The MSD-III is a pneumatic diaphragm actuator with a robust rolling diaphragm and multi-spring design. Available in direct acting (DA) and reverse-acting (RA). Fail open and close are achieved by the multi-spring force or compressed air. Additionally, the rugged one-piece cast yoke, pressed diaphragm case and special nylon-reinforced diaphragm provide dependable high force actuation performance. The MSD-III is available in five sizes to cover a wide range of applications. A manual handwheel is an optional extra on both direct-acting (DA) and reverse-acting (RA) actuators as an option.

  • Multi-spring design- – Excellent long-term accuracy and fail mode reliability are achieved through the multiple spring design with high compression force.
  • Rugged one-piece yoke- – Provides maximum strength and rigidity.
  • Diaphragm case- – Pressed steel case provides high mechanical strength and protection in the event of over-pressurisation. Further reinforcements are provided for actuator sizes greater than 290 to ensure safe operation.
  • Thrust & stroke capability- – Two actuator types and five sizes allow a wide range of applications.
  • Diaphragm- – Moulded elastomer with fabric insert for strength, long life and high sensitivity. The precisely formed diaphragm eliminates any friction and reduces variations in the effective areas during linear operation.
  • Various air connection sizes- – Various air connection sizes provide various accessory applications.
  • Linearity- – The moulded rolling diaphragm and deep cases minimise area change and provide a linear relation between travel and air pressure.
PD Flowtech