Importance Of Proper Pneumatic Tube, Pipe, And Fittings

When it comes to engineered compressed products, the number one cause of less-than-optimal performance is improper supply line sizing.  This can mean one of two things:

  • The hose, pipe, or tubing running to the device is too small in diameter.
  • The hose, pipe or tubing is big enough in diameter, but too long.

The problem with either of these is line loss (follow that link if you want to do the math.)  Put simply, the air wants to move faster than it’s physically permitted to.  Any time fluid flows through a conduit of any sort, friction acts on it via contact with the inside surface of said conduit.

With smaller diameters, a larger percentage of the air flow is affected…no matter what diameter the line is, the air closest to the inner wall is affected by the friction generated.  When diameter increases, the thickness of this affected zone doesn’t increase proportionally, so larger diameters mean less of the air is affected by friction.  It also means there’s a lot more room (by a factor of the square of the radius, times pi…thanks, Archimedes!) for the air to flow through.

Likewise, with longer lengths, there’s more contact, which equals more friction.  Length, however, is often a non-negotiable.  You can’t just up and move a 100HP air compressor from one part of the plant to another.  So, when we’re talking about selecting proper supply lines, we’re going to start with the distance from the compressed air header to our device, and pick the diameter that will give us the flow we need through that length.  In fact, that’s exactly how to use the Recommended Infeed Pipe Size table in EXAIR’s Super Air Knife Installation & Maintenance Guide:

This table comes directly from the Installation & Operation Instructions for the Super Air Knife.

Once we have the correct line size (diameter,) let’s consider the fittings:

  • Tapered pipe threads (NPT or BSPT) are the best.  They offer no restriction in flow, and are readily commercially available.  If you’re using pipe, these are the standard threads for fittings.  If you want to use hose, a local hydraulic/pneumatic shop can usually make hoses with the fittings you need, at the service counter, while you wait.
  • If you need to frequently break and make the connection (e.g., a Chip Vac System that’s used throughout your facility,) quick connects are convenient and inexpensive.  Push-to-connect types are by far the most common, but a word of warning: they’re notoriously restrictive, as the inside diameter of the male end is markedly smaller than the line size.  If you use them, go up a size or two…a quick connect made for 1/2 NPT connections will work just fine for a 1/4″ line:
  • The nice thing about these quick connects is that you don’t have to depressurize the line to make or break the connection.  If you have the ability to depressurize the line, though, claw-type fittings (like the one shown on the right) provide the convenience of a quick connect, without the restriction in flow.

Proper air supply is key to performance of any compressed air product.  If you want to know, at a glance, if you’re supplying it properly, install a pressure gauge right at (or as close as practical) to the inlet.  Any difference in its reading and your header pressure indicates a restriction.  Here’s a video that clearly shows how this all works:

I want to make sure you get the most out of your compressed air system.  If you want that to, give me a call with any questions you might have.

Russ Bowman
Application Engineer
EXAIR Corporation
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Swivel This Or Swivel That

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The Nano Super Air Nozzle is available with an M6 x 0.75 thread OR a 1/8 NPT thread.

I recently took a call from a customer who was looking for a Nano Super Air Nozzle with a swivel and NPT threads.  We have two versions of this (see above) thanks to our plethora of options.  We offer a newer Mini Swivel Fitting that will allow the M6 thread of the Nano Super Air Nozzle to go straight into the swivel joint and it gives you a 1/8″ MNPT on the opposite side.  This still permits the 25° from center range of motion as the standard swivels do but, with a smaller footprint,  is able to get into tighter spaces.

1110SSW - Nano Super Air Nozzle w/ Mini Swivel Fitting
1110SSW – Nano Super Air Nozzle w/ Mini Swivel Fitting

 

The other option is to utilize a model 1110SS-NPT which is a Nano Super Air Nozzle w/ 1/8″ NPT adapter, then add a 1/8″ NPT Swivel fitting which is a model 9052.  This option is a little bulkier, but if you needed some extra length on the nozzle side to get closer to the target area then it would be helpful.   This unit also offers the 25° from center range of motion and still gives a 1/8″ MNPT thread to plug into your system.

1110SS-NPTW - Nano Super Air Nozzle w/ NPT Adapter and 1/8" NPT Swivel Fitting
1110SS-NPTW – Nano Super Air Nozzle w/ NPT Adapter and 1/8″ NPT Swivel Fitting

As you can see in the picture above, the Mini Swivel fitting with Nano Super Air Nozzle is a more compact option, but does not reach as far as the standard 1/8″ swivel with NPT Nano Super Air Nozzle.  No matter the case, we have them both in stock and ready to ship same day on orders received by 3 PM EST that are shipping within the states.

Chances are if you have a need for a compressed air blow off, we will have more than one way to get the job done.   Our goal is to sell you the best engineered solution that will get the job done and make your life easier.  If you would like to discuss any of your applications, please contact us.

Brian Farno
Application Engineer
BrianFarno@EXAIR.com
@EXAIR_BF

Is Your Compressed Air Blowoff As Flexible As Your Production Line?

                On numerous occasions I have encountered applications where a customer runs several different parts or products through the same line or process and they need to be blown off before entering a certain stage.   This will sometimes not be achieved efficiently with using just a manifold or a system that is designed to blow off one part.  Sometimes it can work through just turning up and wasting compressed air just to blowoff that different part that the line was not originally designed for.    

                Rather than crank up your compressed air or have to make a new mount/ manifold every time there is a line change, install some of our Stay Set Hoses and or Swivel fittings

 

                The Stay Set Hoses can be bent and formed to reach almost any angle of a part that is coming through your blowoff stage.   The Stay Set Hoses are available in ¼” MNPT fittings, 1/8” MNPT fittings, or a combination of both, along with a variety of lengths.  You can mount anything from a Nano Super Air Nozzle all the way up to a Super Air Amplifier or even a Super Air Knife.   These would make adjusting your blowoff process much simpler when doing a line change. All you have to do is grab the hose with your hands and reposition to the correct location for the new product run.  If you don’t need that much adaptability, say you just need to refocus the nozzles every once in a while for a size change, check out our Swivel Fittings.  The application below is used on a line where the product sizes and features change frequently.

                The Swivel Fittings are offered in a variety of sizes and allow movement of 25 degrees.  They are also constructed of 303 Stainless Steel.  

                All in all, if you struggle with line changes and your rigid mount blowoff process playing nice together, it may be time to consider our Stay Set Hoses and/or Swivel Fittings.  

 Have a good 4th of July to all of our followers in the US, and a great weekend to to everyone. 

Brian Farno

Application Engineer

BrianFarno@EXAIR.com