Functional Description; Pump; Liquid End; Integral Relief Valve - ProMinent Sigma/3 Basic S3Ba Series Operating Instructions Manual

Functional description

5 Functional description

5.1 Pump

5.2 Liquid end

5.3 Integral relief valve

14
The metering pump is an oscillating diaphragm pump, the stroke length of
which is adjustable. An electric motor drives the pump.
The diaphragm (2) hermetically shuts off the pump volume of the dosing
head (4) towards the outside. The suction valve (1) closes as soon as the
diaphragm (2) is moved in to the dosing head (4) and the feed chemical
flows through the discharge valve (3) out of the dosing head. The dis‐
charge valve (3) closes as soon as the diaphragm (2) is moved in the
opposite direction due to the vacuum pressure in the dosing head and
fresh feed chemical flows through the suction valve (1) into the dosing
head. One cycle is thus completed.
3
4
Fig. 7: Cross-section through the liquid end
1 Suction valve
2 Diaphragm
3 Discharge valve
4 Dosing head
5 Backplate
13 Safety diaphragm
The integral relief valve normally operates as a simple, directly controlled
bleeder valve. The feed chemical then flows out through the hose connec‐
tion, e.g. into a storage tank, as soon as the pressure exceeds the pre-set
pressure value.
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 pres‐
sure.
The integral relief valve works as a bleed valve if the rotary dial is turned
clockwise up to the "open" stop, acting as a priming aid when starting up
the pump against pressure.
5
13
2
1