The RPDA Rotary Piston Double Acting Actuator is designed for heavy duty control applications that require optimum performance. The RPDA is typically utilized when applications require a “lock last” failure mode. The RPDA incorporates a “crank-arm” mechanism specifically designed for the rigors of throttling control valve applications. The RPDA can accept high pressure power supply gas up to 500 psig (3447 kPa) enabling the use of smaller actuators or the exclusive Bleed to Pressure System (BPS™) feature.