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Pneumatic actuator Si-503 ENType A

Edition: 2008-12 50)to optimize control performance and eliminate backlash. The actuators are designed to fit valves and accessories with the ISO 5211 and VDI/VDE 3845.SOMAS actuators have a torque curve corresponding to the torque demand for ball segment, butterfly, and ball valves. Low-friction seals allow for a low starting torque. Single- or dual- cylinder units are used depending on the required torque and air supply pressure. Single-acting actuators are optimised according to compact dimensions. The springs are supplied in a cartridge to reduce the risk of injury and to simplify maintenance.Adjustable travel stops are provided for both open and closed positions. SOMAS actuators are designed for optimal function in control and on/off applications. The type A pneumatic actuators are specifically made to fit the SOMAS range of valves. They can also be used with most 90° rotary valves. The A-DA actuator is double- acting and the A-SC and A-SO actuators are single-acting spring return for fail safe operation.SOMAS offer a patented backlash-free transmission friction coupling (valid for D (spring to close) Type A – SC Single-acting actuator Double-acting actuator Type A – DA Single-acting actuator (spring to open) Type A – SO
Compact designPatented backlash-free torque transmissionLow friction seals Optimized torque curve Standardised connections between valve and accessories