Cold Gun Eliminates Bottleneck in Press-fitting Application

A well known manufacturer of household appliance products contacted me recently with a cooling problem. Customer had a small, aluminum pulley that was heated and subsequently had a shaft pressed into it. The pulley weighed .07 lbs.  After the shaft press, the customer needed to cool from 500F down to 110F in 15 seconds or less. Current time was at 45 seconds with normal, compressed air exiting smashed pipe.

Customer implemented the Model 5330 High Power Cold Gun and was able to reduce cooling time to 15 seconds, realizing a 2/3 gain in time for the application.

Spot heating appliances using either gas or induction type heaters are quite common in industry. Spot Cooling options are extremely limited though. So, the High Power Cold Gun provides one solution for this kind of cooling application.

Neal Raker
Application Engineer
nealraker@exair.com

Line Vac vs Air Amplifier

Which one should you use?  That depends on your application.  At first glance they seem to operate in a similar manner.  But when it comes down to it, one really is better suited than the other, depending on the task it is being asked to perform.

I spoke to a customer last week who was currently using a 1″ Line Vac to transfer pieces of very small OD water drip tubing.  He was looking for a way to increase the efficiency of his application, namely decreasing his air consumption while still achieving the same transfer results.  His suggestion was to move to an Air Amplifier of similar size, since it has higher air amplification than a similarly sized Line Vac.  He mistakenly took this to also imply higher velocity, which is not actually correct. 

For moving a material that has any considerable mass to it, i.e. anything heavier than air or steam, a Line Vac is nearly always the best option.  While a Line Vac does have a much smaller air amplification ratio than an Air Amplifier, it also has a much higher vacuum level.  Thus, it is better able to pull solid materials through than an Air Amplifier would be.  It can lift the weight and transfer it over the required distance using a ring of directed nozzles to push the material through. 

An Air Amplifier is much better at moving large volumes of air in a short time frame.  It is able to quickly entrain the surrounding air and move it through the unit away from the vacuum area.  While it is able to move a large volume of air, it would not have the same capacity if moving a material of any considerable mass.  It creates its vacuum by using a Coanda profile on the ID of the unit.  The Coanda profile helps to accelerate the inlet compressed air which enters the unit through a small ring nozzle.  This acceleration is what entrains the ambient air from the rear of the unit, and the combined airflow is then directed towards the outlet of the unit. 

Based on the above comaprison, for this customer’s particular request, I suggested he stay with a Line Vac and just move to a smaller size.  The small tubing would still fit very well through the ID of a 1/2″ unit, so I recommended a model 6079 Stainless Steel model.  This will cut his air consumption approx in half, yet still easily be able to convey the light tubing material over the required distance. 

Emily Mortimer
Application Engineer
emilymortimer@exair.com

The Speed of Industry

A nuclear engineer I spoke with this morning said he graduated in 1966 and was obsolete in 1971, the technology in that industry was developing so fast that his knowledge was no longer useful. It seems as time goes on industry moves faster every day.

The compressed air industry is no exception, it is moving forward quickly with efficient technologies and safer products. A sharper focus on energy savings across the world naturally affects the industry. The globalization of industry expands markets. And the electronic age effects how products find their way into those markets.

At EXAIR we have embraced the speed at which things change. We have always had air nozzles but in 2002 EXAIR began development of our Super Air Nozzle line which greatly increased efficiency and lowered noise levels. We introduced the line with one model number 1100, and today offer no less than 38 models of Super Air Nozzles with similar characteristics. Since 2005 we have added over 1000 new model numbers.

In 2007 we added a completely new product line of Optimization Products, to keep up with the demand for compressed air efficiency. In 2008 another new product line was introduced, our E-Vac vacuum generators and we have added a new adjustable vacuum generator earlier this year. These new product lines increase our market and give EXAIR the ability to solve more problems for customers.

It seems like the quickest changes come from the way we try to communicate with customers, this blog is a good example and RSS feeds. We have posted videosof many products online. And my e-mail signature now has our Twitter link.

It’s a fast paced world out there. EXAIR is fully staffed and we have the knowledge to help you stay up to speed whether by saving some compressed air in your plant or helping a plant operation work better and/or faster or getting you some information quickly. Our Intelligent Compressed Air products are keeping pace with the speed of industry.

Kirk Edwards
Application Engineer
kirkedwards@exair.com

Scum Sucker

One of my customers needed a way to remove foam scum off the surface of a liquid. He reclaims used paper. Paper scrap is reprocessed by first being introduced into a chemical solution and then made into a slurry called pulp. The pulp is passed through screens to remove bits of plastic, etc. The next process is called de-inking, to remove printing and glue. A surfactant is mixed into the pulp to loosen the inks and glues from the pulp. Then air is bubbled up to float them to the top. What this customer needed is a way to vacuum off the foam created on the surface.

I suggested using a 4″ air amplifier connected to a vacuum hood.  The floating material was pushed towards the hood with a skimmer board and easily vacuumed away.

Joe Panfalone
Application Engineer
joepanfalone@exair.com

Which is better, Adjustable Spot Cooler or Cold Gun?

It is interesting to consider which product might be better, the Adjustable Spot Cooler or the Cold Gun. The usual American notion is most likely that bigger (more powerful) and more features is always better.

I would tend to challenge that notion though. When it comes to the Cold Gun, we have 4 very good choices to pick from. All of which have their place for the right application. We have two basic sizes, 1000 Btu/hr. and 2000 Btu/hr. It might be common sense on one hand to always say that 2000 Btu/hr. is better than the smaller capacity. But, what happens when you don’t have the compressed air volume to operate the larger unit?  You end up with a pressure drop in your compressor system which affects the performance of the Cold Gun and perhaps even other equipment that depends on steady pressure from the compressor system. So, in this thought process, perhaps the smaller 1000 Btu/hr. unit would be better to consider.

Now, let’s take the added dimension of adjustability of the temperature on the output flow as you have with the Adjustable Spot Cooler. In many cases having this flexibility is a very good attribute. For example, let’s say you have an application where you need a very specific temperature to test a thermostat. One batch requires 20F and the next batch might be -10F.  No problem with the Adjustable Spot Cooler.

Another example might be that the process requires that the temperature of the output flow really be dialed in exactly at the set point. The Adjustable Spot Cooler allows for this.

Another scenario might be that you have a process that requires spot cooling but you also have an operator who likes to turn knobs and push buttons because they think they know how best to set up anything within their realm (which isn’t always so). In this case a Cold Gun might be a better choice so that the operator doesn’t end up setting the Adjustable Spot Cooler to where it freezes up internally, which can happen at very extreme cold settings if the compressed air is not treated properly to lower the dew point.

Ultimately, what I’m trying to say is that for every application there is a good solution and this is why we have so many choices for our customers. If you need help determining which of these spot coolers might work better for you, please give us a call and we can help you sort the issues.

Neal Raker
Application Engineer
nealraker@exair.com

Preventive Cooling of an Electrical Control Panel

Machine downtime due to overheating of the electrical controls is unfortunately not at all uncommon.  But, there is a way to both prevent and treat the issue.  EXAIR offers Cabinet Coolers for just this purpose. 

I recently spoke to an OEM of slitters, rewinders, and other moving web equipment.  They are building a machine for a customer of theirs, and want to incorporate cooling in the machine control panel.  Because this is a new installation, and not treatment of an existing heat-related issue, there are no temperature measurements to take in order to calculate the heat load.  So, the estimated heat generation of the equipment to be installed was considered instead.  The enclosure itself is rated Nema 12 for dust and oil mist protection, and the equipment inside will be powered by 24VDC. 

Taking all of the above information into account, a model 4340-24VDC was the best choice to offer this customer.  This is a complete kit which includes the cooler itself, a cold air distribution hose kit to direct the cold air to hot spots, an automatic drain filter separator to remove water and dirt from the compressed air supply line and prevent it from entering the enclosure, a thermostat preset at 95°F to prevent over-cooling and excess air consumption while still maintaining a safe operating temperature of the equipment, and a 24VDC solenoid valve to activate the cooler based on the signals from the thermostat.

Installing this cooler system will provide all of the components they need to ensure and maintain a safe operating temperature inside the control panel.  This will prevent heat-related shutdowns of the machine and allow the web to move continuously with little, if any, downtime or re-feeds and restarts. 

Emily Mortimer
Application Engineer
emilymortimer@exair.com

Air Leaks: Not Worth Fixing?

False! Fix your leaks. They could be wasting an estimated 30% of your total compressed air. If you begin  to pay attention to your compressed air leaks and proactively start to fix them, you could have a system which is working better and save an additional 20% of compressed air losses.

My father-in-law has a workshop on the farm. He runs a 7.5 Hp compressor and keeps it on at all times. He does not use the compressed air too often but he wants it available immediately when he needs to use it. He runs one air line down the length of his barn for a local source of air at the other end.

At his compressor you can hear it leaking from a quick disconnect, and at the opposite end you can here it leaking from an air gun connection. His compressor will sit about 15 minutes before it powers up again to re-pressurize the system. He is simply using electricity to keep his pressure up on a system he might use once a day.

In an industrial environment it is difficult to always hear a small leak, but also recognize there will be many more leaks around due to the additional fittings and connections. The result is the same, your system is running more often to simply re-pressurize the losses you experience through leaks.

A good leak detection program starts by identifying the leaks, many times using an ultrasonic leak detector which is capable of identifying the leaks we would not normally hear. These leak spots can then be identified and fixed. Fixing leaks can reduce the overall time your compressor runs and extend its lifetime. This can also reduce maintenance costs by cutting down on the run time.

Ultrasonic leak detectors can be an inexpensive solution to an expensive problem. EXAIR can assist you with many more air savings products and solutions. If you have any questions for us let us know.

Kirk Edwards
Application Engineer
EXAIR Corporation

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