SC - Linear damper actuator


SC is a complete line of linear pneumatic actuators purposely designed and manufactured for the operation of flow control devices such as dampers, louvres, butterfly and ball valves. 
Thanks to their design, they are ideal for applications in power plants, refineries, pipe works and on board vessels. The range of products includes double acting units and are available in different sizes.

You can evaluate the double acting stroking time here


    • Built in lubrication system makes it virtually maintenance free
    • Cylinder can be standard or special strokes
    • Double guide for piston and bushing
    • Excellent response times without need for boosters
    • Full stainless steel version available
    • Light and functional design allows for easy installation
    • No dead volume is left in the actuator chamber in fully open or closed positionsminimising risk of overshoot
    • Suitable for harsh environments such as desert areas and petrochemicals plants


Operating pressure

Pneumatic version up to 10 barg

(special version available on request)

Standard operating temperature

-20°C to 70°C

(lower or higher temperature on request)


Aluminum alloy for Ø 63 to 100

Carbon steel for Ø 125 to 420


Aluminum alloy for Ø 63 to 260

Carbon steel for Ø 330 to 420


Aluminum alloy for Ø 63 to 260

Carbon steel for Ø 330 to 420


Chromium plated alloy steel



PED 2014/68/EU

ATEX 2014/34/EU

EAC TR TS 012/2011

IP66 according to IEC/EN 60529

Further certifications are available, please contact us for updated list.



IMI STI valves, actuators, positioners, SC Series, SC - Linear damper actuator

SC series of actuators is provided with a built-in permanent lubrication system, patented by IMI STI, which assures an extremely smooth valve operation even if dry instrument air is used. Thanks to this lubrication system, which is common to IMI STI linear actuators, no maintenance to moving parts is required, even after many years of continuous service.

The patented lubrication system consists mainly of a grease lubricant filled annular cavity placed inside the cylinder piston, between a sealing ring and a sliding ring to avoid direct contact between the metal surfaces of the piston and the cylinder, even in case of lateral forces acting on the actuator stem. The grease in the annular cavity keeps the metal parts lubricated during piston movement allowing very smooth sliding and a long seal life.