Critical Technical Advantages
-
Nuclear-Qualified Reliability: The NS designation signifies that this actuator is built and documented for nuclear service. It features the structural integrity and material traceability required for safety-related loops, including seismic resilience and corrosion-resistant protection.
-
Optimized Thrust for Precise Control: Capable of producing maximum thrusts up to 5.3 kN (1,200 lbf), the 656 NS provides the ideal balance of power and sensitivity. This makes it perfect for modulating airflow and steam valves where over-sized actuators would be inefficient.
-
Versatile Bracket and Plate Mounting: The base of the 656 NS is equipped with four tapped holes, allowing for seamless installation via bracket or plate mounting. This versatility simplifies the automation of non-standard dampers and built-in turbine valves during plant upgrades or retrofits.
-
Adaptable Stroke Range: With strokes available up to 105 mm (4 1/8 inches), the actuator accommodates various travel requirements for both sliding-stem and linkage-driven equipment, ensuring full-stroke modulation and tight shutoff.
-
Rugged Seismic Stability: Featuring a thick-walled yoke and casing construction, the 656 NS is engineered to maintain its setpoint even under high-vibration or seismic conditions. The rugged design protects internal components from deformation and atmospheric corrosion.
-
Manual Override Capability: For emergency operation or manual testing, the 656 NS is available with a top-mounted handwheel. This allows operators to maintain control of critical systems even in the event of a total loss of pneumatic supply air.
Technical Performance Matrix
| Feature | Details |
| Actuator Type | Direct-Acting Pneumatic (Nuclear Service) |
| Max Thrust | 5.3 kN (1,200 lbf) |
| Stroke Capacity | Up to 105 mm (4 1/8 inches) |
| Mounting Logic | Bracket or Plate (4-hole base) |
| Materials | High-grade Cast Iron and Steel |
| Manual Operator | Optional Top-Mounted Handwheel |
Primary Applications in the Nuclear Sector
-
HVAC Containment Dampers: Precise airflow management in reactor containment and auxiliary buildings.
-
Turbine Steam Valves: Reliable operation of built-in valves for secondary side steam control.
-
Safety-Related Louvers: Automation of ventilation systems required for emergency cooling and air filtration.
-
Linkage-Operated Mechanisms: Providing linear thrust for various seismic-qualified mechanical systems.
