Summer is my favorite time of year. Warm weather, hanging out by the pool, and enjoying the outdoors (weather permitting of course). It’s also the time of year when my favorite holiday occurs, Independence Day. EXAIR will be closed on July 4th in celebration of Independence Day. On this day 243 years ago the Declaration of Independence was adopted, marking the official legal separation of the Thirteen Colonies from Great Britain.
Although today we celebrate on July 4th, Congress actually voted to declare independence two days earlier on July 2nd. If it were up to John Adams, that would be the date we commemorate to this day. He wrote in a letter to his wife that this would be the most memorable day in the history of America, to be celebrated by pomp and parade, games, sports, guns, bells, bonfires, and illuminations from one end of this continent to the other. In protest of July 4th being designated a federal holiday, he was reported to turn down invitations to appear. Coincidentally, both he and Thomas Jefferson both passed away on July 4, 1829 on the 50th anniversary of the adoption of the Declaration of Independence.
I imagine the celebrations looked quite a bit different back then, but today many of us will spend time with our family and friends enjoying some BBQ. Parades and firework shows are also in abundance as we celebrate together as a country in unison.
“America was not built on fear. America was built on courage, on imagination and an unbeatable determination to do the job at hand.” – Harry S. Truman
The very same can be said of EXAIR, built on the courage, imagination and determination of our late founder Roy Sweeney. Without his willingness to take risks and build his version of the American Dream, we would have never come to be.
So while we celebrate, hot dog in hand, take a moment to reflect on what it means to be an American. Enjoy your right to life, liberty, and the pursuit of happiness. To all of my fellow Americans on behalf of EXAIR, Happy Birthday to US!
Leaks in a compressed air system can be a substantial source of wasted energy. A facility that hasn’t maintained their compressed air system will likely have a leak rate around 20-30% of the total air production. But with a leak detection plan you can reduce air leaks to less than 10% of the compressor output.
Along with the energy waste, leaks will contribute to higher operating cost. Leaks cause a drop in system pressure, which can make air tools operate poorly, harming production cost and time. In addition, by forcing the equipment to cycle more often, leaks shorten the life of almost all system equipment, including the compressor. Increased running time can also lead to added maintenance and increased downtime. Finally, leaks can lead to adding unnecessary compressor volume.
Since air leaks are almost impossible to see, other methods must be used to locate them. The best way to detect leaks is to use an ultrasonic acoustic detector, Like EXAIRUltrasonic Leak Detector (ULD). This unit can recognize the high frequency hissing sounds associated with air leaks. A person using the ULD only needs to point it in the direction of the suspected leak. When a leak is present, an audible tone can be heard with the use of the head phones, and the LED display will light. Testing various unions, pipes, valves and fittings of a complete system can be done quickly and effectively at distances up to 20’ away!
The advantages of ultrasonic leak detection include flexibility, speed, ease of use, the ability to test the system while machines are running, and the ability to find a wide variety of leaks. They involve very little training, operators often become competent after 10 minutes of training.
Due to the nature of ultrasound, it is directional in transmission. For this reason, the signal is loudest at its source. By scanning around a test area, it is possible to very quickly target in on a leak site and pin point its exact location. For this reason, ultrasonic leak detection is not only fast, it is also very accurate.
An active leak prevention program will embrace the following components: identification, tracking, repair, verification, and employee participation. All facilities with a compressed air system should establish an aggressive leak reduction program. A team involving managerial representatives from production should be formed to carry out this program.
A leak prevention program should be part of an overall program intended to improve the performance of compressed air systems. Once the leaks are found and repaired, the system should be started from the beginning until all leaks are addressed.
A good compressed air system leak repair program is very important in maintaining the efficiency, reliability, stability and cost effectiveness of any compressed air system.
“First a Plant Engineer or Maintenance Supervisor must realize that leak repair is a journey, not a destination. An ongoing compressed air leak monitoring and repair program should be in place in any plant that has a compressed air system.” Explains Paul Shaw, a General Manager for Scales Industrial Technologies’ Air Compressor Division, and an Advanced CAC Instructor, “Leak identification and remediation with a high quality repair can lead to substantial energy savings that typically has a very rapid payback, usually a year or less. In the hundreds of leak audits and repairs that we have done we’ve found that the quality of the repair is critical to ensuring the customer receive the most value for his investment and that the leak remains repaired for as long as possible. From there, constantly monitoring for compressed air leaks and repairing them as they occur can help the plant continue to reap the energy benefits.”
To discuss your application and how an EXAIR Intelligent Compressed Air Product can help your process, feel free to contact EXAIR and myself or one of our Application Engineers can help you determine the best solution.
EXAIR has been manufacturing Intelligent Compressed Air Products since 1983. They are engineered with the highest of quality, efficiency, safety, and effectiveness in mind. Since compressed air is the source for operation, the limitations can be defined by its supply. With EXAIR products and pneumatic equipment, you will need a way to transfer the compressed air from the air compressor. There are three main ways; pipes, hoses and tubes. In this blog, I will compare the difference between compressed air hoses and compressed air tubes.
The basic difference between a compressed air hose and a compressed air tube is the way the diameter is defined. A hose is measured by the inner diameter while a tube is measured by the outer diameter. As an example, a 3/8” compressed air hose has an inner diameter of 3/8”. While a 3/8” compressed air tube has an outer diameter that measures 3/8”. Thus, for the same dimensional reference, the inner diameter for the tube will be smaller than the hose.
Why do I bring this up? Pressure drop… Pressure Drop is a waste of energy, and it reduces the ability of your compressed air system to do work. To reduce waste, we need to reduce pressure drop. If we look at the equation for pressure drop, DP, we can find the factors that play an important role. Equation 1 shows a reference equation for pressure drop.
DP = Sx * f * Q1.85 * L / (ID5 * P)
DP – Pressure Drop
Sx – Scalar value
f – friction factor
Q – Flow at standard conditions
L – Length of pipe
ID – Inside Diameter
P – Absolute Pressure
From Equation 1, differential pressure is controlled by the friction of the wall surface, the flow of compressed air, the length of the pipe, the diameter of the pipe, and the inlet pressure. As you can see, the pressure drop, DP, is inversely affected by the inner diameter to the fifth power. So, if the inner diameter of the pipe is twice as small, the pressure drop will increase by 25, or 32 times.
Let’s revisit the 3/8” hose and 3/8” tube. The 3/8” hose has an inner diameter of 0.375”, and the 3/8” tube has an inner diameter of 0.25”. In keeping the same variables except for the diameter, we can make a pressure drop comparison. In Equation 2, I will use DPt and DPh for the pressure drop within the tube and hose respectively.
DPt / DPh = (Dh)5 / (Dt)5
DPt – Pressure drop of tube
DPh – Pressure Drop of hose
Dh – Inner Diameter of hose
Dt – Inner Diameter of tube
Thus, DPt / DPh = (0.375”)5 / (0.25”)5 = 7.6
As you can see, by using a 3/8” tube in the process instead of the 3/8” hose, the pressure drop will be 7.6 times higher.
At EXAIR, we want to make sure that our customers are able to get the most from our products. To do this, we need to properly size the compressed air lines. Within our installation sheets for our Super Air Knives, we recommend the infeed pipe sizes for each air knife at different lengths.
There is also an excerpt about replacing schedule 40 pipe with a compressed air hose. We state; “If compressed air hose is used, always go one size larger than the recommended pipe size due to the smaller I.D. of hose”. Here is the reason. The 1/4” NPT Schedule 40 pipe has an inner diameter of 0.364” (9.2mm). Since the 3/8” compressed air hose has an inner diameter of 0.375” (9.5mm), the diameter will not create any additional pressure drop. Some industrial facilities like to use compressed air tubing instead of hoses. This is fine as long as the inner diameters match appropriately with the recommended pipe in the installation sheets. Then you can reduce any waste from pressure drop and get the most from the EXAIR products.
With the diameter being such a significant role in creating pressure drop, it is very important to understand the type of connections to your pneumatic devices; i.e. hoses, pipes, or tubes. In most cases, this is the reason for pneumatic products to underperform, as well as wasting energy within your compressed air system. If you would like to discuss further the ways to save energy and reduce pressure drop, an Application Engineer at EXAIR will be happy to assist you.
As mentioned in my post last week. The supply side of compressed air systems within a facility is critical to production. The quality of air produced by your compressor and sent to the demand side of the system needs to be filtered for both moisture and particulate. One method to dry the air, that is the topic for this blog, is deliquescent type dryers.
These dryers operate like an adsorbent dryer such as a desiccant medium dryer. The main variance is that the drying medium (desiccant) actually undergoes a phase change from solids to liquids. Because of this the material is used up and cannot be returned to its original state for reuse. The liquids formed by the desiccant dissolving in the removed water vapor are then filtered out of the air stream before it is passed on to the demand side of the air system.
There are many compounds that are used to absorb the moisture in the wet compressed air. A few options are potassium, calcium, or sodium salts and many that contain a urea base. The desiccant compound must be maintained at a minimum level for the dryer to contain enough media to successfully dry the air.
These dryers are generally a single tank system that is fed with compressed air from a side port near the bottom of the tank. The air then travels up past drip trays where the desiccant and water mixture fall and ultimately ends up in the bottom of the tank. The air then goes through a material bed that must be kept at a given level in order to correctly absorb the moisture in the air. The dry air is then pushed out the top of the tank.
As the desiccant material absorbs the liquid from the compressed air flowing through the tank it falls onto the drip trays and then into the bottom of the tank where it is drained out of the system. This process can be seen in the image below.
The dew point that this style dryer is able to achieve is dependent on several variables:
Compressed air temperature
Compressed air pressure / velocity
Size and configuration of the tank
Compression of the absorption media
Type of absorption media and age of media
These dryers are simplistic in their design because there are no moving parts as well as easy to install and carry a low startup cost.
Some disadvantages include:
Dewpoint range 20°F – 30°F (Again this is according to the media used.)
Dissolved absorption material can pose a disposal issue as it may not be able to be simply put down a drain
Replacement of the absorption material
Even with disadvantages the ability to supply the demand side of a compressed air system for a production facility is key to maintaining successful operations. If you would like to discuss any type of compressed air dryer, please contact us.
VariBlast Compact Safety Air Guns provide a variable flow through the pull of the trigger. A light pull provides a breeze while a heavy pull provides a powerful blast. It has a smaller frame than our Soft Grip or Heavy Duty air guns, is lightweight and designed to utilize any of our 1/8 NPT air nozzles for general duty industrial applications.
This video shows how to install the VariBlast Valve Rebuild Kit, part number 902001 – to rebuild any VariBlast Compact Safety Air Gun that, through use, has become worn.
If you have questions about installing the VariBlast Valve Rebuild Kit or to discuss any of the 15 different EXAIR Intelligent Compressed Air® Product lines, feel free to contact EXAIR and one of our Application Engineers can help you.
EXAIR has been manufacturing Intelligent Compressed Air Products since 1983. In that time, we have engineered many new products for new and existing markets that had better efficiency, versatility, and effectiveness. To gauge how a new product is received by your peers, we like to send them to different committees for evaluations. This year, we sent our VariBlast Safety Air Gun to Plant Engineering to compete against other new products in the manufacturing and non-manufacturing industries. In the compressed air category, the EXAIR VariBlast Safety Air Gun won the Silver Award at the Plant Engineering Product of the Year event.
How was EXAIR able to achieve such a prestigious award? Well, let me tell you how our newest safety air gun was able to receive this award. I will discuss the features and benefits with the VariBlast Safety Air Guns, so you can decide for yourself.
To start, the unique feature that sets the VariBlast apart from other small air guns is the force variability. Unlike the “all or nothing” blowing forces with most air guns, this valve is designed to control the opening to allow for a variable force with the same nozzle. This will help you to not “overuse” your compressed air blowing. The VariBlast Safety Air Gun is made from a durable cast aluminum construction for tough industrial use. It has a rugged ergonomic grip with a user-friendly trigger. The compressed air inlets are located in two different positions to best fit your application. They have an easy storage handle to hang the Safety Air Gun nearby. In addition to the VariBlast Safety Air Gun, EXAIR has options to enhance the features and benefits. Here is a list of them:
Air Nozzles can make or break an air gun in safe, efficient and effective use. EXAIR Air Nozzles are OSHA compliant for noise and dead-end pressure. We offer nine different air nozzles with the VariBlast Safety Air Gun; making it very effective for a wide range of applications.
OSHA 1910.242(b) requires chip guarding when compressed air is used for cleaning. EXAIR offers Chip Shields with the VariBlast Safety Air Guns to meet this requirement. They are made from a polycarbonate disc which is practically unbreakable. It protects the operator from any blow back of shavings and coolant. They come standard with a durable rubber grommet that squeezes onto the extensions and can be adjusted for maximize protection.
For those far away targets and hard-to-reach areas, EXAIR offers aluminum extension pipes to attach to the VariBlast Safety Air Guns. They can range from 6” (15 cm) to 72” (183 cm) in length. This light-weight and durable material allows for easy handling when reaching high above your head or spanning across unsafe areas. With the EXAIR air nozzles at the end, the blowing force is not sacrificed as the back pressure will create a high velocity air stream.
To get the proper amount of compressed air from the piping system to the VariBlast Safety Air Guns, EXAIR offers Coiled Hoses. They are made of a durable abrasion-resistant nylon material that is 12 feet long (3.6 meters). They have swivel fittings to allow for easy uncoiling, and a spring strain relief to keep the hose from kinking at the ends. The coiled design makes it easy to reach around the work area and retract back to the substation. This will help to keep the hose off the ground where potential dangers could occur.
To improve the use of the VariBlast Safety Air Guns, EXAIR offers a series of filters and regulators. The Filter Separators will remove dirty particles and liquid water from the compressed air that can affect the performance as well as contaminate the surface that you are cleaning. The Regulators are used to control the amount of air pressure used by the VariBlast Safety Air Gun; making them even more efficient. The idea for compressed air savings is to use the least amount of compressed air to do the job. The combination of a filter and regulator will allow you to control the proper amount of clean dry air to be used.
Not all air guns are the same. There should be a check list created prior to purchasing an air gun. Is it safe, efficient, quiet, durable, ergonomic, and flexible? The VariBlast Safety Air Guns meet every item on that list. This is why the EXAIR VariBlast Safety Air Gun was awarded the Silver award by Plant Engineering. If your current air gun does not meet these requirements, you may want to try the VariBlast Safety Air Gun. You will not be disappointed. If you are within the U.S. or Canada, we do offer a 30-day unconditional guarantee to try them out.
A critical component on the supply side of your compressor system is the dryer. Atmospheric air contained within a compressed air system contains water vapor. The higher the temperature of the air, the more volume of moisture that air is capable of holding. As air is cooled, this water vapor can no longer be contained and this water falls out in the form of condensation. The temperature where this water will drop out is referred to as the dew point.
At a temperature of 75°F and 75% relative humidity, approximately 20 gallons of water will enter a 25HP compressor during a 24-hour period. As air is compressed, this water becomes concentrated. Since it’s heated during the compression process, this water stays in a vapor form. When this air cools further downstream, this vapor condenses into droplet form.
Moisture within the compressed air system can result in rust forming on the inside of the distribution piping, process failure due to clogged frozen lines in colder weather, false readings from instruments and controls, as well as issues with the point of use products installed within the system.
In a membrane dryer, compressed air is forced through a specially designed membrane that permits water vapor to pass through faster than the air. The water vapor is then purged along with a small amount of air while the rest of the compressed air passes through downstream. Generally, the dew point after the membrane dryer is reduced to about 40°F with even lower dew points also possible down to as low as -40°F!
With such low dew points possible, it makes a membrane dryer an optimal choice in outdoor applications that are susceptible to frost in colder climates. Membrane dryers also are able to be used in medical and dental applications where consistent reliability is critical.
A membrane dryer does not require a source of electricity in order to operate. The compact size makes it simple to install without requiring a lot of downtime and floor space. Since they have no moving parts, maintenance needed is minimal. Most often, this maintenance takes the form of checking/replacing filter elements just upstream of the membrane dryer. The membrane itself does need to be periodically replaced, an indicator on the membrane dryer will display when it needs to be changed. If particular instruments or processes in your facility are sensitive to moisture, a membrane dryer might be the best option.
However, there are some drawbacks to these types of dryers. They’re limited to low capacity installations, with models ranging from less than 1 SCFM up to 200 SCFM. This makes them more applicable for point-of-use installations than for an entire compressed air system. The nature in which the membrane dryer works necessitates some of the air to be purged out of the system along with the moisture. To achieve dew points as low as -40°F, this can equate to as much as 20% of the total airflow. When proper filtration isn’t installed upstream, oils and lubricants can ruin the dryer membrane and require premature replacement.
Make sure and ask plenty of questions of your compressor supplier during installation and maintenance of your system so you’re aware of the options out there. You’ll of course want to make sure that you’re using this air efficiently. For that, EXAIR’swide range of engineered Intelligent Compressed Air Products fit the bill. With a variety of products available for same-day shipment from stock, we’ve got you covered.