Tag: digital flowmeter

RoHS, EXAIR, And You

Published on by Russ BowmanLeave a comment

The 20th century was an amazing time for technological advances. In just 70 years, the science & engineering communities went from believing that powered flight was impossible, to actually powering a flight that took three astronauts all the way to the Moon…and back. In the 50 years or so since then, the computers with the power required for space travel went from needing a whole room, to being able to fit on our desks, and eventually, our pockets.

All three of these: a state of the art computer from 1962 (left), the desktop computer I’m writing this blog on (middle), and a smart phone being used for its most popular function (right) all have about the same amount of computing power, believe it or not. (full disclosure: I believe it because I used my smart phone to look that up on the internet)

Along with these amazing advances in technology came exponential increases in the materials it takes to make devices like desktop (or laptop) computers and smart phones…and some of those materials don’t get along well at all with the environment, and by extension, those of us who live in said environment. This doesn’t normally matter as long as those materials are housed inside an operating computer or cell phone (or myriad other electronic devices), but it DOES become a concern when they’re disposed of. When stuff like that ends up in landfills, for instance, it has a bad habit of making its way into the water table…and that’s not good for anyone.

In 2002, the European Union (EU) started pursuing legislation to restrict the use of certain hazardous substances, to get out ahead of disposal issues by keeping them out of products from the very beginning. This led to the creation & implementation of the RoHS Directive. It’s been revised, amended, and updated over the years, because it turns out there are no viable substitutes for SOME of those substances in SOME situations. Among these exceptions:

  • Mercury is used extensively in a number of energy efficient CFL light bulbs and fluorescent tubes, so there are exemptions for that, and it works because there’s a whole industry devoted to the proper recycling of these products.
  • My personal favorite is the specific exclusion for lead in the manufacture of pipe organs. Seems that the lead based alloy that’s been used for centuries is critical to the tonal qualities of the sound that the pipes produce. Since disposal rates of these are negligible (the use of this alloy is one of the reasons they LAST for centuries), pipe organ pipes don’t have to be RoHS compliant.

Compliance with the RoHS Directive is so important to EXAIR, it’s part of our Sustainability Plan. All of our products that are subject to the Directive have certificates of compliance (available upon request) that document their compliance. Per the specifics of the Directive, these are comprised of certain products in our Optimization, Static Eliminators, and Cabinet Cooler System product lines:

  • Optimization:
    • EFC Electronic Flow Control Systems
    • Digital Flowmeters
    • Digital Sound Level Meters
    • Ultrasonic Leak Detectors
  • Static Eliminators:
    • Super Ion Air Knives
    • Standard Ion Air Knives
    • Ionizing Bars
    • Super Ion Air Wipes
    • Ion Air Cannons
    • Ion Air Guns
    • Ion Air Jets
    • Power Supplies
    • Intellistat Ion Air Guns
    • Intellistat Ion Air Nozzles
    • Static Meters
  • Cabinet Cooler System products:
    • Electronic Temperature Control Systems
    • Thermostats & Capacitors
    • Solenoid Valves

These are all of our products that are electrical or electronic in nature. Our broad line of engineered compressed air products are not subject to the Directive, as they have no electrical or electronic components. We DO make sure these comply with other regulatory directives, as applicable, such as:

  • Conflict Mineral Free: All compressed air products
  • CE: All products
  • UL: Static Eliminators and Cabinet Cooler Systems are UL Listed, HazLoc Cabinet Cooler Systems are UL Classified
  • ATEX: These are a brand new line (as of this writing) of Cabinet Cooler products

If you’d like to find out more about EXAIR’s commitment to compliance with any of these standards or directives, give me a call.

Russ Bowman, CCASS

Application Engineer
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Compressed Air Efficiency! “Step One”

Published on by Jordan T ShouseLeave a comment

I’m currently in the closing process of selling my first home. This is the house I got married in, brought my first child home to. Needless to say there has been a lot going on to get the place up to selling shape, one of those things was getting the HVAC system checked out to verify its running correctly and efficiently! (Spoiler, mine was running very well thank goodness)

With compressed air being considered a fourth utility its important we check the efficiency of the system and fix issues and install upgrades where we can! EXAIR has six simple steps to optimize your compressed air system. Following these steps will help you to cut electrical costs, reduce overhead, and improve your bottom line. In this blog, I will cover the first step – Measure the air consumption to find sources that use a lot of compressed air.

EXAIR Six Steps To Optimizing Your Compressed Air System

Data is important to have when diagnosing wasteful and problematic areas within your compressed air system. To measure air consumption, flow meters are used to find the volume or mass of compressed air per unit of time. Flow rates are very useful data points to find problems like leaks, over-use in blow-offs, waste calculations, and comparison analysis.

The first step to optimizing compressed air systems within an industrial facility is to get a known baseline. To do so, utilizing a digital flowmeter is an ideal solution that will easily install onto a hard pipe that will give live readouts of the compressed air usage for the line it is installed on.  There is also an additional feature that we offer on the Digital Flowmeters that can help further the understanding of the compressed air demands within a facility.

The Pressure Sensing Digital Flowmeters are available from 2″ Sched. 40 Iron Pipe up to 8″ Sched. 40 Iron Pipe.  As well as 2″ to 4″ Copper pipe.  These will read out and with the additional Data Logger or Wireless Capability options record the information. When coupled with the wireless capability an alarm can be set for pressure drops that give live updates on the system as well as permits data review to see system trends throughout the day.

Generating a pressure and consumption profile of a system can help to pinpoint energy wasters such as timer-based drains that are dumping every hour versus level based drains that only open when needed. A scenario similar to this was the cause of an entire production line shut down nearly every day of the week for a local facility until they installed flowmeters and were able to narrow the demand location down to a filter bag house with a faulty control for the cleaning cycle.

If you would like to discuss the best digital flowmeter for your system and to better understand the benefits of pressure sensing, please contact us.

Jordan Shouse
Application Engineer

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Fluid Mechanics – Boundary Layer

Published on by johnball2014Leave a comment

Fluid mechanics is the field that studies the properties of fluids in various states.  Fluid dynamics studies the forces on a liquid or a gas during motion.  Osborne Reynolds, an Irish innovator, popularized this dynamic with a dimensionless number, Re.  This number determines the state in which the fluid is moving; laminar, transitional, or turbulent.  For compressed air, a value of Re < 2300 will indicate a laminar air flow while the value of Re > 4000 will be in the range of turbulent flow.  Equation 1 below shows the relationship between the inertial forces of the fluid as compared to the viscous forces.

Equation 1:

Re = V * Dh / u

Re – Reynolds Number (no dimensions)

V – Velocity (feet/sec or meters/sec)

Dh – hydraulic diameter (feet or meters)

u – Kinematic Viscosity (feet^2/sec or meter^2/sec)

To dive deeper into the fluid dynamics, we can examine the layer which is next to the surface; the boundary layer.  This could refer to a wing on an airplane, a blade in a turbine, or inside compressed air lines.  In this blog, I will target the boundary layer inside pipes, tubes, and hoses that are used to transport compressed air.  The profile across the area (reference diagram below) is a velocity gradient.  The boundary layer is the distance from the wall or surface to 99% of the maximum velocity of the fluid stream.  At the surface, the velocity of the fluid is zero because the fluid is in a “no slip” condition.  As you move away from the wall, the velocity starts to increase.  The boundary layer thickness measures that area where the velocity is not uniform.  If you reach 99% of the maximum velocity very close to the wall of the pipe, the air flow is turbulent.  If the boundary layer reaches the radius of the pipe, then the velocity is fully developed, or laminar.  Mathematically, laminar flow can be calculated, but turbulent flow requires theories and experimental data to determine. 

As an analogy, imagine an expressway as the velocity profile, and the on-ramp as the boundary layer.  If the on-ramp is long and smooth, a car can reach the speed of traffic and merge without disrupting the flow.  This would be considered Laminar Flow.  Now imagine an on-ramp to be perpendicular to the expressway. As the car goes to merge into traffic, it will cause chaos and accidents.  This is what I would consider to be turbulent flow.     

In a compressed air system, similar things happen within the piping scheme.  Valves, tees, elbows, pipe reducers, filters, etc. are common items that will disrupt the flow.  Let’s look at a scenario with the EXAIR Digital Flowmeters.  In the instruction manual, we require the meter to be placed 30 pipe diameters from any disruptions.  The reason is to get a laminar air flow for accurate flow measurements.  In order to get laminar flow, we need the boundary layer thickness to reach the radius of the pipe where 99% of the air speed is represented at the center. 

Why is this important to know?  In many compressed air applications, the laminar region is the best flow to generate a strong force; efficiently and quietly.  Allowing the compressed air to have a more uniform boundary layer will optimize your compressed air system.  And for the Digital Flowmeter, it helps to measure the flow accurately and consistently.  If you would like to discuss further how to reduce “traffic jams” in your process, an EXAIR Application Engineer will be happy to help you.

John Ball
Application Engineer
Email: johnball@exair.com

Twitter: @EXAIR_jb

Photo: Smoke by Skitterphoto.  Pixabay license

Compressed Air Digital Flow Meters Monitor Your System Demand

Published on by bdwagesLeave a comment

In the times we live in, efficiency is key. To offset the rising costs of goods, services, and energy we must be purposeful in lowering costs wherever we can. Every company has large utility expenses such as electricity, water, gas, sewer, waste, and recycling. Many companies have policies and systems in place to help control these expenses. One major utility that gets overlooked is your compressed air. Many companies just loop this expense into the gas and or electricity funnel and move on. But that can be a costly mistake. Assuming you utilize compressed air in your facility, it is most likely your 3rd-4th highest utility expense. The good news is there are many ways to make this utility much more efficient.

We have several EXAIR blogs on how to improve your compressed air efficiency from mitigating leaks, sizing pipe properly, flow control, pressure regulators, engineered nozzles and tools, and even receiver tanks. These are all very effective ways to reduce this expense. There is another tool that I would like to share with you; our Digital Flow Meters. What they are, how they work, and how they can save you money…

With a rough cost of $0.25 per 1000 SCFM, wouldn’t it be nice to know how many SCFM you are using? (Please click here for a great blog on how to calculate your SCFM cost) More importantly how much air are you wasting… Your compressor information already tells you how much air it is producing and with EXAIR’s Digital Flowmeter, you will know the exact amount of compressed air that is being used, making it very easy to identify loss. These losses are primarily found in leaks or inefficient air products. A best practice is to install one of these on each leg of the air distribution system and monitor and and benchmark the compressed air usage.

EXAIR Digital Flowmeter

The EXAIR Flowmeters work by measuring the temperature differential between two probes that are inserted into the compressed air pipes. One probe is kept warmer than the other, and the mass flow rate is determined by the amount of heat required to maintain the temperature differential. The flow rate, or SCFM is displayed on the large digital display

To install the Flowmeters, you will drill 2 holes into your pipe for the probes. Included with the meter is the drill bit and the Drill Guide to quickly install the meter. We have these available in many sizes from 1/2″ to 4″ iron pipe, We also offer these for Copper Pipes, and can make / calibrate them for many others, we will just need the information.

In addition to our standard version we offer several upgrades. One is a Data Logging version. You can download our software and then set the data logging to record from once a second for about 9 hours of data to twice a day for over 2 years worth of data. You simply plug the Data Log Stick this into your computer, download and repeat.

We also offer a wireless option that will run through a ZigBee mesh Network. A radio module within each meter transmits data to an ethernet connected gateway. You can also piggyback meter to meter to extend the range for this wireless solution. Each meter has a range of about 100 feet.

Many people ask if they have to shut down their system to install the Flowmeters. Understanding that this could cause systemic issues, we have a Hot Tap option that will allow you to install while the pipe is still under pressure. It incorporates 2 valves that the probes pass through as well as a muffler that collects the chips from the drilling process. This is only available on the 2″ or larger units.

Speaking of pressure, we also offer a Pressure Sensing Digital flow meter. On this, there is a pressure sensor that is mounted between the two flow sensor probes. The pressure is sent via a second milliamp output. The display can be configured to show either pressure or flow. You can set this to send alarms if the pressure falls under 50 psi. Also only available on 2″ pipes and above.

Finally, we also offer Block Off Rings. These are simply rings to block off holes where the flowmeter was, in case you need to use the same one in a different location.

Please fee free to reach out with any questions, or for more information. Let us help you save air and money…

Thank you for stopping by,

Brian Wages

Application Engineer

EXAIR Corporation
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