In Heating, Ventilation and Air Conditioning (HVAC) systems, the final control process for the airflow in the system is a damper that operates in conjunction with the blast gate.

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Blast gates have many uses in marine, agricultural, furnace and grain drying applications. They are used in these industries to enable the exhaust system to remove dust, smoke, and particles. Air dampers are part of the same air handling process in which the airflow through fans is controlled to improve the power and effectiveness of the fan.

Effectively, the ductwork blast gate damper operates as a valve, shutting off part of a dust extraction system operated by vacuum. A sliding plate is used to block the vacuum line. However, for many applications, a custom-designed damper is the best choice because HVAC systems vary so much in their configuration and in the type of extraction that is required.

Blast gate dampers in vacuum ducting

Blast gate dampers are often used in a vacuum ducting system to shut off lines that are not being used because this ramps up the amount of vacuum power available to machines that are in use. Blast gates can be automatically or manually operated. In larger systems, the blast gate can also be operated remotely, and a spring-loaded solenoid may be used to operate the gate.
In addition to airflow, many industrial users require dampers that can regulate temperature or pressure depending on the process being regulated. In fact, dampers are frequently customised according to specific industrial requirements. For example, there may be a need to control the levels of leakage and pressure drop. In this case, slide gate isolation dampers may be used in combination with actuators.

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Sliding dampers

Sliding dampers are usually used to control airflow in duct systems by shutting off a line. They come in two versions: electro-pneumatic or electrical. It is essential that users are protected from the moving parts, so many of the dampers come with a cover to prevent injury.

This is a fairly complex area, so it may be helpful to discuss the specific installation with an expert ductwork supplier like, who can advise on the best configuration and parts to buy.

A helpful supplier will also be able to advise on custom solutions to your particular requirements.