System for application of powder coatings to electrically non-conductive elements

A system for application of powder coatings to a plurality of electrically non-conductive elements, said system comprising:

• a pre-treating station adapted to coat the plurality of electrically non-conductive elements to provide a plurality of temporarily electrically conductive elements;
• a coating station downstream of the pre-treating station having at least one dispensing nozzle that enables painting powders to be electrostatically applied to the plurality of temporarily electrically conductive elements;
• a polymerizing station downstream of the coating station that is adapted to melt and polymerize the painting powders applied to the plurality of temporarily electrically conductive elements;
• and
• at least one conveyor device extending along a path through the pre-treating station, the coating station and the polymerizing station, enabling transit of the plurality of the electrically non-conductive elements, wherein the pre-treating station is adapted to provide water to be covalently retained on at least one surface of the plurality of electrically non-conductive elements in order to produce an increase of weight in the plurality of the electrically non-conductive elements and causing the plurality of electrically non-conductive elements to be temporarily electrically conductive;
• the polymerizing station adapted to melt and polymerize and being further adapted to eliminate at least part of the water previously retained on the plurality of electrically non-conductive elements by evaporation;
• and wherein the pre-treating station comprises:
• a rack having rollers spaced apart from one another to enable the plurality of electrically non-conductive elements to transit along the path through the pre-treating station;
• said rollers are motorized rollers;
• a plurality of nozzles disposed beneath the rack and spaced apart vertically from the rollers by a fixed distance so that an empty space is created between the rack and the plurality of nozzles, the plurality of nozzles being effective to supply pressurized jets of water that expand in a cone pattern dispersing the water in air due to a drop in pressure in the plurality of nozzles, towards the plurality of electrically non-conductive elements which creates a mist which is a uniform dispersion of water micro droplets in the air all around the plurality of electrically non-conductive elements, the plurality of nozzles being arranged aligned side by side along an aligning direction that is transverse to a forward direction along which the plurality of electrically non-conductive elements move on the rack with the pressurized jets of the water from the plurality of nozzles extending upwardly through the rack, traversing on the rollers, around the rollers, and through each of the spacings between each of the rollers to wet the plurality of electrically non-conductive elements;
• at least one pump operatively connected to the plurality of nozzles;
• and
• an extraction hood arranged to face the plurality of nozzles and the plurality of electrically non-conductive elements, said extraction hood being configured to aspirate the mist around the plurality of electrically non-conductive elements by the plurality of nozzles.