How to Measure Dust Collector Filter Bags

Need new filter bags? Learn how to measure them and which dimensions are most critical.

If you're looking to replace your filter bags, your first step is to make sure you get the right measurements. If you have a double beaded snap band filter bag, there are three crucial dimensions you'll need in order for your supplier to get you the right replacements. We're addressing those critical dimensions with this short instructional video below. We're also sharing some tips on how to get them measured right the first time around. By spending a couple of minutes on this video, you can avoid the most common problems people run into when they order the incorrect filter bags.
 

Common Problems To Avoid:

  • Unscheduled shut-down resulting in production loss
  • Clogged filters causing a production delay
  • Spending more time and money to get the correct set of filter bags
 
 

 

Video Transcript:

Hi this is Bob from U.S. Air Filtration.

Today I'd like to show you how to measure a standard double beaded snap band filter bag.

To measure a bag, you need to get three critical dimensions. And I have a short sample bag here to illustrate this.

The first dimensions that we need to know is the snap band size. This is actually the hole size in your baghouse that the bag snaps into.

We also need to know the bag body diameter. Which is the diameter of the bag, at the midsection of the bag.

And we need to know the overall length.

Let's start by measuring the cell plate of the bag. The best way to do this is to actually measure the hole in your baghouse, if you're able to.

I have here a sample of a hole; a cell plate hole in your baghouse. And to measure this you want to take the tape and measure across the hole.

Don't take and stick it like this or you won't get a very accurate reading. Lay the tape across.

Start on a number that you can remember. Like I am measuring on six. And measure to the widest part of the hole.

And you want to the nearest sixteenth of an inch. In this case, this bag has an exactly six inch cell plate hole.

If you are unable to measure the cell plate hole in your baghouse, then the next best thing is to be able to snap your bag into cell plate templates of various sizes to determine the size of your cell plate.

This is a template I have here, which happens to be a six and a quarter inch hole. And I'm going to take this bag and snap it in.

You hear it snap. It's nice and tight. And so this bag fits a six and a quarter cell plate hole.

We have various cell plate sizes here at U.S. Air Filtration. So if you need us to help you determine what size your bag is, we can snap them into these templates and figure it out.

The next measurement we need is the bag body.

And the way we measure this is by laying the bag flat, smoothing it out, and simply measuring across the bag.

So, in this case, this bag measures about nine and three eighths across.

Once we know the bag body we can do some math to figure out what the actual diameter is.

Lastly we need to know the length.

And I Chris who is going to join me here and help measure this.

When we the length of the bag, we want to measure from the very end of the bag on the snap band side to the top seam, or top stitch, on the bottom end of the bag.

This is where the actual disc bottom is, and where the inside dimension of the bag would stop.

Imagine reaching your hand inside the bag and where your fingers would hit the bottom of the disc, that's where we're trying to measure to.

So Chris, if you'll take that and hook it over the top of the bag.

When we measure these bags we want to measure along the seam. And we want to pull it nice and snug so there is no sag. And measure to that top stitch. Again to the nearest sixteenth of an inch.

In this case, this measures thirty nine and five eighths of an inch.

If you'e measuring a felt bag like this one, you'll want to hold it up int he air when you stretch it tight to make sure you're getting it tight.

If this bag was a woven material, the woven material tends to be more stretchy.

And so I recommend putting it on the table or the floor. You still want to pull it tight to take your measurement. That way you'll get a more accurate reading.

With those three measurements; the length, the flat width of the bag, and your cell plate hole we can make the bag to fit your baghouse.

 

Related Resources:

Dust Collector Change Out Check List

Filter Bag Construction

The Best Filter Media for your Application

Guide to Filter Bag Treatments and Finishes