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How Bubble Tight Dampers Works?

Dampers are mechanical devices. Dampers are usually introduced into fluid flow systems to regulate the flow or to stop it completely. Dampers are designed so they can perform various functions, like controlling the volume of fluid, determining the direction, or shutting off or isolating in case of situations that need such an action.

Types of Dampers


Under normal circumstances, the operating environment determines the design of the system and the type of damper used. While low leakage control dampers and open or closed HVAC dampers require these devices to provide a function that provides the lowest possible efficiency, in more severe environments, where leakage of the fluids can lead to safety concerns, use of air-tight dampers and bubble tight isolation dampers is made.

These dampers provide complete control over fluid flow, and there is no possibility of leakage. The dampers that provide high efficiency have to be made of corrosion resistant materials that guarantee uninterrupted operation, and in some cases, these dampers must be able to function even when explosions are a possibility.

What Does Bubble Tight Mean?

This is a phrase that is indicative of the sealing ability of any valve or control device. When these valves or dampers are pressure tested with high air pressure, the leakage that gets past the seals provided by its closing devices, plates or discs, is collected and allowed to bubble through the water. A damper that is bublle tight will not show any air bubbles during testing.

EB Air Bubble Tight Dampers (BTD)

Bubble tight isolation dampers are used in building isolation systems for room isolation, in containment housings, dust collectors, and HVAC systems. They can be introduced in both square and round ducts and can be designed to operate in temperatures ranging from -50 to 375 degrees Fahrenheit.

A bubble tight damper is one that has the lowest possible leakage ratio, which has to be zero leakage damper. The blade or disc must be designed for the rated pressure and will have silicone rubber seals that eliminate any fluid leakage around its periphery in the closed position.

The Working of Bubble Tight Dampers

Dampers can operate manually, or through pneumatic or electrical controls. These dampers work on the rotating disc principle, where the disc is controlled through an actuator that is located outside of the fluid flow stream, so it is not distorted in any way during operations.

This requires a jackshaft to penetrate the housing, which requires seals to maintain the integrity of the damper. These seals are positioned so they can be serviced from outside the housing of the damper.

The seal around the blade or disc will firmly sit against the gasket made from silicon or neoprene and covers the frame of the opening that permits fluid flow. This ensures that there is no metal to metal contact between the disc gasket or the frame.


Bubble tight isolation dampers are used as shut off devices in industrial applications, like process applications, wastewater treatment plants, mining ventilation, and laboratories, etc.

EB Air Control Inc. manufactures these HVAC products, which have the design and technology required to ensure the proper handling of projects requiring the highest quality and performance.

They serve pharmaceutical, health care, manufacturing, power plants, water treatment plants, and food industries besides many other buildings. Inquire today for a bubble tight dampers cost estimate.

ebair_wpHow Bubble Tight Dampers Works?

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