COATINQ Castrop-Rauxel A new infrared booth negates the need for one stoving step for prime coats
Greater capacity for customers while retaining the high coating quality that customers appreciate from COATINQ Castrop-Rauxel GmbH. The powder coating plant that was recently commissioned was supplemented in April 2021 through the addition of an infrared stoving oven. In extensive test runs, together with the coating and plant manufacturers, the optimal setup for diverse steel and aluminum components was identified – this saves one entire stoving step.
Powder coatings in the two-coat system for steel and aluminum components usually require patience – even in the highly industrialized serial coating. In almost all cases, the components need to make the journey through the stoving oven twice so that both the prime coat and the top coat perfectly meet the demands of corrosion protection and aesthetics.
The recently commissioned infrared stoving oven gives COATINQ Castrop-Rauxel GmbH an exceptional capacity boost while retaining optimal coating quality: with this process optimization, the convection oven stoving process for the prime coat is skipped, thereby saving another 800 meter long journey through the coating course and the several hours, which that usually takes.
At the center of the process optimization is the infrared module (left), which spares the primed parts the time- and…
Fine-tuning of the new COATINQ plant in Castrop-Rauxel: the primer was applied manually for the test runs.
One line for both prime coats and top coats
COATINQ is a brand from the largest European batch galvanizing service provider ZINQ. COATINQ’s key expertise includes innovative and tailored coatings solutions of all kinds for materials such as black steel, aluminum, cast iron and continuously-galvanized surfaces. The company group runs the duplex system of one non-continuous batch galvanization process as the primer and a subsequent powder coating under the product brand colorZINQ. Significant funds have recently been invested into powder coatings at the location in Castrop-Rauxel: initially in a modern powder coating booth from Gema Switzerland GmbH, an internationally-operating provider in the field of powder coating systems.
The booth is fitted with 20 automatic coating guns, two hand guns and 22 application pumps, among other things. These pumps ensure powder output is constant and reproducible. They distribute powder coatings optimally with limited overspray, so that material losses can be significantly reduced. “With the investment in the new powder coating booth, we have increased our capacity and made our production much more flexible, so that we can change colors very quickly”, stated Michael Spaan, Plant Manager at COATINQ Castrop-Rauxel. However, for the time-consuming coating process that consists of a prime coat and a top coat, the team in Castrop-Rauxel felt that even more optimization potential could be tapped. The means to do so was found in the form of a infrared module from Heraeus Noblelight that can quickly be elevated and integrated into the coating line. In this infrared gelification zone, the previously applied epoxy prime coats are then sufficiently cured. Afterwards, the powder coating top coat is applied. Both coatings are then stoved together in just one passage through the oven. This saves time, is energy efficient and leads to a further increase to capacity, which customers of the company notice in terms of greater flexibility. To achieve an optimal, even better coating quality, COATINQ determined the best process settings together with its partners, in comprehensive tests and for diverse substrates.
The optimal setup depends on the material
There are many variables that can be adjusted that determine the degree of corrosion protection and the impressive appearance of the coated steel or aluminum components: two such parameters are the temperature and speed of water drying that occurs after pretreatment of the parts hanging on suspended brackets. Further affecting factors are determined by setting the power of the infrared module, the duration and temperature of stoving in the oven, the roller speed and of, course, the coating material itself, that is used for priming and the top coat. At its new plant, COATINQ uses products from Brillux Industrial Coatings. In projects like these, the paint and coatings manufacturer with its headquarters in Unna, Germany, always contributes with technical consulting on site and R&D expertise in order to determine the best coating for the respective specifications. In comprehensive tests, the setup in Castrop-Rauxel was finely adjusted – through the entire range of materials for material thicknesses from one to five millimeters.
The most important results: the optimal water drying temperature of 193°C proved to be constant for all materials in order to avoid bubble formation for the coating. Even the stoving oven temperature of 185°C remained constantly high throughout all tests. All other parameters depended on the material. While for two millimeter-thick aluminum elements or standard materials from metalwork such as metal fence panels, 40 percent infrared power was enough for curing the prime coat and optimally prepare the top coat, and 30 to 40 minutes of stoving led to the ideal results, for thicker materials, higher values were required. Steel components with 15 millimeters of diameter needed for example 100 percent infrared power and a duration of 50 to 60 minutes in the stoving oven.
Brillux Corro-Protect EP 5816 was chosen for the prime coat. The powder coating based on epoxy also clearly demonstrated in the tests which settings are optimal in the infrared booth: A glossy prime coat after passing through the infrared booth ensures that the top coat also flows very well and remains free of surface defects. The top coat, which COATINQ utilizes with the special color-stable Brillux Polyester Powder PE 5998 in the new plant allows exactly these characteristics: anti-corrosion and very good edge and node coverage. Subsequent assessment methods, such as layer thickness measurement and salt spray testing, demonstrated that the high COATINQ coating standards of protection and design are met and exceeded through the new application process.
In a network for further innovations
The company constantly pursues improvements in surface finishing such as these, which COATINQ offers its customers from the fields of construction, vehicle and machinery manufacturing as well as industrial machinery. “Here we work beyond our own network, such as in the new plant in Castrop-Rauxel, with partners that share our high demands of service, reliability, development expertise and sustainability”, highlighted Michael Spaan. And at the two other German coating sites in Bruchsal and Leipzig as well as at found other in Benelux, France and Poland, innovations arise that constantly expand and improve the variety of application techniques and processes of the company ZINQ. The duplex system colorZINQ is one example of this: batch galvanization plus a subsequent colored powder coating in countless possible RAL color shades – that’s how individual aesthetics are combined with especially effective corrosion protection.
Involved parties
Plant operator:
COATINQ Castrop-Rauxel GmbH
www.coatinq.zinq.com/home-coatinq
Plant manufacturer:
Gema Switzerland GmbH (Pulverbeschichtungsanlage)
www.gemapowdercoating.com
Heraeus Noblelight GmbH (Infrarotofen)
www.heraeus.com
Powder coatings:
Brillux GmbH & Co. KG Industrielack
