Electric Ventilation Butterfly Valve

Liangfa’s Electric Ventilation Butterfly Valve is designed for motorized airflow control in ventilation ducts, exhaust systems, dust collection lines, and industrial flue gas applications. We offer on/off and modulating actuator options, along with different body materials and sealing configurations to suit specific operating conditions. 

Product Specifications

Select the Right Control Mode

The actuator determines how the Electric Ventilation Butterfly Valve responds to operator commands and automation signals. Before choosing a model, consider whether your system needs simple isolation or continuous airflow adjustment.

On/Off Control

An on/off actuator moves the disc between the specified open and closed positions. This arrangement is suitable for exhaust branches, ventilation ducts, dust collection systems, and other applications where the valve mainly opens or closes an airflow path.

Modulating Control

For systems that need changing airflow, a compatible modulating actuator can receive a 4–20 mA or 0–10 V command. With the correct controller and feedback configuration, the valve can be integrated into a PLC or building management system to adjust its opening position.

Actual airflow does not necessarily change in direct proportion to the valve opening angle. Duct resistance, fan performance, pressure differences, and system layout also affect airflow. Where accurate flow control is required, the valve should be selected and commissioned as part of the complete ventilation system.

Explosion-Proof Configuration

Where flammable gas or combustible dust may create a hazardous atmosphere, the actuator and electrical accessories must be suitable for the site's classified zone. We recommend confirming the hazard classification, required protection marking, temperature class, and applicable certification before specifying an explosion-proof unit. A standard IP-rated actuator is not a substitute for certified explosion protection.

Choose Materials for the Gas Stream

The gas composition, temperature, dust loading, and required leakage performance all influence material selection. We recommend evaluating the valve body, disc, stem, seat, bearings, and actuator arrangement together.

Temperature limits must be confirmed for the complete valve assembly, not inferred from the body material alone. The seat, shaft seals, bearings, actuator insulation, and distance between the actuator and hot duct can all limit the permitted operating temperature.

Reduce Problems in Dusty and Hot Ducts

Ventilation valves often operate in conditions that differ from clean water service. Dust accumulation, thermal expansion, vibration, and uneven duct loading can increase operating torque or affect shut-off performance.

Dust and Sticky Deposits

Fine dust, oil mist, tar, or sticky exhaust deposits may collect around the disc and shaft. Where low leakage is not essential, an unsealed metal design may be worth considering. For applications requiring tighter shut-off, confirm that the selected seat can withstand the particles, chemical exposure, and cleaning process.

Large-Diameter Ducts

Larger discs create greater mechanical loads and may require external shaft bearings, reinforced supports, and a higher-torque actuator. The source information identifies external bearings for larger sizes, but the actual diameter threshold and construction should be confirmed for the selected model.

High-Temperature Flue Gas

When the gas temperature is elevated, the actuator should be protected from excessive heat radiation and conduction. Depending on the layout, an extended mounting bracket or thermal isolation arrangement may be needed. Confirm the permitted temperature at the actuator mounting point as well as at the valve body.

Corrosive Exhaust

Acidic vapours, chlorides, and mixed chemical exhaust can affect both metal parts and seals. Provide the gas composition, concentration, normal and peak temperature, and any condensation conditions before selecting stainless steel or a polymer seat. Stainless steel alone does not guarantee compatibility with every corrosive gas.

Plan the Installation

Correct mechanical installation and electrical commissioning help reduce actuator faults and prevent the disc from binding against the duct or valve body.

Before Mounting

• Confirm the valve's connection type, dimensions, pressure rating, material, actuator voltage, and control mode against the approved order documents.
• Check that the duct flanges or mounting interfaces are aligned and sufficiently supported.
• Remove welding slag, loose rust, and foreign objects from the duct near the valve.
• Inspect the disc, shaft, actuator mounting hardware, cable entries, and any specified seals.
• Reserve enough clearance for the actuator, manual override, wiring, and future maintenance.

Mechanical Installation

• Follow the manufacturer's installation instructions for the specific wafer or flanged design. Do not use installation procedures intended for a different connection type.
• Verify that the disc can complete its required travel without hitting the duct wall, gasket, or adjacent equipment.
• Tighten fasteners evenly and avoid loading the valve body with unsupported duct weight.
• For large or heavy duct sections, provide independent structural support as required by the system design.
• For hot gas service, check actuator clearance and any required thermal isolation before commissioning.

Electrical Commissioning

• Use the rated supply voltage shown on the actuator nameplate and follow the supplied wiring diagram.
• Verify protective earthing, terminal tightness, cable protection, and the required environmental sealing.
• Test opening and closing direction before connecting the actuator to automatic control.
• Set the travel limits according to the actuator manufacturer's procedure to prevent over-travel.
• For modulating models, check command signals, position feedback, and response to the controller before putting the system into service.
• For hazardous areas, installation and commissioning must follow the applicable electrical safety requirements and the actuator's certification conditions.

Do not force the motor to drive a jammed disc. Isolate the power, follow the manufacturer's safe maintenance procedure, and identify the cause before restarting the actuator.

Maintain Reliable Actuator Operation

Maintenance frequency depends on operating cycles, dust concentration, gas temperature, vibration, and environmental exposure. We recommend using the following checks as a starting point and adjusting them to the actual service conditions.

Before inspection or repair, isolate the power supply and make sure the duct is in a safe condition. Hot gases, hazardous process residues, unexpected actuator movement, and stored mechanical energy must be addressed before maintenance begins.

Applications Across Ventilation Systems

Dust Collection and Workshop Exhaust

Used to isolate or control branches in dust collection systems and workshop exhaust networks. For abrasive or deposit-forming dust, assess the disc design, bearing arrangement, and acceptable leakage level.

Boiler and Kiln Air Systems

Motorized valves can control air paths in compatible boiler auxiliary systems, kiln hot-air ducts, and industrial furnaces. High-temperature applications require confirmation of material ratings, shaft support, and actuator thermal protection.

Industrial Flue Gas and Waste Gas Treatment

For exhaust treatment lines, material selection should reflect the gas chemistry, temperature, condensation risk, and required shut-off performance. Corrosive service may require stainless steel or another specified alloy and a compatible sealing arrangement.

HVAC and Building Ventilation

On/off actuators can isolate ventilation branches, while compatible modulating actuators can support airflow adjustment in automated systems. Final control performance depends on actuator sizing, the control system, and duct network design.

Metallurgy and Building Materials Processing

Large air ducts in industrial production facilities may need reinforced shaft support and higher actuator torque, particularly where dust deposits or elevated temperatures increase resistance to disc movement.

Ordering and Project Support

To quote the correct configuration, we need more than the valve diameter. Please share the operating details below so our team can review the actuator, materials, and connection requirements together.

• Required nominal diameter and duct dimensions.
• Connection type, flange standard, and installation drawing where available.
• Gas composition, dust characteristics, and whether condensation is expected.
• Normal and maximum operating temperature and pressure.
• Required leakage performance and whether a soft seat is needed.
• Actuator mode: on/off or modulating.
• Power supply, control signal, feedback requirements, and control-system interface.
• Indoor or outdoor installation, ambient conditions, and any hazardous-area classification.
• Quantity, destination, inspection requirements, and target delivery schedule.

At Liangfa, we provide model-selection assistance, technical parameter confirmation, available drawings, quotation support, and coordination of factory inspection and export documentation according to the order requirements. Our High-Tech Enterprise Certificate can be provided as part of company qualification information. Specific inspection reports, material certificates, and actuator documentation should be confirmed for each order.

We also provide after-sales technical consultation and support for maintenance planning and replacement parts where available. The stated warranty period is 12 months from shipment; applicable terms and exclusions should be confirmed in the sales agreement.

Frequently Asked Questions

Can the actuator connect directly to our PLC?

A compatible modulating actuator can accept specified 4–20 mA or 0–10 V signals, and some configurations provide position feedback. Direct integration depends on the actuator model, control wiring, input/output requirements, and PLC configuration. Please send your control diagram or signal specification for confirmation.

What happens if the power supply fails?

The supplied information lists a manual clutch or handwheel for selected configurations. Manual operation is not necessarily available or suitable on every actuator, so confirm the exact override arrangement and follow the manufacturer's isolation procedure before operating it manually.

Can this Electric Ventilation Butterfly Valve provide a tight shut-off in a dusty exhaust duct?

That depends on the valve design and the required leakage limit. An unsealed metal design may allow some air leakage, while a soft-seated configuration can provide tighter closure when its seal is compatible with the dust, temperature, and gas chemistry. Share the required leakage criterion so we can review the appropriate option.

How should we choose the actuator for a large duct?

Actuator sizing should account for disc diameter, differential pressure, shaft and bearing friction, dust deposits, temperature, and the required operating frequency. Large valves may need external bearings and a higher torque rating. We recommend confirming the actual operating conditions rather than selecting the actuator by diameter alone.

Is an IP65 actuator suitable for an explosive atmosphere?

No. IP65 describes protection against dust ingress and water jets; it does not by itself certify explosion protection. For a hazardous area, the actuator and associated electrical components must have suitable certification for the site's classification and operating conditions.

What should we confirm before specifying high-temperature service?

Provide the normal and peak gas temperature, gas composition, duct pressure, dust loading, required leakage performance, and ambient temperature around the actuator. We can then review the body material, disc and shaft arrangement, seat design, bearings, and any thermal isolation needed for the proposed configuration.