Proper Supply Line Size And Fittings Provide Peak Performance

Many times when we provide the air consumption of an EXAIR product, we get a response like…. “I’ve got plenty of pressure, we run at around 100 PSIG”. While having the correct pressure available is important, it doesn’t make up for the volume requirement or SCFM (Standard Cubic Feet per Minute) needed to maintain that pressure. We commonly reference trying to supply water to a fire hose with a garden hose, it is the same principle, in regards to compressed air.

When looking to maintain an efficient compressed air system, it’s important that you use properly sized supply lines and fittings to  support the air demand (SCFM) of the point-of-use device. The smaller the ID and the longer the length of run, it becomes more difficult for the air to travel through the system. Undersized supply lines or piping can sometimes be the biggest culprit in a compressed air system as they can lead to severe pressure drops or the loss of pressure from the compressor to the end use product.

Take for example our 18″ Super Air Knife. A 18″ Super Air Knife will consume 52.2 SCFM at 80 PSIG. We recommend using 1/2″ Schedule 40 pipe up to 10′ or 3/4″ pipe up to 50′. The reason you need to increase the pipe size after 10′ of run is that 1/2″ pipe can flow close to 100 SCFM up to 10′ but for a 50′ length it can only flow 42 SCFM. On the other hand, 3/4″ pipe is able to flow 100 SCFM up to 50′ so this will allow you to carry the volume needed to the inlet of the knife, without losing pressure through the line.

Pipe size chart for the Super Air Knife

We also explain how performance can be negatively affected by improper plumbing in the following short video:

 

Another problem area is using restrictive fittings, like quick disconnects. While this may be useful with common everyday pneumatic tools, like an impact wrench or nail gun, they can severely limit the volumetric flow to a device requiring more air , like a longer length air knife.

1/4″ Quick Connect

For example, looking at the above 1/4″ quick disconnect, the ID of the fitting is much smaller than the NPT connection size. In this case, it is measuring close to .192″. If you were using a device like our Super Air Knife that features 1/4″ FNPT inlets, even though you are providing the correct thread size, the small inside diameter of the quick disconnect causes too much of a restriction for the volume (SCFM) required to properly support the knife, resulting in a pressure drop through the line, reducing the overall performance.

If you have any questions about compressed air applications or supply lines, please contact one of our application engineers for assistance.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

Not All Compressed Air Guns Are The Same

If you work in an industrial plant or manufacturing environment, chances are you use some type of compressed air gun for cleaning parts, work areas, etc. Many air guns purchased through large industrial suppliers are a common choice due to the cost of the gun but as the saying goes – “you get what you pay for”. These types of guns may be cheap to purchase but they are also made cheap and have parts that can break easily, like the trigger or nozzle. In many cases, the nozzles on these guns are also in violation of OSHA requirements, producing dangerous discharge pressures and loud noise levels, which can lead to costly fines or potentially deadly injuries.

EXAIR offers 5 different styles of Safety Air Guns that not only eliminate these concerns, but also provide a more efficient operation, which can reduce energy costs. All of our Safety Air Guns are fitted with our engineered Air Nozzles  which meet OSHA Standard 1910.242(b) for 30 PSI dead end pressure, as they provide a relief or safe path for the air to exit if the nozzle were to be blocked or pressed against an operator’s body so the exiting air pressure will never reach 30 PSIG. They are also engineered to entrain surrounding air across the profile of the nozzle, which produces a smoother airflow, ultimately reducing wind shear, resulting in much lower sound levels, meeting OSHA Standard 29 CFR 1910.95(a).

 

 

The Precision Safety Air Gun body is made of a durable high impact, glass reinforced nylon, providing for a lightweight, ergonomic operation. These guns feature a curved extension, ideal for delivering a powerful stream of air in hard to reach areas, like clearing debris from drilled holes. All of the nozzles used with these units are either 316ss construction for durable, corrosion resistance or PEEK plastic for non-marring applications. The air inlet is 1/4 FNPT and there is a convenient hanger available for safe storage.

 

 

 

Our NEW VariBlast Compact Safety Air Guns are ideal for light to medium duty processes, featuring a variable flow trigger to achieve different force levels ranging from 2.0 ounces up to 1 pound, depending on the nozzle. The body is cast aluminum and there are (2) 1/4 FNPT air inlets available, 1 on the bottom and 1 on the back of the gun, as well as a storage hanger, for easy installation. Nozzles are available in zinc aluminum alloy, 303ss, 316ss and PEEK plastic. These guns are available with aluminum extensions from 6″ up to 72″.

 

 

The Soft Grip Safety Air Guns are commonly used in long-term use applications as they feature a comfortable grip and long trigger which helps to reduce hand and finger fatigue. The cast aluminum construction is well suited for more rugged environments and again, features a hanger hook. These guns can be fitted with aluminum, stainless steel or PEEK plastic to meet the demands of a variety of applications and are available with 6″ – 72″ aluminum extensions for extra reach or Flexible Stay Set Hoses , allowing the user to aim the airflow to a specific target area. The air inlets for these guns are going to be 1/4 FNPT.

 

 

 

EXAIR’s Heavy Duty Safety Air Guns deliver higher force and flows than other air guns, as these units feature a 3/8 FNPT air inlet, which maximizes the compressed air flow to the engineered Super Air Nozzle. Like the Soft Grip, the durable cast aluminum body is designed for use in tough industrial processes, and the ergonomic and comfortable trigger are ideal for hours of use. Aluminum extension are available, again in lengths from 6″ up to 72″, but feature a larger diameter for optimal flow and superior durability.

 

The Precision, VariBlast, Soft Grip and Heavy Duty Safety Air Guns are ALL available with an optional, polycarbonate Chip Shield to protect personnel from flying chips and debris, further meeting OSHA Standard 1910.242(b) for the safe use of compressed air.

 

Lastly we offer our Super Blast Safety Air Guns. The Super Blast Safety Air Guns are ideal for wide area blowoff, cooling or drying a part, as well as long distances. They feature a comfortable foam grip and spring loaded valve that will shut off the airflow if the gun is dropped. These units use our larger Super Air Nozzles and Super Air Nozzle Clusters, providing forces levels from 3.2 lbs. up to 23 lbs. Depending on which nozzle is fitted on the assembly, air inlets will range from 3/8 FNPT up to 1-1/4 FNPT. Aluminum extensions are available in 36″ or 72″ lengths.

 

 

For help selecting the best product to fit your particular application, please contact one of our application engineers for assistance.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

 

Vortex Tube Cools Glue On A Paper Folding Machine

I recently worked on a cooling application with an engineering company who designed a paper folding machine for their customer. As the paper enters the machine, it travels over a series of rollers or “plows” that folds the paper into the desired design. At the last step a heated glue is applied to the edge so the paper stays folded. After the paper leaves the folder it is sent to a stack machine to be processed and packaged for shipment. It was at this area they were starting to see some issues arise as the glue was retaining heat, causing it to leak onto the dividers of the stacker or other finished papers.

Example of a paper folding machine

To try and remedy the situation, the customer had installed an air nozzle to blow compressed air across the last fold and while this did work somewhat, they had to operate at really low pressure so they didn’t cause the paper to move while trying to cool the glue. This slowed the process down, which was negatively affecting their production output, so they reached out for assistance on a more reliable solution.

After further discussing the process with the design company, I recommended they use our Model # 3908 Small Vortex Tube Cooling Kit. The Vortex Tube Cooling Kits include the Vortex Tube, cold muffler, tubing, filter separator and all of the generators to change the flow rate and cooling capacity of the Vortex Tube during operation. The temperature drop from the supply air temperature and the volume of air being exhausted can be controlled by adjusting the valve in the hot end to change the cold fraction (the percentage of air being exhausted out of the cold end versus the amount of air being exhausted out of the hot end).

Items included in a Vortex Tube Cooling Kit

By incorporating the Cooling Kit into the process, the customer would be able to experiment with the airflow and temperature to achieve an acceptable balance, providing enough cold air to cure the glue, while not disrupting the process. If you have a similar process you would like to discuss, please contact an application engineer at 800-903-9247 for assistance.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

The Folding Machine 4 image courtesy of Ms. Tharpe via creative commons license

EXAIR Leads the Way with Standards and Certifications

For over 34 years, EXAIR has been the industry leader in providing Intelligent Compressed Air Products to the industrial marketplace. While much of our focus is to ensure our products are engineered to provide optimal performance, we are also dedicated to manufacturing products that meet a wide range of standards and directives to promote safety in relation to plant personnel.

 

For instance, all of our compressed air operated products meet or exceed OSHA Standards 29 CFR 1910.242(b), requiring that the outlet pressure of an open pipe, nozzle, air gun, etc., when used for cleaning purposes, must remain below 30 PSI when dead-ended against the skin, as well as Standard 29 CFR 1910.95(a) as a way to protect workers from job related injuries related to dangerous sound levels of 90 dBA and higher.

 

 


Many of our products are also CE Compliant, meeting the mandatory requirements for products intended to be sold in the European Economic Area or “EEA”. For example our Electronic Flow Control and Electronic Temperature Control (ETC) meet the EU (European Union) Low Voltage Directive 2006/95/EC.

 

 

EXAIR electrically powered devices, like our Static Eliminators and Digital Flowmeters for example, comply with the “Restriction of Hazardous Substances” or RoHS Directive 2011/65/EU, including the amendment outlined in the European Commission decision L 214/65.

 

 

We are also committed to providing material that supports the conflict mineral free rule to help aid in the relief of illegal trade of exotic materials, like tungsten, gold, tin and tantalum in the DRC region. Using the CMRT 4.20 template, we document our supply resources to ensure we provide conflict free products, as outlined in Section 1502 of the Dodd-Frank Wall Street Reform and Consumer Protection Act.

 

Lastly, the European Union introduced the REACH program – Registration, Evaluation, Authorization and Restriction of Chemicals, as a method to register chemical substances being imported into the EU to protect people and the environment, per Regulation (EC) No 1907/2006 Title I, Article 3.  Also noted in the program, Title II, Article 7, they state that any product with a substance intended to be released under normal operating conditions, must be registered for quantities totaling more than 1 metric ton per year. Since EXAIR products do not intentionally release or contain any such substances, registration to meet the program is not required.

 

If you have any questions about any of these Standards or Directives or about which EXAIR products comply, please feel free to contact an application engineer for assistance. We’d be happy to help!

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

Super Air Wipe Controls Coating Thickness On Tubing

A large manufacturing company called looking for a better solution to control the thickness of a curing agent being applied to the outside of tubing used in the automotive industry. The tubing is formed in an extruder and travels through a liquid cooling chamber and then air dried. After the tubing is dried, it is sent to a spray chamber where the curing agent is applied to the exterior. On the exit side of the spray chamber, the customer had installed several flexible air lines placed around the perimeter of the tubing to blow air across the surface to help control the coating thickness. This worked somewhat but they were seeing an increase in the amount of rejected material as the air pattern was sporadic and uneven, which caused streaking and dry spots in certain areas of the tubing. They reviewed our web site and familiarized themselves with our Air Wipes but were unsure of the best design and size to fit their need so they reached out for assistance.

After further discussing the process, their tube O.D. sizes range from 3/8″ – 1/2″, making our 1″ Air Wipe the ideal solution. As far as the design, the Standard or Super Air Wipe, I recommended they use our Model # 2451 Super Air Wipe kit due to the aluminum construction and stainless steel wired braided hoses being able to withstand the potential temperature in the area of 200°F. The kit includes a filter separator to remove any water or contaminants in the supply and a pressure regulator which would allow them to control the flow and force of the exiting air, to help “dial” it in to fit the demand of the application.

Super Air Wipe is available in sizes from 1/2″ up to 11″ in Aluminum construction and up to 4″ in Stainless Steel construction.

 

EXAIR Air Wipes features a split design, which can easily be clamped around the material, to provide a 360° uniform airflow, perfect for treating the surface of round shapes, like extruded tubing. If you have an application where you are needing to dry, cool or clean the outside of a pipe, hose or cable, contact an application engineer for help making the best product selection.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

Engineered Air Nozzles Reduce Noise Levels and Outlet Pressure, Meeting OSHA Requirements

“My operators are complaining that our air guns are too loud, how can you help me?” – is a very common inquiry we receive here at EXAIR on almost a daily basis. Many open end blowoffs or air guns fitted with nozzles that have cross drilled relief holes create high pitch wind shear, resulting in excessive noise levels, sometimes exceeding 100+ dBA. This not only is a safety concern but also an OSHA violation.

Variety of Air Nozzles that produce dangerously loud noise levels

Loud noises and the length of exposure time can lead to significant health concerns such as long term hearing loss, increased stress levels and potential injury due to lack of concentration. The Occupation Safety and Health Administration (OSHA) introduced Standard 29 CFR 1910.95(a) as a way to protect workers from job related injuries associated to potentially dangerous sound levels. Per the Standard, at 90 dBA an operator is limited to a maximum of 8 hours of constant exposure. As noise levels increase, the allowable exposure time decreases, in some cases slowing production, costing a company on their bottom line.

 

EXAIR’s Air Nozzles are engineered so they entrain surrounding air across the profile of the nozzle, which produces a smoother airflow, ultimately reducing wind shear, resulting in much lower sound levels, meeting the OSHA Standard.

Illustration showing the air travel of our Super Air Nozzles

 

In addition, our Air Nozzles also meet the OSHA Standard 1910.242(b) for 30 PSI dead end pressure. All of our engineered Air Nozzles provide a relief or a safe path for the air to exit if the nozzle were to be blocked or pressed against an operator’s body so the exiting air pressure will never reach 30 PSIG.

All of EXAIR’s Air Nozzles are available with standard NPT threads to easily adapt to existing air guns. We also off our full line of Safety Air Guns which are fitted with our engineered nozzles, providing an “off-the-shelf” OSHA compliant solution. For help selecting the best product to replace your existing device or if you have a new application you would like to discuss, give us a call at 800-903-9247.

Justin Nicholl
Application Engineer
justinicholl@exair.com
@EXAIR_JN

 

Cleaning A Cookie Cutter Die Using A 24″ 316SS Super Air Knife

I recently worked with a food manufacturer who was looking for a way to clean the die roller in their cookie cutting process.The cutting machine is fed by a ribbon of extruded dough that is cut into various shapes as it passes by a 24″ wide roller. After the cookies are cut, the finished product then travels down a chute to a feed tray where it is conveyed to a packaging area. They were starting to see an increase in rejects as some cookies were being “double stamped” as a result of residual dough sticking to the die. They tried to install a brush traveling the span of the roller in an effort to wipe it clean but this wasn’t very effective and also caused some contamination as some of the bristles would break loose. They then tried having an operator use an air gun to manually clean the roller and while this did work, it severely slowed the process down, reducing production and negatively affecting their bottom line.

That’s a lot of cookie cutters!

After discussing the details of the application, I recommended the customer use our 24″ 316ss Super Air Knife in the application. The Super Air Knife produces a laminar sheet of air across the length of the knife and consumes only 2.9 SCFM per inch of knife length when operated at 80 PSIG. The 316ss construction resists pitting and is the preferred choice when being applied to a food process as it minimizes the potential for metal contamination.

SS Super Air Knife available in lengths from 3″ up to 108″

When it comes to wide area treatment, an Air Knife is the optimal choice. If you have a similar application that requires assistance, please contact an Application Engineer at 1-800-903-9247.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

 

Largest collection of cookie cutters I’ve ever seen image courtesy of Steven-L-Johnson via Creative Commons license.