Curtain coater for wood paneling
Curtain coater (curtain coating)
Curtain coater is a modern, high speed production process for applying smooth films of lacquer, paint, varnishes, adhesives to the flat surface. The curtain coater still work to finish the panel with the moderately curved or routed. Curtain coater is the machine for application materials on the flat line finishing system. The curtain coater can do process of application finishing materials with a very high speed with very high material efficiency as well as the other flat finishing line (see my article about the spreading rate of finishing material). This tool can generate surfaces with a layer of film that is more flat and smooth without roll marks like on a roller coater. The finish result is almost as perfect as the spray application.
The curtain coating is passing an object that need to be finishes through a continuous stream or falling of the coating material being applied. The finishing material is pumped and flowed so that it can form a curtain or fall of paint. The object that is coated are passed the curtain of paint so that the object is streamed and wet by the paint flowed. The excess of material that are not layered at the surface, are trapped below the head in a reservoir, re-pumped and reused with very little lose of solvent. For the catalyst materials, it is necessary to use the double-head to place for the catalyst and coatings separately.
Different with the roller coater that is more suitable for UV coating applications; this tool can be used for a variety of paint. No special materials needed for the formulation of the paint. Many types of coating such as: nitrocellulose, water based, polyurethane, and even polyester are quite successfully applied with this machine. The specification needed is the material finishing should be quite thin so it can be pumped and flowed to form a curtain of material.
After the painted object get out of this machine then it must be taken and raised to be put into a drying room or oven. In the production process usually there are lot of shelves or racks are prepared as a place to put objects that have been coated. The shelves are then taken to a drying room where usually equipped with a drying oven to speed the drying process. The use of manpower to pick up and lift the work piece is preferable instead of making a long series of machines to make the objects with a layer of paint is dry soon they out of the tool. Although a series of ovens can also be made for this tool but it is very rarely made. Because if there is an oven installed at the machine, then it required a very long line. The line and oven is designed will be depending on the type of finishing material are applied.
This machine is widely used for finishing applications on a flat-field, such as wood panels, particle board, wall panel, top table, etc. This tool can generate more surface smooth and flat, but usually can not produce a film that is too thick, because it limited by the viscosity of the material applied. The viscous material such as filler or the high solid UV coating is not proper to applied with this machine. Materials should be sufficiently dilute so that can be pumped and flowed to form a curtain of coating. Too thick material is also risk to creating some finishing problem such as bubble, pinhole, or orange peel.