These are self operated upstream pressure regulating control valves, used in many applications for limiting pressure buildup (i.e. prevent overpressure) at its location in the pressure system. The valve opens in proportion to the inlet pressure preventing a rise of internal pressure in excess of a specified value.
These valves are used on a wide range of applications in the chemical process industry for up-stream pressure control, eg: Refineries, Fertiliser and Petrochemical Plants, Pharmaceutical and Food Processing Plants.
Principle of Operation
The upstream pressure is registered under the diaphragm opposing the spring when the upstream pressure reaches the set point, the spring is compressed allowing the valve plug to open and relieve excess.
Reference : Valve Solutions