The production of powder coating spray booth is the key process in the spraying production process. The key to the quality of the surface of the sprayed workpiece lies in the control of various process parameters during the spraying process. The amount of powder and atomized air are two key technical indicators.
Before the final powder coating, it can be sprayed several times. At this time, the amount of powder and the uniformity of powder distribution can be observed at both ends of the spray booth. At this time, the powder runs in a straight line within a distance of 10 cm to 15 cm from the end of the spray gun, and the other part is in the form of atomized powder. The powder adsorbed on the surface of the workpiece is actually a powder of such atomization effect, whether the powder with this atomization effect is used as a standard for controlling the distance between the spray gun and the profile. In addition to the process parameters, some necessary small links should also be noted.
1, The location of the spray gun
The spray gun should maintain a certain inclination, biased to the direction in which the workpiece is running. The spray guns are kept vertically parallel in the arrangement, the end portions are kept in a straight line, there should be no overlap between the spray guns, and the positions of the upper and lower spray guns are powdered. It is advisable to cover all the workpieces.
2. Control of fluidized air pressure
The role of the fluidized bed is to use the action of the gas stream to form a proper fluidized state. The hand feel is similar to the state of liquid flow, and the fluidization is detected to a sufficient state. The simplest operation is: when the powder is stirred by hand or a stick I don't feel the presence of resistance. Fluidization facilitates the inhalation of the powder into the catheter, and under the action of the accelerated wind, the effect of atomization is generated. If the pressure is insufficient or the pressure is too large, the fluidization may be insufficient.
3. Recycling of powder
The powder adsorbed on the surface of the profile only accounts for about 1/3 of the powder output of all the spray guns. The powder scattered in the spray booth is more. The recycled powder must be mixed with the newly added powder in an appropriate ratio. The effect is better, so the powder should be Timely recycling and reuse.
4. Closure property in the spray booth
The powder is easily contaminated by external air suspension. After spraying, the surface of the profile is prone to flocculation or shrinkage. After baking, it affects the flatness of the surface of the profile. Therefore, the spray booth should adopt sealing measures to prevent the intrusion of pollutants.
5, The residual powder in the trachea should be cleaned in time, if not used for a long time, easy to agglomerate, powder is easy to produce powder spitting phenomenon, affecting the spraying effect.
6, Spare powder hopper
It can effectively improve labor efficiency when used for powder replacement. The maintenance work of dustproof and moisture proof of spare powder hopper must be done well to ensure the quality of the remaining powder in the powder bucket
7. In addition, the work of replenishing powder should also be paid attention
Although the technical parameters have been debugged before production is normal, the workpiece should be continuously monitored through the powder filling window, and it is found that the powder is shallow and the powder is not adsorbed in time. Since the amount of powder sprayed by the manual rubbing gun is larger than that of the automatic gun, the manual rubbing gun can be speeded up by hand.