Tag: Submarine

“It’s Not Rocket Science”, or How Compressed Air Has Straightforward Applications In Aerospace

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On the submarine I served on, many of us used math, specific to our jobs. Torpedo (and missile) fire control, navigation, reactor operations…even meal cooking…involved certain formulas to accomplish particular tasks. One formula we all knew and kept near & dear to our hearts, though, was:

Number of surfaces = Number of dives

And those who fly aircraft and spacecraft, in – and out of – the atmosphere, have a similar formula:

Number of landings = Number of takeoffs

While this certainly requires a great deal of skill of the operators (as does diving and surfacing a submarine), it also takes a great deal of technical acumen in the engineering and construction of those aircraft & spacecraft (and warships). Terms like “aircraft grade” inspire a high degree of confidence in the integrity of materials, and rightly so – the quality standards that manufacturers and suppliers are held accountable to are stringent and inviolate. That’s why aerospace professionals need reliable, durable, and effective equipment to do their jobs.

EXAIR Corporation has been providing this kind of equipment to the aerospace industry (and others) since 1983. Here are some examples of the applications we’ve worked with “steely eyed missile men” to solve:

  • A jet engine manufacturer makes a titanium assembly consisting of a honeycomb shaped extrusion bonded to a rigid sheet. The cells of the honeycomb are only 1/8” wide, and 3/8” deep. After fabrication, they’re washed & rinsed, and the tiny cells tend to hold water. They would invert & tap the assembly to try to get the water out, but that wasn’t always effective and occasionally led to damaging the assembly. To reduce the chance of damage (and loss) of an assembly, they built a cleaning station, using EXAIR Model HP1125 2” High Power Super Air Nozzles and Model 9040 Foot Pedals, for hands-free control of the high force blow out of the honeycomb cells. The results were increased production, decreased defects, and lower labor costs.
  • A machine shop makes composite material parts for the aerospace industry. Static charge would build up, causing the shavings to cling to most of the surfaces inside the machine. The vacuum system was unable to overcome the force of the static charge to remove it, so they called EXAIR. Our expertise in static elimination led to the specification of a Model 8494 Gen4 Stay Set Ion Air Jet System to direct ionized air onto the tool during cutting. This eliminated the static as it was generated on the shavings, allowing the vacuum system to perform as advertised. Not only did it make for a cleaner work station, the air flow provided cooling for the cutting tool, improving performance & extending life.
  • If a company works with metal parts, there’s a decent chance they operate a welding machine, and those things make smoke & fumes that, at best, are a nuisance, and at worst, are toxic. An airplane repair shop that has to weld in tight spaces needed a convenient, portable, compact way to evacuate the welding smoke and fumes. They chose a Model 120024 4” Super Air Amplifier. They’re capable of pulling in over 700 SCFM, and with a sound level of only 73dBA and lightweight aluminum construction, they’re an ideal fit for this application.
  • Certain satellites have components whose batteries must be fully charged to ensure that everything works just right. Because of the heat that charging generates, they couldn’t be charged with the spacecraft on the launch pad without cooling. Conventional methods of providing cold air (refrigerant based or cold water chillers) are too bulky, so they instead use a Model 3230 Medium Vortex Tube, capable of providing 2,000 Btu/hr worth of cooling air flow. This enables them to charge the battery until just prior to launch, making sure the batteries are as fully charged as possible, prior to deployment.
  • While the lion’s share of Vortex Tube applications involve the use of their cold flow, a number of folks do use the hot air flow, with great success. A major material supplier to the aircraft & aerospace industry makes a flexible, porous strand of material that, after fabrication, passes through a wash tank prior to cutting to size. They wanted to speed up the drying time, but it was impractical to use electrically powered hot air blowers or heat guns. By using an EXAIR Model 3275 Large Vortex Tube set to a 70% Cold Fraction, they’re able to blow a little over 22 SCFM of 220°F air onto the strand, which effectively dries it to their specification, quickly & safely.
These are some of the EXAIR Intelligent Compressed Air Products used in the aerospace industry.

Exacting jobs call for safe, efficient, and reliable tools. Even if your job “isn’t rocket science”, the value of the right tool cannot be stressed enough. If you use – or want to use – compressed air for such a task, give me a call.

Russ Bowman, CCASS

Application Engineer
EXAIR Corporation
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“Math Wall” image courtesy of João Trindade, Creative Commons License

Five Things To Know About Single Acting Reciprocating Compressors

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With the development of highly efficient air compressors, there’s still a place for the most basic design: the single acting reciprocating compressor.  When the piston moves out of the cylinder, it draws air in, at atmospheric pressure.  When it moves in to the cylinder, it reduces the volume that air occupies, increasing its pressure.  These machines are durable, effective, relatively inexpensive, and pretty easy to maintain.  Here are a few interesting things to know about them:

1. Popularity. Because of the simplicity of their design, they’re the most common air compressor in the 10HP and under sizes.  You can get them from a number of sources, and they’re not going to set you back as much as some other types.
2. Oil free air (part 1) While the most basic design uses oil to lubricate the piston rings in the compression cylinder, oil-less reciprocating compressors have cylinders with very smooth (and hard) bore surfaces, like nickel or chrome plating. A series of guide rings around the whole circumference of the piston prevent metal-to-metal contact, eliminating the need for liquid lubrication in the compression cylinder.
3. Oil free air (part 2) If oil in your compressed air is a problem, an oil-free (as opposed to oil-less) compressor is another option. While an oil-less compressor doesn’t use lubricant for the piston movement, an oil-free compressor’s moving parts are oil lubricated, but that oil is kept away from the compression cylinder(s) with connecting rod(s) so that the oil is confined to the lower moving parts…the crankshaft and bottom ends of the connecting rods, and away from the pistons & compression cylinders.
4. Foundation. Reciprocating machinery, as the name implies, has parts that move back and forth. The sudden reversal of direction of heavy metal pistons & rods, dozens of times a minute, means that their operation is inherently unbalanced. This out-of-balance condition, though, can be absorbed by properly securing the compressor to a properly prepared foundation.
5. Higher pressures. If your facility’s compressed air usage primarily entails pneumatic tools, cylinders, and blow off devices like air guns, the system header pressure is likely maintained at around 100psig. While a one-stage reciprocating compressor is usually rated for discharge pressures up to 125psig, a second stage can increase that to 175psig. Multi-stage compressors are used for applications that require up to 3,000psig compressed air. Examples of these are scuba breathing air, pneumatic excavators, and my personal favorite: ballast tank blowing air, used to surface a submarine.

4-stage reciprocating compressors charge 3,000psig air tanks that are used to rapidly push water from a submarine’s ballast tanks to create positive buoyancy.  Because keeping your ‘diving-to-surfacing’ ratio at 1:1 is important.

At EXAIR Corporation, helping you get the most out of your compressed air system is important to us.  If you’ve got questions about how to do just that, give me a call.

Russ Bowman
Application Engineer
EXAIR Corporation
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EXAIR Cabinet Cooler System Used on Cement Barge

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I joined the Navy, right after high school, to get out of Ohio, see the world, and never come back. “My recruiter said” (if you are considering military service, those can be famous last words, just so you know) that I would be a good candidate for Nuclear Power School, so I took the test. As a math & science nerd scholar, I qualified for admission easily.  About halfway through Nuke School, I volunteered for submarines.  My decision was based in no small part on the sea stories of our instructors, the strong reputation of better food, and my deep appreciation for the movie “Operation Petticoat.”

Upon graduation, I was assigned to a new construction Trident submarine.  I did not see the world…I saw the Electric Boat shipyard in Groton, Connecticut, and Naval Submarine Base King’s Bay, Georgia.  Hilarity occasionally ensued, but never in the context of that movie I so adored.  I moved back to Ohio (on purpose) soon after my enlistment was up.  The food WAS good…I can unreservedly vouch for that.

In the new construction environment of the shipyard, I became quite familiar, and developed a deep respect for, the high level of attention paid to the materials and workmanship that a seagoing vessel demanded…not to mention, one with a nuclear reactor on board.  Reliability and durability are obviously key factors.

I had the pleasure recently of assisting an electrical contractor who was looking for a cooling solution for a new Variable Frequency Drive enclosure installation on a cement barge.  The ship’s engineer (a Navy veteran himself) had told the contractor that his priorities were reliability, durability, and dust exclusion.  He couldn’t have made a better case for an EXAIR Cabinet Cooling System.

Based on the specified heat load of the VFD, the size of the enclosure, and its location, a Model 4380 Thermostat Controlled NEMA 12 Cabinet Cooler System, rated at 5,600 Btu/hr, was specified.  This equipment is internal to the ship; had it been exposed to the elements, a NEMA 4X system would have been presented.

Up to 2,800 Btu/hr cooling capacity with a single Cabinet Cooler System (left) or as much as 5,600 Btu/hr with a Dual system (right.)

EXAIR Cabinet Cooler Systems have no moving parts to wear, no electric motor to burn out, and no heat transfer surfaces (like a refrigerant-based unit’s fins & tubes) to foul.  Once it’s properly installed on a sealed enclosure, the internal components never see anything but cold, clean air.

If you have a need to protect an electrical enclosure in aggressive environment, give me a call.  With a wide range of Cabinet Cooler Systems to meet a variety of needs, we’ve got the one you’re looking for, in stock and ready to ship.

Russ Bowman
Application Engineer
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Optimizing Compressed Air with EXAIR Innovative Static Eliminators

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A dear friend is turning 50 this month, and I have no intention of making a big deal of it, considering the spectacle that her husband (who is younger than both of us) is no doubt going to make of it. I was reminded of her impending birthday when I read that Alvin is also turning 50 this year.

Even at this depth, Alvin doesn't look a day over 49.
Even at this depth, Alvin doesn’t look a day over 49.

Alvin (DSV-2) is a deep-dive submersible, built in 1964. Built to dive to depths of over 8,000 feet, Alvin has had quite a storied career:

  • 1966 – Used to locate a hydrogen bomb that was lost off the coast of Spain when a US Air Force bomber “had an accident.” The bomb was retrieved a few weeks later, without incident.
  • 1967 – On dive #202, Alvin was attacked by a swordfish, at a depth of about 2,000 feet. The swordfish became entangled, forcing an emergency surface. Upon removal, the swordfish was cooked for dinner.
  • 1968 – Alvin’s tender ship accidentally dropped Alvin when some steel cables snapped, in the middle of the ocean. Three crew members onboard at the time were able to escape, but left their lunches behind. Severe weather and the development of the required technology put off Alvin’s recovery for almost a full year. A full rehab of the vessel was slated. The fruit and sandwiches left behind were found to be well preserved, and soggy but edible.
  • 1986 – Alvin was used to find the wreckage of the Titanic. While the mission was making headlines at the time, it was actually a cover story for the highly classified “real” operation: the search for USS Scorpion (SSN-589), lost under unknown circumstances in 1968. In a remarkable stroke of good fortune, both vessels were found.

That’s all neat stuff, but I’m sure there are a few spine tingling stories we’ll never hear about a deep submergence vessel, operated by the US Navy, during the height of the Cold War. Another bit of interesting trivia, though, is who built Alvin: General Mills. That’s right, the breakfast cereal folks. Turns out, they had an electromechanical division back then that pioneered advances in packaging technology, and had previously applied some of their mechanical arms to other submersibles, leading them to successfully bid the project that Alvin was born from.

This, of course, is what engineers do. EXAIR has been making Intelligent Compressed Air Products, aimed at optimizing compressed air use, increasing safety, and lowering noise levels for over 31 years now. Along the way, we’ve added products, and added TO our products to meet other frequent needs of our customers.

Consider the Air Knife: the Air Knife had been a product for years when EXAIR developed the Ionizing Bar  and added it to the Air Knife to turn it into an efficient, quiet, and safe Static Eliminator. The Air Knife then provided good information toward development of the super efficient Super Air Knife which has become the hallmark of efficiency and performance within industry.  After years of successfully solving thousands upon thousands of static dissipation applications with the Super Air Knife, we recently added one-piece designs from 60 – 108” long which used to be a two piece construction.

3to54 siak
EXAIR stock SIXTEEN different lengths, from 3″ to 108″. Custom lengths are available in as little as three days.

A quick look at our complete and comprehensive line of Static Eliminator products shows that, if you’ve got a static problem – big or small – we’ve likely got a solution for it.

Russ Bowman
Application Engineer
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expl1874 image courtesy of NOAA Photo Library.  Creative Commons License