Modulating process control - steam, water and general process media.
A control valve modulates flow to a proportional setpoint rather than simply switching on or off - the actuator is paired with a positioner that drives the valve to any position between fully open and fully closed in response to a control signal.
We supply pneumatic control valves for steam, water and general process media, sized to line pressure, flow coefficient (Cv) and the specific media being controlled.
Body, trim, actuator and positioner are quoted and supplied as one matched assembly rather than as separate line items, selected together against the same duty point - so the pairing arrives already sized and stroked, instead of being reconciled on site.
Actuated control valve for proportional (modulating) process control, not simple on-off isolation.
IllustrationPneumatically actuated angle-body valve for steam, hot water and process fluid switching - compact, fast-cycling.
Y-pattern globe-style control valve offering lower pressure drop than a standard globe body at full opening.
An on-off automated valve (e.g. an actuated ball valve) only opens or closes fully. A control valve, fitted with a positioner, can hold any intermediate position in response to a 4-20mA or pneumatic control signal - used for proportional process regulation like flow, pressure or temperature control loops.
Yes, and in practice they can only be specified together. The actuator has to deliver enough thrust to seat the trim against the differential pressure at the worst-case duty point, not merely enough to move the stem, so it cannot be chosen until the valve body and trim are fixed. We size and supply the valve, actuator and positioner as a single assembly against one duty sheet.
Usually yes - “automatic” is normally being used to mean the valve is actuated rather than hand-operated, which is what this page covers. It is worth separating it from a self-operated regulator, which holds a setpoint from line pressure alone with no control signal and no air supply. If that is what the duty needs, send us the setpoint and the medium and we will quote a regulator instead.
Send the duty, media and sizing you have - we target a quote inside 24 hours.
