In rugged industrial environments the EXAIR Heavy Duty Safety Air Gun delivers powerful blasts of compressed air right where it is needed. It features a 3/8 NPT metal inlet to allow for increased air flow to the Super Air Nozzle of your choice and there are many configurations are available from stock. It is constructed of a durable and robust cast aluminum body with an ergonomic and comfortable composite grip that allows for extended use without fatigue.
The Heavy Duty Safety Air Gun can be configured with extensions that are available in 6” increments up to 24” in length and 12” increments from 24” up to 72”. Combine the extension with our optional Chip Shield for maximum operator safety and comfort.
We offer a wide variety of nozzles to allow you to configure the Heavy Duty Safety Air Gun to you specific application. EXAIR has a large selection of nozzles that are engineered to entrain surrounding air with the compressed air supply creating a synergistic blast that is very powerful. Most importantly they operate much quieter than the limits of OSHA standard 29 CFR 1910.95(a) and can’t be “dead ended” therefore meeting OSHA standard 29 CFR 1910.242(b).
The EXAIR Heavy Duty Safety Air Gun is available in the configurations shown below or many others. If you have an application you would like to discuss or to see how the Heavy Duty Safety Air Guns will improve your process, give us a call, we are happy to help.
Compressed air regulators are a pressure reducing valve that are used to maintain a proper downstream pressure for pneumatic systems. There are a variety of styles but the concept is very similar; “maintain a downstream pressure regardless of the variations in flow”. Regulators are very important in protecting downstream pneumatic systems as well as a useful tool in saving compressed air in blow-off applications.
The basic design of a regulator includes a diaphragm, a stem, a poppet valve, an orifice, compression springs and an adjusting screw. I will break down the function of each item as follows:
Diaphragm – it separates the internal air pressure from the ambient pressure. They are typically made of a rubber material so that it can stretch and deflect. They come in two different styles, relieving and non-relieving. Relieving style has a small hole in the diaphragm to allow the downstream pressure to escape to atmosphere when you need to decrease the output pressure. The non-relieving style does not allow this, and they are mainly used for gases that are expensive or dangerous.
Stem – It connects the poppet valve to the diaphragm. This is the “linkage” to move the poppet valve to allow compressed air to pass. As the diaphragm flexes up and down, the stem will close and open the poppet valve.
Poppet valve – it is used to block the orifice inside the regulator. It has a sealing surface to stop the flowing of compressed air during zero-flow conditions. The poppet valve is assisted by a spring to help “squeeze” the seal against the orifice face.
Orifice – it is an opening that determines the maximum amount of air flow that can be supplied by the regulator. The bigger the orifice, the more air that can pass and be supplied to downstream equipment.
Compression springs – they create the forces to balance between zero pressure to maximum downstream pressure. One spring is below the poppet valve to keep it closed and sealed. The other spring sits on top of the diaphragm and is called the adjusting spring. This spring is much larger than the poppet valve spring, and it is the main component to determine the downstream pressure ranges. The higher the spring force, the higher the downstream pressure.
Adjusting screw – it is the mechanism that “squeezes” the adjusting spring. To increase downstream pressure, the adjusting screw decreases the overall length of the adjusting spring. The compression force increases, allowing for the poppet valve to stay open for a higher pressure. It works in the opposite direction to decrease the downstream pressure.
With the above items working together, the regulator is designed to keep the downstream pressure at a constant rate. This constant rate is maintained during zero flow to max flow demands. But, it does have some inefficiencies. One of those issues is called “droop”. Droop is the amount of loss in downstream pressure when air starts flowing through a regulator. At steady state (the downstream system is not requiring any air flow), the regulator will produce the adjusted pressure (If you have a gage on the regulator, it will show you the downstream pressure). Once the regulator starts flowing, the downstream pressure will fall. The amount that it falls is dependent on the size of the orifice inside the regulator and the stem diameter. Charts are created to show the amount of droop at different set pressures and flow ranges (reference chart below). This is very important in sizing the correct regulator. If the regulator is too small, it will affect the performance of the pneumatic system.
The basic ideology on how a regulator works can be explained by the forces created by the springs and the downstream air pressures. The downstream air pressure is acting against the surface area of the diaphragm creating a force. (Force is pressure times area). The adjusting spring force is working against the diaphragm and the spring force under the poppet valve. A simple balanced force equation can be written as:
Fa ≡ Fp + (P2 * SA)
Fa – Adjusting Spring Force
Fp – Poppet Valve Spring Force
P2 – Downstream pressure
SA – Surface Area of diaphragm
If we look at the forces as a vector, the left side of the Equation 1 will indicate a positive force vector. This indicates that the poppet valve is open and compressed air is allowed to pass through the regulator. The right side of Equation 1 will show a negative vector. With a negative force vector, the poppet valve is closed, and the compressed air is unable to pass through the regulator (zero flow).
Let’s start at an initial condition where the force of the adjusting spring is at zero (the adjusting screw is not compressing the spring), the downstream pressure will be zero. Then the equation above will show a value of only Fp. This is a negative force vector and the poppet valve is closed. To increase the downstream pressure, the adjusting screw is turned to compress the adjusting spring. The additional spring force pushes down on the diaphragm. The diaphragm will deflect to push the stem and open the poppet valve. This will allow the compressed air to flow through the regulator. The equation will show a positive force vector: Fa > Fp + (P2 * SA). As the pressure downstream builds, the force under the diaphragm will build, counteracting the force of the adjusting spring. The diaphragm will start to close the poppet valve. When a pneumatic system calls for compressed air, the downstream pressure will begin to drop. The adjusting spring force will become dominant, and it will push the diaphragm again into a positive force vector. The poppet valve will open, allowing the air to flow to the pneumatic device. If we want to decrease the downstream air pressure, the adjusting screw is turned to reduce the adjusting spring force. This now becomes a negative force vector; Fa < Fp + (P2 * SA). The diaphragm will deflect in the opposite direction. This is important for relieving style diaphragms. This deflection will open a small hole in the diaphragm to allow the downstream air pressure to escape until it reaches an equal force vector, Fa = Fp + (P2 * SA). As the pneumatic system operates, the components of the regulator work together to open and close the poppet valve to supply pressurized air downstream.
Compressed air is expensive to make; and for a system that is unregulated, the inefficiencies are much greater, wasting money in your company. For blow-off applications, you can over-use the amount of compressed air required to “do the job”. EXAIR offers a line of regulators to control the amount of compressed air to our products. EXAIR is a leader in manufacturing very efficient products for compressed air use, but in conjunction with a regulator, you will be able to save even more money. Also, to make it easy for you to purchase, EXAIR offer kits with our products which will include a regulator. The regulators are already properly sized to provide the correct amount of compressed air with very little droop. If you need help in finding the correct kit for your blow-off application, an Application Engineer at EXAIR will be able to help you.
The Vortex Tube makes cold air for the same reason that a can of compressed air gets cold when I clean my computer keyboard, right?
That’s a common question, and since they both start with compress air and end up with cold(er) air, it’s not an unreasonable assumption. But the answer is no; they’re not the same. Both are curious physical phenomena, though:
Cans of compressed air get cold while they’re discharging because of a thermodynamic principle known as the adiabatic effect. When you pressurize a gas by compressing it into a container, you’re putting all those molecules into a smaller volume of space…and you’re adding potential energy by the compression. Then, when you release that gas back to atmospheric pressure, that energy has to go somewhere…so it’s given off in the form of heat – from the air inside the can, as the pressure inside the can decreases. Now, the air that’s not under as much pressure as it was when you pushed the button on top of the can is going to start coming out of the can pretty soon. I mean, there’s only so much air in there, right? So, since it’s given off that energy immediately upon the drop in pressure, when it comes out of the can, it’s at a lower temperature than it was before you started spraying it out.
Vortex Tubes, on the other hand, generate a flow of cold air by a completely different phenomenon of physics called, maybe not so curiously, the Vortex Tube principle:
Air Wipes, which provide 360 degree blowoff, are typically used to remove heat, liquid, debris or static from wire, cable, pipe, tube, or extrusions.
We had a customer that was using a block type Air Wipe from a competitor to remove water from an extrusion. These air wipes are built using a plastic material, typically with some additional ceramic insert to resist abrasion of the wire, the halves are hinged with air holes drilled into each half which carries air through the block and on to the wire. They were using these block air wipes on several lines. The interesting point of this blog is that it required 5 block type air wipes to equal the results of 1 EXAIRSuper Air Wipe.
Since EXAIR’sSuper Air Wipe equaled the performance of 5 of the competitors it consumed less air was less expensive and produced less noise. Also in space sensitive applications the EXAIR Super Air Wipe is much thinner than the block type. To highlight this the Super Air Wipe is 1.13″ thick on all 11 models that range from 3/8″ to 11″ throat diameter. The performance of the block air wipe can only be changed by altering the inlet air pressure while the EXAIRSuper Air Wipe can also be changed by adusting the inlet air pressure OR by adding an additional shim the force can be nearly doubled!
Many of these block type air wipes use a series of holes to direct the compressed air supply at an angle over the material that needs to be cleaned off. EXAIR’sSuper Air Wipe being an engineered compressed air product use’s fluid dynamic’s to create more force as demonstrated below. The air from EXAIR’s Super Air Wipes is a continuous 360 degrees, without the gaps a series of holes creates.
Compressed air flows through the inlet (1) of the Air Wipe into the annular chamber (2). It is then throttled through a small ring nozzle (3) at high velocity. This primary airstream adheres to the Coanda profile (4), which directs down the angled surface of the Air Wipe. A low pressure is created at the center (5) inducing a high volume flow of surrounding air into the primary airstream. As the airflow leaves the wipe, it creates a conical 360° ring of air that attaches itself to the surface of the material running through it (6) uniformly wiping the entire surface with the high velocity airflow.
Block type air wipes are generally available in standard sizes up to 7″ in diameter while EXAIR’sSuper Air Wipes are available in stock diameters up to 11″ and we also offer custom sizes to suit many other applications.
If you have any items that need to have a 360 degree blowing pattern, I would enjoy hearing from you…give me a call.
From now through May 31, 2018, we are offering a FREE Vac-u-Gun with any order for one of our Industrial Housekeeping Vacuum Systems. The Vac-u-Gun is a multi-purpose tool that can be used to vacuum or transfer material from one location to another or it can be used as a powerful blow gun to clean debris off of the surface of a part or workstation. There is no electricity required to operate and no moving parts to wear out, providing for a safe, maintenance free operation.
When choosing one of our vacuums, selection can be simplified depending on what type of media you are needing to pickup. Our systems are going to be either solids handling or liquid handling.
Our Chip Vac Systems are the ideal choice when looking to vacuum dry or damp debris left over from machining operations and delivers them to a standard open top steel drum. For more abrasive material, such as sand or steel shot used in sandblasting processes, the Heavy Duty Dry Vac provides superior wear resistance due to it’s proprietary hardened alloy construction.
Our Chip Trapper and High Lift Chip Trapper are also used in liquid applications but these systems incorporate a filter bag inside the drum to capture any suspended solids in the liquid so only clean fluid is pumped back into the reservoir or tank.
In dusty applications we offer the Heavy Duty HEPA Vac which uses the same vacuum as the HD Dry Vac but this system provides a higher level of filtration meeting HEPA requirements of 99.97% filtration at the 0.3 micron level.
All of these products are In-Stock, Ready To Ship.
To take advantage of the offer, you need to order using the promotional Model number. Ordering is easy – you can email the order to firstname.lastname@example.org or place your order online at www.EXAIR.com. If you’d rather place your order over the phone or have any technical questions about our products, you can call us at 800-903-9247 and one of our reps will be happy to assist.
Energy…all day (and night) long, we humans are surrounded by – and bombarded by – all kinds of energy. Sometimes, the effects are pleasant; even beneficial: the warmth of the sun’s rays (solar energy) on a nice spring day is the sure-fire cure for Seasonal Affective Disorder, and is also the catalyst your body needs to produce vitamin D. Good things, both. And great reasons to get outside a little more often.
Sometimes, the effects aren’t so pleasant, and they can even be harmful. Lengthy, unprotected exposure to that same wonderful sun’s rays will give you a nasty sunburn. Which can lead to skin cancer. Not good things, either. And great reasons to regularly apply sunblock, and/or limit exposure if you can.
Sound is another constant source of energy that we’re exposed to, and one we can’t simply escape by going inside. Especially if “inside” is a factory, machine shop, or a concert arena. This brings me to the first point of today’s blog: sound power.
Strictly speaking, power is energy per unit time, and can be applied to energy generation (like how much HP an engine generates as it runs) or energy consumption (like how much HP a motor uses as it turns its shaft) For discussions of sound, though, sound power level is applied to the generation end. This is what we mean when we talk about how much sound is made by a punch press, a machine tool, or a rock band’s sound system.
Sound pressure, in contrast, is a measure of the sound power’s intensity at the target’s (e.g., your ear’s) distance from the source. The farther away you get from the sound’s generation, the lower the sound pressure will be. But the sound power didn’t change.
Just like the power made by an engine and used by a motor are both defined in the same units – usually horsepower or watts – sound power level (e.g. generation) and sound pressure (e.g. “use” by your ears) use the same unit of measure: the decibel. The big difference, though, is that while power levels of machinery in motion are linear in scale, sound power level and pressure scales are logarithmic. And that’s where the math can get kind of challenging. But if you’re up for it, let’s look at how you calculate sound power level:
Wo is reference power (in Watts,) normally considered to be 10-12 W, which is the lowest sound perceptible to the human ear under ideal conditions, and
W is the published sound power of the device (in Watts.)
That’s going to give you the sound power level, in decibels, being generated by the sound source. To calculate the sound pressure level:
Lw is the sound power level…see above, and
A is the surface area at a given distance. If the sound is emitted equally in all directions, we can use the formula for hemispheric area, 2πr2 where r=distance from source to calculate the area.
These formulas ignore any effects from the acoustic qualities of the space in which the sound is occurring. Many factors will affect this, such as how much sound energy the walls and ceiling will absorb or reflect. This is determined by the material(s) of construction, the height of the ceiling, etc.
These formulas may help you get a “big picture” idea of the sound levels you might expect in applications where the input data is available. Aside from that, they certainly put into perspective the importance of hearing protection when an analysis reveals higher levels. OSHA puts the following limits on personnel exposure to certain noise levels:
EXAIR’s line of Intelligent Compressed Air Products are engineered, designed, and manufactured with efficiency, safety, and noise reduction in mind. If you’d like to talk about how we can help protect you and your folks’ hearing, call us.
I recently had a chat conversation with a customer who was looking to cool the tooling on his CNC router, mill and lathe in his small machine shop. During the machining process, as the tooling would begin to heat up, it would warp the bit, causing irregularities in the finished product. In some cases the tooling was getting so hot, it would actually break, creating a safety concern.
He had reviewed some of our cooling products and was thinking of using our Cold Gun in the application but was concerned with the air demand. The Cold Gun consumes 15 SCFM @ 100 PSIG and provides a 50°F temperature drop (from supply temperature) with 1,000 Btu/hr. of cooling capacity. The problem was that his compressor only produces a little over 9 SCFM. I explained that the existing compressor would in fact be undersized as it doesn’t produce enough volume to keep up with the demand of the Cold Gun.
Due to the limited amount of compressed air available, our Mini Cooler System, Model # 3808, would be the better solution. The Mini Cooler also provides a 50°F temperature drop with a little less cooling power, 550 Btu/hr., but this system only requires 8 SCFM @ 100 PSIG, falling within the existing compressor’s output capacity. The Mini Cooler also includes a magnetic base as well as flexible tubing to direct the cold air to the desired location, making it easy to move from machine to machine.
If you are considering an EXAIR product for an application or have additional questions about performance, contact an application engineer for assistance in making the best selection.