Rotork Skilmatic SI electro-hydraulic fail-safe actuator, SIL 2/3, part-turn and linear

Rotork Skilmatic SI combines the simplicity of electric power, the precision of hydraulics and the reliability of mechanical spring or accumulator return. The self-contained unit requires no external hydraulic power unit.

SI3 is a compact spring-return actuator for ball, butterfly and plug valves and dampers, part-turn torque approx. 75–36,000 Nm. SI4 is designed for high torque and thrust, with accumulators for multiple reserve strokes and higher speed, part-turn torque up to 200,000 Nm. Linear versions provide thrust up to 400 kN.

1-phase, 3-phase or 24 V DC supply. Fail-safe action: close, open or stay put. ESD/PSD, partial stroke test, 4–20 mA positioning with approx. 0.3 % resolution. Certified to IEC 61508, Systematic Capability SC-3, suitable for SIL 2 and SIL 3.

Key features:

• Fail-safe by spring or accumulator
• SI3: 75–36,000 Nm; SI4: up to 200,000 Nm; linear up to 400 kN
• IEC 61508, SC-3, SIL 2/3
• ESD/PSD and partial stroke test
• 1ph / 3ph / 24 V DC supply, no external hydraulic power unit

Specifications:

• Type: electro-hydraulic fail-safe
• Part-turn torque: SI3 75–36,000 Nm; SI4 up to 200,000 Nm
• Linear thrust: up to 400 kN
• Power supply: 1-phase, 3-phase, 24 V DC
• Duty: on/off and positioning; fail-safe close / open / stay put
• Positioning: 4–20 mA, resolution approx. 0.3 %
• Certification: IEC 61508, SC-3, SIL 2 and SIL 3
• Interfaces: 4–20 mA, ESD/PSD, HART, Profibus, Modbus, Foundation Fieldbus, Pakscan, Bluetooth, RHS
• Design: industrial / Ex per specification

Application: ESD and HIPPS systems, offshore and onshore shut-off valves, critical valves and dampers.

Scope of supply: Self-contained SI3/SI4 actuator; accumulator, RHS and network card per specification.

Before ordering: Before ordering, specify torque or thrust, operating time, spring action direction and SIL level.