Receiver Tank Calculations

Receiver Tank

My colleague, Lee Evans, wrote a blog about calculating the size of receiver tanks within a compressor air system.  (You can read it here: Receiver Tank Principle and Calculations).  But, what if you want to use them in remote areas or in emergency cases?  During these situations, the air compressor is not putting any additional compressed air into the tank.  But, we still have potential energy stored inside the tanks similar to a capacitor that has stored voltage in an electrical system.  In this blog, I will show how you can calculate the size of receiver tanks for applications that are remote or for emergency systems.

From Lee Evans’ blog, Equation 1 can be adjusted to remove the input capacity from an air compressor.  This value is Cap below.  During air compressor shutdowns or after being filled and removed, this value becomes zero.

Receiver tank capacity formula (Equation 1)

V = T * (C – Cap) * (Pa) / (P1-P2)

V – Volume of receiver tank (cubic feet)

T – Time interval (minutes)

C – Air requirement of demand (cubic feet per minute)

Cap – Compressor capacity (cubic feet per minute)

Pa – Absolute atmospheric pressure (PSIA)

P1 – Tank pressure (PSIG)

P2 = minimum tank pressure (PSIG)

 

Making Cap = 0, the new equation for this type of receiver tank now becomes Equation 2.

Receiver tank capacity formula (Equation 2)

V = T * C * (Pa) / (P1-P2)

With Equation 2, we can calculate the required volume of a receiver tank after it has been pre-charged.  For example, EXAIR created a special Air Amplifier to remove toxic fumes from an oven.  The Air Amplifier was positioned in the exhaust stack and would only operate during power failures.  In this situation, product was being baked in an oven.  The material had toxic chemicals that had to cross-link to harden.  If the power would go out, then the product in the oven would be discarded, but the toxic fumes had to be removed.  What also doesn’t work during power outages is the air compressor.  So, they needed to have a receiver tank with enough volume to store compressed air.  From the volume of the oven, we calculated that they need the special Air Amplifier to operate for 6 minutes.  The compressed air system was operating at 110 PSIG, and the Air Amplifier required an average air flow of 10 cubic feet per minute from the range of 110 PSIG to 0 PSIG.  We are able to calculate the required receiver volume to ensure that the toxic fumes are evacuated from the oven in Equation 2.

Receiver tank capacity formula (Equation 2)

V = T * C * Pa / (P1 – P2)

V = 6 minutes * 10 cubic feet per minute * 14.7 PSIA / (110 PSIG – 0 PSIG)

V = 8 cubic feet.

Receiver tanks are more commonly sized in gallons.  In converting 8 cubic feet to gallons, we get a 60-Gallon Receiver Tank.  EXAIR recommended the model 9500-60 to be used near the oven to operate the special Air Amplifier during power outage.

Another way to look at Equation 2 is to create a timing equation.  If the volume of the tank is known, we can calculate how long a system will last.  In this example for scuba diving, we can use this information to configure the amount of time that a tank will last.  The diver has a 0.39 cubic feet tank at a pressure of 3,000 PSIG.  I will use a standard Surface Consumption Rate, SCR, at 0.8 cubic feet per minute.  If we stop the test when the tank reaches a pressure of 1,000 PSIG, we can calculate the time by using Equation 3.

Receiver tank timing formula (Equation 3):

T = V * (P1 – P2) / (C * Pa)

T – Time interval (minutes)

V – Volume of receiver tank (cubic feet)

C – Air demand (cubic feet per minute)

Pa – Absolute atmospheric pressure (PSIA)

P1 – Initial tank pressure (PSIG)

P2 – Ending tank pressure (PSIG)

By placing the values in the Equation 3, we can calculate the time to go from 3,000 PSIG to 1,000 PSIG by breathing normal at the surface.

T = 0.39 cubic feet * (3,000 PSIG – 1,000 PSIG) / (0.8 cubic feet per minute * 14.7 PSIA)

T = 66 minutes.

What happens if the diver goes into deeper water?  The atmospheric pressure, Pa, changes.  If the diver goes to 100 feet below the surface, this is roughly 3 atmospheres or (3 * 14.7) = 44.1 PSIA.  If we use the same conditions above except at 100 feet below, the time will change by a third, or in looking at Equation 3:

T = 0.39 cubic feet * (3,000 PSIG – 1,000 PSIG) / (0.8 cubic feet per minute * 44.1 PSIA)

T = 22 minutes. 

If you have any questions about using a receiver tank in your application, you can contact an EXAIR Application Engineer.  We will be happy to solve for the proper volume or time needed for your application.

 

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

EXAIR Cabinet Coolers for a Food and Beverage Company

316SS Electrical Panels

A food and beverage company had 316SS NEMA 4X (IP66) electrical panels inside their facility.  The reason for the stainless-steel construction and NEMA 4X or IP66 rating was for the periodic washdowns with an aggressive cleaner.

This particular company had a bottling process and inside each panel, sensitive electrical components would control the operation of the system.  The panels were fitted with Freon type air conditioners to keep the electrical components cool.  One day, they had an A/C unit that failed, and it shut down their system for half a day.  For a bottling company, a shutdown for this long stopped many bottles from being processed which costed much money from loss of production.

They had four panels that were setup similar right next to each other.  They were fitted with 1,700 BTU/hr freon system on each panel.  In this situation, one of the refrigerant compressors failed.  They had to hire a mechanical serviceman with a license to work on Freon systems.  Because of the length of time to get their system restarted, they were losing money every minute.  This emergency call really hindered the entire bottling process.  In fear of another shutdown, they contacted EXAIR to see if we could help them.

Even with constant maintenance, the life span of a Freon system is only around five years.  (It can be even shorter if preventative maintenance is not scheduled regularly). Any mechanical system with moving parts will wear out and fail.  EXAIR Cabinet Coolers use the power of a Vortex Tube which only needs compressed air to generate cold air.  With no moving parts to wear or unsafe Freon to leak, they are designed to keep your electrical components cool and operating for a very long time.  Trying to predict failures with refrigerant systems is very difficult to determine; but, with the EXAIR Cabinet Cooler Systems, it takes that worry away.

EXAIR NEMA Type 4X Cabinet Cooler System

EXAIR Cabinet Cooler Systems are manufactured in a variety of options and types to meet different application requirements.  For the food and beverage company above, I recommended the model 4830SS-316 Cabinet Cooler System to replace each of the A/C refrigeration systems.  The model 4830SS-316 would meet the cooling requirement with 2,000 BTU/hr capacity, the NEMA 4X (IP66) rating of the panel, and the 316SS construction to withstand washdowns.  The complete system includes the Cabinet Cooler, a filter, cold air distribution kit, a thermostat and a solenoid valve.  The thermostat is preset at 95 deg. F (35 deg. C), and it operates a solenoid valve to only turn on when cooling is needed.  EXAIR has this model in stock as well as many others for quick delivery, reducing any downtime.  After the installation of the Cabinet Coolers onto the panels, the worry of production stoppage due to a failure with an A/C system was alleviated.

Maintenance departments have many concerns in keeping a system running smoothly and uninterrupted.  Why add additional worries with coolant based panel coolers?  If you have electrical panels that can stop your operation like the bottling company above, an EXAIR Cabinet Cooler will be a reliable solution.  You can fill out the Cabinet Cooler Sizing Guide and an Application Engineer can determine the best model for you.

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

Super Air Nozzles; Rebates, Environmental Protection, and Energy Savings.

Family of Nozzles

Recently, I wrote a blog, “Flat Super Air Nozzles: Build Your Own System Overview”.  It described how the Flat Super Air Nozzles could be used singly or joined together with accessories for flexibility in your application.  In addition, it demonstrated the amount of compressed air savings and reduction in energy consumption to save you money.  Tyler Daniel, a colleague, wrote a similar blog on “ROI – Is it Worth the Investment?”  He explains the quick payback or ROI (Return on Investment) by using EXAIR Super Air Knives.  In both posts, the word “Super” is intertwined with the product name.  To expand a bit further, the word, “Super” is more than just a word.  It is about cost savings, efficiency, and energy conservation.   In this post, I will dive a bit more into the reasons why EXAIR uses the word, “Super”, and how it can help you.

When EXAIR started to manufacture compressed air products, we created a culture in making high quality products that are safe, effective, and efficient.  Being leaders in this industry, we created a program, the Efficiency Lab, to compare blow-off devices with EXAIR products in noise levels, flow requirements, and force measurements.  With calibrated test equipment, we compare the data in a qualified report to share with our customers.  This information can be helpful to determine the total amount of air savings and safety improvements that EXAIR products can offer.

With the total amount of energy savings that the EXAIR products can provide, EXAIR was able to partner with Energy Star and the Environmental Protection Agency.  This commitment by EXAIR for reducing energy to protect the environment for future generations is a cornerstone for our business model.  Compressors use electricity to produce compressed air.  In most industries, they consider compressed air as a fourth utility.  If you have pneumatics in your facility wouldn’t it be best to use it, and the electricity it requires, as efficiently as you can?

In conjunction with the Efficiency Lab, we created a Cost Savings Calculator.  It is a quick way to view payback periods and annual savings when using EXAIR products.  As an example, I used a 1” Flat Super Air Nozzle, model 1126, and compared it to a 1/8” open pipe.  (The reason behind the comparison is that the model 1126 can screw onto the end of the 1/8” NPT pipe.)  With an operation of 24 hours/day for 250 days a year, the amount of air used by an 1/8” open pipe is near 70 SCFM (1,981 SLPM) at 80 PSIG (5.5 Bar).  The model 1126 has an air consumption of 10.5 SCFM (297 SLPM) at 80 PSIG (5.5 Bar).  By putting the information in the Cost Savings Calculator, it determined that the ROI was in 2.1 days.  The annual savings was $5,355 per year.  Imagine if you replaced ten blow-off spots in your facility, the amount of money that could be saved.  Here is the worksheet below:

Why did I bring this up?  Besides showing the “hidden” extra cost that is wasted when using sub-standard blow-off devices, it also shows the amount of compressed air that was saved.  By using the model 1126, we were able to save 21,420,000 cubic feet of air per year (596,043 cubic meters of air per year).  With this amount of energy savings, people take notice.

The people that did take notice were the utility companies that make electricity.  Depending on your location, electrical suppliers initiated a rebate program to use engineered nozzles in your facility.  Similar to other energy saving rebates, like LED lightbulbs and high efficiency furnaces, the electrical providers notice a big savings when using EXAIR products.  If you qualify, the total cost to purchase and implement the EXAIR Super Air Nozzles are reduced.  (Even if a rebate program has not been implemented in your area, the idea of saving energy and compressed air makes it very profitable and environmentally sound in changing over to EXAIR products).  The website is DSIRE.  “DSIRE is the most comprehensive source of information on incentives and policies that support renewables and energy efficiency in the United States.”  Check it out to see if your area has instituted a rebate program.

When EXAIR uses the word “Super”, it is much more than just an adjective.  It shows the quality and precision that EXAIR uses in manufacturing our products, and the amount of cost and energy savings that can be generated.  Being backed by Energy Star, EPA, and rebate programs, EXAIR can help companies to upgrade their pneumatic systems.  Together, we can save energy, improve the environment, and reduce compressed air.  If you would like to discuss how EXAIR can work for you, you can contact an EXAIR Application Engineer to see if we can put the word, “Super”, into your compressed air program.

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

How a Super Air Knife Helps with Metal Etching

Etching Machine

A company had a process where they were etching metal components with an acid bath.  The system consisted of four baths where the metal parts would be dipped.  The four baths consisted of a wash, rinse, acid bath, and rinse again.  The automated system was contained inside an enclosed booth; and, once the parts were placed inside a 24” (610mm) X 18” (457mm) basket, a sliding door was closed to initiate the operation.  The timing sequence consisted of the basket being dipped into each bath for a certain length of time.  Between each bath cycle, the basket would be raised above the solution, and an open pipe blow-off would remove excess liquid from the part with compressed air.   They complained that the parts were not getting dry enough, and cross-contamination was causing process problems.  The acid bath was becoming more neutral and the effectiveness of the etching was being sacrificed.  The rinse water was becoming more “soapy” after the cleaning bath and more acidic after the acid bath.  Overall, they had to replace every one of the bath solutions which caused shut-downs and extra expense.

From similar applications, I was able to recommend a great solution.  Because of the acidic solution and corrosive environment, I recommended two stainless steel Super Air Knives, model 110024SS.  They are manufactured in 303 stainless steel.  EXAIR also offers 316 stainless steel as well as PVDF for more acidic or caustic etching.  Instead of using the open pipes to blow off the parts, the customer could replace them with the Super Air Knives.  They can easily be mounted above the front and back of the basket, blowing at a downward angle toward the dip tank.  The two Super Air Knives would remove the liquid solution from the parts as well as the basket to put back into the same dipping tank.  The more solution that is removed, the less liquid that will transfer from one solution to the next; thus, reducing cross-contamination dramatically.

After installing the model 110024SS Super Air Knives in their system, they started to see a vast improvement in their etching process.  The etching acid was able to be used roughly 40% longer as compared to the prior method.  As an added feature, the Super Air Knives decreased the time to blow off the parts as they can be adjusted for optimum cleaning.  Less waste and faster production times were how the EXAIR Super Air Knives helped the customer above.  If you have a similar application and want to discuss how we can improve your dipping process, please speak to one of our Application Engineers.  We’ll be happy to help.

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

Flat Super Air Nozzle: Build Your Own System Overview

Flat Nozzle Blow-off Kit

EXAIR manufactures a variety of nozzles that are OSHA safe, high quality, and very efficient.  In this blog, I would like to discuss the features and benefits of the EXAIR Flat Super Air Nozzles and how to build a system to fit your application.

The EXAIR Flat Super Air Nozzles are manufactured to blow a wide forceful stream of air.  Their patented design creates a high velocity, laminar air stream with minimal air consumption and low noise.  They come in two sizes; 1” (25mm) and 2” (51mm), and EXAIR stocks them in two different materials, zinc-aluminum alloy and 316 stainless steel.  With a metal construction, breakage is not a concern and performance is not sacrificed even in the harshest of environments.  I have seen many plastic flat nozzles that were broken in applications.  The noise level was loud, and compressed air was wasted.  The unique patented shims inside the EXAIR Flat Super Air Nozzles give three improvements to the design and function.   First, they come in different thicknesses to create a wide range of forces.  In conjunction with a regulator, you can “dial” in the correct amount of force from a breeze to a hurricane without overusing your air compressor.  The patented design also allows an even force across the entire width of the air nozzle.  Lastly, they help to entrain the free ambient air; so that less compressed air is required.  The high efficiency design will save you money.  The EXAIR Flat Super Air Nozzles are effective in uniform blowing; efficient; and superior in quality and durability.  You can watch a video blog on the importance of using our patented shim.

(Click on photo to go to blog)

To show the different types and styles of Flat Super Air Nozzles that EXAIR stocks, you can correspond to the model number make-up sheet below.

To give force adjustments to the individual Flat Super Air Nozzles, EXAIR offers a way to change the thickness of the shim to better suit your application.  You can increase or decrease the force of the nozzle by just removing two screws and changing the shim inside.  This is a unique feature as most competitive flat nozzles do not allow you to do this.  EXAIR offers different thicknesses of the patented shims in our Shim Sets.  The chart below corresponds the appropriate Shim Set to the Flat Super Air Nozzle.

Flat Super Air Nozzle to Shim Set Chart

What can make the Flat Super Air Nozzles even better?  More flexibility.  The Stay Set Hoses can add that flexibility to the Flat Super Air Nozzles.  They are designed to manually position the Flat Super Air Nozzle to accurately target the air stream.  They allow maneuverability to locate the nozzle at different heights or angles; and once positioned, the Stay Set Hose will hold the nozzle in place.  They come in different lengths from 6” (152mm) to 36” (914mm).  We carry two different styles of connections to adapt to any of the Flat Super Air Nozzles.  You can select the different lengths of Stay Set Hoses (SSH) to the Flat Super Air Nozzle by the model number make-up sheet below.

To build your system even further, EXAIR also can offer a Magnetic Base to your Stay Set Hoses and Flat Super Air Nozzles.  The Magnetic Base has a powerful magnet on the bottom to securely attach the blow-off nozzles vertically or horizontally.  This feature is great if you need to move the nozzles to different areas in your application.  EXAIR manufactures a one-outlet and a two-outlet design.  Each outlet has a ¼ turn valve to manually turn on or off the nozzle and only require one air supply inlet.  To add this product to the Flat Super Air Nozzle with the Stay Set Hose, you can use the model number make-up sheet below.

With the EXAIR Flat Super Air Nozzles, you can take advantage of the durability, safety, and efficiency for your blow-off device.  In addition, you can build a system that will best suit your requirements.  You can add different lengths of Stay Set Hoses and/or different Magnetic Bases.  With these combinations grouped into one model number and in stock for quick shipments, it makes it simple to purchase from EXAIR.  Just to let you know, they also come with a 30-day unconditional guarantee to try them out.  If you need any help in building your optimum blow-off system, you can speak to an Application Engineer at EXAIR.  They will be happy to assist you.

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

Gen4 Super Ion Air Knife Removes Fibrous Material from Conveyor Belt

Conveying System

A factory was having some issues in losing plastic material underneath and around their conveyor system.   The conveyor moved plastic fibers from an extrusion process into a hopper.   The conveyor belt was made of a rubber material that was 17” wide, and the plastic fiber was made from HDPE.  As the conveyor went around the end to dump the fibers into the hopper, some of it would stick to belt and sides of the conveying system.  Some fiber material would fall onto the ground which would require cleaning and loss of material.  They attempted to place a brush flap against the conveyor belt to knock the material off, but it was not very effective.  The brush flap actually generated more static as well as created wear marks on the belt from contact.  The customer sent a picture of the problem and wondered if EXAIR could help them with this application.

Gen4 Super Ion Air Knife Kit

With plastic fibrous material and rubber belts, the two non-conductive surfaces will generate static.  Static can have a strong force that will cause the material to “stick” to surfaces.  The higher the static voltage, the stronger the force.  As you can see in the photo, the material is sticking to the belt as well as to the sides.  For this application,  I recommended the model 112224 Gen4 Super Ion Air Knife Kit.  The Gen4 Super Ion Air Knife is uniquely designed to have two functions in this application.  The Super Ion Air Knife uses 40 parts of ambient air with every one part of compressed air, making it very efficient.  With the laminar air stream that comes from the Super Air Knife, it can carry both positive and negative ions from the attached Gen4 Ionizing Bar to remove any type of static charge.  With this combination, it becomes a very effective non-contact scraper to remove the fibers and not wear on the conveyor belt.  The model 112224 kit includes the 24” (610 mm) long Super Air Knife with a Gen4 Ionizing Bar attached; power supply, filter, regulator, and a shim set.

The reason for the 24” (610 mm) extended length was to keep the fibers from collecting to the outside area of the conveyor (as shown in the photo above).  With the compact and lightweight design, it could easily be positioned below the conveyor.  As the fiber material would come around the conveyor, the ions carried by the air stream would neutralize the static as well as remove the material from the belt and the sides.  When the customer mounted the Gen4 Super Ion Air Knife in place, the plastic fibers dropped into the hopper and not onto the floor underneath.

Spillage is wasteful, costly, and time consuming to cleanup.  If you have excess waste from your conveying system, EXAIR will have the product to help you.  For the customer above, the Gen4 Super Ion Air Knife made it possible to claim more material, removed the hazard from buildup on the floor, and reduced cleaning time.  You can contact an Application Engineer to review your application.

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

 

EXAIR Heavy Duty Dry Vac: Overview

Heavy Duty Dry Vac Family

When it comes to industrial vacuums, wouldn’t it be nice to have a durable, long lasting vacuum that is quiet?  There is such a vacuum that has these qualities; the EXAIR Heavy Duty Dry Vac System.  This vacuum system has no moving parts, no motors to fail, or bearings to wear.  They only require compressed air to operate.  The Heavy Duty Dry Vac is used to vacuum solid materials like plastic, sand, and even denser materials like steel shot.  The vacuum pumps are made from a hardened alloy construction to resist wear and abrasion, and it is designed to generate a strong vacuum level measuring -60” H2O (-15 KPa) at 80 PSIG (5.5 Bar).  To accommodate the multiple types of industrial applications, EXAIR offers the Heavy Duty Dry Vac Systems with different options and drum sizes.

The unique design of the Heavy Duty Dry Vac is incorporated in the modified lid that will fit onto a standard 55-gallon, 30-gallon, or 110-gallon drum (209L, 114L, or 418L respectively).  A 0.1-micron filter bag mounts in the center of the lid to allow excess air to escape and to contain the contamination inside the drum.  The large surface area of the filters allows for extended use before replacement while the high efficiency will keep the fine particles from re-entering the environment.  Under the drum lid, EXAIR used some features to help reduce the noise level even further.  We added a silencing foam and an extended hose.  This will muffle the noise and direct the contamination toward the bottom of the drum.  With these additional features, the noise level is only 82 dBA at 80 PSIG (5.5 bar).  Measure that against any electric vacuum.

Heavy Duty Dry Vac System

The Heavy Duty Dry Vac Systems come in three different options to best fit your application.  The standard option comes with the drum lid described above and a latching ring to attach to the drum.  It also comes with 10 feet (3m) of an anti-static hose, 20 feet (6m) of a compressed air hose, an aluminum chip wand, a hose hanger, a gauge, and a manual operational valve.  This option is available with three different drum sizes.  For example, model 6197 is for the 55-gallon drum (209L), model 6197-30 is for the 30-gallon drum (114L) and model 6197-110 is for the 110-gallon drum (418L).

Deluxe Heavy Duty Dry Vac System

The second option is the Deluxe Heavy Duty Dry Vac System.  This option will include all the items in the standard option plus aluminum tools, a tool holder and a drum dolly.  The upgraded aluminum tools include a floor tool, crevice tool, skimmer tool with detachable brush, and a two-piece double bend wand.  They are easily attached to the hose for quick cleaning of material spills.  The Deluxe system is a great option for getting into tight areas, hard-to-reach places, and large floor areas.  This option is also available in three drum sizes.  For example, model 6297 is for the 55-gallon drum (209L), model 6297-30 is for the 30-gallon drum (114L) and model 6297-110 is for the 110-gallon drum (418L).

Premium Heavy Duty Dry Vac System

If you do not have a drum to use in your facility, no problem.  EXAIR offers a steel drum in the Premium Heavy Duty Dry Vac Systems.  The Premium package has all the items in the Deluxe option plus a heavy-duty steel drum.  We offer the Premium option for all three sizes as well.  For example, model 6397 will include the 55-gallon drum (209L), model 6397-30 will included the 30-gallon drum (114L) and model 6397-110 will include the 110-gallon drum (418L).

If you get tired of throwing away your electric vacuums for burned up motors, you should try the EXAIR Heavy Duty Dry Vac System.  They will definitely extend the useful life, make it much quieter to operate and vacuum denser heavier materials quickly.  For U.S. and Canadian customers, we offer a 30-day unconditional guarantee to try the units.  If you need help to determine which Heavy Duty Dry Vac option would best suit your application, you can contact an Application Engineer at EXAIR.

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