Since tribostatic spraying and high-voltage electrostatic spraying have different charging methods and form different electrostatic fields , they show some unique advantages , mainly as follows.
1. Save equipment investment
Since the tribostatic spraying is mainly charged by the friction between the powder coating and the gun body, there is no need to rely on a high-voltage electrostatic generator to charge the powder particles, so the investment in an electrostatic generator is saved.
2. Eliminate hidden dangers of accidents
Since there is no metal electrode in the friction electrostatic Spray Gun, there will be no accident of spark discharge caused by short circuit between the electrode and the workpiece during the spraying process, thereby eliminating the hidden danger of burning and explosion in the coating field.
3. Easy to operate
Because there is no need to connect high-voltage cables, the Spray Gun can move in a large space, and the changes of various process parameters have little effect on the spraying effect, and similar spraying effects can be obtained.
4. Wide application range
Especially for small workpieces and workpieces with complex shapes, better spraying effect can be obtained by using tribostatic spraying.
5. No powder accumulation in the Spray Gun
Since there is no metal electrode in the friction electrostatic Spray Gun, there is no phenomenon of powder accumulation on the electrode, which avoids the disadvantage of spit powder during spraying, and ensures that the surface of the obtained powder layer is smooth and flat.
6. Can spray thicker coating
When the powder layer of high-voltage electrostatic spraying exceeds a certain thickness, more and more negative charges are accumulated in the powder layer, and the electric field strength becomes larger and larger until it rises to the strength of being broken down, so that the coating deposition layer is destroyed and localized corrosion occurs. If the insulation is broken down, "snowflake"-shaped depressions and pits will appear on the surface of the coating. However, there is no high-voltage electrostatic field in the friction electrostatic spraying, so the reverse ionization phenomenon is not easy to occur, and thicker coatings can be obtained.
7. High powder deposition efficiency
Especially in the case of small spraying amount and short-distance spraying, the powder deposition efficiency of friction electrostatic spraying is higher than that of high-voltage electrostatic spraying. Although the adhesion of the formed powder layer is not as good as high-voltage electrostatic spraying, it still has enough adhesion to meet production line spraying requirements.
However, there are also some deficiencies in the friction Spray Gun, mainly in the following aspects:
1. Short service life
Because static electricity is obtained by friction between the powder coating and the gun body, the gun body is greatly worn during the electrification process. In order to ensure a better electrostatic effect, the gun core of the friction Spray Gun must be replaced frequently, so the life of the friction Spray Gun is shorter than that of the high-voltage electrostatic Spray Gun.
2. Applications are limited
Unlike the high-voltage electrostatic Spray Gun, which can be used for various powder coatings, it can only be used for powder coatings that can produce better frictional electrification effects. Powder coatings such as polyethylene cannot be sprayed with a friction Spray Gun due to poor frictional electrification effect.
3. Insufficient charge of the powder
Compared with the high charge of the high-voltage electrostatic Spray Gun, the charge of the friction Spray Gun is small, so the adsorption capacity of the friction-charged powder coating on the workpiece is low.
4. Strict requirements on the environment and gas source
The use of tribostatic Spray Guns has higher requirements on the temperature and humidity of the environment, high humidity and low frictional charge, and the charge is prone to leakage. It is required that the content of impurities such as moisture and dust in the air source is low, otherwise it will affect the friction electrification effect and the spraying efficiency of the powder coating.
These factors limit the use of tribostatic Spray Guns.
