PSV Mitech’s pneumatic rotary actuators offer a choice of either a double crank or a scotch yoke mechanism. The double crank, for modulating control purposes, provides high run torques, low friction and negligible backlash, while the scotch yoke design, for on/off control, ensures high end torques.
The actuators feature square drives allowing them to be mounted perpendicular to, or in-line with, the pipe work. The devices are field reversible from clockwise-to-close to clockwise-to-open permitting base mounting of the actuator irrespective of valve type and fail action.
When the units are operating with a double acting fail action, all the available power is at the shaft, as torque output. Fail action can be obtained by the use of a volume tank and switching valve arrangement. These double acting types are compact, powerful and relatively inexpensive. The range of actuators covers torques up to 250,000Nm.
All units have simple ‘O’ ring pressure seals to reduce maintenance costs, and the adjustable end stops allow the end position to be externally adjusted in both the open and closed positions. Provision has been made to allow either a pneumatic or electro-pneumatic positioner to be mounted with an internal feedback arm, making it easier to convert for modulating duty.
