Digital Flow Meters Prevent Rework by Measuring Air Flow to a Paint Gun

EXAIR Digital Flowmeter

EXAIR Digital Flow Meters are used to measure compressed air use throughout a facility, and they can also provide preventive measurements for critical processes.

A customer of ours had a paint booth that was used to touch-up large metal panels.  Inside that paint booth, they had two, High Volume Low Pressure (HVLP) paint spray guns.  These paint guns work well as they limit the air pressure to the air cap to reduce overspray and bounce back.  With the lower air pressure, the paint can have a tendency to dry and block a portion of the nozzle.  This can affect the atomization and the lay down of the paint.  To overcome this, operators have a tendency to increase the air pressure which can create other issues in spraying, as well as using excessive paint.  They decided to install some compressed air flow meters in their compressed air lines to monitor their paint system, and with the idea to prevent quality of spray problems before they occur.  They contacted EXAIR to get a better understanding on what we can offer.

In discussing their system, I learned they had an enclosed semi-downdraft spray booth.  They had two runs of ½” NPT Schedule 40 compressed air lines that came from the mainline above.  Both compressed air lines were positioned outside the booth in the left and right back corner.  (Each HVLP spray gun had its own compressed air supply).  The compressed air pipes ran down along the wall with standoffs in the back area.  From there, it elbowed into a filtration system then into the spray booth.  The customer mentioned that he did not have much room between the wall and the spray booth.  The booth had windows located in the door about 20 feet away.  As for their HVLP spray guns, they were set up to operate at 15 SCFM and 30 PSIG.  Depending on how often the spray guns were used during the operation, the paint had a tendency to dry and start to cause blockage.  Before the operator knew it, the paint gun started to become inconsistent, causing blemishes.  They would then have to rework the panel which was costly, affecting profitability.

The EXAIR Digital Flowmeters are designed to measure flow continuously and accurately.  You do not need to weld, cut, or disassemble pipe lines to install.  With a drill guide, the Digital Flowmeter can be easily mounted onto the pipe.  They did not need to unscrew filters, piping, etc. to install these in the back corners of the spray booth.  They just had to drill two small holes, insert the two probes into the holes, and tighten the clamp.  I recommended the model 9090 1/2″ Digital Flow meter.  It has a flow range from 0 to 90 SCFM which was perfect to monitor the HVLP spray guns.  The Digital Flowmeter measures flow by comparative analysis with thermal dispersion; so, the accuracy is very high and recalibration is not required.

Summing Remote Display

Since the Digital Flowmeter was located in the back corner, we needed to get a display over to the viewing window for the operators.  As an option, EXAIR offers a Summing Remote Display, model 9150.  This display has large LED numbers that can remotely displaying the flow from the Digital Flowmeter up to 50 feet away.  They installed the Summing Remote Display and mounted it outside the viewing windows of the spray booth.  The operator could now monitor the flow of the compressed air in real time with just a glance.  Now, when they were spraying paint, they could tell when the flow was starting to decrease.  They could stop and make the necessary changes to the nozzles, reducing the need to rework product.

Being able to measure the unknowns in your compressed air system as a prevention tool, it becomes much easier to evaluate, correct, and discover issues that may occur before they get out of hand.   The EXAIR Digital Flowmeters can give you the real-time flow measurements of your compressed air system to help identify problems.

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

Troubleshooting Vortex Tube Performance

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This Vortex Tube was not operating properly when initially connected to compressed air

One of the fun parts of Application Engineering at EXAIR is explaining the operation of Vortex Tubes to our customers.  Sometimes they’re described as a “reverse tornado” inside of a tube, spinning a pressurized airstream and converting it into a hot and cold flow.  Other times we describe it through the generation of two vortices with differing diameters, and the difference in diameters results in one vortex shedding energy in the form of heat.

But, no matter the way we explain their operation, we always stress the importance of proper compressed air plumbing.  If the compressed air piping/hoses/connections are not properly sized, performance problems can arise.  (This is true for any compressed air driven device.)

This fundamental came to light when working with one of our customers recently.  They were using a medium sized Vortex Tube to provide spot cooling in an enclosed space, but were not seeing the flow and temperature drop they knew to be possible with an EXAIR Vortex Tube.  And, after looking at installation photos of the application, the root cause was quickly spotted.

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The red arrow in the bottom right corner of this image shows the beginnings of a reduction in compressed air supply.

I noticed what looked to be a very small hose connected to the inlet of the Vortex Tube in the image above.

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In this additional image, the small compressed air line is in full view. This was the root cause for performance problems in this application.

After further inspection of another photo, the small diameter tube was in full view.  This small hose serves as a restriction to compressed air flow, which in turn limits both flow and operating pressure of the downstream devices.  What that meant for this application, was poor performance from the Vortex Tube, all stemming from this reduction in piping size.

When looking to find the root cause of a performance issue with a compressed air driven unit, things aren’t always as easy as they were with this application.  A visual inspection is always a good idea, but if everything looks correct, here is a list of troubleshooting steps to consider:

  1. Check for quick-disconnects in the plumbing system.  Quick-disconnects are great from an operator’s perspective, but they can wreak havoc on compressed air flows due to small inside diameters and air volume restriction.
  2. Determine the operating pressure at the device.  This is imperative.  In order to make proper decisions to correct the performance concern, good information is required.  Knowing what is happening at the device is crucial for proper understanding.  There may be 100 PSIG at the main compressed air line, but only 60 PSIG at the device due to plumbing problems. A pressure gauge at the inlet of the compressed air product can provide this information.
  3. Check that the compressed air system has enough volume to properly supply the device.  A compressed air driven unit without the correct volume of compressed air is just as bad as having a lack of pressure.
  4. Check for leaks.  The US Department of Energy estimates that 20-30% of compressor output in industrial facilities is lost as leaks.  If your system and devices aren’t operating as they’re supposed to, check for leaks.  They may be contributing to the poor performance.  (Don’t know where your leaks are coming from?  Use our Ultrasonic Leak Detector!)

Fortunately for this customer, after improving the size of this tubing performance was on par with our published specifications and this customer was back in operation.  If you have a question about how to improve the utilization of the compressed air devices in your application, contact an EXAIR Application Engineer.

Lee Evans
Application Engineer
LeeEvans@EXAIR.com
@EXAIR_LE

EXAIR Super Air Knives Can Make Everything Better…Even Popcorn!

You know the drill.  In almost any container of popcorn…whether it’s a movie theater bucket, a microwave bag, a stovetop pan (if you’re old school,) or a campfire popper (if you camp with class)…there’s always going to be some un-popped kernels.  And if you don’t pay particular attention to them, they might just activate your dental plan.

This is, unfortunately, an unavoidable inconvenience when dealing with freshly popped popcorn.  For a company that makes pre-packaged popcorn-based snacks, though, un-popped kernels are a real quality issue.  I just had the pleasure of helping a caller with this very issue: although they had a sifter device in place that took care of an awful lot of un-popped kernels, they still had enough getting through to merit a closer look.  Since the popcorn already passed through the sifter on a conveyor, the idea was to “float” the popped kernels across a short break in the conveyor, and let the un-popped kernels fall through.

After a short discussion of their needs, I recommended a Model 110224 24″ Aluminum Super Air Knife Kit. By using the Pressure Regulator (included with the kit) to dial in the air flow, they’re able to keep the popped deliciousness moving on for packaging, and let the dental hazards to fall through, where they’re sent back for another attempt at proper popping. So, they’re not only improving the quality of their product, they’re doing everything possible to make sure no kernel goes un-popped.

Super Air Knife Kits include a Shim Set, Filter Separator, and Pressure Regulator…everything you need to solve your application!

At EXAIR, we’re all about safety when it comes to compressed air use in industrial and commercial settings.  Now one of our products is helping protect peoples’ teeth while they’re eating popcorn snacks!  If you’d like to talk about how an EXAIR Intelligent Compressed Air Product might be able to make things better for you, give me a call.

Russ Bowman
Application Engineer
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Daylight Savings Time = Spring Is Coming!

This coming Saturday, 3/12/17, the U.S. will observe Daylight Savings Time, commonly referred to as “spring forward and fall back” here in the eastern states. On the second Sunday in March at 2:00 AM, we “spring” our clocks forward 1 hour to 3:00 AM and this lasts through November when we then “fall” back from 2:00 AM to 1:00 AM. The goal of the practice is to provide more daylight through the evening hours of the spring and summer months.

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Don’t be “alarmed”, warmer temps are coming!

For me personally, it means one less hour of sleep and now my 8 year old son tries to reason with me on why he can stay outside and play longer now on school nights. YAY! The time change also reminds us that Spring is almost here but really we can’t complain too much here in Cincinnati, OH as we have had a fairly mild winter to say the least. With the warmer temperatures coming and the extra hour of daylight, it’s time to start the proverbial “spring cleaning” around the house and yard. And trust me, with an active 8 year old and a soon-to-be 2 year old, I have more than enough maintenance items to keep myself busy.

Here at EXAIR, we understand the importance of keeping industrial areas clean and tidy to maintain steady production as well. Our full line of compressed air operated Industrial Housekeeping Products provide a fast, reliable and virtually maintenance free way to keep critical processes flowing smoothly. Take for example our Reversible and High Lift Reversible Drum Vacs, used to vacuum spent coolant or other liquids and deposit them to a standard closed head steel drum. Or our Chip Trapper or High Lift Chip Trapper, which filter out suspended solids in liquids and captures them in a reusable filter bag inside the drum. With the simple turn of a knob, all of these units can be “reversed” to a powerful pump, to empty the drum to another reservoir or collection device. For dry material handling we offer our Chip Vac system or for more abrasive dry material, like steel shot, the Heavy Duty Dry Vac. When it comes to dusty areas, we offer our Heavy Duty HEPA Vac, providing HEPA filtration or 99.97% at 0.3 micron. ALL of these products are available in 30, 55 or 110 gallon systems.

From now through May 31, 2017, by ordering one of the above systems, we’ll include a FREE Vac-u-Gun with your purchase. You will need to order using the special promo code.

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Click for promotional Model # for ordering

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

Silhouette of an Alarm Clock image courtesy of zeevveez via Creative Commons license.

 

 

New! In Stock! Sanitary Flange 316 Stainless Steel Line Vacs

Just released, we are now stocking four different pipe sizes of Sanitary Flange 316 Stainless Steel Line Vacs. We are offering these in the following sizes, 1-1/2″, 2″, 2-1/2″, and 3″ Sanitary Flange.   The performance is the same as our Stainless Steel Line Vacs,  but now it is even easier to install in sanitary flanged piping systems.  No need to get adapters or have specialty shops weld flanges on.

Model 161200-316 - 316 Stainless Steel Sanitary Flange Line Vac

Model 161200-316 – 316 Stainless Steel Sanitary Flange Line Vac

The new Line Vacs are available for purchase on their own or in a kit which includes the Line Vac, a mounting bracket for the Line Vac, pressure regulator and filter separator. The only parts you provide are the clamps, gaskets and compressed air supply.

With a wide range of sizes and materials of construction, we've got your solution. Call us.

With a wide range of sizes and materials of construction, we’ve got your solution. Call us.

These are the latest four additions to our already extensive line of in-line pneumatic conveyors.   If we do not offer a stock Line Vac that will fit your needs, we also offer custom Line Vacs to fit virtually any need you may have, just contact us and we will help you determine what will work!

Custom PVDF Line Vac

Custom PVDF Line Vac

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

Super Air Knives Used as a Non-Contact Barrier in a Non-Woven Application

An overseas customer manufactures a 2.2 meter wide non-woven material.  In one of their processes, the media would travel through a spray booth to apply a water-based surfactant.  The surfactant was atomized and blown onto the top and bottom of the material.  The spray booth was equipped with a fume hood to capture any excess mist.  The material would then travel out of the spray booth and into the oven to dry.

Area between Spray Booth and Oven

Area between Spray Booth and Oven

Because they were running at a speed of 160 m/min, a draft was being created as the media was exiting the spray booth.  This draft was strong enough to overcome the vacuum pressure from the fume collection system.  This would allow the excess mist to escape the spray booth.  It was then collecting on the surface of the oven and floor outside the containment area.  This created a safety issue as well as a large mess.

In looking at the problem area, the dimension of the opening of the spray booth was 2.65 meters by 300 mm.  To blow a good curtain of air to contain the mist, we needed to have a laminar flow to create that “wall”.  I recommended two pieces of a model 1102108 Super Air Knife Kits.  At 108” (or 2.74m) long, they are the longest Super Air Knives in the market.  With a steady flow of air along the entire 2.74 meter length, it can generate that curtain of air across the entire opening of the spray booth.  The laminar flow was key as they did not want to disturb the spraying nozzles inside the booth.

The Super Air Knife Kit also comes with a filter, a regulator, and a shim set.  With the included shim set, the force can be changed dramatically by using a different thickness of shim.  Since they did not need much force to keep the mist inside the spray booth, they opted to put a thinner shim inside the Super Air Knife.  This would reduce the amount of compressed air needed, and with a regulator, the customer could “dial” in the correct amount of force to create the proper air barrier.  The Super Air Knives were mounted above and below the material to blow directly across the opening of the spray booth.  Any fine mist that would come in contact with the air would be deflected back into the spray booth.  With the extra mist removed from the process, the fume extraction system could then perform its duties the way it was intended. With air being used to create that barrier, it did not disrupt the structure of the material or the surfactant on its surface.

Super Air Knife

Super Air Knife

If you require a non-contact barrier for your application, EXAIR Super Air Knives could be your solution.  For this customer, we were able keep the work place safe and mess-free.

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

Offshore Pipe Welding Cooled with Series of EXAIR Super Air Nozzles

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EXAIR model 1122 Flat Super Air Nozzles used to provide cooling blow off.

One of the services we provide to our customers, is assistance in selection of the most suitable product solution for their application.  For most applications we have solutions readily available from stock, though that wasn’t the case in the solution shown above.

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This unique blow off solution cools welds on 450mm (18″) pipes.

This configuration of model 1122 Flat Super Air Nozzles is used to cool pipe welds in an application located off the coast of France.  Pipes with an OD of 450mm (~18”) are welded together, and in order for the welds to be of the highest quality, they must be cooled.  To cool the welds, this customer needed to blow ambient temperature air over the pipes.

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Closeup of nozzles used in this application

Initially, we explored a Super Air Wipe solution.  A Super Air Wipe can provide a full 360° blow off for this pipe, but there was an aspect of the application which led to a better solution through nozzles; an irregularity in position of the pipe.

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Another view of the 1122 Flat Super Air Nozzles

The diameter of the pipes in this application is relatively constant, but there is some fluctuation in position as the pipe is moved.  If using a Super Air Wipe, this could mean contact with a precision machined surface, resulting in a change to the performance of the unit.  But, what if we could find a way to allow the blow off solution to have some “flex”.

swivels

Flat Super Air Nozzles with swivels provide the unique solution needed for this application.

“Flex” in this solution is provided through the use of EXAIR model 9053 swivel fittings, shown above with red circles, each used to mount an 1122 Flat Super Air Nozzle (16 of each).  These allow for proper placement of the nozzles, and also for movement if anything should ever contact the blow off solution.

An additional benefit of the EXAIR 1122 nozzles used in this application, is the ability to exchange shims inside the nozzle to increase or decrease the amount of force delivered from the nozzle.

Understanding the critical requirements of the customer led to this semi-custom solution using EXAIR Super Air Nozzles.  If you‘d like to explore an EXAIR blow off solution for your application, contact an EXAIR Application Engineer.

Lee Evans
Application Engineer
LeeEvans@EXAIR.com
@EXAIR_LE

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