Category: Speciality Sprayers

Main category for all sprayers that are not horizontal booms

Boomless Nozzle Performance
NOTE: This article has proved very popular, and subsequently we received emails with additional information. The article has now been expanded to include work performed by Dr. Bob Wolf et al.
Part 1:
Boomless nozzles are used for vegetative management activities where it’s not practical, or sometimes even impossible, to use a horizontal boom. Consider highway easements and ditches, railways, and infrastructure like buildings, powerline poles or fence posts. In these cases, the booms would hit uneven ground, trees and other obstacles. Enter the boomless nozzle.
Unlike a typical flat fan nozzle, these nozzles direct spray laterally in one or two directions, creating a very wide spray pattern. Some field sprayers use a smaller version such as an off-centre or uneven fan to either extend the booms’ coverage (e.g. to get around fence posts) or give the pattern a discrete edge and not spray beyond the booms length.
There are many varieties of boomless nozzle available, but they don’t give the same performance.
Using a spray pattern table, Helmut Spieser and I compared coverage patterns from three popular tips:
- The Boom X Tender
- The Boom Buster
- XP BoomJet
The Boom X Tender
With seven rates to choose from, this nozzle claims up to 13′ throw from tip to the edge of the swath. When we ran the tip at 40 psi we noticed a lot of inconsistency in the pattern, where it clearly had variation in flow along the swath. Note the red arrows in the image.
These inconsistencies made themselves known when we observed the pattern produced on the spray table. We achieved a 7.5′ swath at 40 psi, 16″ above the table with the XT024 (yellow) tip. The coverage wasn’t very even.
The Boom Buster
There are fourteen nozzles to choose from, each delivering different flows and according to the manufacturer, spanning up to 31′ from the tip to the edge of the swath. An interesting feature when we ran this nozzle was that the fan extended back ~15°, which might eliminate the need for a centre nozzle if two were operated at the same time with sufficient overlap.
We achieved a 7′ swath at 40 psi, 16″ above the table and the coverage described a fairly consistent curve. It did taper at the far end, but did a respectable job. It was obvious some overlap at the 15° end would help level out the response, and when paired with a second tip facing the opposite direction, this would work well.
The XP BoomJet
The BoomJet mounts 90º to the swath, and with five rates to choose from claims a swath up to 18.5′ from tip to edge.
We mounted the (B) 1/4XP20L (You have to specify left or right) 16″ above the table and at 40 psi we achieved a 6′ swath. There was an odd dip in the coverage pattern not far from the tip. We suspected it might be an artifact, but after multiple attempts it persisted. Other than that dip, the pattern was quite consistent. Had we adjusted the angle to reach a 7′ swath, it may have tapered as much as the Boom Buster.
Observations
Given the range of possible rates and swath distances, the overall consistency of the swath, the conventional nozzle mount, and the 15º overlap, Helmut and I chose the Boom Buster. The BoomJet was a close second, with a consistent pattern save the odd dip, but the 90º mount while making it possible to elongate or shorten the swath was a bit finicky and could pose a snagging risk. The Boom X Tender ranked third because of the inconsistent coverage.
Part 2:
Nozzle mounted on the front bumper of a County Highway Spray Truck used to spray ditches in Kansas.
Boomless nozzles are often used on all-terrain vehicles (ATV’s) equipped with small-capacity spray tanks and they’re popular for for eliminating weeds in pastures and rangelands as well as along roadsides. In 2009, Kansas State University published a factsheet evaluating the efficacy of boomless spray nozzles and describing how they can best be used. What follows is a summary of the findings from their field trials.
Considerations for using boomless nozzles
1. Pick a nozzle that best fits the mode of action of the herbicide being used.
2. Select spray width to achieve uniform distribution.
3. Both the height of the vegetation, and the prevailing wind, will interfere with the width of the spray swath.
4. As with any hydraulic nozzle, pressure should be optimized to achieve the desired droplet size and swath width while reducing drift potential.
Field Trials
Applications were tested on small (growth stage prior to jointing and 4-5 inches tall) and large (growth stage after jointing and 24-30 inches tall) wheat crops planted in 20 foot wide strips. The nozzles tested were the BoomJet (XP) , Boom X Tender (XT) , Boom Buster (BB) and the Combo-Jet (WCJ). Glyphosate and paraquat were applied a typical ATV-mounted set-up. The treatments were replicated three times and water sensitive paper was used to analyze droplet size.
The Combo-Jet nozzle group.
Results
The mode of action, coverage and droplet size affected the results in both short and tall wheat. As expected, glyphosate served as the 100% control and paraquat efficacy ranged depending on the nozzle (see Graph 1). The XT gave the best performance with paraquat.
Graph 1 – Percent Control in Large Wheat
Spray (control) uniformity was about equal with glyphosate, but with paraquat, on a scale of 1-10 with 10 being the highest level of control, the XT and BB tied for best (Graph 2).
Graph 2 – Spray Uniformity in Large Wheat
Swath width was considerably less than manufacturers claimed in the tall wheat (Graph 3). Based on width of control, the WCJ had the widest swath.
Graph 3 – Swath Width in Large Wheat
Swath width was somewhat less than manufacturers claimed in the short wheat (Graph 4). Based on width of control, the XT had the widest swath.
Graph 4 – Swath Width in Small Wheat
Median droplet size ranged from 684 to 799 microns (Graph 5). If we assume the preferred range for coverage/weed control is 300-500 microns, all nozzles were on the high end. It should be noted that this does reduce drift potential.
Graph 5 – Droplet Size as VMD (microns)
Percent coverage ranged from 37.5 to 27.0 for paraquat and 28 to 21.3 for glyphostate (Graph 6).
Graph 6 – Percent Coverage
Observations
The wind direction and height of the spray stream likely affected the results. To achieve the manufacturer-rated swath width, nozzles would have to be mounted higher on the ATV than is practical, and this would lead to increased drift potential. It was noted that the large orifices common to boomless nozzles made it difficult to pressurize with pumps typically used on ATV’s and a more powerful pump (e.g. a roller pump) might provide better swath width.
While there are many parameters to consider, and counter to the lab trials performed in Part 1, the results from Part 2 suggest the Boom X Tender and Boom Buster gave better overall performance.
Checking the Boom Buster spray pattern.
Overall Conclusions from Part 1 and Part 2
It can be frustrating testing nozzles. What works wonderfully one day might not be worth the materials they’re made of the next. Obviously there was no clear “winner” at the end of this article, but that’s just as well, because perhaps that’s the wrong take home message.
Instead, remember that any nozzle can be used incorrectly. Mind the pressure, swath width and environmental conditions to get the most out of whichever nozzle you choose to use. Take time to confirm that everything is working optimally, and go back to ground-proof the results so you know what worked and what didn’t.
April 20, 2016
Strategies to Spray the Top of a Perennial Canopy
Orchardists, nurserymen and hop growers share something in common – they want to get spray to the top of a tall plant canopy with as little waste as possible. The tops of trees, for example, are a primary site of infection as they filter spores from the air, so fungicide coverage is critical. Spraying the tops of high canopies (e.g. too high for over-the-row style sprayers) can be a difficult proposition.
Here are a few considerations:
- Wind moving through a planting, as a general rule, is twice as fast at the top of a canopy as it is at the ground. Wind carries spray off target.
- The further the distance a droplet travels, the smaller it gets as it evaporates and the less momentum it has. The likelihood of it hitting the target is greatly reduced.
- The top of a canopy typically has far less plant material than the rest of the canopy. Relatively speaking, there’s not much there to hit.
In order to overcome these challenges, the traditional axial orchard sprayer is nozzled with a larger proportion of spray distributed at the top of the boom. The idea is to increase the odds of some spray making it to the top of the canopy. Often, full-cone nozzles are used to accomplish this. Of course, if an estimated 10% of the spray actually impinges on the top of the canopy, the rest goes… well, somewhere else. This shotgun approach is hardly an efficient use of chemical.
Another strategy is to crank the PTO rpm’s up to 540, throw the fan in high gear and blow the spray as high as possible. The problem is, by increasing air speed and volume to carry spray to the top, the rest of the canopy (far closer to the sprayer) gets overblown and spray shoots right through. Some overspray might hit the next row, but most ends up on the alley floor. If you doubt it, consider how white your pant-legs get when you walk an orchard after spraying kaolin clay.
Others, mistakenly, might elect to raise the operating pressure to >150 psi in the hope that pressure will drive the droplets in a straight line at higher speeds. Most airblast sprayers using hollow cone patterns create very fine spray quality, even at 100 psi. Raising pressure means the droplets get even smaller, and tiny droplets have very little momentum. Increasing pressure just makes the problem worse.
Here’s what we propose.
Deflectors
If using an axial sprayer, employ air deflectors at the top of the air outlet to channel air (and spray) more effectively. The commercially-available deflectors are often just flat sheets, and air hits the surface and spills over all edges. Image pouring water onto a dinner plate – it just splashes over any which way. Better to replace those deflectors with a set that feature side-walls to channel the air. Anyone with access to a break and some sheet metal can make their own, but ensure they do not stick out beyond the wheel of the sprayer or they could snag plants and trellises. Always aim to overshoot the canopy top by a small factor to compensate for unexpected gusts of wind – better to overshoot a bit than to miss.
Commercial deflectors may or may not have channeling side walls. Inset: Homemade deflectors can do a great job.
The original Munckhof deflectors were reversed, and a larger set of extensions were fabricated and attached.
Towers
Better than deflectors, some sprayers move the air and nozzles closer to the target via ducted tower assemblies. They work very well, but they must be as tall as the target you intend to spray. Even then, an uneven alley can cause them to rock and you might still miss some upper targets. Operators using adjustable towers or ducts might angle them back to aim the air (and spray) on a slight upward angle rather than parallel to the ground, and that can compensate for a slight height difference, but it begins to defeat the purpose.
Nozzle body on upper tower deflectors. Still some air assist and a good idea, but use air induction nozzles.
Extra Nozzle Bodies
Some creative operators have attached additional nozzle bodies to the tower’s top deflector plate to aim it up in the top of the canopy. Still others have extended the wet boom itself higher than the tower. Unfortunately, although the nozzle is closer to the target (good) the benefit of air assist has been greatly reduced (bad). Air induction nozzles might help on boom extensions, per below.
Wet booms can be extended to reach high canopies, but may no longer benefit from air assist. Consider using air induction nozzles in these positions.
Air Induction Nozzles
Consider using air induction nozzles in the top two positions of each boom (totaling four per sprayer), with or without towers. There are three advantages:
1. Coarser droplets have more mass. They move in straight lines and are less likely to be deflected by wind before they reach the target.
2. Coarser droplets can be propelled by pressure, so unlike finer droplets they rely less on being carried by sprayer air.
3. Coarser droplets that miss the target do not continue upwards; they fall back out of the air into the orchard, reducing off-target drift potential.
No matter which strategy, or combination of strategies, you use to hit the top of the canopy, always confirm coverage using water-sensitive paper. Further, recognize that it’s very difficult to compete with high winds, so know when to wait it out.
Controlling your spray at the top of the canopy means better coverage and less waste. Plus, people won’t see this (wait until the ~50 second mark).
April 18, 2016
Hol Spraying Systems – Canadian airblast gets an upgrade
The first modern airblast sprayer was developed in the mid 1900’s, but competed with existing equipment before it was adopted by the majority. As you can see below, we’ve come a long way. As application technology continues to evolve and grow, so does the array of choices facing growers.
An Ontario orchard spray crew c.1910. Pump pressure was maintained by the two operators at the right. The spraying rate by the above method could cover 1.2 to 1.6 hectares (3 to 4 acres) per hour. Image from www.farms.com
Provide Agro (a subsidiary of N. M. Bartlett Inc.) had been considering introducing a new airblast sprayer to Canada for more than ten years. After deciding not to get into the manufacturing game, they explored importing sprayers from Europe and Australia. In late 2014 they recently invited me to see their choice: the H.S.S. CF airblast sprayer built by Holland-based “Hol Spraying Systems”.
It’s not often I get to see a “new” airblast sprayer design. To be fair, H.S.S. has been building similar sprayers in Holland for more than 20 years, so technically it was new-to-me.
We met at a local apple orchard in Simcoe, where we ran the sprayer through a series of light duties. The first thing we did was explore the sprayer’s features, both optional and standard. As the ambassador to Canada, this particular model had all the bells and whistles. Here is a list of features and observations I feel are worth relating. It’s important to note that this list is in no way an endorsement, nor are any omissions intended to be a condemnation.
The H.S.S. CF sprayer. Outwardly this PTO-driven sprayer appears very different from Ontario’s typical fleet of airblast sprayers. Notably the flexible ducts and gantry comprising the tower, and the double axle. However, it operates using the same principles as our more familiar sprayers and following a brief inspection of welds and fastens (and given its more than 20 year history in Europe) it appears to be very durable.
Each duct is paired to a nozzle body, and that means each air outlet can be adjusted individually. The tower structure can be customized to match everything from vines to high-density orchards and even has an optional woolly aphid attachment for directing air and spray up-and-into the canopy. For taller crops like hops and semi-dwarf trees, a second fan can extend the tower to 5.5 m.
Anyone that’s been stuck in wet weather can appreciate the value in this adjustable double axle. Weight is distributed to reduce compaction and hopefully, the creation of ruts. This feature is standard, but you have the option to upgrade to hydraulic adjustment. I’m not sure how often an operator would want to adjust the axle length, but there it is.
The H.S.S. CF has a lot of features that promote operator safety by reducing the potential for exposure. One convenient feature is the access port separate from the tank fill port. No need to remove the basket to examine/clean the interior, and no need to remove the basket and come in contact with (potentially) concentrated pesticide residue.
Many large field sprayers feature tank rinse nozzles to facilitate sprayer cleanout following an application. Finally, airblast can boast this feature as well. The 150 L clean water tank supplies enough water to the tank rinse nozzles for a triple, low-volume rinse in the field with no need for a pressure washer or a nurse tank. This prevents residue buildup and reduces operator exposure – and it’s standard!
An optional feature is the tank level sensor, which can be tied to the agitation. If you are using a foamy tank mix, agitation won’t turn on until a preset tank level. I’m not certain about this option because proper tank suspension requires agitation from the beginning – just use a defoamer. Note the tank basket has a hose attached to the bottom… read on.
There’s a standard hydraulic jet at the bottom of the tank basket to assist in proper mixing. I don’t know if it precludes mixing a slurry, or if it will improve pesticide bag dissolution, but I have to assume it helps. I trust there’s a safety feature to prevent this nozzle from operating while the hatch is open, but I’m not certain.
This final standard feature may seem small, but it further reduces the potential for operator exposure. The onboard clean water source is separate from the spray tank and the tank-rinse supply and provides a convenient hand-wash station.
Other features include solenoid shut-offs for boom sections, a rate controller and a small-radius draw bar.
An important function of any airblast sprayer is air handling. Too often, tower sprayers have inconsistent air speeds (and presumably air volumes) over the length of the air outlet. Sometimes this can be compensated for using the small deflectors in the tower, or in extreme cases, replacing conventional hollow cone nozzles in “dead spots” with air induction hollow cones that produce coarser droplets and tend to fly farther under pressure. Using a Pitot meter, we examined the airspeed from each air outlet. The PTO was set to 400 rpm and the fan gear was in low.
Nozzle: Ground 2 3 4 5 6 7 Top
Left 70 mph 85 mph 90 mph 85 mph 80 mph 85 mph 80 mph 85 mph
Right 75 mph 90 mph 90 mph 90 mph 80 mph 90 mph 85 mph 85 mph
There were no obvious dead spots, and the left and right sides of the tower seemed about equal. The bottom two positions were notably slower than the rest, but given the distance to the target in that position, and the fact that ambient wind is slower at the ground, it’s interesting, but not necessarily a concern.
We arranged a set of water-sensitive targets in the canopies of semi dwarf apple trees to get a sense of the sprayer coverage. Admittedly, it was very humid and there was little wind that day, so coverage is much easier to achieve because so little spray evaporated or was blown off course before reaching the target. We ran different combinations of PTO speed and fan gear. These images are from 540 rpm and low fan gear using red Albuz nozzles (1.5 L/nozzle/minute @ 6 bar) spraying about 400 L/ha at about 5 kph. On a drier and windier day, higher volumes would be needed.
There were no obvious misses, even when papers were oriented parallel with the ground (exposing their narrow edge to the sprayer, such as in the paper on the right). This isn’t conclusive, but it does show that the sprayer had no trouble penetrating the canopy, and with further tweaking should be able to provide suitable coverage throughout the canopy. Personally, given the upward orientation, I would use the woolly aphid nozzle for all applications, particularly for drenches. More on that later.
One notable quality was the “quiet” operation of the sprayer. Applicators are familiar with the loud whine created by most airblast sprayers; at lower rpm’s and in low fan gear, the tractor seemed as loud (or even louder) than the sprayer operation. You can watch a video of one of the spray passes at the bottom of this article.
So the big question: “How much?”. You’ll have to contact the dealers to find out more, but I will say that stripped down to standard features, it’s comparable to some of the more expensive sprayers in Ontario. Don’t be dissuaded because I believe the expense is warranted given the features, with particular note of the on-board tank rinse system and adjustable air ducts.
So is this the sprayer for you? Well, if you’re in the market for a new sprayer, always start by prioritizing your goals. Perhaps work-rate is a priority, so look to sprayer capacity to reduce the number of refills and consider over-the-row technology (where possible) to reduce the number of passes. Perhaps the crop is adjacent to sensitive areas or residential homes and drift control is a priority; consider adjustable air direction and adjustable air speed.
When compiling a prioritized list, reflect on the positives and negatives of your current sprayer and talk to fellow growers about their experiences. It may come down to personal preference, but consider the following points. These points are in no particular order; they come from many articles I’ve read on the subject of considering new equipment purchases and from talking to dealers, mechanics and sprayer owners:
- Necessity – Is a new sprayer really needed? Manufacturers have a number of retrofit kits available to upgrade and improve sprayers. If poor pesticide performance has led to the decision to purchase a new sprayer, be sure it’s related to the technology, and not to an operating error.
- Crop Type and Acreage – Consider the size of the operation and the size, shape and density of the crop(s). Can the sprayer adapt to provide adequate coverage throughout the growing season and in the long-term? How flexible is the sprayer when spraying different products onto different targets?
  • Sprayer Capacity and Filling – Fewer refills means a higher work rate, but increased capacity also means more weight, so consider the effects on navigation, turning radius and soil compaction. Is the tank easy to fill?
- Cleaning, Calibrating and Maintenance – Moving between crops sometimes requires complete cleaning and decontamination of the tank, lines, nozzles and any shrouds or ducts. Clean water reservoirs, tank-rinsing nozzles and overall accessibility should be considered. Review the steps required to winterize and to calibrate the sprayer. Is it easy to access parts? Is operator exposure minimized
- Horsepower – This is an important consideration for airblast sprayers because fans move a lot of air and liquid. Tank agitators require power, too. Consider selecting from the higher range of manufacturer-recommended horsepower to improve longevity. Remember, however, that fans typically don’t have to operate at the maximum rated rpm’s, particularly early in the season.
- Nozzle Technology and Operating Pressure – Consider the range of nozzle-types intended for use and ensure the sprayer can provide sufficient pressure. While more expensive, diaphragm and piston pumps have fewer moving parts in contact with the spray solution, reducing cleaning time and operator exposure.
- Spraying Conditions – A sprayer has to be reliable, even in adverse conditions, so consider the operating environment. Night spraying, uneven terrain, high winds, dry conditions – many environmental factors can impact sprayer performance and may warrant special consideration. Investigate deflectors, shrouds and the structural framework and durability of the sprayer.
Since its introduction in late 2014, growers have been slowly adopting this sprayer in Ontario and the northern US. Some high-density operations have purchased the optional over-the-row boom system that allows them to spray multiple rows at once. Here at at the Simcoe Resource Station, we’re hoping to run the HOL sprayer in apples for the 2016 season to see if the optional woolly apple aphid (WAA) nozzle has any impact on scale, mites and of course, WAA control. Moreover, we plan to run that nozzle all season long to see if its upward angle improves underleaf coverage and canopy penetration.
April 8, 2016
Continuous Rinsing
We’ve recently been talking about how to save time while cleaning a sprayer. Although it’s very important to be thorough while cleaning, and to take the necessary time to do the job properly, there is always an opportunity to fine tune and spend less time. This is especially true when diluting the tank remainder down and pushing clean water to the booms. A method promoted in Europe, and coming to us via Joachim Herfort of Agrotop, is called “Continuous Rinsing”.
Continuous Rinsing requires a dedicated pump that delivers the clean water (which may contain a cleaning adjuvant) to the tank via wash-down nozzles. It works like this:
1. The operator, having carefully measured the pesticide mixture, has only a small remainder in the tank when spraying is complete.
2. This remainder is sprayed out in the field, either on a set-aside area, or over the already sprayed field at a reduced rate, product permitting (the operator would pay attention to crop tolerance and carryover issues)
3. As soon as the tank is empty, indicated by the boom spray pressure dropping, the operator switches on the clean water pump which delivers the clean water via the wash-down nozzles.
4. Soon, the main product pump starts delivering the wash-down liquid to the boom and the return lines.
5. Because the clean water pump will deliver less than the boom flow, the cleaning mixture is delivered somewhat intermittently. We are told that this helps with the cleaning action of the lines. Be cautious that the main pump does not run dry long enough to damage its seals.
6. Once the clean water tank is empty, the pressure drops again for the final time and the tank rinsate is now very dilute.
7. Testing in Europe has shown that the whole process takes only about half as long as batch mode. One key time-saving feature is that the sprayer never has to stop, and the operator never dismounts. These data also show that a significantly lower water volume is required to achieve a greater dilution of the remainder than a batch mode would have achieved.
8. For example, the European tests (we believe these were done by the Landwirtschaftskammer of Nordrhein-Westfalen, a German regional government) used a single rinse of 80 L, as well as four batch rinses of 20 L each. As expected, the four-batch process was superior to the single rinse, but took a lot of time. They then tested a continuous rinse with 40 L. The continuous rinse resulted in greater dilution than the 4 x 20 L rinse, in less time. In this case, the quality went up, and the time went down.
Our challenge in North America is to roughly match the clean water pump, wash-down nozzles, and main sprayer pump capacities so the system works. Our larger sprayers easily deliver 30 gpm, and some adjustments may be necessary.
Dilution of the tank remainder is only one aspect of sprayer cleaning. The other aspect, decontamination of surfaces and components, is also important and the process depends on the active ingredients and formulations in the tank.
An animation developed in Germany and shared via Agrotop is available here.
Note that Agrotop has suggested components to convert a sprayer to a continuous rinse system here.
March 22, 2016
Top Sprayer Retrofits
You’ve got an older sprayer. Your neighbours have newer sprayers. For various reasons, you’ve decided against a trade. How can you still get the benefits that newer sprayers deliver? Let’s explore how to improve your sprayer performance and productivity with strategic component upgrades.
Most of the biggest gains will relate to the plumbing, especially filling and cleaning. Here is a list to think about:
Nozzles. This one’s a no-brainer. Nozzles remain the cheapest and most important part of any sprayer, affecting coverage, drift, and accuracy. Although durable, nozzles do wear or get damaged over time. But perhaps more important is the changing use patterns of our pesticides. We are moving into a time of greater reliance on tank mixes that blend systemic and contact products, and also higher water volumes into mature canopies. For example, fungicides for Fusarium Head Blight benefit from twin fan nozzles. We’re also seeing new herbicide registrations with greater spray quality (droplet size) restrictions, requiring coarser sprays or higher water volumes to maintain acceptable drift amounts. Are your nozzles able to meet those needs?
Nozzle bodies or turrets. As we move towards more specialty applications, perhaps we need a greater selection of nozzles at our disposal at any given time. Bodies with 5-nozzle turrets are standard on newer sprayers, and these make sense. Burnoff, in-crop, fungicide, and fertilizer nozzles are four that most users will need just from flow-rate needs alone. But some finer or coarser options of each may also be justified, and easy access saves time in the field. New bodies also provide new seals, and the newest offer higher flow rates and exchangeable parts.
Boom end cleanout. Removing residue or air from booms is an important part of good practice. Many sprayers already have manual valves that allow this to happen relatively easily, but it’s still a process that an operator has to make time for. And on top of that, flushing boom sections results in massive doses of pesticide on the soil. One of the most innovative inventions in recent times is Hypro’s Express Nozzle Body End Cap. A DIY or dealer installation of these units allows your boom to bleed introduced air on the go. The ENBEC also forms a dead end exactly at the last nozzle position, eliminating the dead spots that introduce contamination after a pesticide switch. Cleanout and shutoff response also improves. A fast boom flush is straightforward by moving the turret to an open position. TeeJet offers a Rapid Stop extended inlet tube that evacuates trapped air from the wet boom, can be retrofitted on most bodies. Wilger Combojet bodies offer a similar design called Kwikstop. Both can be expected to improve shutoff response, but do not address boom end contamination.
Wet boom. Are your wet booms made of plastic? If so, they can warp over time and are also harder to clean. Replacement wet booms are available from several suppliers, including Hypro and Wilger. These are made of thin-walled stainless steel for excellent durability and ease of cleaning. Wilger units are very thin and light and come with their own Quick-Nut fittings and feature swept elbows and Ts. Hypro’s Express Booms come with nozzle bodies and Express Nozzle Body End Caps. Flange fittings are used in the Hypro upgrade.
New boom. Some people are recognizing the value of boom width in sprayer productivity and are considering a wholesale boom replacement from a third party. These booms come in wider sizes, lighter materials such as aluminum or even carbon fibre, and innovative plumbing options such as recirculating designs or telescoping for adjustable widths from 80’ to 150’. Perhaps a better suspension system or automatic boom levelling system is part of such a purchase.
Individual nozzle shutoff. Most sprayers have sectional control of at least 5 sections. But some of the outer wings (the part of the boom that is most often involved in sectional control) can still contain significant lengths tied to a section, creating waste. With individual shutoff valves, a boom can be converted to either many smaller sections or even nozzle-by-nozzle sections, depending on the capabilities of the rate controller. Not only do these offer excellent resolution, they also feature instant shutoff and turn-on response at the spray pressure. Because this type of installation can demonstrate product savings, it has a calculable ROI.
Rate controller. Some older sprayers struggle with responsiveness. An operator changes speed, and has to wait a long time for the rate controller to catch up. A newer controller can improve the responsiveness significantly, offer a new larger cab screen, work better with a navigation system, or even include ISO-BUS capabilities for future upgrades. Improving the user experience with a better interface can be valuable, giving an old sprayer a new capabilities and feel.
Variable rate technology. We are seeing several options that can offer better control over nozzle flow rate to suit either a greater range of travel speeds (on hilly or otherwise uneven land) or a better range of rates for prescription map application. Pulse-Width Modulation systems from Capstan (Sharpshooter) and Case (AIM Command), Raven (Hawkeye), or TeeJet (DynaJet) all offer these types of features. A new nozzle body, Hypro Duo React, achieves similar results with multiple nozzles that can switch back and forth according to flow rate needs.
Boom lights. Whether spraying at night or wishing to see spray patterns better in the day, boom lights can help. Versions are available from ATI or SprayTest. Caution is advised when spraying between evening and morning hours, as temperature inversions are common during that time.
3″ plumbing. One of the biggest productivity tools is decreasing the time required to load a sprayer. Wide booms applying large water volumes at fast travel speeds can empty even a large tank in 30 minutes or less. If the fill also takes 30 minutes, then 50% of the spray day is spent idle just for filling. Increasing the fill speed with a new load system using 3” plumbing and a high capacity pump can reduce that to 10 minutes, adding acres per hour. Make sure, though that dry products are properly hydrated so they mix well and stay out of screens. Also consider the rate of chemical induction, as that can be a bottleneck.
Tank wash down nozzles. These nozzles, installed at the top of the tank, direct a clean water source (containing a cleaning adjuvant if needed) to the tank wall, rinsing the pesticide off. Successive batches of cleaning improve the tank wall decontamination as the solution becomes more dilute. By making the wash down easier, tank cleaning can occur in the field immediately after spraying and the rinsate can be sprayed out in the field. This saves time and prevents point-source contamination.
Self-cleaning line strainers. Consider this a productivity tool. Mounted on the pressure-side of the pump, these strainers use excess pump capacity to bypass particles back to the tank. A tapered design creates a rapid flow of liquid past the screen face generating continuous wash-down of particles. Regular inspection is still recommended, but the chance of a problem is significantly reduced. Because debris is returned to the tank, proper tank sump cleaning becomes more important.
Pump. Some call it the heart of the sprayer. The pump pressurizes the spray mixture so it can be distributed evenly and atomized. To do this, it needs to produce high enough flow for our ever increasing water volumes, travel speeds, and boom widths, while maintaining enough reserve for agitation. Some use the system pump to draw water into the tank, which can present a bottleneck. Clearly, capacity and pressure are important. Pump impellers can wear and seals can leak, reducing performance. New or re-built pumps are available in long-lasting stainless steel, and the best new models have flange fittings and seals with either enhanced dry-run survivability, or dry-run capability. An upgrade definitely worth considering.
Clean water tank with dedicated clean water pump. This is another productivity tool. Cleaning the tank in the field without stopping the sprayer becomes an option with this design. Rather than use the product pump to draw clean water into the tank, mix it up, spray it out, and repeat, this design allows continuous cleaning. When the product tank is empty (signalled by a loss of pressure), the clean water pump turns on and delivers clean water through the wash-down nozzles. The pump must have enough capacity to obtain a good cleaning spray from the wash-down nozzles. As the sump fills again, the product pump delivers it to the boom and also cleans the return lines. The end result is prompt cleaning of the tank and thorough, efficient dilution of the remainder.
Boom remote control. Whether it’s for cleaning out boom ends or simply verifying proper nozzle operation, a remote boom section shutoff makes those jobs easier, safer, and more environmentally friendly. Boom remote controls let you turn on just the boom section you need to inspect. It’s also useful for nozzle calibration.
Tires. Ask yourself: what equipment do I spend more time in than any other, makes more passes over each field than any other, makes deeper ruts than any other, and gets stuck more often than any other? A new set of tires, or even tracks, might be worth considering. Low-pressure sprayer-specific tires with VF (Very High Flexion) technology are available from major suppliers. These offer sprayer-specific lug designs, they increase the footprint for increased floatation and less compaction, and they can also improve ride quality. Tracks, though considerably more expensive, are becoming available for sprayers and can make sense in some situations.
Some of these retrofits can be costly. But they can introduce new life and utility into an aging chassis, resulting in higher productivity, higher quality work, or simply a better operator experience. All of these are important and are worth investing in.
Here’s a Real Agriculture video of Tom and Jason talking sprayer retrofits at the end of Edmonton’s 2016 FarmTech.
Note the snazzy “Sprayers101” team shirts!
February 21, 2016