Economic:

• Proptec sprayers operate at equal or faster ground speeds, resulting in more acres per hour.
• Proptec sprayers can reduce the amount of pesticide needed per job.
• It is common to see savings of 35% or more on pesticides when using a Proptec sprayer.
• Proptec sprayers reduce the amount of water to cover, sometimes by a factor of ten.
• By using less water, you can cover more acres per tank.
• On larger operations, one Proptec sprayer can often do the work of two or three conventional machines.
• Using less operators, less tractors, and less sprayers results in large savings.

Environmental:

• Proptec sprayers produce less drift and drip. Low drift means you get more out of the chemical you use.
• Low drift also means that Proptec sprayers have less potential for adverse impact on your neighbors.

Ergonomic:

• Electric controls in cab can reduce operator exposures when using Proptec sprayers.
• The available chemical eductor makes handling chemicals fast and easy.
• Available rinse tanks allow for in-field system purges, which reduce rinsate.

Rotary atomizers, which have been around since the 1950s, offer an applicator
several distinct advantages over nozzles worth looking at:

Air-Assisted Rotary Atomization

Rotary atomization is a process where drops of spray are expelled from the center of a rotating hub, then impact a high-speed rotating screen. This process pulverizes the drops, making a uniform droplet spectrum. As the droplets form, they mix with a highly turbulent airflow generated by the integral axial flow fan. When the airflow is aimed deep into the canopy, the spray-laden turbulent air penetrates the entire foliage, effectively covering all areas of the plant.

 

Air-Assist

Because the rotary atomizer does not need forced air to make the droplets, you have control of how much wind you create. Light foliage? Adjust the blades back. Heavy canopy? Crank them up- the atomizer just keeps on spraying. Proptec’s 10,000 CFM PER ATOMIZER is 40% more air per head than our next closest competitor. The difference means faster groundspeeds and better coverage, especially in heavy canopies.

 

The Power behind Proptec

Proptec rotary atomizers are built around ultra-high efficiency, case-drained hydraulic gear motors that supply ample power and dependability. There is no more efficient fan motor on the market today, electric or hydraulic- we use the worlds finest. At 5000-5500 rpm the atomizer produces a narrow spectrum of droplets averaging 60 to 120 microns. That is a faster fan speed than many of our  competitors use, but our superior components handle it easily, giving you more air and better canopy penetration.

The rotary atomizer's narrow droplet spectrum means you get the maximum number of droplets out of your spray, and more droplets means better coverage (keep reading!) fewer large droplets means less run off giving less soil and groundwater pollution. Proptec atomizers are designed to spray in a horizontal or downward direction, which also reduces drift.

 

Non-Wearing

Our rotary atomizer is much less susceptible to wear than a conventional spray tip. Even when they do wear, it does not significantly affect the droplet spectrum that is produced. A nozzle will change its pattern significantly as it wears.
Rotary atomizers are typically good for 3000 or more hours of operation, depending on how much wettable powder is applied (lots of WP applications can shorten the life to 1500 hours, but tht is rare). At that time, replace the basket (about 2 minutes of work), and they are good to go for another 3000 hours.

Non-Clogging

Watch the video to see the internal design of the Proptec atomizer. You will see that there are only large holes (5/32"), coarse stainless steel mesh,  and an open cup. It is nearly impossible to clog a Proptec atomizer. Even if "clogging" does occur, say, from not power-washing your sprayer for 2-3 years, the chemical will spill out the back of the cup and strike the blades, effectively atomizing the fluid and moving it out into the airstream.

Also, Proptec rotary atomizers are particularly good for spraying both thin, and very thick/chunky solutions. Want to spray nutritionals? Fish emulsion? Compost tea, sulfur, lime, copper, MOLASSES? These can cause serious trouble in conventional nozzles, but they are a piece of cake for Proptec.

Variable Rate

When coupled to a computer rate controller, it is possible to change your rate from less than 5 GPA to 100 GPA or more. With nozzles, you would have to change them several times to achieve that wide a range.  The Proptec Rotary atomizer always spins the same speed regardless of flow rate, so the droplet spectrum stays uniform. The rotary atomizers will continue to apply an effective spray pattern as the controller adjusts the rate. The Proptec Atomizer can apply as little as a few ounces/minute, all the way up to 4 Gallons per minute! Nozzles, on the other hand, have narrow ranges in which they operate, too low, they just dribble, too high, they'll never make it.

Operates Without Pressure

Since the atomizer itself requires no line pressure for operation, you can use low-pressure hose and fittings. Typically, The chemical system on a Proptec sprayer will run between 5 and 80 PSI, with pressure varying to achieve proper rate.

Good spray coverage can mean many things, depending on the chemical, pest, mode of action, time of year, and atmospheric conditions. That's a lot to consider, but there are a few trends. Generally, good front and backside coverage is most important in situations where contact with the pest is critical. This is most typically the case when spraying fungicides, insecticides, and miticides. Inadequate coverage when spraying these chemicals can leave pests behind to strike again. This means more sprays, more crop damage, and higher costs.

The Old Way

Conventional wisdom has said that drenching coverage, such as that done by 100-200 or more gallon-to-the-acre applications, gives the best chance at covering the entire plant. If you aren't getting good coverage, add more water. chances are, some of it will get where it needs to go. While there is some truth in that, conventional wisdom also says that 5% of the chemical does 95% of the work. While that may be a bit of an oversimplification, it is true that in many cases, control can be achieved with much less chemical than is typically used. The rest is lost to runoff, drift, or over-application. All that water and chemical costs you money, and doesn't do a thing for you. So how does a grower improve the situation?

Less Chemical Does More

Lets look at what happens when a plant is sprayed. Typically, the top of the outside leaves gets the best coverage. Usually, this is near 100% coverage, often to the point that excess chemical drips off the leaf. The deeper you go into the canopy, the less coverage is seen. Deep in the tree, or close to the ground in row crops, there may be almost no coverage, 5-10% or less.

"But I am getting control!" you say. If that is the case, then it is very likely that you do not need 100% coverage to get control with the chemicals you are using. After all, you killed the pests in the least-covered areas of the plant, with very little coverage, so much of the extra chemical that was deposited on the rest of the plant may have just killed your pests more dead!

"Yeah, I have problems with coverage. Our scouts are still finding pests in the field after we spray." If this is you, then you may not be getting adequate coverage. Fungus and bugs are hiding in the nooks and crannies of the plant, waiting for the danger to pass. Even worse, the low, sub-lethal doses they may be getting in their hiding spots could be breeding immunity! Take for example tart cherries. Lack of coverage is often obvious by the yellow crown of disease-stricken leaves in the tops of the trees. In mature cotton, scouts will often recommend not spraying if the infestation is in the bottom 1/3 of the canopy. They know that otherwise effective chemicals will not work if they can't get to the pest!

Increase coverage in the least-covered parts of the plant.
Decrease coverage in the most-covered parts of the plant.

It used to be that to increase coverage, you increased water. But what does the water do for you? Really, only two things: carry the chemical, and dilute it. In most cases, the water is gone in seconds or minutes by evaporation, leaving the crop with a thin sheet of chemical left on it. In places where coverage was not 100%, small islands of dilute chemical residue dot the plant to varying degrees. So when you ar not getting drenching coverage, is what your getting good coverage?

In a perfect world, an applicator would increase the coverage in the lowest covered areas of the plant or tree to increase efficacy. In many cases, it may only be necessary to increase to 5% or 10% total coverage, especially if the droplets are uniformly distributed (we'll get into that later). In that same perfect world, that operator would reduce the coverage in the best covered areas to a level closer to that minimum effective coverage area. This is basically the goal of low-volume spraying. The problem is, What is minimum effective coverage?

Novartis Corporation offers the following guidelines for low volume spraying:

Less water does not mean less coverage! Let's talk about droplets. Typically, with conventional sprayers, an applicator sprays with high gallonage, and relatively large droplets. The bigger the droplet size, the more the drop weighs. These large, heavy drops travel in straight lines from the nozzle, and strike the first surface in their path, typically the outside topside of the leaf canopy. This is often the part of the plant that is least vulnerable to disease. Increasing spray pressure will add energy to move the top leaves aside, and allow better penetration, but you still need to carry and deliver all that water. Increasing the pressure also increases the number of very small drops.

Small drops can be a blessing or a curse, depending how they are used. They are great for two reasons: first, the more small drops you have, the more surface area you get out of a gallon of water. This means a potential for more coverage with the same gallon of spray, or the same coverage out of much less spray.

Look at the effect small droplets has on your ability to cover the plant:

1 micron is 1/25,400 or 4 x 10^-5 inches. Heavy fog is 5-10 micron droplets. Light rain is 1000 or more microns. Your hair is about 100 microns thick.

By using smaller droplets, your number of hits can increase dramatically, without having to spray more gallons. The second good thing about smaller droplets is that the smaller a drop gets, the less it is influenced by gravity, and the less momentum it has. Why does that matter? because a small droplet is more likely to travel around the outside leaves and weave its way more deeply into the canopy, allowing it to deposit in difficult to reach areas.

On this grape sprayer, you see output that would approximate 20 gpa at 3.5 MPH. The plume looks like those made by sprayers using much higher volumes, because of the small, more uniform droplet spectrum. You can see that virtually no spray is traveling out of the target zone, minimizing opportunities for the wind to catch it.

Small droplets can be more difficult to control in conventional sprayers. Why? because as they are formed at the nozzle, they lose there speed very rapidly. Once they have slowed down, they are susceptible to even very slight breezes. Left to their own devices, they are prone to drift away on the wind, never reaching the intended target. That leads to the next piece of the puzzle.

Small Drops + Forced Air = good coverage.

Adding forced air is a huge improvement in penetrating the canopy. It does two things: It opens and turns the canopy, exposing more surfaces to spray. Secondly, it forces the spray more deeply into the canopy, displacing the clean air with spray-laden air. Ideally, all the air is replaced. Once those small droplets are buried in the canopy, they are much less prone to drift. Experience shows that once inside the canopy, they will wrap around round objects (like fruit) covering surfaces that were not in a direct line of sight to the spray source, and giving overall improved coverage.

So where does Proptec fit into this?

For those of you who are extremely interested in droplet size, Proptec creates a 60 micron NMD (numeric mean diameter) and 100 VMD (volume mean diameter) average droplet spectrum (feel free to request spectrum curves). NMD is the average droplet size at which half of the droplets are smaller, and half are larger. VMD is the droplet size at which half of the spray volume is contained in larger droplets, and half is contained in smaller droplets. Both tell you different things. NMD will give you a better idea of how many hits you will have in a gallon of spray, the information that we feel is more valuable in low volume spraying. A low NMD means that you have lots of very small droplets and very few large ones. VMD may tell you very little about the actual droplet sizes you are spraying, but does tell you where most of your active ingredients are and is the most commonly used value. Typically, the closer an atomizer's NMD and VMD, the more uniform the droplet spectrum.

Proptec's spectrum is an ideal compromise of droplet size and weight: small enough to flow with the air into the canopy, and large enough to minimize losses to evaporation and drift. This atomization is coupled with a highly turbulent, high volume airflow. Airspeed velocities of up to 70 miles per hour and volumes exceeding 10,000 cubic feet per minute, per atomizer, provide thorough, uniform coverage without the possibilities of damaging foliage or fruit. This awesome air stream also gives the applicator unprecedented ability to apply chemicals in winds that would shut sown most other spray rigs. The spray-laden carrier air pushes past the outer canopy and swirls through the interior of the plant, dramatically increasing coverage in the least covered areas, while minimizing over-application on the outer surfaces.

Don't get too hung up on droplet size, though. Surfactants, tank concentrations, ambient temperature and humidity, and distance to target, are only a few factors that can affect the droplet spectrum. Some can affect it very significantly. The important thing is to get small drops, aim them properly, and drive them deep into the target canopy with enough air. Proptec will do that for you.

Orientation:

• In vertical crops such as bushes, vines, and orchards; drift is reduced by aiming the spray horizontally or downward.
• The spray stays in the canopy, avoiding the above-canopy winds that cause drift.
• For an example of how we can reduce drift, please click here for a short video.

Release Point :

• Since the small droplets from Proptec sprayers are entrained (captured) in the carrier air, they are carried with it deep into the canopy, where they are sheltered from ambient winds until they have time to deposit.
• In horizontal boom applications, with a conventional spray tip of a similar droplet spectrum, the smalldroplets have very little of their own momentum; meaning they slow down shortly after leaving the nozzle.
• If a conventional nozzle is too far away from the foliage, the droplet may get carried away in the wind before settling onto the plant.

Reduced Total Exposure :

• By using lower rates of active ingredient, Proptec sprayers use less chemical per acre; and are therefore less available for drift.
• Also, low-volume spraying means that little to no chemical drips on the ground, because you aren't spraying your crop to the point of saturation.
• Keeping chemical on the leaves reduces off-target losses that can potentially contaminate groundwater and increase costs.