## Consider these Variables When Choosing Compressed Air Pipe Size

Here on the EXAIR blog we discuss pressure drops, correct plumbing, pipe sizing, and friction losses within your piping system from time to time.   We will generally even give recommendations on what size piping to use.  These are the variables that you will want to consider when selecting a piping size that will suit your need and give the ability to expand if needed.

The variables to know for a new piping run are as follows.

• Flow Rate (SCFM) of demand side (products needing the supplied compressed air)
• System Pressure (psig) – Safe operating pressure that will account for pressure drops.
• Minimum Operating Pressure Allowed (psig) – Lowest pressure permitted by any demand side point of use product.
• Total Length of Piping System (feet)
• Piping Cost (\$)
• Installation Cost (\$)
• Operational Hours ( hr.)
• Electical Costs (\$/kwh)
• Project Life (years) – Is there a planned expansion?

An equation can be used to calculate the diameter of pipe required for a known flow rate and allowable pressure drop.   The equation is shown below.

A = (144 x Q x Pa) / (V x 60 x (Pd + Pa)
Where:
A = Cross-Sectional are of the pipe bore. (sq. in.).
Q = Flow rate (cubic ft. / min of free air)
Pa = Prevailing atmospheric absolute pressure (psia)
Pd  = Compressor discharge gauge pressure (psig)
V = Design pipe velocity ( ft/sec)

If all of these variables are not known, there are also reference charts which will eliminate the variables needed to total flow rate required for the system, as well as the total length of the piping. The chart shown below was taken from EXAIR’s Knowledge Base.

Once the piping size is selected to meet the needs of the system the future potential of expansion should be taken into account and anticipated for.   If no expansion is planned, simply take your length of pipe and start looking at your cost per foot and installation costs.    If expansions are planned and known, consider supplying the equipment now and accounting for it if the additional capital expenditure is acceptable at this point.

The benefits to having properly sized compressed air lines for the entire facility and for the long term expansion goals makes life easier.   When production is increased, or when new machinery is added there is not a need to re-engineer the entire system in order to get enough capacity to that last machine.   If the main compressed air system is undersized then optimal performance for the facility will never be achieved.   By not taking the above variables into consideration or just using what is cheapest is simply setting the system up for failure and inefficiencies.   All of these considerations lead to an optimized compressed air system which leads to a sustainable utility.

Brian Farno
Application Engineer Manager
BrianFarno@EXAIR.com
@EXAIR_BF

## Never Think Your Idea Will Not Be Heard

The above title proved very true in a work experience of my father’s. After working in the mill for several years, he drew up a new piece of process equipment which would eventually turn in to something that they put in place on the production line.   This was all done from his idea that he was able to place on a scrap piece of paper as a drawing.   While he wasn’t the decision maker in the process, he was the person who saw what kind of impact this device could have and knew the people he had to get the information to.

That brings me to the topic of this blog, don’t ever think an idea is too small to warrant a reward.  This can ring true throughout any type of application, including compressed air.  There have been instances where a maintenance worker, or even a new operator, have called in to speak to me here asking what can they do to lower the noise in the work area when they are using the hand held blow gun the company supplies.   After talking to them about what they are trying to achieve with the blow gun and how much air they are currently using, we generally find that they can save a good amount of compressed air, lower the noise level, and become OSHA compliant, all by changing this one simple tool.   Once they have all the benefits that their company will see from implementing our engineered solution, they can then propose this to the decision makers.

For the most part, companies will at the very least entertain ideas like this.  When you back that idea up with some relevant data on how much money the company will save, or the fact that is will make the work environment safer and more enjoyable, then you will more than likely get a little more attention.  The main point is to ensure that you are getting that information to the correct person and that you have the correct information.   That is one of the many reasons that EXAIR has a full team of Application Engineers who can help you identify how much air you might be using, what products will fit the need, and what kind of benefits your company will see.   On top of all the information that we have available for free, we even offer the chance to get compensation for sharing application data with us.

That’s right, we will compensate you for sharing your cost savings, sound level reductions or application improvements, with us.  This is all possible through our Case Study program.  All you have to do to find out more is contact any Application Engineer.  We simply need some photographs of the application and some quantitative data for the benefits you have gained.  Don’t know what your current device is using, take advantage of our EXAIR Efficiency Lab, that will give us a good amount of information we need to then, help you solve a problem as well as produce a Case Study.

Brian Farno
Application Engineer Manager
BrianFarno@EXAIR.com
@EXAIR_BF

## The Rate Is Right?

This morning, we played our own little version of a popular segment of the game show “The Price Is Right,” right here in the Application Engineering department. Brian Farno (our manager and host extraordinaire) presented us with a question (that he already knew the answer to after speaking with a current customer):

What would you expect the conveyance rate to be, for an EXAIR Model 6083 1-1/2” Aluminum Line Vac, conveying hot-melt glue pellets, across a total distance of 15 feet vertically & 100 feet horizontally? (And please note we normally have a bulk density in lbs./ft3 and/or other associated information about pipe bends, product shape etc. – but we took our best shot at it anyway).

We didn’t have those cool podiums to stand behind that recorded our answers on the screen, but here’s what we came up with:

Russ Bowman: 5 lbs per minute
Dave Woerner: 10 lbs per minute
Justin Nicholl: 8 lbs per minute
Professor Penurious: 1 lb per minute (Insert \$1 bid joke here)

Now, we had all referenced our wealth of data charts for conveyance rates with our Line Vac product series. We used several very different materials over a few different lengths/heights, and use that data to estimate what a user might expect to see, based on how close their application is to our actual test conditions. I actually used this data for my answer – a 1-1/2” Aluminum Line Vac conveyed tumbling media (64 lbs/cu ft; the lowest bulk density material we tested for) at a rate of about 5-1/2 lbs/minute, going 20 feet vertically.

Turns out, Dave came the closest without going over: they were actually getting a little over 11 lbs per minute…again, going 15 feet up and 100 feet over. The user was so pleased with the results, they’re incorporating a Line Vac in a similar application, involving hot-melt glue pillows. We’ve now added their data to our database and are pleased with the knew knowledge.

If you have an application involving hopper loading, bulk material conveying, chip removal, parts transfer, etc., and would like to find out how an EXAIR Line Vac can help, give me a call. We might both be impressed with the results. Come on down!

Professor Penurious, by the way, is still concentrating on hosting the game shows.  Stay tuned…

Russ Bowman
Application Engineer
(513)671-3322 local
(800)923-9247 toll free
(513)671-3363 fax
Visit us on the web

## Compressed Air and Halloween Candy

Tomorrow night is Halloween. I live in a suburban subdivision with a high ratio of young families, which makes for a target-rich environment for Trick or Treaters…my boys included. We’ll allow them to enjoy a sensible portion of their haul tomorrow night, and the rest will go into the cabinet over the stove for rationing out over the next week or so.

First to disappear will be the brand name chocolates, candy bars, peanut butter cups, etc. The occasional bags of pretzels/salty snacks will find their way into school lunch bags quickly. Novelty lollipops – the kind with candy or gum in the middle – go fast in my house, but only after the chocolate has been completely exhausted. Individual hard candies linger at the bottom until they’re forgotten about, and eventually get thrown away the next time we need one of those pans we keep in that cabinet…usually when we’re preparing Thanksgiving dinner.

One of the trade publications I read regularly is “Compressed Air Best Practices” Magazine. Every month, there are featured articles that highlight how someone just saved a TON of compressed air by applying various methods and fixes to their systems. Understandably, the opportunities for the largest savings are the most popular…let’s call these the “brand name chocolates.” Common examples of this are:

• Fixing leaks – I know of a company that saved a million SCF per year this way. (Spoiler alert: it was us.)
• Replacing open ended blow offs with engineered products. (Spoiler alert again: we’re the undisputed industry leader for this.)

Of course, you can’t manage what you can’t measure. If you’re serious about efficiency, you’ve already got flow meters in place. If not, it’s time for a look at what’s available, and how much of a benefit you’ll get from knowing what your usage is at any given time. Continuing with my candy surplus analogy, these could be considered the novelty lollipops. Departing from the analogy, though, this should be done first (OK; it’s not a perfect analogy). An EXAIR Digital Flowmeter will give you instant, accurate indication of your air usage, and you can make a “before/after” comparison, once those leaks are fixed and your blow offs are upgraded.

Lastly, don’t forget about regular maintenance. Our USB Data Logger is a great addition to the Digital Flowmeter – it allows you to track your usage over time. Those leaks you just fixed weren’t there when the system was new. If you start to see your usage creeping up, you’ll want to find out why. Our Ultrasonic Leak Detector is a great tool for periodic checks. Use it to find any new leaks that pop up, and you’ll stop throwing away compressed air like it was candy.

Russ Bowman
Application Engineer
EXAIR Corporation
(513)671-3322 local
(800)923-9247 toll free
(513)671-3363 fax
Web: http://www.exair.com
Blog: http://blog.exair.com/