The Importance of Compressed Air Filtration

In this blog, I would like to turn your attention to our accessories that support our Intelligent Compressed Air® Products; the Filter Separator and the Oil Removing Filter.  EXAIR products use compressed air to coat, conserve, cool, convey and clean.  So, to keep our products running properly and efficiently, we need to supply them with clean, pressurized air.  If we look at the two types of filters that we offer, we can see how they can play an important part in your compressed air system.

Filter Separators

Filter separators are used to remove bulk liquid and contamination from the compressed air stream.  They have a 5-micron filter and work very well if you get a slug of liquid in your compressed air system.  They use mechanical separation to remove the large particles of dirt and water from the air stream.

Most facilities use some type of compressed air dryer in their system to dry and condition the compressed air.  But, if a system failure occurs, then water, oil, and dirt can be pushed into the compressed air lines and perhaps into your EXAIR products.

Even if you have good quality air, it is still important to keep your products protected.  I would consider the Filter Separator as a minimum level of protection that should be used.

Oil Removal Filters

The Oil Removal Filters are used to keep the compressed air even cleaner yet.  They work great at removing very small particles of dirt and oil.  The 0.03-micron media of the Oil Removal Filter is designed to “coalesce” the fine liquid particles into large droplets.

Thus, allowing gravity to remove it from the compressed air stream.  Some common issues allow for dirt and oil particles to collect in “dead” zones within the air lines.  As it piles up and grows, portions can break off and get into the air stream affecting pneumatic devices.

The Oil Removal Filter will be able to help eliminate this long-term problem in your compressed air system.  As a note, Oil Removal Filters are not great for bulk separation.  If you have a system with lots of water, you should use a Filter Separator in front of the Oil Removal Filter to optimize the filtration.

Now that we went through each type, how do we use them together to get the best supply of compressed air?  We always want them to be installed upstream of a Regulator.  This is because the velocity is lower at higher pressures.

Lower velocities mean lower pressure drops which is great for supplying the proper amount of compressed air to EXAIR products.  If you are using a combination of both filters, the Filter Separator will be upstream of the Oil Removal Filter.  The Filter Separator will knock down the large particles and liquid slugs allowing the Oil Removal Filter to remove the smaller droplets and particles.

EXAIR offers a range of sizes to help support our products.  They range from ¼” NPT ports up to 1 ½” NPT ports.  The size of the ports determines the flow rating for each unit.  EXAIR also has Mounting Brackets to mount the filters to walls or frames.

To support each type of filter, we have replacement elements and bowl kits.  Since the function of the filter is to remove debris, we recommend to change the filter element once a year or when it reaches 10 PSID pressure drop; whichever comes first.

If we can analyze the compressed air systems, I would like to categorize it into a good and premium quality.  For the good quality of compressed air, you can have the compressed air run through the Filter Separator.  For the premium quality of compressed air, you can have your compressed air run through the Filter Separator and then through the Oil Removal Filter.

With clean quality air, your EXAIR products will provide you with effective, long-lasting performance without maintenance downtime.

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

6 Basic Steps for Good Air Compressor Maintenance (And When to Do Them)

A production equipment mechanic with the 76th Maintenance Group, takes meter readings of the oil pressure and temperature, cooling water temperature and the output temperature on one of two 1,750 horsepower compressors. (Air Force photo by Ron Mullan)

In one of my previous jobs, I was responsible for the operation of the facility.  One of my biggest responsibilities was the air compressor because it supplied pressurized air though out the facility to feed the pneumatic systems.  Like with many industries, the compressor system is the life blood of the company.  If the compressor fails, the whole facility will stop.  In this blog, I will share some preventative maintenance items and schedules for your air compressors.

Because the cost to make compressed air is so expensive, compressed air systems are considered to be a fourth utility.  And with any important investment, you would like to keep it operating as long and efficiently as possible.  To do this, it is recommended to get your air compressor a “checkup” every so often.  I will cover some important items to check as well as a recommended schedule for checking.  Depending on the size of your air compressors, some items may or may not apply.

1. Intake filter:  The intake filter is used to clean the air that is being drawn into the air compressor.  Particles can damage the air pump mechanisms, so it is important to have the proper filtration level.  But, as the intake filter builds up with debris, the pressure drop will increase.  If they are not properly monitored and cleaned, the air flow will be restricted.  This can cause the motors to operate harder and hotter as well as reduce the efficiency of the air compressor.

2. Compressor Oil:  This would be for flooded screws and reciprocating compressors that use oil to operate the air pump.  Most systems will have an oil sight gauge to verify proper levels.  In larger systems, the oil can be checked for acidity which will tell you the level at which the oil is breaking down.  The oil, like in your car, has to be changed after so many hours of operation.  This is critical to keep the air pump running smoothly without service interruptions.

3. Belts and Couplings:  These items transmit the power from the motor to the air pump.  Check their alignment, condition, and tension (belts only) as specified by the manufacturer.  You should have spares on hand in case of any failures.

4. Air/Oil Separators:  This filter removes as much oil from the compressed air before it travels downstream.  It returns the oil back to the sump of the air compressor.  If the Air/Oil Separator builds too much pressure drop or gets damaged, excess oil will travel downstream.  Not only will the air pump lose the required oil level, but it will also affect the performance of downstream parts like your air dryer and after cooler.

5. Internal filters:  Some air compressors will come with an attached refrigerated air dryer.   With these types of air compressors, they will place coalescing filters to remove any residual oil.  These filters should be checked for pressure drop.  If the pressure drop gets too high, then it will rob your compressed air system of air pressure.  Some filters come with a pressure drop indicator which can help you to determine the life of the internal filter element.

6. Unloader valve:  When an air compressor unloads, this valve will help to remove any compressed air that is trapped in the cavity of the air pump.  So, when the air compressor restarts, it does not have to “work” against this “trapped” air pressure.  If they do not fully unload, the air compressor will have to work much harder to restart, wasting energy.

Preventative maintenance is very important, and checks need to be performed periodically.  As for a schedule, I created a rough sequence to verify, change, or clean certain items that are important to your air compressor.  You can also check with your local compressor representative for a more detailed maintenance schedule.

Daily:

  • After stopping, remove any condensate from the receiver tank.
  • Check oil level.

Monthly:

  • Inspect cooling fins on air pump. Clean if necessary
  • Inspect oil cooler. Clean if necessary

Quarterly:

  • Inspect the inlet air filter. Clean or replace if necessary.
  • Check the belt for tension and cracks. Tighten or replace.
  • Check differential pressure indicators on outlet compressed air filters.

Yearly:

  • Replace Air Inlet Filter
  • Replace the air-oil separator
  • Test safety valves and unloader valve
  • Replace compressed air filters
  • Change oil
  • Grease bearings if required

Keeping your air compressor running optimally is very important for pneumatic operations and energy savings.  I shared some important information above to assist.  Another area to check would be your pneumatic system downstream of the air compressor.  EXAIR manufactures engineered products that can reduce air consumption rates.  You can contact an Application Engineer to discuss further on how we can save you energy, money, and your air compressor.

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

 

What’s The Big Deal About Clean Air?

Compressed air isn’t called manufacturing’s “Fourth Utility” (the first three being electricity, water, and natural gas) for nothing. Pneumatic tools are popular because they’re often so much lighter than their electric counterparts. Compressed air can be stored in receiver tanks for use when other power supplies are unavailable or not feasible. Many compressed air operated products can be made to withstand environmental factors (high/low temperature, corrosive elements, atmospheric dust, oil, other contaminants, etc.,) that would make electric devices very expensive, unwieldy, or impractical.

One of the most valuable considerations, though, is that your compressed air system is, by and large, under your control.  The type and capacity of your air compressor can be determined by your specific operational needs.  The header pressure in your supply lines is based on the applications that your air-operated devices are used for.  And the performance & lifespan of every single component in your compressed air system is determined by the care you take in maintaining it.

I covered the importance of compressed air system maintenance in a blog a while back…today, I want to focus on clean air.  And, like the title (hopefully) makes you think, it’s a REALLY big deal.  Consider the effects of the following:

Debris: solid particulates can enter your air system through the compressor intake, during maintenance, or if lines are undone and remade.  If you have moisture in your air (more on that in a minute,) that can promote corrosion inside your pipes, and rust can flake off in there.  Almost all of your air operated products have moving parts, tight passages, or both…debris is just plain bad for them.  And if you use air for blow off (cleaning, drying, etc.,) keep in mind that anything in your compressed air system will almost certainly get on your product.

Your compressed air system may be equipped with a main filter at the compressor discharge.  This is fine, but since there is indeed potential for downstream ingress (as mentioned above,) point-of-use filtration is good engineering practice.  EXAIR recommends particulate filtration to 5 microns for most of our products.

Water: moisture is almost always a product of condensation, but it can also be introduced through faulty maintenance, or by failure of the compressor’s drying or cooling systems.  Any way it happens, it’s also easy to combat with point-of-use filtration.

EXAIR includes an Automatic Drain Filter Separator in our product kits to address both of these concerns.  A particulate filter element traps solids, and a centrifugal element “spins” any moisture out, collecting it in the bowl, which is periodically drained (automatically, as the name implies) by a float.

Point of use filtration is key to the performance of your compressed air products, and their effectiveness. Regardless of your application, EXAIR has Filter Separators to meet most any need.

Oil: many pneumatic tools require oil for proper operation, so, instead of removing it, there’s going to be a dedicated lubricator, putting oil in the air on purpose.  Optimally, this will be as close to the tool as possible, because not all of your compressed air loads need oil…especially your blow offs.  If, however, a blow off device is installed downstream of a lubricator (perhaps due to convenience or necessity,) you’ll want to do something about that oil. Remember, anything in your system will get blown onto your product.

If this is the case, or you just want to have the cleanest air possible (keep in mind there is no downside to that,) consider an EXAIR Oil Removal Filter.  They come in a range of capacities, up to 310 SCFM (8,773 SLPM,) and the coalescing element also offers additional particulate filtration to 0.03 microns.

In closing, here’s a video that shows you, up close and personal, the difference that proper filtration can make:

If you’d like to discuss or debate (spoiler alert: I’ll win) the importance of clean air, and how EXAIR can help, give me a call.

Russ Bowman
Application Engineer
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Vacuum Generator System Selection – EXAIR E-Vacs

E-Vac Vacuum Generators are a highly efficient, versatile compressed air vacuum pump. Their versatility allows them to be adapted to many applications such as pick and place, clamping or vacuum forming. They’ve also been used in more unique applications like wood veneer pressing and basketball deflation.

EXAIR manufactures (3) types of E-Vacs – Low vacuum generators for porous materials, like cardboard, generating up to 21″ Hg with vacuum flows as high as 18.5 SCFM. Our high vacuum generators, designed for use with non-porous materials like glass or steel sheets, produce vacuum levels up to 27″ Hg and up to 15.8 SCFM of vacuum flow. The adjustable generators provide flexible vacuum performance, up to 25″ Hg and 81 SCFM,  which can be easily adapted to meet the application.

EXAIR E-Vacs provide instantaneous vacuum response, and are engineered for high efficiency to minimize air consumption.

 

When making a selection, there are a few key areas you want to consider:

Is the material porous or non-porous?

  • This will allow you to select the proper type of vacuum generator to fit the application and the type of vacuum cup best suited for the process.

 

What is the weight of the part and how will it be lifted?

  • If the part is being lifted where the vacuum cups will be positioned horizontally, like on top of a sheet of glass, you want to use a safety factor of 2 times the actual weight of the part. In processes requiring the cups be positioned vertically on the part, such as picking up a sheet of plywood and hanging it on an overhead conveyor, a safety factor of 4 would be used.

 

How many Vacuum Cups do I need?

  • Consider the quantity and placement to evenly distribute the weight for safely moving the material.
  • Depending on the maximum vacuum the generator produce, how much weight can each cup lift?
  • Make the cup selection per the following chart

 

Once you have selected the type and number of cups needed, you can then begin to look at which additional accessories items you might need.

  • Filters – supplying clean, dry air is key for maintaining optimal performance. An automatic drain filter  can be used to remove any water or contaminants in the supply line. If there is oil present, consider using an Oil Removal Filter.
  • Mufflers – help to reduce the noise level without restricting the airflow. We offer 2 different styles – Standard and Straight Through. Standards mufflers are a good choice where the supply air is clean and dry. These mufflers can only be used with the porous and non-porous generators. The Straight Through mufflers reduces sound levels by up to 26 dBA and are the better choice in processes where dirt or particulate may be present.
  • Tubing and Fittings – polyurethane tubing is available in 10′ sections up to 50′ for processes requiring the vacuum cups be placed in a location that wouldn’t allow for direct mounting to the NPT vacuum port on the generator or where multiple cups are needed. You want to keep the length of tubing as short as possible though for effective pickup and release time.
  • Check Valve – will maintain vacuum on the load if the supply pressure were to drop or be lost during operation.

For additional assistance selecting the proper E-Vac and accessories for your process, please contact an application engineer at 800-903-9247.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

 

Oil And Water Don’t Mix, But Oil And Air Sure Do

Do you have oil in your compressed air system? It may be there on purpose…air operated tools require it, and there are a number of devices on the market that provide a precise amount of oil to keep the moving parts in these tools well lubricated and properly operating.

If it’s not there on purpose, it’s not necessarily a problem, though, and it’s hardly uncommon. Many air compressors are oil lubricated, which means there’s oil being pumped at a constant rate, directly towards the piston rings, and a little bit is always going to end up in the air. As the rings wear, even more makes it past…this is impossible to prevent, but, with proper maintenance, it’s kept to a very minimal amount. There are, of course, oil-less compressor designs, which can eliminate this entirely, but they’ve been known to carry a little heavier price tag. Some situations, though, make them worth every penny.

Trace amounts of oil like this don’t affect a lot of compressed air applications, including the performance of most of our products. There are times, however, when oil needs to be addressed…for instance:

*Blow off prior to painting or coating. Even trace amounts of oil on a surface to be painted can cause big problems.
*Electrical enclosure cooling. Oil won’t affect the heat removal performance of an EXAIR Cabinet Cooler System, but it can indeed cause serious issues with electrical/electronic components and devices if it’s present in the cold air that’s blowing on them.
*Air operated conveyors. Likewise, oil won’t hurt the performance of a Line Vac, but keep in mind that anything in the air supply will get on the material or product you’re conveying.
*Static Eliminators. Here’s a situation where oil in the air WILL have an effect on product performance…the emitter points of your EXAIR Static Eliminator need to be kept clean (including oil free) for proper operation. And, again, anything in your air is going to get onto your product.

This is where proper filtration comes in: properly installed downstream of a Filter Separator, EXAIR’s coalescing Oil Removal Filters take out even trace amounts of oil from the air flow, ensuring your process doesn’t see anything but clean, dry air.

EXAIR Model 9027 Oil Removal Filter, installed between Model 9004 Filter Separator and 9008 Pressure Regulator, using our Modular Coupling Kits
EXAIR Model 9027 Oil Removal Filter, installed between Model 9004 Automatic Drain Filter Separator and 9008 Pressure Regulator, using our Modular Coupling Kits.

Again, oil in your air isn’t always a problem. If you have questions about your application, though, give us a call…if it IS a problem, we’ve got a solution.

Russ Bowman
Application Engineer
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