What Are Blast Gate Dampers and What do They Do in Extraction Systems?

If you’ve ever dealt with dust extraction or waste ducting, you’ve likely come across the term “blast gate damper.” These little workhorses don’t usually get the spotlight, but they do a lot of the heavy lifting when it comes to airflow control. At a glance, they’re simple mechanical devices, but they impact the performance of your system. That’s where things get interesting.
In this article, we’ll break down how blast gate dampers work, where they fit into your setup, and what makes one type better suited than another. This isn’t a sales pitch, but a practical look at a piece of kit that helps keep extraction systems running smoothly and efficiently.

The Role of a Blast Gate Damper in Extraction Systems

Blast gate dampers, sometimes called gate valves, are found in all sorts of setups, especially where dust or particles need to be moved out of the way. Wood dust, plastic shavings, powder – you name it. These dampers help direct the airflow in ductwork, making sure the suction goes where it’s needed, when it’s needed.
In everyday use, this might mean blocking off parts of the system you’re not using, or opening up a branch to a machine you’ve just switched on. In a setup with multiple machines feeding into a single extraction unit, blast gates help prevent energy waste by keeping airflow focused.
They also support systems that can’t run all machines at once. In that case, dampers help you manage which machines are active and getting airflow at any given time. It’s a simple fix that saves on power and extends the life of your extraction equipment.

Making the Most of Your Airflow

When dampers are fitted properly, they help keep everything running as it should. You’re not just turning airflow on or off – you’re tuning it. That means keeping suction levels right where they need to be, without overloading parts of the system or letting dust settle where it shouldn’t.
Most manual dampers have a sliding blade that moves easily and then locks in place with a thumb screw. Once it’s set, it stays put, so there’s no need for constant adjusting. You can also add these dampers to existing systems – no major overhauls needed.

Manual or Pneumatic? What to Know

At Ducting Express, both manual and pneumatic blast gate dampers are available. Which one you go for depends on your setup and how hands-on you want to be.

Manual Dampers

These are the straightforward options. You slide the blade into the position you want and tighten it with the screw. Easy to use, especially when the damper is within reach. If you’re setting up a small workshop or only adjusting occasionally, manual works just fine.

Pneumatic Dampers

These ones run on compressed air. Instead of turning a screw, a pneumatic ram moves the blade open or closed. They’re either fully open or fully shut – no halfway options like with manual dampers.
Control options include:

• Electric solenoid valves (24V AC, 24V DC, 110V AC, 240V AC)
• Manual pneumatic levers – These can be used to control a single pneumatic damper or to operate two dampers in sequence, depending on your system layout.
• Pneumatic Control Kits – A practical solution for managing airflow in systems with more than one damper. These kits can be configured to open one damper while closing another, or to control multiple dampers from a single point.

Pneumatic (automatic) blast gates dampers are a solid pick when your ducting is out of reach, say, up high, or if you’re automating parts of your system. For example, you can wire them up to open when a machine powers on and close again when it shuts off. No need to touch a thing.

Materials and Build

The body is made from die-cast aluminium, which keeps it lightweight but strong. Inside, the blade is typically Zintec steel. If your system handles more aggressive or corrosive materials, there’s a 316 stainless steel blade option too.
For larger setups, Ducting Express also offers versions built with galvanised steel, giving you a tougher alternative when needed.

Sizing Options

There’s a wide range of sizes to choose from:

• Aluminium-bodied dampers: 63mm, 80mm, 100mm, 125mm, 150mm, 160mm, 180mm, 200mm, 224mm, 250mm, 280mm, 300mm, 315mm, 355mm
• Galvanised steel models: 400mm, 450mm, 500mm, 560mm

Everything’s designed to fit into either a new system or an existing one, so no need to start from scratch if you’re upgrading.

Setting It Up – Accessories That Help

Installing a blast gate damper isn’t complicated, but the right accessories make it even smoother. Ducting Express has:

• Spiral and flex adapters – These short pieces of ducting have pre-cut slots so you can clamp the damper into place. Both ends have male spigots, which slot into spiral ducting or allow flexible ducting to be fitted over them.
• Quick-release clips – For Express Duct systems, these make attachment tool-free and fast.
• Pre-slotted duct sections – Ideal when you’re dropping a damper into an existing line.

With the right fittings, it’s basically plug-and-play.

How to install Blast Gate Dampers

Final Thoughts on Choosing the Right Blast Gate Damper

If you’ve made it this far, you probably already know that blast gate dampers aren’t just a side note in your system. They can save you power, make extraction more efficient, and keep your workspace cleaner with less effort.
Whether you’re adding them to a new setup or tweaking an old one, it’s worth spending a few minutes choosing the right type, size, and control method.
Need help picking the best blast gate damper for your setup? Ducting Express has been around long enough to have seen every type of system, and we’re happy to help. With a range of manual and pneumatic options, and accessories to match, we are one of the largest stockists of blast gate dampers and associated ductwork components.