When Hindrichs-Auffermann was formed by the merger, in 1908, of Gebrüder Hindrichs of Barmen and Auffermann of Beyenberg, a lot of history was brought together. Hindrichs Brothers, as it would be in English, was established in 1824, while Auffermann started business in 1811.
The newly formed company specialized in the production of non-ferrous semi-finished products and parts.
In 1948, the company was licensed to produce coin blanks and its last involvement in that area was the stamping of coin blanks for the introduction of the euro nearly four years ago when Hindrichs- Auffermann was taken over by Sandvik of Sweden.
In the early ’60s, Hindrichs-Auffermann started production of press plates with smooth surfaces for the production of laminates. In 1966, the company was taken over by Vereinigte Deutsche Nickel Werke. The production of textured press plate surfaces started in the 1970s, while the production of endless press belts with smooth or textured surfaces came in the early ’90s. These are the businesses on which the company is almost exclusively focused today.
A major change for the company came in 2000 when it was again taken over, this time by Sandvik of Sweden, to become Hindrichs-Auffermann GmbH. Subtle legal changes then occurred in 2002 by which the company became a division of Sandvik GmbH in Düsseldorf.
Hindrichs-Auffermann is now the trading name covering the production and marketing of all endless press belts and press plates for decorative surfacing of panels.
As readers of WBPI’s sister magazine, Surfacing World, will be well aware, that market sector has been making rapid progress in recent years, meeting demands for ever more realistic textured surfaces, as well as the more traditional, smooth (mirror, satin and matt) finishes. And it is the press plates and endless press belts which impart that texture to the decors.
Hindrichs-Auffermann puts its range of textures into seven categories: ‘Smooth’, ‘Alu’, ‘Perl’, ‘Stipple’, ‘Wood’, ‘Stone’ and ‘Grafic’.
“In Wood, for a more natural effect, we can reproduce the saw marks as well as all the different details and characteristics of the grain,said Stephan Gierke, manager of process control.
“It is difficult to reproduce the true depth of structures like stone but the demand is for increasing depth – 70 to 100 microns is the average but we are working towards 200 to 300 microns and this we have recently achieved in press plates. There is not so much demand for deep embossing in press belts, but we expect it to increase and this is also under development.”
The required properties of laminates are attractive texture, natural and appropriate gloss level, realistic feel, resistance to dirt build-up and ease of cleaning, and the ability to impart grip to the surface in some circumstances, explained Mr Gierke.
“These are all the responsibility of Hindrichs-Auffermann, working together with its customers.”
Meanwhile, the required properties of the press plates and endless press belts begin with the correct steel grade. Hindrichs-Auffermann uses one grade for press plates and two grades for the manufacture of endless press belts.
The company also has a new grade of steel coming to the market soon for endless press belts, specifically related to the heat transfer properties, to enable higher press speeds.
Steel purity, hardness, flatness and thickness/ thickness tolerances are also important considerations for these press tools.
Production of press plates and endless press belts involves four main stages. The first is the printing of the desired pattern on the metal surface. This is followed by chemical etching in Hindrichs-Auffermann’s case (some use mechanical etching), polishing and hard chrome plating. The required system for mounting in the customer’s press is the final stage of production.
Quality control in this business is absolutely vital as the slightest imperfection in the plate or belt will soon become obvious in the finished, pressed decor.
At Hindrichs-Auffermann, a careful visual check is followed by mechanical tests, gloss measurement, roughness tests, depth control and an assessment of the overall feel of the surface. The more subjective visual and ‘feel’ tests rely heavily on experienced personnel, of course.
As can be imagined, there are special requirements for endless press belts as the welding seams have to be totally invisible and must resist cracking in the severe bending and heating/cooling cycles to which they are subjected, while the chrome plating must also remain totally intact.
Special skill
Textured endless press belts provide an even more severe test of the company’s skills. “The material properties in the seam are different to the rest of the belt and this invisibility after etching is not easy to achieve,said Mr Gierke.
However, it should perhaps be borne in mind that Hindrichs-Auffermann has been producing press plates for around 40 years and endless press belts for 10 to 15 years now, so they certainly should know how to do it.
The company also offers a refurbishment service for both press plates and endless press belts and re-texturing for plates.
The gloss level decreases with use and ‘window framing’ can also develop. This arises especially in the production of flooring panels and is caused by the grinding and polishing effect between the surface of the melamine faced board and the press plate. As the press opens, the centre of the board moves away a fraction of a second earlier than the edges. At the moment the press plate comes completely away from the panel, there is a slight movement during which the aluminium oxides attack the press plate surface, giving a grinding effect. This part of the plate thus shows a higher gloss level than the remaining plate surface.
In order to restore a uniform gloss to the entire press plate, it must then be dechromed, re-polished and the chrome plating re-applied.
Obviously, if a foreign body becomes trapped in the press, more major repairs may be required.
The continuous belt presses often used in the production of laminate flooring, with its abrasive overlay, tend to need more frequent refurbishment of the stainless steel belts.
Of course China is seen by everybody in the panel industry as a growing market and Hindrichs-Auffermann is already there, with a refurbishment plant which it started up earlier this year.
Chinese personnel have been trained at the company’s factory in Germany and some German technicians have also gone out to China. The required specialist machines have been shipped to China from Germany and Sandviken in Sweden, headquarters of parent company and steel producer, Sandvik.
The talk of the decorative surfaces sector today is not just of embossed plates – that is well-established now – but of ‘embossedin- register’ (EIR) textures. This is where the texture is specifically aligned with the printed pattern of the decor to give a realistic see-and-feel dimension to the panel surface.
“We are in touch with several customers and are making some very individual textures with them,affirmed Mr Gierke. “We are also running some research and development projects in-house to further develop the production of EIR plates.”
In fact, Hindrichs-Auffermann refers to these as synchronous-porous plates and belts and has a range of them due on the market next year, in woodgrain, stone and ceramic finishes.
Global product manager Hans Peter Mischok joined our discussions to comment on the global nature of this business.
“We are supplying all the major panel manufacturing groups with both plates and belts,he said. “ The top trend in Europe and North America at the moment is for deep textured woodgrains – the rustic-type effects – which we deliver in both plates and belts.
“The Asian market is also increasing for us – particularly in China – while the last two years have been very slow in Europe. But we are beginning to see signs of improvement here too.
“For the last two years, it has mainly been refurbishment and re-texturing of plates and belts, but in recent months we have seen signs of more orders for new plates. Also, the press makers Siempelkamp, Dieffenbacher,Wemhöner, Bürkle and Hymmen are all reporting increased sales, which is a good sign for us as well.”
