The control valve plays an important role in the loop adjustments, in the automatic control of industrial processes.
Performs the function of varying the flow of control fluid, which modifies the value of the measured variable, behaving like a continuously variable area orifice.
Within the control loop is as important as the primary element, the transmitter and controller. The shutter control performs the function of fluid flow, acting in the direction of its axis.
Shutter equal percentage:
In a shutter with equal percentage characteristic, every increment of stroke in the shutter produce a change in the flow that is proportional to the one that flowed before the change.
Valves with isopercentual shutter are used for:
• Fast processes.
• When the system dynamics are not well known.
• When high range flow control is needed(rangeability) * * The "Rangeability" or field of flow control that valve is capable to regulate maintaining the inherent characteristic curve.
Globe Valve: Valve whose construction is distinguished by controlling the flow through a linear movement.
Valve with single seat and 2 ways.
Single seat valves require a larger actuator for closing the shutter against the differential pressure of the process.
The tight closure is achieved with stainless steel shutter and PPL seat.
Normally Closed Control Valves (Spring Return)
Drive: pneumatic (air to open) Features:
Body material: ASTM A216 WCB
Connection: ASME B 16.5. ANSI Class 150.
Limit of pressure: Water 19 bar at 100ºC
Steam 13 bar at 200ºC
Working Temperature: -20ºC / + 230ºC
Features of Actuator: Diaphragm type.
Maximum input pressure: 6 bar. Option: signal 4-20 mA with electro-pneumatic positioner.
Sealing: DIN EN 1349 Class VI (zero leakage)
