1. Product Overview
An electric ventilation butterfly valve is an automatically controlled valve that integrates an electric actuator with a butterfly valve body. It is widely used in HVAC systems, industrial ventilation, flue-gas desulfurization, dust collection, and large duct or flue systems to regulate airflow and to open or shut off the medium. The product shown here is a typical example: nominal diameter DN800, flanged connection, a black cast-iron or welded-steel body, and a smart electric actuator with an LCD display on top, equipped with a handwheel, local electric operation and terminals, allowing switching among manual, local electric and remote automatic control modes.
2. Structure and Components
(1) Electric actuator: including the drive motor, handwheel, LCD display, control-mode selector, terminals and local electric operation unit. The handwheel is connected to the motor drive train through a clutch mechanism for bumpless switching between electric and manual operation; the LCD shows valve position, fault and status; the terminals connect power and control/feedback signals such as 4–20 mA or 0–10 V.
(2) Valve body assembly: including the shell, thrust unit, damper (disc) and flanged connection. The disc is circular and linked to the thrust unit through a shaft; the thrust unit transmits the actuator torque to the disc, rotating it between 0° and 90°.
3. Working Principle
The working principle is straightforward: after the actuator receives a control signal (on/off or analogue), the motor drives the thrust unit through a reduction gear train, rotating the valve stem and disc. When fully open, the disc is parallel to the flow path, causing minimal resistance; when rotated 90° to the fully closed position, it sits perpendicular to the flow path for tight shut-off. Any intermediate angle enables continuous flow regulation. The valve is normally fitted with limit switches and torque switches that cut off motor power at the end of travel or under overload, protecting both the valve and the actuator. In the event of a power failure or during maintenance, the operator can trip the clutch handle to switch the actuator to manual mode and operate it directly by turning the handwheel. This hand/auto switching mechanism, composed of a handle, clutch and compression spring, guarantees safe handwheel operation under any condition.
4. Key Features
1.Simple structure, small size and light weight, with low installation-space requirements.
2.Fast opening/closing with low operating torque; full travel usually takes only tens of seconds.
3.Low flow resistance and high flow capacity, especially advantageous for large sizes such as DN800.
4.Available in both on/off and modulating (continuous proportional) modes, with a turndown ratio up to 30:1.
5.Supports electric/manual switching so the valve can still be operated by hand during power outages or maintenance.
6.Can be equipped with LCD display, remote signals and bus control (e.g., Modbus) for centralized monitoring.
7.Optional overheating protection, torque protection, explosion-proof and insulation configurations suit different service conditions.
5. Key Technical Parameters
| Parameter | Typical value |
| Nominal diameter (DN) | DN50–DN3000+ |
| Nominal pressure (PN) | PN10 / PN16 / PN25 |
| Media | Air, flue gas, dust-laden gas, etc. |
| Power supply | Three-phase 380 VAC / Single-phase 220 VAC, etc. |
| Control signal | On/Off type / 4–20mA, 0–10V modulating type |
| Protection (IP) | IP65 / IP67 |
| Body material | Cast iron, carbon steel, stainless steel, etc. |
Per GB/T 12238-2008 (Elastic-seated butterfly valves for flanged and wafer connection), butterfly valves may be driven manually, electrically, hydraulically or pneumatically, and the operating force on a handwheel or handle must not exceed 350 N.
6. Selection Guide
1.Media and temperature: select body and sealing materials based on the medium (clean air / dust-laden flue gas / corrosive gas) and maximum operating temperature.
2.Size and pressure: determine DN and PN from pipeline flow and system pressure.
3.Actuator torque: size the actuator with a safety factor of 1.3–1.5 times the required operating torque.
4.Control mode: choose on/off or modulating type according to the process, and specify the input signal.
5.Functional requirements: decide whether a handwheel, LCD display, limit/torque switches, explosion-proof construction or bus communication is needed.
6.Environmental conditions: select an appropriate IP rating and corrosion protection for outdoor or humid locations.
7. Applications
Electric ventilation butterfly valves are widely used in ventilation, dust-collection and gas-pipeline systems across the power industry (boiler induced-draft and desulfurization/denitrification systems), iron and steel, cement, petrochemical, mining, wastewater treatment and building HVAC sectors. In large ducts and flues they often serve as "dampers" for air-balancing, pressure regulation and isolation during maintenance.
8. Applicable Standards
1.Design & manufacture: GB/T 12238 (Elastic-seated butterfly valves for flanged and wafer connection);
2.Face-to-face dimensions: GB/T 12221;
3.Flange connections: GB/T 9113, etc.;
4.Actuator mounting interface: ISO 5211 (part-turn actuator mounting dimensions);
5.Internationally, API 609 and EN 593 are also commonly referenced.
9. Installation and Maintenance
During installation, pay attention to the flow direction and disc-opening orientation, avoid interference between the disc and adjacent piping or fittings, and support large valves with brackets to bear the body weight. Routine maintenance includes: periodically checking actuator sealing and lubrication, testing the operation of limit and torque switches, verifying consistency between local and remote position indications, and tightening terminal and grounding connections. For long-term storage, keep the handwheel mechanism in the electric position and protect the unit against moisture.
10. Industry Trends and Market
The global electric butterfly valve market continues to grow steadily. According to industry research, the worldwide electric butterfly valve market was valued at approximately USD 1,845.5 million in 2025 and is forecast to reach about USD 2,802.6 million by 2032, a CAGR of roughly 6.14%; the electrically actuated butterfly valve market stood at about USD 4.28 billion in 2025 and is expected to reach USD 7.8 billion by 2034 (CAGR ≈ 6.8%), with water and wastewater treatment the largest application segment (≈32.4%) and Asia Pacific contributing ≈38.6% of revenue.PW ConsultingDataintelo In China, the electric actuator butterfly valve market reached roughly RMB 12 billion in 2025, up 12.8% year on year.
In terms of technology, products are moving toward intelligence and digitalization: LCD human-machine interfaces, bus communication (Modbus/Profibus), IoT remote monitoring, self-diagnostics and energy-efficiency optimization are becoming standard. Under the carbon-peak and carbon-neutrality goals, demand for energy-saving valve replacement continues to grow, and the electric ventilation butterfly valve-as a core component of airflow regulation-faces strong demand in green factories and smart buildings. Fast operation, high reliability, modularity and standardization will be the main directions for selection and design in the years ahead.
