Product Overview
The AIR TORQUE AT251U S12 B is a high-performance pneumatic rotary actuator engineered for precise quarter-turn valve and damper automation in demanding industrial process environments. Manufactured by AIR TORQUE, a globally recognized brand in rack-and-pinion pneumatic actuation technology, this actuator converts compressed air energy into controlled rotary torque through a precision-machined rack-and-pinion mechanism. The AT251U series is designed for direct mounting to ball valves, butterfly valves, and plug valves, providing reliable open/close or modulating operation within process control loops. Its compact extruded aluminum body, dual-piston configuration, and standardized mounting interface make it a direct-fit solution for both new installations and OEM replacement applications across the process, energy, and manufacturing sectors.
Technical Specifications
| Parameter | Specification / Feature |
|---|---|
| Component Type | Pneumatic Rotary Actuator (Quarter-Turn Valve Actuator) |
| Model Designation | AT251U S12 B |
| Actuation Principle | Double-acting rack-and-pinion, 90° rotary stroke |
| Operating Pressure | Standard Industrial Grade (2 to 8 bar / 30 to 120 psi) |
| Supply Medium | Filtered, dry or lubricated compressed air (ISO 8573-1) |
| Rotation Angle | 90° standard (adjustable ±5° at both end stops) |
| Mounting & Connection | Standard ISO 5211 top mounting interface; NAMUR air port pattern |
| Body Material | Anodized extruded aluminum alloy housing |
| Sealing | NBR (Buna-N) O-rings and guide bands |
| Temperature Range | -20°C to +80°C standard (NBR seals) |
| Position Indication | Integrated visual position indicator with NAMUR slot for accessories |
Engineering Features & Advantages
- Precision Rack-and-Pinion Performance: The dual-piston rack-and-pinion design delivers balanced, backlash-free torque transmission with a constant output torque curve throughout the 90° stroke, ensuring accurate and repeatable valve positioning.
- Industrial Reliability: Constructed for continuous duty with durable, corrosion-resistant materials and proven engineering for maximum system uptime.
- Direct Fit Replacement: Precision-manufactured to original AIR specifications for direct replacement, minimising downtime and eliminating fitment issues.
Typical Industrial Applications
Its compact extruded aluminum body, dual-piston configuration, and standardized mounting interface make it a direct-fit solution for both new installations and OEM replacement applications across the process, energy, and manufacturing sectors.
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AIR TORQUE AT251U S12 B Pneumatic Rotary Actuator
⚡ Emergency Plant Maintenance & Ready-to-Ship Notice:
- Authentic & Fully Tested: 100% bench tested for hydraulic response, pressure rating, and null-bias stability before dispatch.
- Fast Dispatch: In-stock units ready for same-day dispatch via DHL / FedEx Express directly to your plant.
- Pre-Shipment Verification: High-definition photos, video testing runs, and serial number verification provided prior to shipment.
- Peace of Mind: Covered by our 12-Month Replacement Warranty.
Shop the genuine AIR TORQUE AT251U S12 B Pneumatic Actuator. This Italy-made rack and pinion actuator features double-acting design, delivering reliable torque for quarter-turn valves in heavy-duty industrial systems.