Electrostatic Spray Guns And How They Work
An electrostatic spray gun is used in electrochemical applications such as making protective coatings and cleaning equipment parts. A typical electrostatic spray gun works by spraying a conductive coating of electrically charged particles on the surface of the subject material. The high voltage of the electrodial spray can be controlled by altering the strength of the electric field within the spray. When the strength of this electric field is altered, the properties of the coating or other material to be protected become more or less sensitive to the electric field’s intensity.
Electrostatic spray guns are usually employed in applications requiring strong electrical currents; however, it is sometimes possible to find electrostatic guns that use a low or zero current. Typically, nonincendive systems will be operated in environments where a low voltage is needed. It is important to realize that although a nonincendive system may use a low or zero voltage, they are still potentially dangerous in the wrong hands. These types of systems do not provide protection against airborne particles like dust, so a good application practice is to wear a breathing mask while applying these systems. Remember too that if you are using a nonincendive system in a room that contains flammable or combustible materials, you must always have an exhaust ventilation system in place.
Non-voltage electrostatic spray guns work well for spraying materials that are coated with a protective varnish. When a coating material is electrodeposited on metal objects, this coating provides a positive charge; when it comes in contact with a non-voltage surge, the charge is reduced. The lowered charge will then attach itself to the surface of the metal object coating and slow down the transfer process. The coating materials may then be easily picked up and moved from one area to another. This type of application can protect a variety of different materials.
For larger areas, it may be necessary to employ a higher-powered, high voltage electrostatic spray gun. These guns utilize a charging hose and an electrodial charger. The electrostatic charge is then placed in the hose and attached to the appropriate conductive surface. This process allows a much larger area of coverage.
Some of the most popular electrostatic spray gun applications include wood, textiles, fabric, leather and other fine textured materials. A good example of this is the Graco high voltage power brush. Many of the Graco products utilize high voltage power brushes which are able to effectively take care of tough stains, dirt and grease.
These types of electrostatic spray guns require the use of an air inlet pipe that must be connected directly to the electrical source. Then, an air filter figure must be attached to the same pipe. The filter will help to trap particles and dust in the air before they enter the electrostatic power assembly. If the system does not have a filter figure, the air inlet may actually allow particles and dust to enter and create a larger mess.
Figure one will consist of a low resistance spring that contains an electric field that is induced by the applied force. The actual voltage is dependent upon the force exerted through the hose. Figure two will include a flexible hose with a coating on the opposite end. The hose is used to apply the electrical discharge and the coated end of the hose is connected to the charging unit.
Figure three includes a coil that is located inside of a metallic material. As the electrical current passes through the coil, a small but strong electric field is generated. This field is what causes the small amount of current that is picked up by the contact charging component of the electrostatic gun. The coil acts as a conductive link between the metallic charge and the permanent magnet. Once this charge is created, the resulting voltage will depend on the size of the coil.