Super Air Amplifier Increases Airflow In Vaccum Hood For Fume Extraction

A couple days ago I  took a call from an extrusion company who was looking to increase the airflow in their plating operation. They manufacture several different shapes and styles of aluminum extrusions by the way of 8 large extrusion presses. On one of the presses they make a specialty line of products that are sent to a finishing operation to be anodized.

Above the anodizing process tanks they use a vacuum hood to capture fumes and send them to a scrubber system so the air can be cleaned before being exhausted. They were starting to see an increase in the level of VOC (Volatile Organic Compound) gases in the area and, after some internal testing, determined the existing system wasn’t moving enough air through the system for the gases to be adequately delivered to the scrubber tank.

Example of a scrubber system

After further discussion, the customer ordered our Model # 120022 2″ Super Air Amplifier to test under our Unconditional 30 Day Guarantee.  Air Amplifiers are one of the most efficient products in the EXAIR catalog. Using a patented internal shim, they use a small amount of compressed air that passes through an internal chamber where it is exhausted through a thin gap at high velocity. This directed airflow creates a lower pressure at the intake side which draws in a large amount of free air. The 2 combining air flows result in a large volume of “amplified”, high velocity exhausting airflow, making them ideal for increased air movement.

Air Amplifiers entrain enormous amounts of “free” air, at ratios of up to 25:1!

If you have an application where you need to increase airflow or if you’re looking to vent or exhaust noxious fumes, an Air Amplifier is the ideal choice. For help selecting the best Model or to discuss a particular process, please contact an application engineer for assistance.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

 

Pueblo Chemical Agent-Destruction Pilot Plant Agent Processing Building courtesy of PEO ACWA via creative common license.

 

EXAIR’s Industry Leading Super Air Knife Saves You Money

One common application that we get calls for each and every day centers around maximizing compressed air efficiency. I recently got to work with a customer who was using an inefficient blowoff method and was looking to replace it with an engineered compressed air solution. They had a total of (8) extrusion lines, each with (3) modular-hose style flat nozzles installed. Before a cooling bath they had one nozzle remove some of the heat, then as the extruded material exits the water bath another (2) nozzles blowoff any residual water. They were maxing out their compressor’s peak operating capacity and pressure drops across the system were causing problems elsewhere in other processes.

KIMG0161

They were operating each of the flat nozzles at 50 psi using a total of 17 SCFM per nozzle. We first calculated how much air the current method was using. The extrusion lines were run for one full 8-hr shift per day:

17 SCFM/nozzle x 3 nozzles/line = 51 SCFM per extrusion line

51 SCFM x 60 mins x 8hrs x 5 days x 50 weeks = 6,126,000 SCF

The extrusion lines accommodated product that ranged from 1”-2.5” wide. They wanted one single solution to use across all different products. We settled on (3) of our 110003 3” Super Air Knives. Let’s take a look at the compressed air requirement for (3) 110003 Super Air Knives, also operated at 50 psig.

A Super Air Knife will consume 1.9 SCFM/inch when operated at 50 psig:

1.9 SCFM/inch x 3 inches (per knife) = 5.7 SCFM/knife

5.7 SCFM x (3) total knives = 17.1 SCFM

17.1 SCFM x 60 mins x 8hrs x 5 days x 50 weeks = 2,052,000 SCF

Total savings per extrusion line – 6,126,000 SCF – 2,052,000 SCF = 4,074,000 SCF

4,074,000 SCF x 8 extrusion lines = 32,592,000 SCF

By replacing the (3) inefficient nozzles with EXAIR’s Super Air Knives, a whopping 4,074,000 SCF of compressed air is saved each year. With (8) total lines, this equates to a total of 32,592,000 SCF of compressed air. Most companies will know the cost of their compressed air usage per CFM, but a cost of ($0.25/1000 standard cubic feet) is a good baseline to use.

($.25/1000 SCF) x 32,592,000 SCF = $8,148.00 USD

By replacing (3) inefficient nozzles across all (8) extrusion lines with EXAIR’s industry leading Super Air Knife, they were able to save a total of $8,148.00 per year. In as little as (6) months, the Super Air Knives will have already paid for themselves!!

If you’ve been maxing out your compressed air system, don’t necessarily assume you need to increase your overall capacity. Put in a call to an EXAIR Application Engineer and we can take a closer look at the ways your using your compressed air throughout the facility. By replacing some inefficient methods with an engineered solution, we can help you save air and money!

Tyler Daniel
Application Engineer
E-mail: TylerDaniel@exair.com
Twitter: @EXAIR_TD

Super Air Wipe Vs. Block Type Air Wipe

Air Wipes, which provide 360 degree blowoff, are typically used to remove heat, liquid, debris or static from wire, cable, pipe, tube, or extrusions.

We had a customer that was using a block type Air Wipe from a competitor to remove water from an extrusion.  These air wipes are built using a plastic material, typically with some additional ceramic insert to resist abrasion of the wire, the halves are hinged with air holes drilled into each half which carries air through the block and on to the wire. They were using these block air wipes on several lines. The interesting point of this blog is that it required 5 block type air wipes to equal the results of 1 EXAIR Super Air Wipe.

Since EXAIR’s Super Air Wipe equaled the performance of 5 of the competitors it consumed less air was less expensive and produced less noise.  Also in space sensitive applications the EXAIR Super Air Wipe is much thinner than the block type.  To highlight this the Super Air Wipe is 1.13″ thick on all 11 models that range from 3/8″ to 11″ throat diameter.   The performance of the block air wipe can only be changed by altering the inlet air pressure while the EXAIR Super Air Wipe can also be changed by adusting the inlet air pressure OR by adding an additional shim the force can be nearly doubled!

Many of these block type air wipes use a series of holes to direct the compressed air supply at an angle over the material that needs to be cleaned off.  EXAIR’s Super Air Wipe being an engineered compressed air product use’s fluid dynamic’s to create more force as demonstrated below. The air from EXAIR’s Super Air Wipes is a continuous 360 degrees, without the gaps a series of holes creates.

sawworksani
How The Air Wipe Works

Compressed air flows through the inlet (1) of the Air Wipe into the annular chamber (2).  It is then throttled through a small ring nozzle (3) at high velocity.  This primary airstream adheres to the Coanda profile (4), which directs down the angled surface of the Air Wipe.  A low pressure is created at the center (5) inducing a high volume flow of surrounding air into the primary airstream.  As the airflow leaves the wipe, it creates a conical 360° ring of air that attaches itself to the surface of the material running through it (6) uniformly wiping the entire surface with the high velocity airflow.

Block type air wipes are generally available in standard sizes up to 7″ in diameter while EXAIR’s Super Air Wipes are available in stock diameters up to 11″ and we also offer custom sizes to suit many other applications.

If you have any items that need to have a 360 degree blowing pattern, I would enjoy hearing from you…give me a call.

Steve Harrison
Application Engineer
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Proper Plumbing Means Proper Performance

36″ Aluminum Super Air Knife being used in a monofilament extrusion line

An EXAIR customer recently contacted me about the application shown above, using an aluminum Super Air Knife model 110036 as a component to a blow off application in a monofilament extrusion line.  The extrusions from this line are used in one of the end user’s main product lines, a personal health device used by over a billion people around the world.

The original problem of drying the extrusions can certainly be solved with the setup shown, but the output force from the knife was less than what the customer expected, and below the EXAIR published data.  We take great care in the collection and verification of our performance data, so this prompted a deeper dive into the application to determine what could be the cause.

Immediately upon seeing the application photos, there were two things which stood out.  The first was the angle of attack of the knife, and the second was the compressed air plumbing.  The angle of attack in the original setup was ~90°, nearly perpendicular to the extrusions passing through the airstream from the knife.  EXAIR always recommends an angle of attack of ~45° to increase time in contact between the airstream from the knife and the materials passing through the airstream.  Although a small adjustment, this angle significantly contributes to overall blow off performance.

5mm ID x 8mm OD tubing used to supply compressed air to the knife

But, the real issue with this application was in the compressed air supply.  The tubing for this knife was shown as having a 5mm ID and an 8mm OD, which will allow a compressed air flow of ~40 SCFM at 80 PSIG, maximum, without consideration to pipe length from the compressor.  The 36” aluminum Super Air Knife will require 104.4 SCFM at 80 PSIG operating pressure.  So, it was clear that there was a significant plumbing problem, leading to the reduced performance from the knife.

In order to prove this out, we first had to take a pressure reading directly at the knife.  When this was done, the operating pressure dropped from ~85 PSIG at the main header to less than 20 PSIG at the knife.  By taking this pressure reading directly at the knife we were able to gain valuable information as to the true operating pressure of the knife, which was far below what the customer expected, but which made perfect sense given the performance output.

The remedy in this case was to increase the size of the supply line to at least 15mm ID (approximately equivalent to a ½” schedule 40 line), and preferably to something in the range of 19-20mm (~a ¾” schedule 40 line).  Once this was done the knife operated flawlessly, and after adjusting the angle of attack this application was optimized for the best possible results.

Being able to find the source of the problem for this application was a great service to the customer.  Our engineers are well-versed in compressed air system requirements, and we’re available for help in your application if needed.  If you’d like to contact an EXAIR Application Engineer we can be reached by email, phone (1-800-903-9247), or Twitter.

Lee Evans
Application Engineer
LeeEvans@EXAIR.com
@EXAIR_LE