Scotch Yoke Direct Gas Actuator

RTQD double acting direct gas actuators, are suitable for the operation of quarter turn valves (ball valves, butterfly valves and plug valves) for on-off and modulating heavy-duty service.

The actuator is made up of a waterproof scotch yoke mechanism transforming the linear movement of the pneumatic cylinder (on closing or opening) into the rotary movement, which is necessary for valve operation. Scotch yoke mechanism centerbody cover is machined to provide the assembly pattern for any required accessories (for example positioner, signaling limit swiches, etc.) by mean of proper matching units. The above mentioned accessories are operated by the actuator drive sleeve.

Actuator centerbody bottom wall is machined with threaded holes to allow actuator mounting on top of valve top-work either directly or, when required, with the interposition of an adaptor flange or a mounting bracket. The travel stroke is adjustable between -4 deg/+4 deg at both ends by mean of the external mechanical stops arranged into the side-wall of the mechanism body and into the end flange of the pneumatic cylinder.

Actuators are equipped with an hydraulic cylinder, mounted on the opposite side of the gas operated cylinder, to move the valve in absence of the fluid power by means of an hand pump mounted on the control cabinet.

Technical data

Design pressure

85 or 114 bar depending on the application

(special version available on request)

Standard operating temperature

-20°C to 100°C

(lower or higher temperature on request)

Output torque

From 12.000 Nm up to 500.000 Nm




PED 2014/68/EU

ATEX 2014/34/EU 

EAC TR TS 012/2011 


IP66/67M according to IEC/EN 60529 

SIL3 certified (IEC 61508) as a “single device”

Designed and tested in accordance with EN 15714-4

(further certifications are available, please contact us for updated list)

Contact us for more information