Overview of Electrostatic NDT

An electrostatic nozzle is a simple yet effective electrostatic system that works in coating rows of plants and row crops with electrically charged metallic particles of pesticides such as a ground nozzle body for application onto a row of crops or rows of plants. These are used both to protect the coating from damage and to prevent moisture from entering into the rows. The coated areas will be protected from the effects of weather in the area has been treated to prevent moisture. The application and result are a protected coating that will withstand the effects of weathering and the chemicals contained within the pesticide.

Electrostatic Nettings are not just used on crops but can also be used for lawn sprinklers and garden drainage systems as well. They can also be found in sprinkler valves for your outfeed system, so that when the spray nozzles are turned off the spray nozzles automatically stop spraying when the valve is released. This feature gives you a very consistent, reliable spray without any possibility of inconsistent spray coverage.

Electrostatic discharges occur when the stream or spray moves too fast through an area or charge of conductive material. An electrostatic discharge occurs when the charge of the electrostatic charge diffuses into a medium at or near its point of origin creating a field that is electrostatic. The diffused charge travels from point A to point B where it causes the electrically charged particles in that medium to become excited. This excited state of the particles produces a rapid discharge of energy, which is why the area it is sprayed in or around is referred to as the electrostatic field. If a medium does not contain evenly distributed electrically charged molecules they too will become excited and produce an electrostatic discharge.

The flow of particles in an electrostatic discharge system is controlled by the variation in voltage between the conducting elements. By varying the voltage between the cells, varying the strength of the electric field, and varying the distance of the spray droplets between them all we can control the behavior of the system. The goal is to have the smallest amount of electrostatic charge diffuse into the area being sprayed so that the greatest amount of charged particles can be scattered off target surfaces. This surface area is called the Electrostatic Zone. The size of the zone will depend on the size of the target surfaces and the variation in voltage.

In electrostatic nozzle assemblies the flow control is obtained from a separate air passageway fitted to the top of the unit. On the assembly’s bottom side, a cover assembly is fitted with a disc to act as an electrode. As the unit flows through the assembly, the discs are evenly coated by the varying voltage and air flow. When the unit is finished, the cover assembly is removed and the nozzle assembly can be removed. The assembly is now ready to be used to coat objects comprising the Electrostatic Zone.

The simplest way to demonstrate the invention is by using a small amount of static charge produced by the nozzle body and passing air into the chamber. By varying the depth of the spray jet and varying the tension of the armature, the charge produced can be varied within limits sufficient to demonstrate a wide range of deposition products. By selecting a high tension armature having a low center line, we will achieve a very fine deposition line on a flat, smooth and even surface. This allows us to build up a large positive static charge on the bottom surface of the object. The attraction of this technique is that the electrostatic nozzle body assembly can be switched out for a different armature arrangement in cases where the desired effect is different. For instance, if we wish to build a larger positive charge on the bottom surface of a round object, we can opt to switch the electrostatic nozzle body from a one-cell unit to a two-cell unit housing; or if we wish to build a smaller positive charge on a flat surface such as a sphere, then we can switch the nozzle housing from a two-cell unit housing to a one cell unit housing.

To conclude, it would seem that there are at least three basic ways by which the electrostatic spray device can be utilised. Firstly, the two techniques described above can be used to build up small positive charges on flat and smooth surfaces, and these charges are stored in the rotating discharge assembly until released by the air stream into the working chamber. Secondly, the three techniques can be used to build up quite a large amount of charge on the bottom surface of an object. The final way in which the invention can be utilised is to build up a fairly stable charge on the surface of the object. This charge is discharged into the air stream and the swirling motion of the discharge assembly brings the charge down the discharge path into the work chamber until it again drops back into the work chamber below.

The discharge method described above demonstrates that the invention is capable of providing a dynamic flow of negatively charged droplets, where the droplets may interact with the target surfaces. It also demonstrates that the invention provides for a positive charge to be formed on the flat surfaces by interacting with the positively charged ions present in the droplets and with the negatively charged surfaces on the target surfaces. This interaction results in a release of the emitted liquid droplets and a subsequent release of a stream of negatively charged ions into the air stream where the droplets collide with other particles in the air stream or the target surfaces and emit droplets.