## Replacing a 1/4″ Open Copper Tube With a 2″ Flat Super Air Nozzle Leads To Quick ROI

The generation of compressed air accounts for approximately 1/3 of all energy costs in an industrial facility and up to 30% of that compressed air is wasted through inefficient operation. Open pipes or homemade blowoffs waste a ton of compressed air, resulting in high operating costs. By replacing these devices with an energy efficient, engineered solution, you can reduce this waste and dramatically cut energy costs.

For example, let’s look at the average operating costs for a single 1/4″ open copper tube. (If you don’t know you current energy costs, a reasonable average to use is \$ 0.25 per every 1,000 SCF used, based on \$ 0.08/kWh.

A single 1/4″ open copper tube consumes 33 SCFM @ 80 PSIG and costs roughly \$ 0.50 per hour to operate. (33 SCF x 60 minutes x \$ 0.25 / 1,000 = \$ 0.50). For an 8 hour shift, the total cost would be \$ 4.00 (\$ 0.50 x 8 hours = \$ 4.00).

If we were to replace the 1/4″ open copper tube with our Model # 1122 2″ Flat Super Air Nozzle with 1/4″ FNPT inlet, the air consumption would be reduced to 21.8 SCFM @ 80 PSIG. This may not seem like much of an air usage reduction, but when you look at the monetary, total cost of ownership for purchasing and operating the nozzle, the savings can quickly add up.

The operating cost for a 2″ Flat Super Air Nozzle with 1/4″ FNPT inlet is \$ 0.33 per hour (21.8 SCF x 60 minutes x \$ 0.25 / 1,000 = \$ .033) or \$ 2.64 per 8 hour shift (\$ 0.33 x 8 hours = \$ 2.64).

We can now compare the operational cost between the 2 devices:

1/4″ open copper tube operating costs:
\$ 0.50 per hour
\$ 4.00 per day (8 hours)

2″ Flat Super Air Nozzle operating costs:
\$ 0.33 per hour
\$ 2.64 per day (8 hours)

Cost Savings:
\$ 4.00 / day (open copper tube) –  \$ 2.64 / day (2″ Flat Super Air Nozzle) = \$ 1.36 savings per day

The Model # 1122 2″ Flat Super Air Nozzle has a list price \$ 67.00 USD.

ROI or Return On Investment calculation:
\$ 67.00 (Cost) / \$ 1.36 (savings per day) = 49.26 days.

The 2″ Flat Super Air Nozzle would pay for itself in just over 49 days in operation. This is the savings for replacing just ONE 1/4″ open copper tube with an engineered solution! In most industrial plants, there could be several of these which presents even more opportunities to reduce the overall operational costs.

Our focus here at EXAIR is to improve the overall efficiency of industrial compressed air operating processes and point of use compressed air operated products. If you are looking to reduce compressed air usage in your facility, contact an application engineer and let us help you optimize your current system.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

## Fluidics, Boundary Layers, And Engineered Compressed Air Products

Fluidics is an interesting discipline of physics.  Air, in particular, can be made to behave quite peculiarly by flowing it across a solid surface.  Consider the EXAIR Standard and Full Flow Air Knives:

If you’ve ever used a leaf blower, or rolled down the car window while traveling at highway speed, you’re familiar with the power of a high velocity air flow.  Now consider that the Coanda effect can cause such a drastic redirection of this kind of air flow, and that’s a prime example of just how interesting the science of fluidics can be.

EXAIR Air Amplifiers, Air Wipes, and Super Air Nozzles also employ the Coanda effect to entrain air, and the Super Air Knife employs similar precision engineered surfaces to optimize entrainment, resulting in a 40:1 amplification ratio:

As fascinating as all that is, the entrainment of air that these products employ contributes to another principle of fluidics: the creation of a boundary layer.  In addition to the Coanda effect causing the fluid to follow the path of the surface it’s flowing past, the flow is also affected in direct proportion to its velocity, and inversely by its viscosity, in the formation of a boundary layer.

This laminar, lower velocity boundary layer travels with the primary air stream as it discharges from the EXAIR products shown above.  In addition to amplifying the total developed flow, it also serves to attenuate the sound level of the higher velocity primary air stream.  This makes EXAIR Intelligent Compressed Air Products not only as efficient as possible in regard to their use of compressed air, but as quiet as possible as well.

If you’d like to find out more about how the science behind our products can improve your air consumption, give me a call.

## Protect Personnel from Noise with Engineered Products

Sound can be defined as vibrations that typically travel as an audible wave through mediums that can be a gas, liquid or solid. For this blog we will concern ourselves with sound travelling through a gas (atmosphere) in an industrial setting.

Sound is energy that travels in waves and is measured by its frequency (cycles per second) and amplitude (intensity). A common unit of measurement for sound energy is the decibel. The decibel (abbreviated with dBA) is a unit-less number that is based on the logarithm of a known measured quantity to a reference quantity. Without reciting the equation for every increase of 3 dBA is a doubling of sound energy or twice as loud.

Since our focus is on industrial sound one might question why be concerned at all, after all sound emanates from most machines and devices. The reason for concern is that there are OSHA regulations regarding the amount of time workers can be exposed to different levels of sound in their workday as illustrated below. These limits are in place to protect personnel from Noise Induced Hearing Loss or NIHL. When the damage to anyones hearing is caused by their profession, it is also referred to as Occupational Hearing Loss or OHL.

After monitoring for noise, NIOSH and the CDC next recommend administrative controls to minimize or eliminate the noise hazard (click for their helpful PDF). This would include the use of noise reducing EXAIR products like Super Air Nozzles, Air Knives and Air Amplifiers.

When considering the many items in an industrial setting that produce loud sounds the list would be exhaustive. Many of them simply produce loud sounds that can’t be eliminated or reduced while on the other hand there are some that can. Some of the noisiest offenders that plants have control over are air powered tools and open tube blow-offs.  Eliminating inefficient methods of part blow off & part cleaning with an engineered solution allows a company to significantly reduce the level of sound in their plant, improve worker safety and save money on compressed air consumption.

Employers are required to provide hearing protection to employees whom are exposed to sounds above 90 dBA on a Time Weighted Average (TWA). Without digressing into the formulas TWA calculates a workers daily exposure to occupational sounds by taking into account the average levels (in dBA) and the time exposed to different levels.  This is the how OSHA assesses workers exposure and what steps should be taken to protect the workers.

To conclude, plants need to be mindful of the OSHA regulations for sound levels, time of exposure and that hearing protectors wear out. Earmuff seals can lose their elasticity and reduce their effectiveness and the soft pre-molded earplugs can wear out in a day and need replaced.  Keep a good supply on hand and OSHA suggests letting workers with noisy hobbies take them home for protection off the clock!

If you would like to discuss reducing noise or any EXAIR product, I would enjoy hearing from you…give me a call.

Steve Harrison
Application Engineer

Send me an email
Find us on the Web

## The Case Is Mounting For Stay Set Hoses

So, you’ve selected a quiet, efficient, and safe EXAIR Super Air Nozzle for your blow off application – good call! – and now you’re thinking about how to install it.  Sometimes, it’s as simple as replacing whatever you’re using right now:

Or maybe you’re using an open end blow off…in which case, you’re just an adapter away:

Perhaps, though, it’s a new installation, or the existing supply lines aren’t suitable for one reason or another.  In those cases, we’ve still got you covered…consider the EXAIR Stay Set Hose:

Available in a variety of lengths from 6″ to 36″, they’re positionable, and re-positionable with a simple bending action.  They won’t kink or easily fatigue like copper tubing.  The supply end is 1/4  MNPT, and you have your choice of 1/4 MNPT or 1/8 FNPT on the other end, depending on which Super Air Nozzle, Air Jet you need to use it with.

We also offer Blow Off Systems, which are a combination of a specific Air Nozzle (or Air Jet,) fitted to a Stay Set Hose:

For added convenience and ease of installation, these products can also come with a Magnetic Base:

Stay Set Hoses are also available with a variety of our Soft Grip Safety Air Guns, and they make the GEN4 Stay Set Ion Air Jet one of our most popular Static Eliminator products.  They’ve even been successfully applied with small Air Amplifiers and Air Knives…with certain limitations (spoiler alert: trying this with a 108″ Super Air Knife is going to be a definite “no.”)

From the beginning in 1983, EXAIR’s focus has been on being easy to do business with, and that goes from our friendly customer service to our expert technical support to our 99.9% on-time shipments (22 years and running) to designing our engineered products and value-added accessories with efficiency, safety, and ease of installation in mind.  If you want to find out more, give me a call.

## EXAIR Provides Quick Blowoff Solution for Gauge Manufacturer

I was recently contacted by a manufacturer of custom measurement systems. They were working on a design for a system that could measure (2) different sizes of gears with a high degree of accuracy. A robotic arm would pick up the gear off of a conveyor and deposit it onto a gauge for inspection.

During the initial quoting phase of the project they had been a little misled. They were told that the gears would be completely clean and free of debris before being deposited on the conveyor and picked up for inspection.  It turns out this would not be the case. Chips, oil, or debris remaining on the gear would result in false part rejection. With the required completion date looming, they reached out to EXAIR for some help in implementing a solution to clean the gear before inspection.

While blowing off the oil or chips from the gear was the primary concern, having this debris flying around inside the machine could have been problematic as well. We needed to find a way to contain the chips and remove them. In the process, there was a brief moment that the robot arm held the gauge in place just prior to depositing it onto the gauge. It was there that we identified an opportunity to both clean and remove the chips that were blown off the gear. Using a Model 1105 3/8 NPT Super Air Nozzle and Model 9068 Swivel, they were able to precisely position the blowoff to hit across the bottom of the gear where the chips were located. They then 3D printed a shroud to contain the area where the gauge was held and the blowoff would be performed. They designed the shroud with a 1-1/4” outlet to connect directly to our Model 6082 Line Vac. The intake of the Line Vac was installed right at this point and was set to activate as soon as the air nozzles began their cleaning cycle. The chips were blown off of the gears, contained by the shroud, and taken away to a bin underneath the machine by the Line Vac. The crisis was averted!!

This was the first time they had implemented some type of method to clean the part before measuring. In the past, they had lost potential projects due to the inability for them to provide a clean part for measurement. With this newfound method of part cleaning, they’re now able to be a more complete solutions provider to their customers. They’re able to design the part cleaning feature into the process from the start, rather than retroactively as they had to do here.

At EXAIR, we understand how problems can crop up during design and cause potential delays in the completion of a project. For this reason, we keep all of our catalog products in stock and ship same day with an order placed by 3:00 pm EST. This customer was local and was able to call in with a problem, determine a solution, and come pick up their order the same day. If you are having difficulty cleaning or drying machined parts, give us a call. EXAIR has the solution, in stock, ready to ship to you immediately.

Tyler Daniel
Application Engineer
E-mail: TylerDaniel@exair.com

My colleague, Russ Bowman, wrote a blog about “Sound Power Level and Sound Pressure”.  He discussed the logarithmic equations around sound.  I will be discussing what happens when you have more than one sound source, as often heard within manufacturing plants.  Sounds can be added together to determine the overall sound level that your hear.  This is very important when it comes to minimizing hearing loss.

In looking at a single source of sound, sound pressure is created by the loudness of a noise.  The units are measured in Pascals.  The lowest pressure perceived by human hearing is 0.00002 Pa, and we can use this value as a reference point.  From sound pressures, we can arrive to a sound pressure level which is measured in decibel, dB.  This correlation between sound pressures and sound pressure levels are calculated by Equation 1:

L – Sound Pressure Level, dB

P – Sound pressure, Pa

Pref – reference sound pressure, 0.00002 Pa

As an example, the sound pressure from a passenger car as heard from the roadside is 0.1 Pa.  With Equation 1, we can get the following decibel level:

L = 20 * Log10 (0.1Pa/0.00002Pa) = 74 dB

Because human ears are sensitive to different frequencies, the sound pressure levels can be modified, or weighted, to indicate an effective loudness level for humans.  This adjustment is done in two different ways; A-weighting and C-weighting.  The C-weighting is for very loud noises with high peaks or sharp impacts like gunfire. The A-weighting is the most commonly used value as the sound pressure levels are adjusted by the frequency level.  For higher and lower frequencies, the change in the sound value is much greater than the mid-level frequencies that are within our hearing range.  Sound measurements for safety are measured in the A-weighted scale.  OSHA created a chart in the 29CFR-1910.95(a) standard that shows the noise levels over exposure times for an operator.  To use the OSHA chart accurately, the total noise level in dBA should be calculated.

To determine the total sound level, we can add all the sound pressure levels together by Equation 2:

Where L1, L2… represents the sound pressure level in dBA for each sound source.

As an example, a manufacturing plant had an operator using a machine that had four copper tubes to blow off a cutting operation (reference photo below).

The decibel level for a copper tube was measured at 98 dBA.  The total amount of sound that the operator was exposed to was determined by Equation 2 with four values.

L = 10 * log10 (109.8 + 109.8 + 109.8 + 109.8)

L = 104 dBA

In looking at the OSHA chart, the operator would only be allowed to operate the machine only a little over one hour without hearing protection.  In this same example, we replaced the copper tubes with an EXAIR Super Air Nozzle, model 1110SS.  The noise level for each nozzle is 74 dBA.  By replacing all four copper tubes with Super Air Nozzles, Equation 2 becomes:

L = 10 * log10 (107.4 + 107.4+ 107.4 + 107.4)

L = 80 dBA

The total sound level is now in accordance with OSHA regulations for the operator to work all 8 hours at the machine without hearing protection.

A commonly used acronym in hearing safety is NIHL, or Noise Induced Hearing Loss.  To keep your operators safe and reduce NIHL, it is important to measure the total sound level.  As a protocol in safety, it is a requirement to use engineering standards before purchasing personal protective equipment or PPE.  For the customer above, they followed that protocol with our Super Air Nozzles.  If you need to reduce noise levels in your facility by engineering standards, EXAIR offers a large line of blow-off products that can meet the safety requirements.

John Ball
Application Engineer
Email: johnball@exair.com

## People of Interest: Daniel Bernoulli – 2/8/1700 to 3/17/1782

Daniel Bernoulli was born in Groningen, Netherlands on February 8, 1700  and was part of a large family heritage of famous mathematicians – His father Johann Bernoulli, one of the first founders of calculus, his uncle Jacob Bernoulli and his older brother Nicolous. When he was only 7 years old, Daniel began to take an interest in mathematics but his father convinced him that there was no financial gain to be had in mathematics and recommended he focus his studies in business instead. Reluctant at first, Daniel would take his father’s advice under the one condition, that his father would tutor him in calculus and his theories of kinetic energy.

At 13 years old, Daniel attended Basel University where he studied logic and philosophy completing his bachelor’s degree by the age of 15 and earning his master’s degree just 1 year later. Over the years, Daniel’s relationship with his father was strained as a result of him plagiarizing his father’s findings. Eventually, his father passed without reconciling with Daniel. At 24, Daniel became a Professor of Mathematics  at a University in Venice but resigned from the position just 9 years later in 1733.

His most recognized mathematical contribution, Bernoulli’s principle, came in 1938 while performing energy conservation experiments, and he published the results in his book entitled Hydrodynamica . He discovered that when fluid travels through a wide pipe into a smaller, more narrow pipe, the fluid begins to move  faster. He determined that the volume or amount of fluid moving through the pipe remains unchanged but will conform to the shape of the pipe or container as it flows. He concluded that the higher the pressure, the slower the flow of the liquid and the lower the pressure, the faster the liquid flow.

The same principle can be applied to air. As air moves around an obstruction or object, it follows the profile of the part and begins to speed up.

Take for example our Super Air Nozzles. The compressed air exits the nozzle through a series of jets which induces a low pressure around the profile of the nozzle, drawing in ambient air. This entrainment of air, up to 25 times or more, results in a high outlet flow at minimal compressed air consumption.

Many of the products offered by EXAIR incorporate this science which can lead to a more efficient operation by lowering compressed air demand ultimately reducing operating costs. To see how our products can help you save money while increasing process performance, contact an Application Engineer for assistance.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

Bildnis des Daniel Bernoullius image courtesy of Universitätsbibliothek Leipzig via creative commons license