Self Actuated Pressure Control Valve
Self-actuated pressure control valves serve to maintain an adjustable set-point pressure within certain levels in pipelines or vessels (tanks). They are self-actuating i.e. do not feature additional auxiliary energy such as pneumatic air or electricity to operate. They are preferably used to control the pressure of fluids, gases and vapours in industrial, foodstuffs and pharmaceutical plants.
Self-actuating pressure control valves are the most uncomplicated pressure controllers available. The main advantage associated with this type of valve is that no additional auxiliary energy is necessary for moving the actuator, thus realisation of simple pressure control systems is achieved at relatively low cost.
Self-Actuated Pressure Control Valves, which control pressure at its outlet, are known as Self actuated downstream pressure control valves /Pressure Reducing Valves / Pressure Regulators. These valves regulate its outlet pressure near to the desired set point, irrespective of variation in flow through the valve and variation in inlet pressure.
Self-Actuated Pressure Control Valves, which control pressure at its inlet, are known as Self actuated upstream pressure control valves / Pressure Relieving Regulators / Back Pressure Regulating Valves. These valves regulate its inlet pressure near to the desired set point, by opening in proportion to the rise in inlet pressure above set point. These proportional type regulating valves and application they serve are very different from conventional safety relief valves; which protect the pipe line or equipment from over pressure by popping open. Safety Relief Valves are not meant for continuous proportional control action.
Depending upon the required pressure range & flow capacity of the control valves, either direct acting or pilot operated pressure control valves are used.
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