Christian Harste, CTO Dörken

Dörken has started to produce innovative technical building membranes on SML lamination lines

In the past few months, the German company, Dörken, has put two new production lines from SML into operation. Highly permeable roof and facade membranes are manufactured as part of the company’s product portfolio. In addition to innovative properties, a large number of the new composite films are making a statement due to their particularly resource-saving and efficient manufacturing processes. To a large extent, the products and production processes were developed in SML’s Technology Center - even before the lines were planned or installed at Dörken.


When it comes to membranes for the construction industry, Dörken is the European market leader. In autumn 2022, the company opened a new production site in Hagen-Vorhalle in North Rhine-Westphalia, where the two coextrusion coating and laminating lines from SML are now up and running. The tailor-made plants are setting new standards in terms of functionality, quality monitoring and the degree of automation involved.


Previous product development at SML’s Technology Center
"The remarkable thing about this project is that Dörken did not carry out substantial parts of the product development process at its own plants, but on an industrial scale FlexPack® line located in our Technology Center," Dirk Beckendorff, Area Sales Manager at SML, explains. The product development process at SML took several years: Among other things, it included basic trials with the SML DoubleCoat process, test series with the most important products of Dörken’s portfolio and several test runs for the development and sampling of new roofing membranes. Since it was possible to certify a number of products even before the lines were commissioned at Dörken, the over-all product development process was accelerated quite significantly. “It was important for us to benefit from the opportunity offered us by SML. In addition to confirming the known recipes and processes, we were able to use SML’s pilot plant for our innovations at a very early stage. In principle, we have actively integrated SML’s plant into our Stage Gate process,” Christian Harste, CTO at Dörken, clarifies. Immediately after the installation of the two lines, Dörken was able to start regular production.


New standards for products 
One of the two multi-purpose coating and laminating lines at Dörken is equipped with SML's patented DoubleCoat technology. This technology enables a combined adhesive and extrusion coating process for the production of ultra-thin and highly breathable laminates. It allows the manufacturing of a wide variety of technical composites for the construction industry, such as vapor barriers or waterproofing membranes. The second production line is a combined line with two integrated adhesive roll coaters for the manufacturing of highly breathable roofing and facade membranes in one production step.


The thickness of the TPU membranes can be considerably reduced, compared to conventional products available on the market. Thanks to the innovative system technology, significantly improved water vapor permeability values can be achieved, with, at the same time, excellent product properties with regard to longevity. “Our new underlay membranes are impressive with their proven durability and thus long-term protection. Extreme quality and long-term tests as well as special test procedures confirm their extraordinary resilience. With a high elasticity and integrated self-adhesive edges, this new generation of products is the perfect solution for a wide variety of applications. It enables a higher energy efficiency and a raised living comfort,” Dörken-CTO, Christian Harste, states.


Intuitive operation – integrated inspection systems 
A central element in both production lines is the SMILE control system developed by SML software application engineers. This enables the highly intuitive operation of the lines, tailored to the respective production process and the associated functionalities. "Integrated inspection systems and our data management tool, BitWise, ensure the comprehensive monitoring of the entire process chain at both plants. The production parameters of each product can be completely traced," SML product manager, Johannes Danter, points out. This is an enormous help to Dörken when complying with the strictest quality standards, especially regarding the long-term product guarantees the market demands.


Modernisation with a significant increase in efficiency 
The two production lines from SML allow a massive increase in efficiency because of their lower raw material consumption. Compared to the plant and process technology previously available, the production of the new generation of highly breathable roofing and facade membranes takes place in just a single production step. In addition, the lines operate at a comparatively high production speed of up to 120 m/min. Along with considerable time savings, the waste generated during production is reduced to a minimum.


The two new lines from SML replace several existing plants and give Dörken the opportunity to produce innovative membranes. They emphasize Dörken’s claim to manufacture as economically and resource-efficiently as possible – with greatly improved product properties achieved through further development work.


Redlham, 02.03.2023