The Neles N1 heavy-duty scotch-yoke pneumatic actuator is a quarter-turn actuator designed for on-off and modulating control. It features a ductile iron center body with carbon steel welded modules, delivers torque of up to 700000 Nm, provides a maximum Safety Integrity Level of SIL 3, and complies with ATEX explosion protection requirements. It can operate with air, natural gas, or nitrogen as the power medium and is commonly used for on-off valve automation in natural gas pipelines, control of process valves in demanding industrial applications, and interlock protection for emergency shutdown valves.
Neles heavy-duty scotch-yoke actuator, N1 Series
Neles
Neles N1 Heavy-Duty Scotch-Yoke Pneumatic Actuator
Pneumatic quarter-turn actuator for valve on-off and modulating control, supporting natural gas supply
- Category
- Actuators
- Power Medium
- Air, natural gas (sweet gas), nitrogen
- Torque Range
- 25 Nm - 218765 Nm @ 4 bar; up to 700000 Nm
Specifications
- Actuator Type
- Pneumatic scotch-yoke quarter-turn actuator
- Control Mode
- On-off control, modulating control
- Power Medium
- Air, natural gas (sweet gas), nitrogen
- Torque Range
- 25 Nm - 218765 Nm @ 4 bar; up to 700000 Nm
- Operating Temperature Range
- -20 to +80 °C (standard); -20 to +125 °C (high-temperature)
- Ingress Protection Rating
- IP66M/IP67M (IEC 60529)
- Explosion Protection Rating
- Ex 2G IIC T6 / Ex 2D IIC T80C (ATEX)
- Mounting Standards
- ISO 5211, VDI/VDE 3845
- Body Materials
- Ductile iron center body, carbon steel welded power module and spring module
- Safety Integrity Level
- Compliant with IEC 61508, up to SIL 3
Application scenarios
Quarter-Turn On-Off Valve Automation for Natural Gas Pipelines
For automating quarter-turn on-off valves in natural gas pipelines, with natural gas available as the supply medium.
Emergency Shut-Off Valve Interlock Protection
For emergency shut-off and safety interlocking of quarter-turn valves in process facilities, providing protective action under abnormal conditions through on-off control.
Process Valve Automation in Demanding Industrial Environments
For on-off or modulating control of quarter-turn process valves in demanding industrial environments. The actuator uses a heavy-duty structure and internal tie-rod mechanism and provides corrosion protection.
Selection points
Heavy-Duty, High-Torque Coverage
At a 4 bar air supply pressure, the N1 series provides a torque range of 25 Nm to 218765 Nm, with maximum torque of up to 700000 Nm, making it suitable for heavy-duty quarter-turn valve actuation.
Internal Tie-Rod Mechanism and Piston-Rod Alignment Design
The N1 series uses an internal tie-rod mechanism and structural features that improve piston-rod alignment, supporting smooth operation for both modulating and on-off control.
IEC 61508 Functional Safety and SIL 3 Capability
The N1 series complies with IEC 61508 and provides a maximum Safety Integrity Level of SIL 3, making it suitable for industrial actuator applications requiring functional safety assessment.
Installation notes
Match the Power Medium to the Operating Temperature
Before installation and operation, confirm that the power medium is air, sweet gas, or nitrogen as specified for the product, and verify the operating temperature range for the specific configuration. The standard configuration is -20 to +80 °C, while the high-temperature configuration is -20 to +125 °C.
Verify the Valve Interface and Actuator Configuration
The N1 Series is designed for quarter-turn valves. Before installation, verify the actuator-to-valve mounting interface and shaft connection in accordance with ISO 5211, and confirm that the selected configuration meets the requirements of the valve installed on site.
FAQ
What valve control tasks are Neles N1 Series actuators suitable for?
The Neles N1 Series is a pneumatic scotch-yoke quarter-turn actuator suitable for on-off control, modulating control, and control valve applications. Its application range includes general-duty, protective, and safety-related services, such as emergency shutdown (ESD), high-integrity pressure protection systems (HIPPS), and compressor anti-surge control.
How are the torque range and power medium for N1 Series actuators determined?
At a 4 bar supply pressure, the N1 Series provides a torque range of 25 Nm to 218765 Nm, with maximum torque of up to 700000 Nm. Air, sweet natural gas, or nitrogen can be used as the power medium. Final selection must be based on the valve breakaway and running torque, supply pressure, operating mode, and application conditions.
How does the Neles N1 Series support SIL safety instrumented system applications?
The N1 Series is suitable for safety instrumented systems compliant with IEC 61508 and rated up to SIL 3. It can be used in safety-related valve control applications such as ESD and HIPPS. The specific safety loop configuration must be verified according to the actual model and application conditions.
What structural and protection features does the N1 Series offer for demanding environments?
The series features a heavy-duty construction consisting of a ductile iron center body, carbon steel welded power module, and spring module, together with an internal tie-rod mechanism. The actuator incorporates ball bearings, flexible couplings, and hardened yoke thrust pin bearings to support piston rod alignment and smooth operation. The springs are lubricated for their full service life and treated with an epoxy coating. The exhaust valve includes an integral check function, the protection rating can reach IP66M/IP67M, and a second exhaust valve is provided to detect leakage in the cylinder piston rod sealing area.
What are the mounting interface and applicable temperature range of N1 Series actuators?
The N1 Series mounting face complies with ISO 5211 and VDI/VDE 3845 and can be paired with compatible quarter-turn valves and accessories. The standard temperature range is -20 to +80 °C, while the high-temperature configuration covers -20 to +125 °C. The actual configuration must be verified according to the valve, environmental conditions, and process requirements.