Sprayer Care

Spraytech sprayers are designed to spray a large variety of Agricultural and Lawn & Garden chemicals diluted in water.  The pumps do not pressurize the tank, but actually draw the solution from the tank and pressurize the sprayer's plumbing system.

Piston and check valves inside the pump create the suction to draw the water from the tank and then force the water through the discharge port of the pump.  On basic spot sprayers, the only pressurized plumbing is the 15 foot of hose and the handgun.

High-Flo Gold Series pumps used on Spraytech sprayers are "demand" pumps that only run when there is an open outlet for the spray.  When the lever on the handgun is squeezed to spray, the pressure in the plumbing drops and the pump will run.  When the lever is released, a pressure switch located on the pump head senses the pressure increase and shuts the pump off.  The pressure switches are preset at the factory and are different for each of the three different sized pumps.  Some Spraytech sprayers are equipped with a pressure gauge and bypass valve.  On these units, the pressure at the spray tip can be regulated by opening or closing the bypass valve.  Opening the valve reduces the pressure by diverting some or all of the spray back into the tank.  Highest pressure is achieved by having the bypass completely closed.

12 Volt Pump Basics & Repair

Spraytech uses 12 volt diaphragm pumps on its sprayers.  These pumps utilize pistons that vibrate back and forth in a sealed chamber.  As the piston moves away from the check valve assembly, it creates a vacuum that draws the spray past a check valve into the chamber.  As the piston moves back toward the check valve assembly, it forces water through vents and out past a second check valve.

12 volt pumps are rated at "open flow".  This rating is the amount of water that the pump can move dumping out of the discharge side of the pump with no restrictions.  Pressure is created by restricting the flow by means of the tips on the boom or the adjustable tip on the spray wand.  Therefore the actual output will be reduced from the rated capacity.

Gold series pumps are designed to spray a large variety of Agricultural and Lawn & Garden chemicals diluted in water.  They are not built to pump petroleum products such as diesel fuel, kerosene or gasoline.  Pumping these products will lead to pump failure and will void the warranty.  Additionally, you should never use these pumps to pump any flammable fluids. The motors are not sealed and could ignite flammable vapors, causing injury or death.  Other materials to avoid are bleach, paint and stains.

Spraytech recommends that you purchase and spray liquid formulations of pesticides.  Wettable powders, soluble granules, and other dry formulations will not always dissolve completely and can either plug the strainer or build up inside the pump, causing it to fail.

If you must use a dry chemical formulation, you should first use a separate container to form a slurry that can be added to the water in the tank and then mixed.  The proper mixing procedure is to fill the tank ½ full and then add and mix the chemical and then fill the tank the rest of the way.

If yours pump starts to lose pressure or you notice a decrease in flow, check the strainer to see if it is being clogged by foreign materials. 

When you are done spraying, you should fill the tank part way with clean water and spray clean water out the handgun and boom.  Refill the tank ½ full with plain water and use a chemical neutralizer or Cleaning Agent and repeat the cleaning process.  Spraytech also recommends that you not mix more spray than can be sprayed in a day and that if you have leftover spray in the tank that you still rinse the pump and plumbing.

At the end of the season, clean the sprayer a final time and drain out all of the water paying special attention to the pump, handgun and valves.  Then winterize the sprayer by pumping RV antifreeze through the entire plumbing system.

Spray Tips

Spraytech uses two different types of spray tips on its boomed sprayers.

Two nozzle booms are used on the ATV-15-2, ATV-20-2, 15 through 30 gallon trailer sprayers and ATVBK-200 boom kit.    This boom uses "flood jet" tips spaced 40 inches apart.  They spray a very wide angle pattern with a course droplet.  They work well with common broadleaf weed killers and lawn insect control chemicals.

The five nozzle and larger booms use "flat fan" tips spaced 20 inches apart.  These tips will still work with the previous chemicals and will provide a finer more even spray pattern.  They work better when you need a more thorough coverage for fungicides and some less common weed killers.

The actual amount of spray applied is a combination of pressure and driving speed. 
****The faster you drive, the less spray will be applied.  The slower you drive, the more spray will be applied. 
****The lower the pressure, the less spray will be applied.  The higher the pressure, the more spray will be applied. 

The owner’s manual for your sprayer will have a chart to help you calibrate your sprayer.

CDA Spraying In Glass Houses

The greenhouse environment is unique and demands crop-spraying strategies altogether different from those adopted in the field. Nowhere are higher-value crops grown so intensively and biological control, employing programmed release of predators and parasites, used so widely. The luxuriant growth and densely packed foliage of a healthy greenhouse crop may pose several problems related to the safety and efficacy of water-based sprays using traditional high volume hydraulic sprayers.  Foliage, already susceptible to moisture related diseases such as Botrytis (gray mould), is made more so by the effects of water-based sprays applied by in high volumes. It is difficult to obtain efficient coverage without the use of air-assistance and operators find difficulty moving unhindered and uncontaminated between rows of greenhouse grown crops carrying bulky knapsack sprayers. Requirements are for targeted sprays using low doses of pesticide formulated in non-aqueous carrier liquids or the minimum amount of water. Air assistance is essential to give droplets added momentum and to open up the canopy for efficient coverage. 

Micron Sprayers, designer of innovative spray application techniques provides a range of hand-held air-assisted ULV sprayers dedicated to greenhouse application. The sprayers, which include mains-powered (Turbair Electrafan 110/240) and battery-operated (Turbair Electrafan 12) models, are used to apply pesticides, growth regulators and fertilisers to greenhouse crops throughout the world. Growers in the Netherlands, which has one of the biggest and most innovative industries, use large numbers of these sprayers either off the shelf or in units custom-designed for their own greenhouse spraying requirements.  

One recent convert to Micron’s sprayers is Mr A. Van der Valk-Den Drijver, a specialist  grower of capsicum peppers at Honselersdijk, Netherlands. Mr A. Van der Valk, who has been using Micron’s battery-powered 12V Turbair Electrafan sprayer for more than a year, is highly enthusiastic about the machine. “Use of the Electrafan 12 is completely compatible with our strategy to use beneficial insects as the mainstay of the crop protection programme. Agrochemicals are only applied when absolutely necessary and in the smallest effective quantities.  

‘Hot spots’ of fungal infection and pest infestation requiring prompt action do occur, says Mr Van der Valk. The quicker we act the easier it is to eliminate the problem without disturbing the delicate balance between beneficial insects and their insect pest hosts and prey. This lightweight and totally mobile, battery-operated sprayer is ideal for quick spot spraying of pest and disease hot spots around the greenhouse. The air assistance produced by the Electrafan 12 allows excellent droplet penetration into the crop canopy to give good control at dose rates 50% lower than standard”, he said.  

Bunnik Plants of Bleiswijk, growing 3 hectares of nursery stock (pot plants) in an automated greenhouse, have been using 12 Electrafan 12’s simultaneously for two years with just one person in sight. This feat is achieved by the ‘Flying Doctor’, a custom-built robotic sprayer featuring a dozen Electrafan 12’s powered by a large central battery and secured to a remote-controlled frame that moves back and forth above the crop to spray as required. “When the greenhouse was built we invested a large part of our input in the use of environment friendly pest control systems based on predator and parasite release”, says Managing Director Frans Bunnik.  

“Before the spray robot was designed and built we applied 1000-1500 litres of water/hectare, but the ‘Flying Doctor’ does a better job with just 75-100 litres/hectare and up to 70% less pesticide. This offers big environmental safeguards as well as a significant saving on pesticide, he said. These gains have been made by improved penetration into the canopy and superior coverage provided by the narrower droplet size spectrum and air assistance. Even difficult-to-control insect pests such as thrips succumb to the ‘Flying Doctor’. Operation via remote control makes the ‘Flying Doctor’ ideal for spot application that safeguards our beneficial insects, says Frans Bunnik, as well as making life a lot easier for our crop protection specialist.”

CDA Technology

Controlled Droplet Application (CDA) was introduced into plantation agriculture in South East Asia more than a decade and a half ago because it offered significant advantages over high volume techniques for the application of herbicides. These included high work rates, reduced labour costs, improved chemical efficacy and reduced operator contamination.

 In a region of increasing labour shortage all of these factors continue to make Controlled Droplet Application the most appropriate technique for herbicide application within the plantation sector.  Attention needs to be paid, however, to ensuring that the type of sprayer used and parameters of use ensure that the spray atomisation process optimises the efficacy of the herbicide applied.

Controlled Droplet Application

The efficiencies of CDA technology

Most agrochemicals are applied as liquid sprays which are broken up and distributed over the target area.

The secret of efficient spraying lies in even and targeted liquid distribution. Uneven coverage of the target area is wasteful, costs money and results in unwanted and unnecessary contamination of the environment.

Another important factor for achieving the best biological results is the spray droplet size. For most spray applications there are particular droplet sizes which will be most effective. In pesticide application, for example, different pests present different targets depending on their size, location and behaviour, thus different spray droplet sizes will be most effective depending on application.

Pioneered by Micron, Controlled Droplet Application (CDA) produces only the optimum sizes of spray droplet for the particular application. This is achieved by specifically designed spinning disc rotary atomisers which break up the spray liquid very evenly, resulting in a narrow range of spray droplet sizes.

CDA application v Nozzle spraying

In contrast, most conventional spraying machines employ a hydraulic nozzle which involves breaking up spray liquid by squirting it under pressure through a hole. This application method is rather inefficient as it breaks up the spray liquid very unevenly and produces a very wide range of droplet sizes.

Very large and very small spray droplets are both wasteful - the large ones end up on the ground whereas the small ones drift wasting much of the spray and contaminating the environment. This inefficiency means that hydraulic nozzle sprayers have to use much more spray liquid than is actually necessary to do the job. To fetch, carry and spray this extra liquid costs time, effort and money for both the small farmer in the developing world carrying out most jobs manually or the large mechanised western farmer.

The waste and environmental contamination resulting from spraying pesticides through hydraulic nozzles is causing increasing world-wide concern. CDA offers a scientifically-proven solution that improves spraying efficiency, eliminates waste and safeguards the environment.

The efficiency of CDA enables the use of low and ultra-low volumes of spray liquid. This logistical advantage can be of critical importance in crop protection, allowing effective spraying programmes to be undertaken quickly in non-mechanised agriculture and greater spraying productivity in mechanised agriculture. Being able to apply pesticides accurately, quickly and cost - effectively when needed gives the opportunity of fully implementing Integrated Pest Management programmes, with reduced overall pesticide usage.

Advantages

CDA (Controlled Droplet Application) technology offers a wide range of economical and environmental benefits which include:

Operational efficiencies:

• Cost savings due to reduced volume of spray
• Even droplet distribution and uniform droplet size produce better spraying results 
• A considerably faster spraying operation

Increased productivity:

• Considerably less spray liquid is needed compared with conventional sprayers
• Consequently the amount of time and effort required are considerably reduced 
• Hand-held sprayers incorporating CDA reduce physical effort as strenuous pumping is eliminated 

Improved chemical efficacy:

• CDA technology improves target coverage and spray droplet retention  

Safer Spraying:

Significantly reduced operator contamination risk during the spraying process:

• Operator errors due to fatigue are reduced as the process is less arduous than high volume nozzle spraying 
• Fewer mixing and filling operations where operator contamination is most likely

Reduced Environmental Impact: 

• Reduced chemical and water requirement 
• Lower contamination of soil compared to nozzle spraying thanks to low-volume, targeted application