Ledro Keukens NV - MDF Powder Coating Oven Case Study

MDF Powder Coating Oven Case Study

Excerpted with permission from ITW Gema AG publication

Ledro Keukens NV: State-of-the-art powder coating technology in Belgium
Under the direction of Paul Peters, Ledro Keukens NV based in Houthalen-Helchteren, Belgium has become one of the most renowned kitchen and bathroom manufacturers in Europe. Created in 2003, the Ledro Powder Coatings division is equipped with todays most advanced production line for MDF panel powder coating in Europe.

MDF powder coating technologyAt Ledro Keukens NV, the increasing demand for MDF products from the furniture industry coupled with a progressive corporate philosophy recently led to the decision to invest, as a pioneer in the sector, in the future-oriented powder coating technology for MDF items.

Why powder coating has been chosen? Powder coating is the best surface application for modern and environment-friendly MDF coating. In the Belgian premises, 90% of the MDF panels are coated with PVC foils. This process is well-established, but it does generate relatively high handling costs and waste rates.

Paul Peters, General Manager of Ledro, is convinced of the benefits of powder coating:

A further advantage: the free choice of design for all MDF products! With laminates or foils, the shaping of the MDF parts is very limited, that is to say it is reduced to rectangular products. Powder coating allows for all kind of shapes, a fact that certainly brings joy to the furniture designers hearts worldwide.

MDF and Metal coatings the major differences
Powder coating MDF partsEdwin Kuipers, Poduction Manager at Ledro Keukens, is well positioned to give further information: MDF is a continuously changing material, it literally lives! For example, MDF panels react very quickly to variations in temperature. Also variations in quality within the MDF panels of one production lot are immediately detected on grounds of faulty coating results. Unlike metal parts, MDF does not allow paint-stripping and subsequent recoating, rejects are rejects! The entire plant configuration is structured in a completely different way than it is for metal coating. The cooperation between MDF panel manufacturer, powder producer, oven builder and application manufacturer is very important. The coating process has to be seen as a whole, each component is only as strong as the weakest link of the chain.

The MDF panel: The panel should have a correct humidity level, short fibers and have a high Internal Bond Strength. In addition, it is important, that the MDF panels feature a certain tensile strength.

The powder: Ledro Keukens uses Drylac Wood from Tiger Coatings, which is based on the low bake principle, that is to say cured at low temperatures. The powder was especially designed for the use on MDF material and is continuously being developed in line with the latest technological advances.

The oven: The gas catalytic oven of the US-based company Heraeus Vulcan is the heart of the entire installation. This is a 3 oven, 2 coat system with the first coat being a primer powder and the final, a color powder. Thanks to precisely controlled ceramic catalysts and properties of the Infrared that is emmited, the MDF panels are preheated and subsequently powder coated and then cured. Compared to convection ovens and UV systems, gas catalyst technology is not only far better to control and adjust, but also more cost-effective while not subjecting the board to prolonged exposure to hot air in a convection oven that destroys the mechanical properties and dries the wood to dangerous levels.

MDF Powder Coating Case StudyThe application: With regard to the powder coating installation, it is very important that all electrostatic parameters can be exactly controlled to compensate the slightest changes in the characteristics of the MDF panels. Ideally suited here is the ITW Gema powder gun OptiGun coupled with the OptiTronic control unit. The plastic booth with optimized airflow guarantees quick color changes. In case of manual pre-coating tasks, a separate manual booth is added.

Peters says, "In questions of MDF panel powder coating, we still have to learn a lot. In the last years, however, decisive advances have been achieved, in particular in the field of coating powders and MDF material". Ledro does not try to keep its gained know-how secret. On the contrary, the kitchen manufacturer makes its installation accessible to interested companies. Why this rather unconventional attitude? We would like to share our know-how so that the entire industry can profit from our important progress achieved over the last years. Only in this way, can we find a way out of the standstill and then MDF powder coating will advance, says Paul Peters. Hats off for such an attitude!

Excerpted with permission from ITW Gema AG publication