We manufacture standardized pneumatic rotary actuators in double-acting and spring-return builds. All units feature standard ISO 5211 and NAMUR interfaces for fast, direct mounting. For long-term reliability, our heavy-duty internal design lasts for 1 million cycles. It delivers zero torque degradation over time, ensuring your safety margins.
Hearken Rotary Pneumatic Actuators are quarter-turn pneumatic actuators manufactured by Hearken Co., Ltd. (Wenzhou, China). The HPA series includes rack and pinion models from 14 Nm to 8,000 Nm, and The HPAC and HPA-G Series Scotch-yoke models up to 250,000 Nm, all conformant with ISO 5211 mounting interface and NAMUR VDI/VDE 3845 accessory pad. Available in double-acting and spring-return, ATEX/SIL /CE/IP67 and EAC certifications are approved. Hearken actuators serve ball valves, butterfly valves and plug valves in oil & gas, petrochemical, water treatment, food & beverage, marine and HVAC applications across 105 countries.
The pneumatic rack and pinion rotary actuator features a heavy-duty mechanism. It ensures high-precision angular stroke and zero-backlash performance. This design is ideal for critical automation.
This 90 degree pneumatic rotary actuator is optimized for quarter-turn ball and butterfly valves. It delivers a formidable torque output up to 8000 Nm. It easily handles high-pressure industrial flow control.
This rotary pneumatic actuator 90 degrees equips a high-visibility 3D position indicator. It allows real-time monitoring of valve status. This feature prevents operational errors from incomplete rotation.
This customized long shaft pneumatic actuator features an extended drive shaft for specialized mounting. A top-mounted visual indicator complements the build. It ensures precise on-site verification.
Designed specifically for Y-pattern 3-way valves. It provides precise 120-degree travel for smooth media diverting without requiring complex mounting brackets.
Provides 135-degree rotation to operate 3-way multi-port diverting valves. Ideal for process piping, powder handling, and bulk material routing.
The 180 degree pneumatic rotary actuator fits applications requiring a full 180-degree rotation. It is widely used in the chemical and pharmaceutical industries.
The 3-position pneumatic rotary actuator supports various standard strokes, including 0°, 45°, 90°, and 180°. It also allows flexible adjustments of position to match exact travel requirements.
This double acting pneumatic rotary actuator includes a handwheel. It provides manual override during emergencies.
The spring-return structure acts as a reliable emergency brake. It automatically returns to the original position when the air supply is cut off.
This heavy-duty rotary scotch yoke actuator powers your valves reliably. It delivers up to 250,000 Nm of torque. It offers strong corrosion resistance for the harshest environments.
Catalog, Data sheets, Torque curves, Drawings, Videos and 3D STEP files available on request.
Hearken rotary pneumatic actuators are built on a fully standardized platform covering 45°, 60°, 90°, 120°, 135°, 180° and 3-position strokes, all in double-acting and spring-return configurations. The shared ISO 5211 mounting face and NAMUR accessory pad let one actuator body fit ball, butterfly, plug and 3-way multi-port valves with no adapter machining. One SKU family, one spare-part list — simpler procurement, faster project delivery, lower inventory cost for distributors.
Hearken rotary actuators and scotch yoke actuators are built for refineries, chemical plants, power stations, and offshore skids. Rack and pinion actuators deliver stable output torque up to 8,000 Nm, and our heavy-duty scotch yoke actuators reach 250,000 Nm peak torque, which is held at mid-stroke so the actuator never stalls when valve friction is highest. An optional three-layer epoxy coating passes 1,000 h ASTM B117 salt spray, with PTFE, ceramic and hard-chrome alternatives for acidic, saline or hygienic service. ATEX Ex II 2GD and SIL 3 capable on request.
1,000,000-cycle durability, zero torque Loss, hearken rotary pneumatic actuator carries with hard-anodized surface treatment (standard 25–50 µm coating) plus a surface-treated piston and rack pinion. POM guide rings and self-lubricating bearings eliminate metal-to-metal contact at the rack pinion interface, so torque output stays at rated value even after 1,000,000 full stroke cycles, which was verified on our testing bench. Optional for supplying the repair kits for extending the lifetime.
Hearken sources the accessories from long-cooperated suppliers. Solenoid valves (3/2, 5/2, 5/3, etc), limit switch boxes with mechanical or inductive switches, pneumatic and electro-pneumatic positioners, and manual override gearboxes are all factory matched to our NAMUR VDI/VDE 3845 accessory pad and ISO 5211 drive interface. Pre-assembled, tested, and shipped as one package, which avoids the wrong assembly problems, wrong size or function selection, reduces the deadline, and avoids the warranty headaches when parts come from different brands or suppliers.
Hearken actuators follow a controlled flow: Aluminum die-casting → CNC machining of body, pistons, and pinion in one fixturing → hard anodizing of the cylinder bore → assembly of seals, springs, and accessories → 100 % air leakage test → 100 % no-load travel and direction test → 100 % rated torque verification on the calibrated test bench. Every actuator leaves the production line with one unique serial tracking number, full material and test traceability, and a signed factory testing report will be provided to our clients.
All actuator body, piston, rack, and pinion surfaces are machined on CNC, holding rack-to-pinion backlash below 0.1 mm and bore-to-piston clearance within ±0.05 mm. Repeatable geometry means every replacement actuator on the same valve line behaves identically during commissioning and re-qualification. Standard ISO 5211 interfaces (F03 / F04 / F05 / F07 / F10 / F12 / F14 / F16 etc…) which are directly mounted on your valves without adapter.
Choose the surface treatment that matches the media, environment, and cycle frequency of your application. Standard hard anodizing for general industrial use, PTFE coating usually for food, pharma and CIP, ceramic coating for high-temperature and abrasive slurry service, nickel and epoxy-polyester coatings for offshore, chemical and marine duties. For more information, welcome to contact the Hearken experienced engineering team.
Hearken actuator 100 % is bubble leak tested, not just a sample, and run through full 0°–90°–0° cycles on the torque test bench to verify start torque, air stroke start torque, and end of stroke torque against published curves. Random units are pulled for accelerated cycle tests up to 100,000 operations. Each shipment ships with a testing report sheet which indicates your order number, the testing report signed by our QC engineers, and the date.
Hearken rotary pneumatic actuators prioritize rapid cycle times while integrating seamlessly with remote control architecture. Built with high-strength, lightweight materials, these automated assemblies maximize operating efficiency while safeguarding site personnel through precise remote actuation.
| Type | Pneumatic Rotary Actuator |
| Rotation Angle | Standard adjustable 90°士% |
| Control Pressure | 2–8 bar |
| Operating Medium | Filtered compressed air |
| Mounting Interface | ISO 5211, NAMUR |
| Piston | Die casted aluminium dual piston |
| Torque Output | 14 Nm up to 8,000 Nm |
| Material | Aluminum Alloy, Stainless Steel, PVC |
| Operating Temperature | -20℃ – 80℃ |
| Low Temperature | -50℃~ +80℃ |
| High Temperature | -15℃~ +150℃ |
| Accessories | Solenoid Valve, Limit Switch boxes, Electro-pneumatic Positioner, Declutchable Manual Override Gearbox, High Visibility Indicator |
| Field | Value |
| Housing (End Caps) | Die-cast aluminum with polyester coating standard; ASTM 304 / 316 / 316L stainless steel (HPAS Series) or corrosion-resistant plastic (HPAP Series) optional. |
| Body | Extruded aluminum alloy, hard-anodized internal/external bore; ASTM 304 / 316 / 316L stainless steel (HPAS Series) or corrosion-resistant plastic (HPAP Series) optional. |
| Pistons | Die-cast aluminum dual piston with anodized/hard-anodized wear surface; stainless steel optional. |
| Pinion / Output Shaft | High-tensile alloy steel, electroless nickel-plated or chrome-coated; SS304 / SS316 stainless steel optional. |
| Drive Insert / Adapter | One-piece Carbon steel / Stainless steel (Square or Star adapter). |
| Springs | High-tensile pre-loaded alloy spring steel with anti-corrosion coating. |
| O-rings / Seals | NBR (Nitrile) standard (-20°C to +80°C); FKM (Viton) for high-temp (-15°C to +150°C), EPDM or HNBR for low-temp (-50°C to +80°C) on request. |
| Fasteners | Stainless steel 304 standard; Stainless steel 316 on request. |
| Position Indicator | ABS / Nylon PA66 / Glass-filled polyamide, high-visibility yellow/red 3D dome with NAMUR slot. |
| Bearings & Guides | Self-lubricating engineering plastic (POM / Nylon 46 / Fluorocarbon composite / Polypropylene + GF). |
| Certification | Status | Region |
| ISO 9001 : 2015 | Certified | Global |
| CE Marking (PED 2014/68/EU cat. I) | Compliant | EU |
| ATEX 2014/34/EU, Ex II 2GD c IIC T4–T6 | Certified | EU / Hazardous area |
| SIL 2 / SIL 3 (IEC 61508) | Certified / Optional | Global (SIS) |
| EAC TR CU 010/2011 | Certified | EAEU (Russia, BY, KZ, etc.) |
| IP66 / IP67 / IP68 | Standard / on request | Outdoor, Harsh environment |
| EN ISO 12100:2010 | Compliant | EU |
In addition to the standard 90-degree (quarter-turn) configuration, we provide customized 120-degree, 135-degree, and 180-degree rotary stroke actuator for three-way valves or special diverter valves, which also support mechanical limit adjustment.
We recommend the HPAS pneumatic actuator.
Yes, the weight is exactly the same. However, using an oxidized piston makes your rotary pneumatic actuators last much longer.
The hard-anodized surface provides excellent hardness to handle heavy side-loads. At the same time, it cuts down friction to give you better torque output. This protection also stops rust and galling, so the actuator won’t seize up in harsh environments.
The former refers to the torque output when the actuator is in a single-acting, air-to-open configuration, which must overcome the spring’s inherent torque; the latter refers to the torque output by the spring during closure when the air supply is cut off.
For high-frequency applications, we use high-wear-resistant POM plastic guide rings and bearings at the contact surfaces of the piston and rack-and-pinion, effectively preventing direct metal-to-metal friction. This significantly extends the service life of the seals, ensuring the product maintains stable torque output even after millions of cycles.
Yes, you can. Our actuators come with dual stroke adjustment screws for a ±5 tuning range. This feature lets your team easily recalibrate the valve on-site. It quickly fixes minor seat wear to ensure a tight, leak-free shutoff.
Ambient temperature.
Yes. Hearken Flow actuator’s pneumatic passages are fluid-dynamically optimized. When equipped with a high-Cv Quick Exhaust Valve, emergency opening and closing operations can easily be achieved in less than 1 second.
In addition to the standard configuration, we offer optional high-temperature-resistant Viton or low-temperature-resistant silicone O-rings and FKM. This ensures the actuator maintains airtightness and torque output in extreme ambient temperatures ranging from -60°C to +150°C.
Yes, it can withstand high temperatures.
For media such as dust and slurry, PTFE soft seals are highly susceptible to wear. We strongly recommend using metal hard-seal ball valves with our high-frequency actuators; this valve assembly effectively reduces unplanned downtime.
Higher air supply pressure results in greater output torque and faster switching speeds; insufficient pressure leads to weak actuation and slower speeds.
The top NAMUR mounting platform is constructed using one-piece molding or high-strength fasteners, ensuring that it will not loosen or cause signal distortion when mounting heavy-duty solenoid valves or positioners in applications with severe pipeline vibrations.
