Lpg Excess Flow Valve
GENERAL DESCRIPTION OF DM EXCESS FLOW VALVE & EXCESS FLOW VALVE LONG TYPE:
They can be installed on pipe line service and on the container service when it is important to limit the liquid or vapor flow rate. The seat disk (clape) is normally opened by spring force. When the flow rate high enough to create a pressure drop able to produce a force bigger than spring load, the seat will close.
The equalizing of the pressure on both sides of the seat disk is possible as there is a bleed hole. This means that the excess flow valve does not shut off completely and there is always a minimum flow.