Compressed Air Is Cool

Recently, I had the pleasure of assisting an engineer whose company makes honing tools.  One particular item is a large, heat treated, alloy steel part.  When it comes out of the furnace, it’s over 1,700°F.  Needless to say, it has to cool off quite a bit before they can do anything with it.  He was doing the best he could with some large shop fans when he called me to pursue the possibility of doing it quicker with engineered compressed air products.  His goal was to cool the part to 600°F in fifteen minutes.

For those of you without an engineering background (or for you engineers who “phoned it in” during Heat Transfer and Fluid Flow), there are 2 components to convective heat transfer: temperature differential, and flow of the cooling medium.  Increase either or both of these, and you get better results.

In this particular case, the temperature differential between the part (1,700°F) and ambient (80°F) is already huge.  Now, a Vortex Tube device could cool the air an additional 50° or so, but that wouldn’t really have much overall effect.  That left us looking at increasing the air flow.

We considered several options, but the Super Air Knife’s 40:1 amplification ratio made it the obvious choice for maximizing flow, while minimizing consumption.   I didn’t do the CAD drawings (although CAD is my favorite video game), but I supplied my customer with the 3D models he needed to design his system.  He incorporated three 12” Super Air Knives, supplied with plumbing kits.  He mounted them with our Universal Air Knife Mounting Systems.  It made for a very nice looking little rig.

Based on the initial data, my heat transfer calculations were in the “close but no cigar” range – making some conservative assumptions, I figured it could take as long as half an hour to reach 600°F.  When all was said & done, though, the cooling performance was a great improvement over the fans, and even better than my calculations indicated it would be – the system actually cooled the part to 200°F in twenty minutes.  Which was curious, because I actually paid attention in, did well in, and, dare I add, even enjoyed HT/FF.

As I come to grips with my failure to know everything, I’m encouraged that the as-yet unknown variables were skewed in our favor.  Yeah; compressed air is cool.  Even cooler than I thought.

Russ Bowman
Application Engineer
EXAIR Corporation
(513)671-3322 local
(800)923-9247 toll free
(513)671-3363 fax

Knowledge [Base] is Power

I have recently placed a post on our Facebook page about our Knowledge Base and I am asking for comments about it. Please take some time to look into the Knowledge Base and its valuable information. After looking at it leave us a comment on Facebook (you will need to LIKE our page) or this blog. Let us know if you would like to see something which is not there, or if you have a question about the information, what would you add?

Right now You will see Air Data; a collection of pressure, force, flow and heat conversions. It also explains how to calculate air consumption at different inlet pressures which is helpful when you only have air data at 80 PSIG but your line pressure is 60 PSIG. Air Data also explains the best practices for air system piping and charts pressure loss through lengths of pipe.

You will see our calculators to determine potential air savings of switching to EXAIR products. You can link to this blog or read our FAQ’s. You can learn about our Efficiency Lab Service, view our product videos, and browse our wiki. There is also a link to our Twitter feeds.

If you choose to register you can gain these valuable resources: An Application Database with over 800 examples of how our products have solved a problem. Our CAD library offers 3D models and 2D drawings for download , all of our products are represented in multiple formats. You can also download the entire catalog or individual sections in .pdf form, we even have a section optimized for use with the iPad. And you can also view or present our slide shows to learn or teach about the products.

So help us gain knowledge, what did you see that we are missing? What do you think we should add or do differently? Leave a comment at our Facebook page (don’t forget to LIKE it) or on this blog.

Thank you,
Kirk Edwards
Application Engineer

Optimize Compressed Air: Part 6 of 6.

If you didn’t read yesterdays blog you should really take a minute to visit it. It is even more proof that EXAIR is always on the leading edge in our industry. It also speaks about our goal to help you optimize your compressed air system. This is all done through our Six Steps To Optimizing Your Compressed Air System. For those that have followed my blog mini series you will know that this is the final part in our journey to optimization. This blog will give you the last piece of the puzzle.

The final digit in the combination to unlocking compressed air optimization is…

Control the air pressure at the point of use to minimize air consumption.

This is done by simply installing one of our pressure regulators. They are available in multiple pipe sizes and flow capacities. The simple reduction from operating at 100 PSIG to 80 PSIG will reduce your energy use by almost 20%. Not to mention that some of your operations may be able to be reduced even lower which equates to even more savings.

For those that don’t know the movie Young Guns like I do, the group of deputized marshals were also known as the Regulators.  The trailer for Young Guns is below, just for fun.

Not only are all of our pressure regulators standard stock items for us (this means they can ship same day if ordered by 3:00 P.M. Eastern Time), we also have 2D and 3D CAD drawings available through our CAD Library. This allows you to completely layout your compressed air system without ever cutting a pipe.

This is yet another way EXAIR is helping to make your path to compressed air optimization as painless as possible.

As always if you would like to discuss your application or have questions on how we can help you with your compressed air system, feel free to contact us.

Brian Farno
Application Engineer
Twitter: EXAIR_BF

Cooking: Offroad in a minivan without instructions

Do you like to cook?  I do.  As an engineer, it’s kind of a stress release for me and a welcome change to designing say, a custom air knife.  Sure, there’s a certain satisfaction in seeing that custom Super Air Knife built and perform to spec, but they don’t taste very good.  Or maybe I enjoy cooking because it appeals to my sense of structure.  Following a discrete number of steps to arrive at a prescribed solution.  Of course, sometimes the directions sound a lot easier than they are…

So while on one hand I do try to stick to the recipe when I cook (at least for the most part), I tend to be the kind of guy that will build his entire entertainment center, and in the course of cleaning up the various debris afterward, find a very well-preserved set of directions sealed in the little plastic bag they came in.  And stopping to ask for directions? HA!  I mean hey, I am after all, a guy and some things can’t be changed.  As I often tease my wife ‘I don’t read directions, I WRITE them.’  Of course, occasionally this can lead to problems, or as I like to call it ‘unplanned adventure.’  For example, one time on the way to Florida…

Okay, so that’s not actually me and my family, but we did have a similar experience in South Alabama one time.  And believe me, that’s a story my wife LOVES to remind me of every time I get lost, um, which is never. Right…

So regardless of your take on directions, we here at EXAIR understand you.  And you’ll understand us too.  We write all of our own Installation and Maintenance Instructions, so there’s no ‘mistranslations’ to deal with.  Unlike the set of directions we recently received with a promotional give-away R/C helicopoter…

The last sentence of paragraph b) is my favorite.

So, you’re the recipe following type?  Take a look at our Knowledge Base for a complete library of Installation and Maintenance Instructions (a one time registration gets you permanent access to instructions, 2D drawings and 3D models, a large application database, product Powerpoints and a video library!). Or maybe you like to try to do it on your own first, and only get help as a last possible resort.  Try our online chat or pick up the phone and call us a 1-800-903-9247.  Either way, it’s okay by us.  And we promise, if you do ask for help, we’ll keep it just between you and us…

Dan Preston
Design Engineer