“VALFONTA M2” pressure reducing valves work according to the direct action principle. This means that the upstream pressure reaches the valve and pushes the shaft-piston-plunger ensemble to close automatically.
When the adjustment screw is then turned clockwise, this causes the spring to move so that it activates the diaphragm and closes it, opening the valve until it reaches the required downstream pressure.
Any upstream pressure variations will be absorbed by the compensating plunger and the downstream pressure will be absorbed by the diaphragm.
As far as the installation process is concerned, mounting on horizontal pipes would be preferred, with the actuator at the top.
For steam installations, on the other hand, the actuator must be installed at the bottom and must be accompanied – if the temperature exceeds 125ºC – by a barrel filled with water to protect the diaphragm.