Month: January 2016

Analogies Are Like…

Published on by Russ BowmanLeave a comment

I came up with this title for this week’s blog the other day, and I can’t think of something to compare an analogy to, in the context I wish to discuss today.  Isn’t that ironic?

I’ve always had good luck with analogies…if I need to explain something to someone, being able to draw a comparison to a well-known or easy to picture scenario just comes easy to me. Someone smarter than me once said “if you can’t explain it simply, then you don’t understand it well enough,” and analogies have always served me well in that regard.

They are, in fact, a popular tool of the trade in EXAIR’s Application Engineering department. The most common example is, in fact, the topic of my blog today.

If a caller wants to use a Vortex Tube to cool something that’s very hot, we may recommend a Super Air Nozzle, Air Amplifier, or Air Knife instead. The long answer is that there are two variables to consider in a conductive/convective heat transfer application using fluid flow: flow rate, and temperature differential between the object and the medium (air in this case.) If the item is indeed very hot, then you already have a very high differential between the item’s surface temperature and the temperature of the air (ambient) that you’ll be blowing on it…and our Intelligent Compressed Air Products serve to increase the air flow rate, by entraining “free” air from the surrounding environment. If there’s a moment of silence when we get to that part of the explanation, we’ll compare it to when you blow a quick breath on a spoonful of very hot soup, which, although your breath isn’t cold at all, it still cools that soup down in a hurry. In comparison to the temperature of the very hot soup your breath is cold. Then we take their order, ship their Super Air Nozzle (or Air Amplifier or Air Knife) and everyone’s happy.

If you’d like to discuss a compressed air product application – or if you can help me solve the problem of this blog’s title with a rapt analogy – please let me know. Either way, I’ll be as happy as a kid in a candy store to hear from you.

Russ Bowman
Application Engineer
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3″ Super Air Knife & 1″ Flat Super Air Nozzle Solve Bearing Measurement Inaccuracies

Published on by exaircorpLeave a comment

A bearing manufacturer was having an issue effectively removing oil from a bearing race prior to a laser micrometer for gauging dimensional tolerances. The bearings are assembled, travel through a washer and then go through a centrifugal dryer. After the dryer, the bearings travel down a conveyor to the laser micrometer, where they are measured, laser marked, coated with rust preventive and boxed for shipment. The issue they were having is after the centrifugal dryer, they were still seeing small droplets of oil and contaminants settling on the outside diameter of the outer ring, causing the laser to take a faulty reading which would reject part.

Bearing
Example of a caged bearing.

I recommended the customer mount a 3″ Super Air Knife over the top of the conveyor and a 1″ Flat Super Air Nozzle mounted vertically on each side to allow the bearing to pass through a “tunnel” of high velocity air to remove the foreign matter. While this would solve the contamination issue on the O.D. of the bearing race, it raised another concern to the customer. The laser takes the reading through a small slot on the side of the conveyor, and with the particulate being airborne again, the customer was concerned they may see some contaminants work their way through the opening and settle on the laser lens. The opening is about 3/4″ so I recommended they install another 1″ Flat Super Air Nozzle to blow across the small opening, making a curtain of air to block any foreign matter from passing through the slot.

Super Air Knife
Super Air Knife – Available from 3″ up to 108″.

 

1126
1″ Flat Super Air Nozzle providing 1″ wide, high velocity airflow.

This is just one example of using multiple EXAIR products to solve a single issue. Whether it’s a contamination blowoff application or something entirely different like cooling, exhausting fumes or conveying product, chances are EXAIR has a solution. Give us a call to see how we might be able to improve your process.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

 

DSCF4992 image courtesy of Joe Loong via Creative Commons license.

Cooling Fabric with a Super Air Knife Increases Production Speed

Published on by John BallLeave a comment
Super Air Knife has 40:1 Amplification Ratio
Super Air Knife has 40:1 Amplification Ratio

I received a call from a customer in the textile industry. The customer was producing a fabric that ends up being used for furniture.  The fabric varied in width between 4 feet (1.2 meters) and 6 feet (1.8 meters) wide.  In one of the processes, the material went through an oven to be heated to 200 deg. F (93 deg. C).  This would “set” a fire retarding chemical compound in the fabric.  As the fabric web exited the oven, they needed to cool it to roughly 120 deg. F (49 deg. C) so it could be handled by the operators.

The customer tried their luck at designing a duct that was seven feet (2.1 meter) long by one foot wide (30.5 cm) by one foot tall (30.5 cm).  At the bottom of the duct, they cut one inch wide (2.5 cm) slots along the length in an attempt to create a wide airflow across their material.  The large metal box (ducting) was suspended across the fabric and oriented to blow air straight down onto the material.  On the open end of the metal box, they mounted a fan to blow air inside with the intention that the slits in the duct work would direct the air from the fan onto the fabric.

Their idea worked to some small degree, but the cooling results were simply too little to continue with this kind of solution. Fortunately, the customer knew about EXAIR Corporation and they contacted us to see if we could help. Because they needed to provide additional time for the fabric to cool, they slowed their line speeds down to 20 yards/min (18 meters/min). It was obvious that they wanted to increase the throughput if they could.

In order to increase throughput, we needed to figure a way to increase the cooling rate.  To increase the cooling rate, we can either use colder air or more air.  Given the wide format of the material, the best decision for this application would be to blow more air across the target material.  The Super Air Knife has a 40:1 amplification ratio.  For every 1 part of compressed air, it will entrain and move 40 parts of ambient air to the target surface.  The result is that a larger volume of air hitting the surface of the material.  More volume hitting the target means we can cool it quicker.  I suggested a model 110272, 72″ Super Air Knife Kit to span across the different width of fabrics.  It can be mounted across the width of the material and set at a 45 degree angle to the material in a counter flow orientation. The reason for the angle and the counter-flow orientation are to enhance the cooling effect provided by the Super Air Knife. Orienting the Super Air Knife at a low angle allows for the flow coming from it to stay in contact with the material web for a much longer period of time.

By removing the fan with the duct work and installing the Super Air Knife, they found they could increase throughput to 30 yards / min. (9.2 meters / min). A 50% increase. The customer was thrilled about the significant increase as this was a real bottleneck in their production process.

If you have any cooling issues, you can rely on EXAIR to determine the best product. If you have any questions or would like to discuss any of your applications, you can contact the Application Engineers at EXAIR.

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

EXAIR Leads the Way with Product Standards

Published on by Brian FarnoLeave a comment

Standards seem to continually get introduced and updated. There is an ever increasing number of local, regional, federal, and even global standards to comply with.  We pay close attention to these standards and have the largest number of standards upon our products.

meets or exceeds oshaThe standards the every EXAIR product meets or exceeds are the OSHA standards for dead-end pressure as well as allowable noise level exposure.  The dead-end pressure directive is OSHA standard 29 CFR 1910.242 (b).  The standard refers to the fact that compressed air can be dangerous when the outlet pressure of a hole, hose or copper tube is higher than 30 psig (2 BAR).  In the event the opening is blocked by a hand or other body part, air may enter the bloodstream through the skin, resulting in a serious injury.  All of the compressed air products manufactured by EXAIR have been designed for safety.  All are safe to be supplied with higher pressure than 30 psig and still meet or exceed the OSHA standard.

The OSHA standard 29 CFR – 191.95 (a) refers to the maximum allowable noise exposure that an operator is permitted to be exposed to for a given period of time.   The chart of allowable exposure times is shown below.   All EXAIR products are engineered to create the minimum amount of noise while efficiently utilizing compressed air.   Many times blow offs are cross drilled to permit air to escape in order to meet the OSHA standard for dead end pressure, this process increases the noise level generated by that blow off considerably.

OSHA Noise Level

One of the most stringent compliance that EXAIR has upon its products is the UL/CUL listings and recognition.  All EXAIR Cabinet Cooler Systems are UL listed, we were the first to insure your electrical cabinet’s NEMA integrity remained by putting our Cabinet Cooler systems to the UL test. This means that the Underwriters Laboratories have deemed these products safe for operation throughout the US and Canada per their standards that are applicable for each of the product groups.   The products undergo numerous tests and scenarios to ensure that an operator will be safe during the normal operation of the units.   The tests for the Cabinet Cooler Systems includes environmental exposure for the given NEMA type of the enclosure along with many other tests.  The Static Eliminator Power Supplies are also UL listed.

cULlistedcULrecognized

CE is another standard which EXAIR pays great attention to to meet or exceed. CE is a standard that is normally preferred when dealing with countries outside of the US but is gaining popularity within the states as well.  CE being a European standard actually stands for a french phrase, “Confrmité Eurpéene” which is translated to “European Conformity”.  Any EXAIR product displaying the CE mark conforms where there are applicable directives.CE

The RoHS directive is targeted on heavy metals that are generally found within electronics.  Substances like Mercury, Lead, Polybrominated biphenyls, Cadmium, or Hexavalent chromium.  In order to meet the RoHs directive a product must have 100 parts per million or less of mercury and for other substances there must be less than 0.01% of the substance by weight in a raw homogeneous materials level. All EXAIR products which are electronic or contain electronic devices are compliant to the 2002/95/EC RoHS directive, also including the amendment outlined in the European Commission decision L 214/65.  This includes all EXAIR Static Eliminators, Electronic Flow Control, and Electronic Temperature Control products.ROHS_Vector

EXAIR maintains records to be sure our supply chain is providing product which meets the conflict mineral free guidelines of the Dodd-Frank Act.  EXAIR supports Section 1502 of the Dodd-Frank Wall Street Reform and Consumer Protection Act and we are committed to compliance with the conflict minerals rule in order to curb the illicit trade of tin, tantalum, tungsten and gold in the DRC region. EXAIR is using the CMRT 3.02 template to document our supply chain and commitment to conflict free products. When requested we will even provide the needed forms to support our customer’s efforts in complying with the Dodd-Frank Act.

conflictfree

REACH, is another European Community Regulation this time on chemicals and their safe use.  REACH is targeted to ensure personnel and environmental health by identifying the intrinsic properties of chemical substances easily.  REACH stands for Registration, Evaluation, Authorization and Restriction of Chemical substances and was written into law in 2007. EXAIR products are not required to be registered per Title II, Article 7, paragraph 1  of the legislation since they do not contain substances that are intentionally released.   This is to ensure compliance with Regulation (EC) No 1907/2006 Title I, Article 3, paragraph 3, the European Union requires registration of chemicals and substances imported into the EU to ensure a high level of protection of human health and environment.

Reach

 

To conclude, when there is a safety audit, safe sourcing directive or some other form of standard/conformance that you need to meet, consider EXAIR compressed air products. Please contact us to find out if we can help you meet or exceed those standards.

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