Keep Your Pneumatics “Healthy” and “Running Like a Brand New Car”

Compressed air systems are used in facilities to operate pneumatic systems, and these systems are vital for industries.  So, it is important to keep them running.  The system can be segregated into three different sections; the supply side, the demand side, and the distribution system.  I like to represent these sections as parts of a car.  The supply side will be the engine; the distribution system will be the transmission; and, the demand side will be the tires.  I will go through each section to help give tips on how to improve the “health” of your pneumatic system.

From the supply side, it will include the air compressor, after-cooler, dryer, and receiver tank that produce and treat the compressed air.  They are generally found in a compressor room somewhere in the corner of the plant.  The air compressor, like the engine of your car, produces the pneumatic power for your plant, and needs to have maintenance to keep it working optimally.  The oil needs to be changed, the filters have to be replaced, and maintenance checks have to be performed.  I wrote a blog that covers most of these items, “Compressed Air System Maintenance”.

To connect the supply side to the demand side, a distribution system is required.  Distribution systems are pipes which carry compressed air from the air compressor to the pneumatic devices.  Just like the transmission on the car, the power is transferred from the air compressor to your pneumatic products.

Maintenance is generally overlooked in this area.  Transmissions have oil which can be detected if it is leaking, but since air is a gas, it is hard to tell if you have leaks.  Energy is lost from your pneumatic “engine” for every leak that you have.  So, it is important to find and fix them.  A study was conducted within manufacturing plants about compressed air leaks.  They found that for plants without a leak detection program, up to 30% of their compressed air is lost due to leaks.  This will be equivalent to running on only 6 cylinders in a V-8 engine.

EXAIR offers the Ultrasonic Leak Detector to find those pesky leaks.  It makes the inaudible “hiss”; audible.  It can detect leaks as far as 20 feet (6m) away with the parabola attachment, and can find the exact location of the leak to be fixed with the tube attachment.

Another area for discussion with the distribution system is contamination like rust, oil, water, and debris.  Compressed air filters should be used to clean the compressed air that supplies your pneumatic products. They can remove the debris for your pneumatic products to have a long life.  You can read about the EXAIR compressed air filters here, “Preventative Maintenance for EXAIR Filters”.

The third section is the demand side.  So, you have an engine that makes the power, the transmission to transfer that power, and the tires to use that power safely and efficiently.  Many managers miss the importance of the demand side within their pneumatic system.  If you are using blow-off devices like open pipes, coolant lines, copper tubes, or drilled pipe; it will be like running your car on flat tires.  It is very unsafe as well as reducing gas mileage.  To improve safety and efficiency, EXAIR has a line of Super Air Nozzles and Super Air Knives.  Not only will it increase your “gas mileage” to save you money, but they also will keep your operators safe.

In this analogy, you can have a high-performance engine and a durable transmission, but if your tires are bald, flat, or cracked; you cannot use your car safely and efficiently.  The same thing with your compressed air system.  You have to optimize your blow-off devices to get the most from your pneumatic system.  EXAIR is a leader in engineered blow-off devices for efficiency and safety.  So, if you want to improve the “health” of your pneumatic system, you should begin at how you are using your compressed air on the demand side.  EXAIR has Application Engineers that will be happy to help you in trying to keep your pneumatic system running like a “brand new car”.

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

 

Photo: Ford Mustang Roadster by openclipart-VectorsPixabay License

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

Replacing Unsafe Open Pipes with High Pressure Air Nozzles

Open pipes present unsafe working conditions and continuous pressure drops in compressed air systems

Let’s talk for a minute about pressure drops. Normally when the topic of pressure drops is raised, it comes in a context related to proper plumbing and volume supply.  (If there are significant pressure drops within a compressed air system, especially those which reduce volume flow, problems will arise with compressed air driven devices.)

But, there is another important aspect of pressure drops which relates to open pipe blow-off, a common homemade remedy for blow-off applications. This aspect has to do with the available compressed air pressure at the exhausting point from the pipe or nozzle.  In the case of an open pipe, it requires so much compressed air volume that, there can be a continuous pressure drop from the compressor to the open pipe.  However, when a nozzle is installed onto a compressed air pipe, there is a restriction to the flow and the entire pressure drop takes place across the nozzle.

What this means for the blow-off solution is a higher velocity blow-off and a more powerful force from the airflow, with less compressed air consumption.

To think of it another way, imagine the flow of water from your garden hose. If the hose is open-ended and the water is fully on, the flow will be high and the force will be low.  But, when you install a nozzle onto the end of the hose the flow reduces and the force increases.  This is because the pressure drop in the system is taking place across the nozzle rather than the entire system.

This type of a scenario was taking place in the image shown at the top of this blog. The plastic lines connected to the aluminum manifold were fully open on the end, providing a continuous pressure drop and poor blow-off performance.  This, coupled with the maximum operating pressure of similar types of hose being 35 PSI, led to a poor performance in this application.

The solution for this customer was to replace these open pipe blow-offs with EXAIR model 1126 Flat Super Air Nozzles and 12″ Stay Set Hoses, model 9262. The flat airflow of the 1126 Super Air Nozzles provide a highly efficient and forceful blow-off, and the Stay Set Hoses allow for articulation of the nozzles into any position needed.

By replacing these open pipes this customer saved compressed air, added safety (open pipes present an operating hazard per OSHA Standard CFR 1910.242(b)), and improved the performance of their operation.

If you have a similar application or would like to speak with someone about increasing the efficiency of your compressed air applications, contact an EXAIR Application Engineer.

Lee Evans
Application Engineer
LeeEvans@EXAIR.com
@EXAIR_LE