Tag: under pressure

Pressure Sensing Flow Meters

Published on by Jordan T ShouseLeave a comment

If you are looking to add some control to your compressed air system, one of the first things you need to do is understand the baseline for where your system is. This includes, of course, the volume of compressed air you are providing, but also the pressure at which your system is seeing as well. This is especially important when you have an application that is very pressure dependent like a CNC mill tool changer.

The Pressure Sensing Digital Flowmeters are available from 2″ Sched. 40 Iron Pipe up to 8″ Sched. 40 Iron Pipe.  As well as 2″ to 4″ copper pipes.  These will be read out and with additional data logger as well, so you can track the pressure over the course of every shift, and even days.

Generating a pressure and consumption profile of a system can help to pinpoint energy wasters such as timer-based drains that are dumping every hour versus level-based drains that only open when needed. A scenario similar to this was the cause of an entire production line being shut down nearly every day of the week for a local facility until they installed flowmeters and were able to narrow the demand location down to a filter baghouse with a faulty control for the cleaning cycle.

If you’re serious about getting the most out of your compressed air use, the very first step in EXAIR’s Six Steps To Optimizing Your Compressed Air System is literally a great place to start.

Six Steps to Optimizing Your Compressed Air System

Here are some blogs on the other steps!

Step #1- Step 1 – Measure your Air

Step #2- Step 2 – Finding and fixing leaks

Step #3- Step 3 – Use Efficient and Quiet Engineered Products

Step #4- Step 4 – Turn the air off while its not in use

Step #5- Step 5 – Install Secondary Receiver Tanks

Step #6 – Step 6 – Control the air pressure

If you would like to discuss the best digital flowmeter for your system and to better understand the benefits of pressure sensing, please contact us. To find out more, give me a call.

Jordan Shouse
Application Engineer

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Tool Changer Photo courtesy of Luke Gilliam via creative commons

Air Knives & What You Don’t Normally See

Published on by Brian FarnoLeave a comment

In the day-to-day life of an Application Engineer here at EXAIR, you get to speak about every single one of our engineered solutions, and sometimes you find yourself getting into discussions about items we don’t make and even some new ways to use products that we haven’t showcased. The run-of-the-mill applications for Super Air Knives are cleaning, cooling, or drying materials off, whether it be stationary and the knife moves or if the product is moving and proceeding through the sheet of air produced by the Super Air Knife. No matter which of these applications, the one thing in common is that they are all supplying the Super Air Knife with compressed air. Okay, some use compressed nitrogen, and they are few and far between. There is another motive material that can be used that isn’t a gas and that doesn’t get discussed too much; water!

Just last week, I was speaking with a customer who was struggling with a point of their application where they needed a waterfall of liquid and didn’t want to use liquid atomizing spray nozzles because they were required to have a continuous “sheet” of liquid in order to have optimal performance. They knew the Super Air Knives worked great on their drying section, so they called and asked how they do with water?

Well, the answer is they do pretty well considering they were designed for compressed air, which is compressed and expands rapidly to atmospheric conditions and helps with our performance, while water cannot be compressed, only pressurized. The good news is we do have some data and pictures from tests on something like this. So I pulled out the information I had and shared it with the customer.

  • .004″ Gap – 17 psig inlet pressure
  • .012″ Gap – 17 psig inlet pressure

As you can see, increasing the gap a little bit and keeping a good supply lends to a nice stream at lower operating pressures, not even full city line water pressure. While we tested numerous gaps and inlet pressures, some of the best flows were from 17 psig inlet pressure and with a .004″ and up to a .012″ gap. The customer in this case was happy enough that they decided to get a knife and shim sets in to test under our 30-day guarantee, and it turns out they were getting the performance they needed with the .004″ thick gap and about 15 psig inlet pressure.

While the point of this was to showcase how well a product works with something other than compressed air that it wasn’t designed around, I hope to also emphasize that we truly have tested a vast number of variables with most of our products. If we don’t have test data on what you are thinking, as long as it is safe, and we have the ability, we will conduct a test. If we think the best thing to do is for you to get it in and test it, then we will back up our stock product offering with a 30-day guarantee. If we know it isn’t going to be a good fit, we will also tell you that.

If you want to discuss anything revolving around the point of use using compressed air or pressurized liquid being used in a process within your facility, please contact an Application Engineer today!

Brian Farno, MBA – CCASS Application Engineer

BrianFarno@EXAIR.com
@EXAIR_BF

Pressure Monitoring Not Just For Air Systems

Published on by Brian FarnoLeave a comment

This past weekend we celebrated Labor Day. My family and I had the pleasure of going to a friend’s property and parking an RV to “glamp” for the weekend. The trip is only about 3-1/2 hours from our homes and when traveling in the RV it is a slow and steady wins the race kind of trip. One of the first things I do when we are prepping for the trip is to check tire pressure. Then, the last thing I do before we leave is check tire pressures.

While at their property we did the same on all of their vehicles, two side-by-side UTVs, and their boat trailer. When looking at each of these, almost all of them were low. Now, these items all sit more than they are used and only see movement maybe once a month. The weather here in the area, including Kentucky has been getting cooler in the evenings which causes the air in tires to start to take up less space and so the pressure drops. Well, after checking and filling, we went out and everything was great, until it wasn’t. When we loaded up the boat we noticed one of the tires was nearly on the rim of the trailer. With no tools on hand and a short drive, we elected to make the drive and inspect when we got back to home ground rather than in a public parking lot where someone had already offered to help if need be. Once we arrived, we inspected the tire and found no obvious signs for it to be so low on pressure. We filled it up again and let it sit for the night. After breakfast the next day we found the tire was still holding air so we assumed that when we checked the pressure initially it was at a good pressure and by doing so something must have stuck in the valve causing it to have a slow leak. Once that was seated and good, the tire held air, and we were good to roll for another day.

This made me realize how important pressure monitoring is on tires for certain vehicles and led me to install a continuous pressure monitoring system on the RV that we took. Being able to monitor tire temperature and pressure is critical and catching low pressure before it causes other issues can help reduce damage or catastrophic failure significantly. This also all made me connect my thoughts to the EXAIR Digital Flowmeters which are available with pressure sensing capabilities. These can easily be installed into a system and then be used to monitor your industrial system and potentially see issues before catastrophic failures or downtimes due to a loss of compressed air.

If you want to discuss what a Pressure Sensing Digital Flowmeter can do in your facility or even if you want to troubleshoot why you are seeing a drop in performance and how to even go about troubleshooting your entire air system, don’t hesitate to contact an Application Engineer.

Brian Farno
Application Engineer
BrianFarno@EXAIR.com
@EXAIR_BF

Don’t Fall Victim To Undersized Piping

Published on by Brian FarnoLeave a comment

Pressure drops, incorrect plumbing, undersized piping, insufficient flow; if you hear these terms from tech support of your point of use compressed air products or from your maintenance staff when explaining why a process isn’t working then you may be a victim of improper compressed air piping selection.
Often time this is due to a continued expansion of an existing system that was designed around a decade old plan. It could also come from a simple misunderstanding of what size of piping is needed and so to save some costs, smaller was used. Nonetheless, if you can understand a small number of variables and what your system is going to be used for, you can ensure the correct piping is used. 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 are shown below.

  • Minimum Operating Pressure Allowed (psig) – Lowest pressure permitted by any demand side point of use product.
  • System Pressure (psig) – Safe operating pressure that will account for pressure drops.
  • Flow Rate (SCFM) of demand side (products needing the supplied compressed air)
  • 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
BrianFarno@EXAIR.com
@EXAIR_BF