Tag: SCFM

One Item Generates 1/4 Ton of Refrigeration and Fits in the Palm of your Hand

Published on by Dave WoernerLeave a comment

One of the most powerful, peculiar and perplexing products in the EXAIR catalog is the Vortex Tube. The medium sized vortex tube can generate up to a ¼ ton of refrigeration and still fit into the palm of your hand. It can generate cold temperatures that are 129° Fahrenheit below the input compressed air temperature, without any moving parts. It provides effective cooling on a wide variety of industrial systems like electrical cabinets, cutting tools, grinding operations, setting hot melt glue and a number of other cooling processes.

The Vortex Tube is used in Cabinet Cooler Systems, Cold Guns, Mini Coolers and Adjustable Spot Coolers to utilize compressed air to create cold air for your application needs. The Vortex Tube uses a Ranque-Hilsch tube to create the cooling effect. This principle has been used since 1927 to generate hot and cold flows from a source of compressed air. For more information on the physics behind how the Vortex Tube operates, visit here.

Our units are designed to operate at inlet pressures between 20-120 PSIG. The vortex tube comes in three different sizes, small, medium and large. The small unit will use between 2 and 8 SCFM of compressed air when fed with 100 PSIG of compressed air. It can be used with pressures much lower, but the change in temperature will not be as great. Below is a chart listing the temperature drops and rises of the vortex tubes with respect to supply pressure and cold fraction.

Vortex Tube Performance Data
The Cold Fraction performance chart shows temperature drops and rises for a Vortex Tube.

To use Vortex Tubes intelligently, cold fraction needs to be defined. A cold fraction is the ratio of cold air flow to total air flow through the inlet of the Vortex Tube. This cold fraction is adjustable on the Vortex Tubes and Adjustable Spot Coolers, but it is preset on the Cabinet Cooler Systems and Cold Guns. Adjusting the cold fraction changes 2 variables with the Vortex Tube. First, it changes the amount of cold flow from the Vortex Tube. Second, lowering the cold fraction also lowers the cold air temperature. Flow and temperature will both determine the heat transfer of the system.  For tool cooling operations, a very high cold fraction is used.  If you have a tool that may be operating above 150 or 200° Fahrenheit, it will cool faster with more air flow at a higher temperature than air at sub-zero temperatures. For applications where the final temperatures are very low, below freezing or sub zero, lower cold fractions can be used.

Find the blog next week to find out about what the addition of generators affects on a Vortex Tube.

Dave Woerner
Application Engineer
DaveWoerner@EXAIR.com
@EXAIR_DW

3 Common Mistakes in Your Compressed Air System

Published on by Dave WoernerLeave a comment

Every day I speak with engineers who are having trouble using compressed air products. A common problem they have is not providing an adequate air supply to their unit. I go through a basic troubleshooting technique to ensure that their pressure and flow rate is adequate. I ask them to install tee on the inlet to the compressed air product in order to install a pressure gauge right at the inlet to the pipe. This allows us to know exactly what pressure we are supplying to the product. Customers are always surprised how the gauge on the compressor or the regulator may read 120 PSIG, but the gage on the inlet to the compressed air product is significantly less.

Last year, my colleague, Russell Bowman, made an excellent video showing how the inlet pressure at the knife will have a significant impact on the performance of the Super Air Knife.  In the video, he changes the length and ID of the compressed air supply to illustrate the difference a proper supply line will have on the performance of a compressed air products.

Not providing adequate air supply is commonly caused by these three mistakes, when plumbing compressed air systems.

1. Incorrectly Sized Piping – This can be the single biggest problem. A lack of planning before installing a compressed air product. Not all compressed air systems are created equal. Though a 1/4″ shop air hose may work for a number our products, some of our products require a larger air line because they require more volume of air to be effective. We often speak with customers an illustrate this problem by stating small air lines are like trying to feed a fire hose with a garden hose – there simply is not enough volume to create the pressure necessary to reach the fire, or solve the application in our scenarios. We publish the flow rates for all of our products and make inlet pipe size recommendation in the installation and maintenance guide furnish with the products so you may avoid this common problem. We also have air data tables in our Knowledge Base or  you may consult an application engineer who will be happy to make the proper recommendation.

2. Quick Disconnects – These handy connectors are great when operating a brad nailer, or a small blow gun, but the small through diameter can severely limit the flow rate into a long air knife, large diameter air operated conveyor, or big vortex tubes.  Due to this fact it is strongly advised to use threaded fittings or over-sized quick disconnects.

3. Adding extra hose or pipe – Extra hose is never a bad thing, right? No, an extra 30 feet of air hose can significantly drop the pressure of a compressed air system. 20 feet of ½ Pipe can flow 70 CFM with a 5 PSI pressure drop.  50 feet of ½” pipe will only flow 42 SCFM with the same 5 PSIG pressure drop. Keep your hose or pipe lengths to a minimum to improve the volume of air you can deliver to a compressed air product.

Dave Woerner
Application Engineer
DaveWoerner@EXAIR.com
@EXAIR_DW

I Just Saved 15% Of My Compressed Air Usage In 15 Minutes

Published on by Brian FarnoLeave a comment

I’ve been pretty entertained over the past few weeks with all the new commercials from a certain insurance company that boasts their ability to save you 15% in 15 minutes.  Well sure enough one of their competitors has now flipped that on them and turned it into almost a joke.  Their competitor now claims to save the same amount in half the amount of time.  While they never say the name it is still making sure that you get the point they are better than their competition.

dirtysales

While the commercials are funny and I do get a kick out them it is still just talk until you actually try them out.   Here at EXAIR we have our own competitors who will claim their flow is one less SCFM than a similar EXAIR product, or maybe 1 dBA quieter.   The fact of the matter is, they can say whatever they want to in advertisements, catalogs, on websites, or even blogs.   What matters is the actual performance of the products as well as the level of service you receive from the company before and after you purchase.  We’ve said it before, and we will say it again, the proof is in the pudding.

EXAIR will not only provide you with enough (if not more than enough) information before you purchase a product, we will also then stand behind the product with a 30 day guarantee.  To top all of that off, we make ourselves available through phone, email, fax, mail, live chat, or even stop in our facility.  The point is we are here to help and we aren’t going to disappear after you buy the product.

Note: Depending upon your current SCFM use and total capacity – you may be able to save 15% by just twisting on some engineered air nozzles in place of open blow offs. This could actually be performed in less than 15 minutes – you get the picture…

Brian Farno
Application Engineer
BrianFarno@EXAIR.com
@EXAIR_BF

Compressed Air Calculations, Optimization, and Tips

Published on by Kirk EdwardsLeave a comment

EXAIR uses our blog platform to communicate everything from new product announcements to personal interests to safe and efficient use of compressed air. We have recently passed our 5 year anniversary of posting blogs (hard for us to believe) and I thought it appropriate to share a few of the entries which explain some more of the technical aspects of compressed air.

Here is a good blog explaining EXAIR’s 6 steps to optimization, a useful process for improving your compressed air efficiency:


One of the Above 6 steps is to provide secondary storage, a receiver tank, to eliminate pressure drops from high use intermittent applications. This blog entry addresses how to size a receiver tank properly:

Here are 5 things everyone should know about compressed air, including how to calculate the cost of compressed air:

These next few entries address a common issue we regularly assist customers with, compressed air plumbing:

In a recent blog post we discuss how to improve the efficiency of your point of use applications:

Thanks for supporting our blog over the past 5 years, we appreciate it. If you need any support with your sustainability or safety initiatives, or with your compressed air applications please contact us.  

Have a great day,
Kirk Edwards
@EXAIR_KE