering pump itself. It
cannot protect the system against positive pressure.
–
Protect the motor and gear of the system against
positive pressure using other mechanisms.
– Protect the system against illegal positive pressure
using other mechanisms.
Warning of feed chemical spraying around
n
If no relief valve has been connected to the overflow line, the feed
chemical then sprays out of the hose connection as soon as the relief
valve opens.
n
An overflow line must always be connected to the integral relief valve
and be fed back to the supply tank or - if required by the regulations -
into a special tank.
Crack formation
n
Cracks on the PVT liquid end can occur if a metal overflow line is con‐
nected to the relief valve.
n
Never connect a metal overflow line to the relief valve.
Failure of the integral relief valve
n
The integral relief valve no longer operates reliably with feed chemi‐
cals that have a viscosity of greater than 200 mPa s.
n
Only use the integral relief valve with feed chemicals that have a vis‐
cosity of up to 200 mPa s.
Leaks
n
Feed chemical which remains in the overflow line at the relief valve
can attack the valve or cause it to leak.
n
Route the overflow line with a continuous slope and moreover with the
hose sleeve pointed downwards - see Fig. 17.
The bleed function is blocked if the overflow line is fed into the suction line.
Therefore lead the overflow line back into the supply tank.
When operating the integral relief valve close to the
opening pressure, a minimal overflow into the overflow
line can occur.
Unnoticed diaphragm rupture
n
If the pump has been ordered with an electric diaphragm rupture
sensor, then the diaphragm rupture sensor must also be installed.
n
Screw the enclosed diaphragm rupture sensor into the liquid end.
Unnoticed diaphragm rupture
n
From approx. 2 bar back pressure, the system will emit a signal in the
event of a diaphragm rupture.
n
You should only rely on the diaphragm rupture sensor for back pres‐
sures over 2 bar, or install a back pressure valve and set it to a min‐
imum of 2 bar, if the installation permits this.
P_SI_0023
Fig. 17: Permissible alignment of the relief
valve
Diaphragm rupture sensor
Installation, hydraulic
35