Opportunities to Save On Compressed Air

Since air compressors use a lot of electricity to make compressed air, it is important to use the compressed air as efficiently as possible.  EXAIR has six simple steps to optimize your compressed air system.  (Click HERE to read).  Following these steps will help you to cut your overhead costs and improve your bottom line.  In this blog, I will cover a few tips that can really help you to save compressed air.

To start, what is an air compressor and why does it cost so much in electricity?  There are two types of air compressors, positive displacement and dynamic.  The core components for these air compressors is an electric motor that spins a shaft.  Like with many mechanical devices, there are different efficiencies.  Typically, an air compressor can put out anywhere from 3 SCFM per horsepower to 5 SCFM per horsepower.  (EXAIR settles on 4 SCFM/hp as an average for cost calculations.)  Equation 1 shows you how to calculate the cost to run your air compressor.

Equation 1:

Cost = hp * 0.746 * hours * rate / (motor efficiency)

where:

Cost – US$

hp – horsepower of motor

0.746 – conversion KW/hp

hours – running time

rate – cost for electricity, US$/KWh

motor efficiency – average for an electric motor is 95%.

As an example, a manufacturing plant operates a 100 HP air compressor in their facility.  The cycle time for the air compressor is roughly 60%.  To calculate the hours of running time per year, I used 250 days/year at 16 hours/day.  So operating hours equal 250 * 16 * 0.60 = 2,400 hours per year.  The electrical rate for this facility is $0.08/KWh. With these factors, the annual cost to run the air compressor can be calculated by Equation 1:

Cost = 100hp * 0.746 KW/hp * 2,400hr * $0.08/KWh / 0.95 = $15,077 per year in just electrical costs.

There are two major things that will rob compressed air from your system and cost you much money.  The first is leaks in the distribution system, and the second is inefficient blow-off devices.   To address leaks, EXAIR offers an Ultrasonic Leak Detector.  The Ultrasonic Leak Detector can find hidden leaks to fix. That quiet little hissing sound from the pipe lines is costing your company.

A University did a study to find the percentage of air leaks in a typical manufacturing plant.  For a poorly maintained system, they found on average that 30% of the compressor capacity is lost through air leaks.  Majority of companies do not have a leak preventative program; so, majority of the companies fall under the “poorly maintained system”.  To put a dollar value on it, a leak that you cannot physically hear can cost you as much as $130/year.  That is just for one inaudible leak in hundreds of feet of compressed air lines.  Or if we take the University study, the manufacturing plant above is wasting $15,077 * 30% = $4,523 per year.

The other area to check is air consumption.  A simple place to check is your blow-off stations.  Here we can decide how wasteful they can be.  With values of 4 SCFM/hp and an electrical rate of $0.08/KWh (refence figures above), the cost to make compressed air is $0.25 per 1000 ft3 of air.

One of the worst culprits for inefficient air usage is open pipe blow-offs.  This would also include cheap air guns, drilled holes in pipes, and tubes.  These devices are very inefficient for compressed air usage and can cost you a lot of money.  As a comparison, a 1/8” NPT pipe versus an EXAIR Mini Super Air Nozzle.  (Reference below).  As you can see, by just adding the EXAIR nozzle to the end of one pipe, the company was able to save $1,872 per year.  That is some real savings.

 By following the Six Steps to optimize your compressed air system, you can cut your energy consumption, improve pneumatic efficiencies, and save yourself money.  With the added information above, you can focus on the big contributors of waste.  If you would like to find more opportunities to save compressed air, you can contact an Application Engineer at EXAIR.  We will be happy to help.

John Ball
Application Engineer
Email: johnball@exair.com
Twitter: @EXAIR_jb

Compressed Air Flow Meter With Wireless Capability Makes Monitoring Demand Easy

Would you like the ability to monitor your plants compressed air usage from one convenient location?  If the answer is yes, EXAIR has just the solution to fit your needs, EXAIR’s Digital Flow Meter with Wireless Capability.

wirelessdfmpr2_1670x574

Wireless capability is an option for EXAIR’s Digital Flowmeter’s.  It is the efficient way to monitor your compressed air consumption wirelessly utilizing the ZigBee® mesh network.  This is accomplished by a module located within the meter that transmits data to an ethernet connected gateway.  Each meter has a range up to 100 feet (30 meters), however the ZigBee mesh network protocol is very versatile as it allows data to also be transmitted from meter to meter, effectively extending the distance over which the system can operate.  So large facilities with great distances to cover are not a problem.

The Digital Flowmeter with Wireless Capability is offered in a kit with a wireless output flow meter, wireless to ethernet gateway, drill guide, power supplies for each component, and ethernet cable for gateway connectivity.  These kits are best suited for new installations.  They are also available without a gateway if you are simply adding an additional meter to a pre-existing Gateway in your plant.  EXAIR simplifies this process by configuring each gateway to communicate with the flowmeter to provide the necessary communication for monitoring your system.  Models from 1/2″ to 4″  iron pipe are in stock. 5″, 6″ iron pipe,  copper pipe ranging from 3/4″ to 4″ diameter and aluminum pipe from 25mm to 101mm diameter are available with short lead time as a special product offering.  Each digital flowmeter is calibrated for the pipe size to which it is mounted and the large digital display shows air use in either SCFM or Cubic Meters per Hour.

Digital Flow Meter Kit
Digital Flowmeter w/ Wireless Capability, Gateway, and Drill Guide Kit

Setting up the EXAIR Digital Flow Meter with Wireless Capability is super easy.  After the meter is installed download the graphing software from our website and install on your computer.  There is also a video tutorial posted in the previous blog from Tyler Daniel, Video Blog: EXAIR’s New Wireless Digital Flowmeter Installation.

The Digital Flowmeter with Wireless Capability is designed for permanent or temporary mounting to the pipe.  It requires the user to drill two small holes through the pipe using the optional drill guide which includes the drill bit and locating fixture.  The two flow sensing probes of the flowmeter are inserted into these holes.  The unit seals to the pipe once the clamps are tightened.  No cutting, welding, adjustments or calibration are needed, ever!  If the unit needs to be removed, blocking rings are available for the 1/2″ to 4″  iron pipe sizes from stock with other sizes available on short lead time as special orders.

If you have questions on Digital Flowmeter’s, Digital Flowmeter’s with Wireless Capability or need expert advice on safe, quiet and efficient point of use compressed air products give us a call.   We would enjoy hearing from you!

Steve Harrison
Application Engineer
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Digital Flowmeter Improves Production Scheduling And Upgrade Budgeting

“You can’t manage what you can’t measure” might be the most popular axiom in any process improvement endeavor. And it’s true. We hear it almost every time we discuss a Digital Flowmeter application, and a conversation I just had with a customer was no exception.

Their business is growing, and they’re pushing the limits of their compressed air system. The use compressed air to run their CNC mills in their machine shop, for blow off/cleaning as they assemble products, as well as a variety of pneumatic tools throughout the shop. The CNC machines’ air load was pretty consistent…the rest of the shop; not so much. So they wanted to find out when their compressed air demand peaked, and what it peaked at, in order to make a more informed decision about upgrading their compressor.

From your Digital Flowmeter to your computer screen, the USB Data Logger tells you how much air you’re using…and when you’re using it!

So, they purchased a Model 9095-DAT Digital Flowmeter for 2″ SCH40 Pipe, with USB Data Logger. They installed it immediately, with the USB Data Logger set to record once a second…this told them their consumption at any given time over the course of the day. Every day at closing time, the shop manager pulls the USB Data Logger from the Digital Flowmeter and transfers the data to his computer. After just a few days, he knew exactly how much air they were using…and exactly when they were using it. He’s now using this data (in the short term) to plan certain operations around peak scheduling, and (in the long term) to know what they’re looking at for their next air compressor.

Do you know as much about your compressed air usage as you should? If you’d like to talk about how to measure…and manage…your air consumption, give me a call.

Russ Bowman
Application Engineer
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Can Counting Carbs Help in Your Compressed Air System?

Breakfast Cereal
Breakfast Cereal

Have you ever counted the amount of carbs that you eat?  People typically do this to lose weight, to become healthier, or for medical reasons like diabetes.  Personally, I like to eat cereal in the morning.  I will pull a box of cereal down from the cupboard and look at the Total Carbs field.  One morning, I looked at a box of gluten-free rice flakes and compared it to a peanut butter nugget cereal.  I noticed that the carbs were very similar.  The rice cereal had 23 grams of total carbs while the peanut butter nuggets had only 22 grams of total carbs.  Then I looked at the serving size.  The rice cereal had a serving size of 1 cup while the nuggets only had a serving size of ¾ cups.  So, in comparison, for one cup of nugget cereal, the total amount of carbs was 27.5 grams.  Initially, I thought that they were similar, but the peanut butter nugget was actually 20% higher in carbs.  This same “misdirection” occurs in your compressed air system.

Here is what I mean. Some manufacturers like to use a lower pressure to rate their products.  This lower pressure makes it seem like their products will use less compressed air in your system.  But, like with the serving sizes, it can be deceiving.  It is not a lie that they are telling, but it is a bit of misconception.  To do an actual comparisons, we have to compare the flow rates at the same pressure (like comparing the carbohydrates at the same serving size).  For example, MfgA likes to rate their nozzles at a pressure of 72.5 PSIG.  EXAIR rates their nozzles at 80 PSIG as this is the most common pressure for point-of-use equipment.  You can see where I am going with this.

To compare nozzles of the same size, MfgA nozzle has a flow rate of 34 SCFM at 72.5 PSIG, and EXAIR model 1104 Super Air Nozzle has a rating of 35 SCFM at 80 psig. From an initial observation, it looks like MfgA has a lower flow rating.  To do the correct comparison, we have to adjust the flow rate to the same pressure.  This is done by multiplying the flow of MfgA nozzle by the ratio of absolute pressures.  (Absolute pressure is gage pressure plus 14.7 PSI).  The ratio of absolute pressures is:  (80PSIG + 14.7) / (72.5PSIG + 14.7) = 1.09.  Therefore; the flow rate at 80 PSIG for MfgA nozzle is now 34 SCFM * 1.09 = 37 SCFM.  Now we can compare the flow rates for each compressed air nozzle.  Like adjusting the serving size to 1 cup of cereal, the MfgA will use 9% more compressed air in your system than the EXAIR model 1104 Super Air Nozzle.  This may not seem like much, but over time it will add up.  And, there is no need to waste additional compressed air.

Family of Nozzles
Family of Nozzles

The EXAIR Super Air Nozzles are designed to entrain more ambient air than compressed air needed. This will save you on your pneumatic system, which in turn will save you money.  The other design features gives the EXAIR Super Air Nozzle more force, less noise, and still meet the OSHA compliance.

If you want to run a healthier compressed air system, it is important to evaluate the amount of compressed air that you are using. To do this correctly, you always want to compare the information at the same pressure.  By using the EXAIR Super Air Nozzles in your compressed air system, you will only have to worry about your own weight, not your pneumatic system.

John Ball
Application Engineer
Email: johnball@exair.com
Twitter: @EXAIR_jb

 

Picture: Breakfast Cereal by Mike Mozart Creative Commons Attribution 2.0 Generic License