Tag: pressure

Week 6 Back to Basics- Control the Pressure

Published on by Brian FarnoLeave a comment

If you’ve been following along with this blog miniseries, you know we’ve reached the final step in the Six Steps to Optimizing Your Compressed Air System. Each step so far has built toward this moment—and today we add the last piece of the puzzle.

The final step is simple but powerful: control the air pressure at the point of use to minimize consumption.

EXAIR offers a range of Pressure Regulators capable of handling air flow of up to 700 SCFM.

This is done by installing one of our pressure regulators, available in multiple pipe sizes and flow capacities. A small change in pressure makes a big impact. For example, reducing operating pressure from 100 PSIG to 80 PSIG lowers energy use by nearly 20%. In many cases, operations can run at even lower pressures, unlocking even greater savings.

This reduction in energy use is also coupled with the fact that pressure regulators make any compressed air-operated tool infinitely adjustable. Not all applications require the full output force or RPM, or conveying rate that can be achieved at full line pressure with a compressed air-operated product. And so the humble pressure regulator enables this ability for energy savings and control that is on par with any electrical control for voltage or even frequency. Pressure regulators also facilitate our working mantra to use the least amount of pressure and volume necessary to accommodate the application objectives.

All of our regulators are standard stock items, which means they can ship the same day if ordered by 2:00 P.M. Eastern Time. Plus, with 2D and 3D CAD models available through our CAD Library, you can design your entire compressed air system virtually before making a single cut in pipe.

This step, combined with the previous five, gives you a complete roadmap to compressed air optimization. From measuring usage and fixing leaks, to implementing engineered solutions, automating control, using intermediate storage, and now regulating pressure—EXAIR is here to help make the process straightforward and effective.

As always, if you’d like to discuss your application or explore how we can help you optimize your compressed air system, feel free to reach out.

Brian Farno, MBA – CCASS Application Engineer

BrianFarno@EXAIR.com
@EXAIR_BF

Pressure Drop vs Differential Pressure

Published on by John BallLeave a comment

I find myself interchanging these terms; pressure drop and differential pressure.  This is very common as both are determined by the change in pressure between two points.  In this blog, I will cover the difference between these two terms in my view.

Pressure drop only occurs when the air is flowing.  The higher the velocity, the higher the pressure drop.  Velocity is created when the pressure changes.  So, the higher pressure will go toward the lower pressure.  But we wish that pressure difference to be as low as possible.  Pressure drops are always a loss, and you cannot regain that energy.  Forms of pressure drop that can be found are small diameter pipes or tubing; restrictive fittings like quick disconnects, and undersized conditioning equipment like after coolers and air dryers.  If a pressure drop is too large, the pneumatic equipment will not have enough power to operate effectively and efficiently.  I have another blog with a video that helps demonstrate this, “Pressure Drop and its Relationship to Compressed Air”. 

Differential pressure can be static or flowing.  It is very similar to pressure drop except that the energy is stored.  The most common device that does this is the pressure regulator.  You can reduce the pressure downstream to the point-of-use.  This type of pressure reduction will save you money, instead of wasting money.  For every 10 PSI reduction in pressure, it will save you 5% in energy.  With blow-off devices, you want to use the least amount of pressure to “do the job”.  Over-driving compressed air pressure is a common and wasteful condition found in facilities.

Here is a graph of a typical compressed air system.  As you can see, the typical pressure drop from the air compressor to the point-of-use.  So, if you can reduce the pressure drop through the system and optimize the differential pressure from the regulator to your point-of-use, you can enhance your compressed air system.

Pressure Drop Chart

In a simple statement, pressure drop loses energy while differential pressure stores energy for later use.  EXAIR offers a variety of efficient, safe, and effective compressed air products to fit within the demand side and which can help to reduce pressure drops within a system.  This will include the EXAIR Super Air Knives, Super Air Nozzles, and Safety Air Guns.  If you wish to go further in optimizing your system, an Application Engineer at EXAIR will be happy to help you.

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

How To Prevent Pressure Drops

Published on by jasonkirbyLeave a comment
Issue 1

Compressed air serves as the essential utility for operation, and its performance limitations are determined by the supply available. To effectively utilize EXAIR products and pneumatic equipment, it is crucial to establish a method for transferring compressed air from the source to the point of use. This can be accomplished through three primary means: pipes, hoses, and tubes.

As compressed air travels through the distribution system, it experiences friction against the inner surfaces of pipes, tubes, and hoses. Factors such as the diameter of the pipe, its length, the number of bends, and the smoothness of the inner wall contribute to this friction. Consequently, a reduction in air pressure occurs due to this resistance. Additionally, pressure drops can also happen at the point of use, particularly if the line is inadequately sized, which can significantly affect the performance of the equipment being powered.

When designing and maintaining a compressed air system, it is essential to take pressure measurements at various locations to detect and resolve potential issues before they escalate. The Compressed Air Challenge recommends specific points for regular pressure assessments to accurately gauge the operating pressure of your system.

  • Inlet to compressor (to monitor inlet air filter) vs. atmospheric pressure
  • Differential across air/lubricant separator
  • Inter-stage on multistage compressors
  • After-cooler
  • At treatment equipment (dryers, filters, etc.)
  • Various points across the distribution system
  • Check pressure differentials against manufacturers’ specifications. If high pressure drops are noticed, this indicates a need for service.

After taking the necessary measurements, you should sum the recorded pressure drops and subtract this total from your compressor’s operating range. The resulting value represents the actual operating pressure at the point of use.

If your distribution system is correctly sized and the pressure drops across your equipment are within acceptable limits, any pressure drop observed at the point of use suggests a lack of sufficient air volume. This issue may stem from restrictive fittings or inadequately sized air lines, hoses, or tubes. It is essential to ensure that the point of use product is installed in accordance with the manufacturer’s specifications for compressed air.

If you have questions about pressure drops, or anything regarding EXAIR and our products, please do not hesitate to reach out.

Jason Kirby
Application Engineer
Email: jasonkirby@exair.com
Twitter: @EXAIR_jk

Common Compressed Air Drawing Symbols

Published on by John BallLeave a comment
The symbols on top denote the EXAIR products below (left to right): Flowmeter, Pressure Gauge, and Solenoid Valve

When it comes to drawings and diagrams to map out a process system, the piping and instrumentation diagrams (P&ID) are a great way to situate and find components.  They use different symbols to represent the types of products, the layout of the system, installation, and process flow.  These standard symbols are created by ANSI or ISO.  They are used in electrical, hydraulic, and pneumatic processes. I will cover some pneumatic symbols and the process flow in this blog.

A colleague, Russ Bowman, wrote an article about “Knowing Your Symbols Is Key To Understanding Your Drawings”.  As a reference, air compressors are the start of your pneumatic system, and there are different types as represented by the symbols below.

Air compressors are considered the fourth utility in industries because they use so much electricity, and they are inefficient.  So, you need to use the compressed air as efficiently as possible.  As a typical pneumatic system, the air compressors, receiver tanks and compressed air dryers would be on the supply side.  The distribution system, or piping, connects the supply side to the demand side.  This symbol is represented by a simple line.  The demand side will have many different types of pneumatic devices.  Since there are so many, ANSI or ISO has created some common types of equipment.  But if there isn’t a symbol created to represent that part, the idea is to draw a basic shape and mark it.

From top left, and then down: Automatic Drain Filter Separator, Oil Removal Filter, Pressure Regulator, and Super Air Knife

As an example, if I were to do a P&ID diagram of the EXAIR Super Air Knife Kit, it would look like the above diagram.  The kit will include the Super Air Knife with an Automatic Drain Filter Separator and a Pressure Regulator.  The Filter Separator is a diamond shape and, since it has an Automatic Drain, a triangle is placed at the bottom.  Filter Separators are used to clean the compressed air and keep the Super Air Knife clean.  The Automatic Drain will discard water and oil from the filter bowl when it accumulates over the float.  The next item is the pressure regulator, which is represented by a rectangle with an adjustment knob to “dial in” the desired blowing force.  And at the end, we drew a rectangle, which represents a Super Air Knife, as marked.

Using the P&ID diagram for the process flow is important.  You noticed that the Filter Separator would come before the Pressure Regulator.  This is significant when installing this system.  Did you remember the statement above about “using your compressed air as efficiently as possible”?  Inefficiencies come from two basic areas; pressure drop and overusing your compressed air.  Pressure drop is based on velocity.  The lower the velocity, the lower the pressure drop.  For the second part about overusing compressed air, the Pressure Regulator will help.  You want to use the lowest amount of air pressure as possible for the Super Air Knife to “do the job”.  The lower air pressure will use less compressed air in your operation.

EXAIR products are engineered to be safe, efficient, and effective in your compressed air system.  If you need help to place them in your P&ID diagrams, an Application Engineer can help you.  It is important to have the pneumatic devices in the proper place.  If you want to efficiently use your compressed air, you can use EXAIR products for your blow-off devices.  We have been doing this for a long time.

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