In addition to its current range of actuators for valves, KSB’s Luxembourg subsidiary SISTO Armaturen S.A. presents its new double-acting or single-acting pneumatic actuator from the SISTO-LAP-500 range. The piston actuator has been designed for valves with a linear stem movement.
A special technical feature of the new actuator is a double piston in tandem arrangement used for a variant designed for high actuating forces. This means that two pistons are operated along one rod in separate pneumatic chambers.
The combination of a 500 mm diameter piston and a control pressure of 7 bar in a double-acting actuator design allows actuating forces of more than 250,000 N to be achieved. The pistons are fitted with a disc with single-lip profile joint each. This configuration ensures smooth, low-friction movement. The piston rod is sealed by a U-ring and a scraper ring.
Manual override and a mechanical travel stop for closed and open positions are optionally available. Suitable working media are dry, clean, non-combustible and non-aggressive gases. Upon request, SISTO-LAP-500 is available as a special variant suitable for use at ambient temperatures of down to -40 °C.