Dust Collection Hoods
Custom Industrial Duct Hood Design and Fabrication
US Duct offers unrivaled expertise in custom dust collector hood design and fabrication. We are uniquely qualified to combine experience in solving various collection problems with years of metal fabrications experience to assist customers in designing suction hoods.
PROBLEM:
It is very common for a collection system to involve a unique situation, such as a specifically designed machine, an unusual workflow process, a unique dust or material — or a combination of all of these conditions.
SOLUTION:
US Duct personnel will work with you to understand ALL of the dynamics of the application and then fabricate a solution. They can show you a wide variety of past solutions and create a 3D drawing of any proposed solutions. US Duct can fabricate a custom hood for you at a reasonable price.
When You Need a Custom Duct Hood Solution — Example Applications
Custom dust suction hoods are an essential part of virtually every dust collector collection system. The objective is to design a hood that is able to capture the fugitive dust or fume, at a velocity that will pull it away from its normal trajectory, and from a distance that is suitable to the application. These examples highlight the complexity of designing a hood and the futility of just building a ‘box’.
- A hood on a dump bin must be able to capture dust that spews up from the dumping while not being so aggressive as to pull the material that is being dumped.
- A router hood must be able to capture flying wood chip, while not being in the way of the work space.
Designing a Custom Suction Hood — What You Need to Know
The proper design begins with understanding the dust, its characteristics and the velocities at which it can be conveyed. It continues on to the understanding of the work process — is the dust floating, or being propelled by an action? The design must consider other things — what is generating the dust/fume and where is the operator if there is one?
It is also important to understand the dynamics of air. Most people think that suction occurs equally across the face of a hood. For example: given a 4″ x12″ hood (or any size) they would think that the air is coming equally at all points along the 48 square inch face. And they would expect it to dimension equally the further you are from the face. But the air is a liquid and does not function that way.
To help understand this consider a hood as being like the opening of a 5-gallon bucket. As you lower the bucket into a deep pool, you notice that the water is flowing around the edges first. Even if you quickly submerge the bucket, the water comes in from the side. Yes, these dynamics are related to the fact that the bucket is surrounded only on the sides by the water and it is not meant to be a demonstration of all the actual physics, but it is actually a very good picture of what takes place with a hood.
As the vacuum is created by the suction, the air that is going to fill the void will first come in from the sides of the hood. In fact, the strongest point of suction on a straight hood (no flange) is on the outside of the hood and just behind the edge. Prove it to yourself using a cigarette and a hood. The ability of a hood to ‘reach out’ can, therefore, be dramatically increased by adding a right angle flange to the edges of a hood. This prevents the air from ‘lipping’ around the sides.
US Duct assists customers by getting a full understanding of the work process, the generation of the dust, the type of dust, the collector, and the air available. Using experience from previous fabrications, they then can assist in the design and creating a 3D drawing of the proposed solution.
Bell Mouths Can Improve Pick Up
Bell Mouths are an additional component that can be used that will maximize the pick-up point area. They essentially function as a “mini-hood” to improve air-flow dynamics for collection. By extending the mouth of the duct, the surface tension required to create negative pressure (suction) is created across a wider, lower area. The bell mouth’s configuration improves pick up. US Duct’s bell mouths can be added to existing systems and are available in clamp-connect and flange-connect options.
Floor Sweep Hood
US Duct’s Floor Sweeps are used to remove debris from the shop floor where clean up is needed. The double hinged door is held closed by the vacuum of the system and when opened, allows for debris to enter the system. Our floor sweeps come standard with rolled-lip ends that attached easily to our clamp together duct system. Raw, flanged and US Tubing connection ends are also available. Welded floor anchor angles are available as well.
- Rolled-Lip, US Tubing or Flange Ends
- Floor anchor angles optional
- The cover plate has a foot push tab
