Month: July 2016

Compressed Air Vacs have Advantages Over Electric Vacuums – Durability, Reliability, Noise Levels

Published on by John BallLeave a comment

Have you ever heard an electric vacuum toward the end of its life? It gets this high pitch annoying noise caused by the bearings going out.  I spoke recently to a customer who was hearing it about every two months.   This company cuts ceramic tiles with a diamond-tooth circular saw.  During this operation, a lot of dust is being created.  He would attach an electric vacuum to the dust port of the saw housing.  The vacuum was to remove as much dust as possible from the sawing operation to keep the area clean and the operators safe.  After about two months of operation, they would start hearing that “moan” from their electric vacuum.  The performance of the vacuum started to drop off, and it would allow more dust to collect in the saw room.  This was a hazard as it would make the floor slippery.  The operators then had to stop operations early to clean the floors at the end of each shift.  After their second electric vacuum failed, they started looking for a better alternative.

Heavy Duty HEPA Vac Family
Heavy Duty HEPA Vac Family

When they contacted me about their issue, I knew immediately which EXAIR product would serve their need very well. I suggested our new model 6399-30, 30 gallon Premium Heavy Duty HEPA Vac system for this operation.  The 30 gallon size is the smallest in the Heavy Duty HEPA family which made it easy to fit behind the saw table away from the operators.  The HEPA filter inside has an efficiency of 99.97% at 0.3 micron.  So, the dust will remain in the drum and not migrate back into the ambient air.  The EXAIR vacuum generator has no moving parts or bearings to wear.  It is made from a hardened steel construction which is very resistant to wear and abrasion from materials like ceramic.  The EXAIR design can generate a high vacuum level to draw dust material at an extremely high rate, and it only has a decibel level of 82 dBA.  With clean compressed air, this vacuum will last for years and years; not months.

As this company installed the Heavy Duty HEPA Vac into their system, the first thing that they noticed was how quiet it operated. The constant loud noise from their electric vacuum was gone, making it a better working environment.  They also noticed that the dust was being removed very quickly by the powerful vacuum pressure.  This meant that the amount of dust that could collect on the floor and equipment was greatly reduced.  Since the floors were cleaner longer, it decreased shut down times and removed the constant hazard of a slippery floor.

If you find that you are going through your electric vacuums or just would like to reduce the noise levels, EXAIR has a large line of Industrial Housekeeping Products. You can contact us to see if we have the right vacuum product for you.

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

Super Air Knife Provides Engine Block Blowoff

Published on by Lee EvansLeave a comment
Photo-0
Extra points if you can identify this engine block

My hobby with cars is no secret.  Most people who meet me come to know I’m a total gearhead.  Case in point, on a recent trip to visit with our distributor in Finland, I was asked about the car I was working on when they last visited us just a few months ago.  Since then, the aforementioned car (a blue BMW) has found a new home, and I’m gearing up to sell another.

So, when I received an email from a major auto manufacturer needing a solution to clean the top side of an engine block, I was intrigued.  In addition to the photo above, I received the photo below with a short description of the current state in the application.

Photo-1
The top deck of this block, where the cylinder head gasket will rest, has a width of approximately 200mm.

As it stands, coolant is accumulating on the top side of the engine block after they are fully cast, decked, and cleaned.  In order to move on to the next step in the process, these engine blocks need to have all residual oil removed from the top side of the block.

The solution?  A 9” (229mm) Super Air Knife installed above the engine blocks as they travel down the production line.  The Super Air Knife will install at a 45° angle of attack, blowing off the residual coolant and allowing these parts to move on in the process without stopping.  This prevents lost throughput due to stoppage of the production line, prevents increased costs due to personnel needing to treat each engine block by hand, and provides a uniform condition for the engine blocks when they arrive in the next step of this production process.

The best part of the interaction was that this auto manufacturer contacted EXAIR for a solution because they were able to solve previous problems with overheating electrical control panels using our Cabinet Coolers.  So, when they needed another compressed air solution, they immediately knew who to call.

If you have an application in need of a compressed air solution, give us a call.  We’ll be happy to help.

Lee Evans
Application Engineer
LeeEvans@EXAIR.com
@EXAIR_LE

Vacuum Evacuation Time for E-Vacs

Published on by John BallLeave a comment

A tank manufacturer was building specially designed tanks for their customer. These tanks were to hold cryogenic materials, so they had to create an outer shell to hold a special type of insulation material.  This shell maintained a 1/2 inch (13 mm) gap around the tank.  The overall dimensions of the cylindrical tanks were 10 feet (3 meters) in diameter and 43 feet (13 meters) in length.  The internal volume of the gapped area was 56.1 cubic feet (1560 liters).  With this type of insulation, it had to be under a negative pressure, or vacuum, to help facilitate the insulation properties.  So, when the tanks were completed, they had to check for leaks between the shell and the tank.  The requirement was to draw a vacuum to 21” Hg  and to hold it at that level for 30 minutes.  As the tank manufacturer researched vacuum pumps to test their design, they came across EXAIR.

Being that they were not familiar with EXAIR E-Vacs, they wondered how they worked. I explained that the E-Vac uses compressed air to create a vacuum by a venturi method.  It can reach vacuum levels up to 27” Hg in a very compact and lightweight design.  Being that they do not have any moving parts, they are very durable and long lasting in systems with on/off cycling or continuous running.  The tank manufacturer was very intrigued by this concept as they had electric vacuum pumps fail in the past.

He wondered about the evacuation time to get to 21” Hg of vacuum. The idea for the leak test was to reach the vacuum level and turn a valve off to isolate the area.  From there, they would watch a gage to see if they were losing vacuum.  If so, then they would have to find and fix the leak and recheck.  If the vacuum pressure held, then they could fill the area between the shell and the tank with insulation material; use the E-Vac to put it under vacuum; and cap.  Because the volume was large and time was a concern, I suggested the model 840060M.  This had the highest vacuum flow rate and can reach a vacuum level of 25” Hg.

Adjustable E-Vacs
Adjustable E-Vacs

To help explain a little better about vacuums, when you are near atmospheric pressure, you have the highest air flow rates. As the vacuum levels rise, less air is present to be drawn out.  When you reach the vacuum pump capacity or complete vacuum, the flow rate is zero.  You can notice this with your vacuum at home.  As you turn the vacuum on, the air is rushing in (the highest flow rate/very low vacuum pressure).  As you cover it with your hand, the vacuum pressure increases and the flow rate decreases to zero (no flow rate/highest vacuum pressure). To figure the amount of time to reach a certain vacuum level, we have to take into consideration the different flow rates as the vacuum level continues to increase.  The equation that we use is below:

Equation 1:  t = V * ln(p0 / p1)  / q

t = evacuation time (min)

V = enclosed volume (ft^3)

p0 = atmospheric pressure (“Hg)

p1 = end vacuum pressure (“Hg)

q = flow rate of vacuum pump (SCFM)

With the performance data of the model 840060M E-Vac, we can start to calculate the time to reach 21” Hg vacuum. A couple of details are required to make the equation work properly.  Just as a note, the end vacuum pressure, p1, has to be converted to an absolute pressure. This will equate to 29.92” Hg – 21” Hg = 8.92” Hg (absolute).

Here are the details for Equation 1:

V = 56.1 ft^3 (above)

p0 = 29.92” Hg (absolute start)

p1 = 8.92” Hg (absolute target)

q = 70 SCFM (cataloged at 80 psig)

Thus,

t = V * ln(p0 / p1) / q

t = 56.1 ft^3 * ln(29.92” Hg/8.92” Hg) / 70 SCFM

t = 0.97 minutes

For this application, the model 840060M worked great for both procedures. With less than 1 minute to get to the desired set point, it didn’t hinder production for leak checks or to vacuum set the insulation. If you have a timing sequence with vacuum chambers or “pick and place” systems, you can use this equation to find the best E to meet your goal.  If you need any additional help, you can always contact an Application Engineer at EXAIR.

John Ball

Application Engineer

Email: johnball@exair.com

Twitter: @EXAIR_jb

Practice Makes Perfect

Published on by exaircorpLeave a comment
2016 Eagles
NEW Eagles Football Jersey for 2016

Last year, I wrote a few blogs about how I was an assistant coach for my oldest son’s youth football team. We had an amazing season that ended with a 2nd round playoff loss and a 3rd place finish overall. Not too shabby for a new group of players and coaches. Now, the new season is upon us with practice beginning next Monday. Our new roster is pretty much the opposite of last season, as we now have 11 returning players from last year’s team and 4 newcomers. The coaching staff has stayed intact as well, so we are hoping to improve on last year’s successes and bring home the championship this year! But hey, we are talking about 7 and 8 year old boys here, so ANY type of success is a win in itself.

After a brief coaches meeting over the weekend, we have decided to hold practice 3 days a week this year, compared to 2 days last. We are hoping the extra practice will help us implement some more pass plays in the offense and work on extending our defensive sets, which cost us at the end of last year. For me personally, I am excited to see how my own son has grown from his first season of learning how to block and tackle the right way, to being more involved in the offense. He is one of the fastest kids on the team but got a little nervous whenever we tried to get him the ball on a rush or pass play. He and I have spent A LOT of time this spring and early summer, throwing the ball and working on his ball carrying skills. From what I’ve seen in our yard, I am pretty excited to see what unfolds on the football field. I keep telling him that he’s going to have some dropped passes and fumbled balls, but the important thing is to not get discouraged and keep trying. After all, practice makes perfect.

Here at EXAIR, we adopt the same philosophy. We are dedicated to putting in the time and effort to develop new and useful compressed air operated products. The following is a list of some new products now available:

  • New 2.5″ and 3″ Line Vac and Threaded Line Vac in 316SS and High Temperature construction

    Standard Line Vac: aluminum or SS
    Standard Line Vac in aluminum or stainless steel
  • New 2.5″ and 3″ Heavy Duty Line Vac with smooth or threaded ends. Hardened Alloy Construction for better abrasion resistance.

    Heavy Duty Line Vac: Hardened Alloy Construction and High Performance
    Heavy Duty Line Vac: Hardened Alloy Construction and High Performance

To discuss these new products or any EXAIR product, please contact an application engineer for assistance.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN