Most often in usage of farmers of Ukraine can be seen mounted, trailed and self-propelled sprayers.
Mounted sprayers are mounted directly on the tractor, so justified in case with a small processing area. They cost less than the others, but at the same time they cannot have a large tank volume. The small price and ability not to purchase additional equipment (provided that there is already a tractor on the farm) - threre are advantages of the mounted sprayers for the agrarian. The disadvantages can be attributed to the small volume of the tank and the dependence on the tractor patency. Simply put, where the tractor does not pass, there is no herbicide applicating.
Self-propelled sprayers are a separate class of agricultural machinery, which is intended for the application of liquid and/or granulated fertilizers. When performing typical work for themselves, they surpass mounted and trailed in performance.
The self-propelled sprayer-spreader «Vodoley» on low-pressure tires does not damage the winter crops in the tillering phase and moves freely even over very damp ground.
Intermediate between them a class of equipment are hook-on sprayers. They are simpler in structure than self-propelled, therefore cheaper than the latter. The power plant is usually not - they are dependent on the tractor towing them. But additional components can be installed that improve the functionality:
That is, for a number of farms trailed sprayers can provide a reduction in operating costs. Less complex design is easier to operate and maintain. Of course, the maximum speed of work is shown by self-propelled sprayers, but if you are going to buy trailed one, this recommendations can be relevant.
Today, more often one can see membrane-piston or centrifugal. First you need to look outside the pump. If the places where the plastic sheeting is peeling off the metal case are visually detected, an overheating point can be suspected at this place, to determine the cause of which, it is worth looking inside the mechanism. The second reason for the peeling of plastic may be the stay of equipment in the cold.
The oil in the oil system must be clean. Blur may be in violation of the tightness of the system. In any case, pump repair will be cheaper than replacement.
First of all, you need to check the junction sections. If cracks are visible, this is not critical, as it can be corrected by welding, (which should affect the purchase price). If the outer sections hang down, this may be due to the wear of the hinge pins. They need to be replaced or supplemented with sleeves made of stainless steel, nylon.
At the same time, it is necessary to assess the condition of the hoses, nozzles (sprayers) on the rod.
Aluminum rods reduce the overall weight of the sprayer, but may increase cost unpleasantly.
Usually to fix the rod the rear frame in the form of a parallelogram or vertical frame is used.
To check the parallelogram suspension, you need to deploy the sections and push one of the sides of the rod up. If the parallelogram skewness is visually detected, it will be necessary to replace the worn elements in it.
The vertical frame can either rust with loss of mobility, or vice versa not to keep the bar at a certain height. In both cases, you will have to change the failed latches.
In most trailed sprayers this part consists of standard components, which can be found in the usual auto shop. This part must be fully functional before entering the field, as it is responsible for the fact of towing the sprayer itself. Simultaneously with the inspection of the coupling device, one can pay attention to the condition of the hoses, tubes, and electrical wiring.
A number of trailed sprayers are equipped with steering mechanisms that change the direction of the wheels of the unit when turning the towing equipment. In European sprayers, these can be Tec or Muller systems. Their main task is to turn the sprayer wheels to the desired angle when turning the tractor. If this is done by an electronic unit, you should check its operation to avoid unnecessary expenses.
Modern sprayer can not do without electronic systems that control a variety of functions. By classifying these systems, it can be said that sprayers with relatively simple control systems or using the CAN data bus can be found on the market.
The second option (CAN) is more expensive, but it is interesting for its scalability and the ability to connect a large number of additional devices that support this communication protocol. But in case of failure of the tire itself, the repair will cost a lot.
Thus, if you see two similar in terms of physical parameters, but strongly differing in price, trailed sprayers, one of the explanations is the presence of an electronic control system on the CAN data bus. If there is a tractor with the same data transmission system, then the purchase can be rational.
Before buying a sprayer it is important to check the operation of the working fluid supply system. For what the tank is filled with water and the outflow starts. At the same time, a visual assessment of all connections, hoses, and valves operating the sections is performed. Normally, motorized valves switch in 0.5–1 second. Next, check the outflow from the appropriate section - if the outflow continue when valve is closed or the shutdown process itself takes longer than one second, then most likely this valve is no longer valid. Moreover, since they all worked in the same conditions, the rest are not much in the best condition.
It is good if it is separated from the rest of the sprayer and can be inspected from all sides. Particular attention should be paid to the seams - there are often cracks. Try to look into the tank to assess the condition of the inner surface. There may be visible cracks that are not visible from the outside. By type of material emit stainless steel, fiberglass, polypropylene.
Stainless steel is strong, durable, heavy. This material is the most resistant to shocks and cooling. If a leak occurs, you can use welding or a conventional hot melt glue gun.
Polypropylene is cheaper, weighs less, but in a few frosty winters it can become overly brittle. In this case, the appearance of cracks is possible, which can be eliminated by welding plastics, for which it is necessary to involve specialists. The result of such welding is not always predictable and it may be necessary to simply change the entire tank, if possible.
Fiberglass tank is easier to repair. If dangling fibers are visible, the inner surface will need to be treated.
Even if according to the result of the external examination it is not possible to find defects, the tank should be filled with water and check its level after a while. A drop in the water level will indicate a leak that can be seen under the sprayer at the same time. If the design of the sprayer does not allow to evaluate the tank from all sides visually, then such an assessment of its condition is simply obligatory.
Some sprayers use pneumatics to turn on and off sections. The pressure in the system is maintained either by a tractor or by its own pump, which requires 12V power supply. Also, the pneumatic system can be used on the suspension rods. Usually, it consists of regular items that can be bought in carshop.
Optional sprayer equipment
Working fluid recirculation through boom pipelines
This system works with individual monitoring of the status of each spray nozzle. Allows you to almost instantly begin the process of spraying for each nozzle (spray) and provides the most uniform distribution of pressure of the working fluid over the entire length of the rod.
GPS entry control
The system described above can be supplemented with a system that, by a GPS signal, turns off individual spray nozzles when the treatment area is overlapped. It work can be seen only by making a test drive.
Automatic boom height control
Designed to protect against collisions with the ground. To check the operation of the system when the tractor is running, move your hand under the height sensor on the rod. Hydraulics should respond properly.