Custom-Engineered Butterfly Dampers for Industrial Airflow Control

Our most economical and best-selling dampers

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Custom-Engineered Butterfly Dampers for Industrial Airflow Control

Kelair designs each butterfly damper to deliver reliable airflow control, isolation, and long-term performance in demanding industrial environments. A butterfly damper uses a single rotating disc mounted on a central shaft within the duct. When the blade is parallel to the airflow, it allows maximum flow. When rotated closed, it seals against the duct wall to restrict or isolate the air stream.

Kelair’s butterfly dampers are custom engineered for each application, with sizes ranging from 6 inches to 144 inches and temperature capabilities up to 2,200°F. These units are widely used across power generation, pollution control, petrochemical processing, and heavy industrial systems where durability and consistent operation are essential.

As Kelair’s most economical damper solution, this design provides cost-effective isolation and modulation without sacrificing performance. Whether used as a standalone damper or alongside related components such as a butterfly valve, each unit is built to order with application-specific materials, seals, and actuation systems. Variations such as a butterfly backdraft damper can also be engineered for one-directional airflow control in specialized systems.

What is a Damper?

Butterfly Damper Specifications: Sizes, Materials, and Performance Ratings

  • Sizes: 6″ to 144″
  • Process Temperature: up to 2200° F
  • Configurations: round, square, & rectangular
  • Construction: S.S. or painted C.S. (others available upon request)
  • Shutoff: up to 99%
  • Seal Options: tad pole, metal seat, swing-thru; control & balancing
  • Actuation: manual, electric, pneumatic (spring return and failsafe available)
  • Modulation: open/closed or modulating
  • Pressure: up to 1-PSI & 4000 FPM process air (higher available upon request)
  • Ball bearings and shaft packing glands standard up to 400°F
What is a Damper?

Actuation Systems: Manual, Pneumatic, and Electric Drive Options

Kelair offers multiple actuation options to ensure each butterfly damper integrates seamlessly into plant control systems and operational requirements.

  • Manual actuators (handwheel or lever) provide simple, dependable positioning for basic control applications
  • Pneumatic actuators are ideal for fast-response isolation, delivering reliable open/close cycling with optional fail-safe configurations
  • Electric actuators enable precise positioning and modulating control, integrating with DCS, PLC, or building automation systems

Actuator selection impacts response time, positioning accuracy, and system integration. Kelair engineers evaluate each application to ensure proper torque, speed, and control compatibility.

Lead times are designed to support project schedules:

  • 2–3 weeks for dampers without actuators
  • 4–6 weeks standard for fully actuated assemblies
  • 3–4 weeks expedited when required

Industries and Applications That Rely on Kelair Butterfly Dampers

Kelair butterfly dampers are used across a wide range of industries where airflow and gas control are critical to system performance.

  • Power Generation: Used for boiler isolation, flue gas bypass, and combustion air control in high-temperature environments
  • Pollution Control Systems: Applied in scrubbers, baghouses, and precipitators to isolate duct sections and manage gas flow during maintenance
  • Petrochemical & Refining: Handle corrosive gases and elevated temperatures in process ventilation systems
  • Cement, Mining, and Bulk Processing: Designed to withstand abrasive particulate and heavy-duty operating conditions

In many of these systems, butterfly dampers work in conjunction with other components such as a backdraft damper or specialized duct fittings to provide complete airflow control and system protection.

Kelair’s engineering experience allows for design considerations such as thermal expansion, particulate buildup, and corrosion resistance to be addressed from the outset, ensuring long-term reliability in harsh environments.

Request a Custom Butterfly Damper Quote from Kelair

To receive an accurate quote, Kelair’s engineering team requires detailed application information, including:

  • Damper type or configuration
  • Duct diameter
  • Operating temperature range
  • Pressure requirements
  • Required shutoff percentage
  • Preferred actuation method

Kelair works directly with engineers and facility operators to review each project and recommend the most effective solution. This direct collaboration reduces delays and ensures specifications are aligned from the start.

Commonly Asked Questions About Butterfly Dampers

What are the benefits of a butterfly damper?

Compact design, most economical, no exterior linkage, higher shutoff rates and they remain consistent along temperature swings.

How are shafts used on these wafer dampers?

The shaft plays a large part in its operation, as it intersects the linkage, bearing, packing, and blade. When inspecting the shaft, make sure to check that it is straight and operating smoothly.

What types of seals are used on a butterfly damper?

The most common types of seals used within these include tadpole seals (which provide better compression; ideal for uneven services) and metal seats.

Do butterfly dampers require any maintenance?

Although Kelair dampers require minimal maintenance, there are aftermarket parts of the butterfly damper that should be kept in stock and checked regularly.

What does proper care look like for the butterfly damper blades?

Depending on the damper's environment, process, and age, blades can warp or bend over time. Proper care involves regularly checking the blade to ensure there is no warping or twisting, or buildup of debris that could prevent the blade from performing correctly.

What is the minimum information I need to get a quote on a damper?

For the most accurate quote please provide the following information:

  • Type or style of damper. For example: butterfly, louver, Tee, diverter, etc.
  • Preferred material, such as stainless steel, carbon steel, other
  • Pressure requirement
  • Temperature the damper will be exposed to
  • Air flow amount
  • Manual, pneumatic or electric actuation/positioner required
  • Amount of shut off needed (usually in %)