The use of heat energy in the powder coating process

Additional information on heating

When choosing a furnace, all its variable parameters must be taken into account, among which the most important are the following:

furnace equipment: furnace type, shape, dimensions, heating system, operating temperature, heat transfer, ventilation, safety at work;
transport chain conveyor: type, feed rate, work load, shape of the hangers, and the system for attaching the painted parts to them, productivity;
parts to be painted: are a determining factor affecting the adhesion of the polymer film, the consistency of color and gloss of the coating surface;
powder paint: type, coating thickness, color, gloss, polymerization parameters, special conditions.

Compliance with safety standards

When installing the oven in a production area, make sure that it fully complies with safety standards.

The first thing worth paying attention to is the operation of the hoods, the fan, as well as serviceable sensors, which will immediately signal any anomalies in the inflow of fresh air.

Infrared ovens

Infrared heating takes place using IR lamps. This oven is widely used in a continuous painting cycle.

For example, in the case of painting oil filter housings, panels, strip or steel products.

Often this type of heating is used in conjunction with a conventional burner system in order to: reduce the need for production space, speed up the production cycle, or compensate for insufficient heating on existing equipment.

Typically, IR elements are installed at the entrance of the oven to accelerate the reflow of the applied powder coating. This helps to avoid partial deflation, which could lead to contamination of the interior of the furnace or production hall.

Heat energy is generated in different types of ovens and is used in powder coating for a wide variety of applications. Thermal energy is used to preheat porous castings before painting in order to rid them of various gases that may remain on the surface of the parts.

Also, it is necessary before heating the part before painting, before painting using the fluidized bed method, or for additional heating of an already painted part. This is necessary in order to improve the relaxation of the polymer coating.

In addition, the heat energy is used to dry the parts after they have been washed and rinsed during the surface preparation process for painting.

Preheating painted parts

When necessary, it is used to dry parts that have gone through a cleaning and surface preparation cycle. Usually, furnaces of simple design are used, due to the low operating temperature (50-90 C) with limited ventilation inside, due to the fact that there is no need to remove a significant amount of vapors.

The higher the temperature of the part, the thicker the powder layer will form on its surface, before the temperature of the part drops below the melting point of the base polymer of the powder.

Additional heating of the painted parts

The final operations associated with the polymerization of a powder coating are one of the most difficult processes.

The furnaces used for these purposes are intended for the production of thermal energy, it is necessary for melting the powder applied to the surface of the parts at normal ambient temperatures, spreading the resulting gel and its subsequent hardening. Since in this case we are talking about the strict constancy of the temperature regime throughout the entire internal volume, then the furnaces must be equipped with air filtration systems. It is also important to observe the speed of the temperature regime in the oven. After all, this indicator affects the thermal expansion of the polymer oven.

Important! If you want to achieve stable quality and uniform polymer coating, then you need to observe the stable operation of thermal equipment.