SS2-8310-0500-05 OVERVIEW Model VPR pneumatic valve positioner has been designed specifically for FloWing valves (Eccentric Rotary Control Valves).  It enhances the response and other performance characteristics of the valves and minimizes the effect of fluid pressure variation. FEATURES 1)   The VPR is compact and can be readily installed. 2)   All of the major components are housed in the casing and purged with bleeding air, there by preventing corrosion caused by adverse atmosphere. 3)   The VPR has an air booster mechanism.  Although compact, the VPR  provides a rapid response speed which is comparable with that of a large positioner. 4)   The VPR can be effectively used when the controller signal span and the actuator spring span do not mutually conform, so that the valve position can be controlled in direct conformity with the controller signal.