The extruder development of KUHNE GmbH goes far back to the year 1949. Out of the disorders from the second world war, resulted the first approach to design and build a machine, able to melt plastic. An old drilling machine was used for the prototype of the extruder by putting a cylinder on top instead of a standard tool. The extruder screw was driven by the motor of the tool, the heating was – already then – realized by heating bands. Resulting from this were the first, pure extruders, mainly for profiles and tubes out of PVC, but from 1952 onwards also the first lines for sheet and blown film.
In 1959, Werner Battenfeld took over the extrusion facilities in Siegburg and integrated them into his worldwide operating company. The brand “Battenfeld” was worldwide known and famous for injection machines, extruders and textile machines.
The first General Manager of the Battenfeld extrusion site was Walter Kuhne, who continued to develop the extrusion technology for Battenfeld after having completed his universal studies in engineering. By end of the sixties, the fast growth of the group led to serious financial problems, giving Walter Kuhne the chance to use a Management Buy Out in order to get possession of the extrusion facilities and to rename the company into KUHNE GmbH.
In the following years, KUHNE GmbH concentrated on the production of blown-film and flat-film; as well as sheet-lines. One of the first blown-film lines was already built in the early fifties, so that approximately twenty blown film lines per year were delivered worldwide – all with the name and brand of Battenfeld, but designed and built by the future KUHNE staff.
Already in the year 1956, sheet lines for the production of PC had been delivered – also first tests with PE-sheets were realized. In the thermoforming business, still very young at that time, first machines have been sold in the sixties for the production of PS and PVC.
In the seventies, KUHNE GmbH developed for example the first coextrusion-line for milk and stripes film, where up to four extruder produce different colours side by side into one blown film.
An additional milestone for KUHNE was reached by placing HDPE extrusion lines in the market in the eighties. More than 500 of these lines – most of them built on rotating platforms – were sold. In the same period, a significant amount of PS and PP Inline-machines were sold to dairies and their suppliers. In the sheet sector, the first huge lines with working widths up to four meter and thicknesses up to 30mm were developed, sold and delivered.
The nineties for KUHNE were dominated by coextrusion blown film lines – becoming more and more big and powerful – as well as the ongoing development regarding multi-layer feedblock systems for flat film and sheet lines. Outputs were continuously raised and layer thicknesses more and more reduced; in the same time tolerances minimized.
In the first decade of the new millenium, the number of delivered blown film lines for five and seven layer has been rising. In Flat Film extrusion, KUHNE presented the High Speed concept – a system that almost doubled outputs by keeping the extruder size at the same time. Another highlight in sheet extrusion have been numerous lines for the production of tanks for the automotive industry (the so called “twin sheet principle”). The needed tank sheets are extruded, welded and used in cars of worldwide known producers.
Since 2010 until today, KUHNE has installed more than 20 flat film lines for the production of coffee capsules. The heart of these machines, which are producing in six different countries, is the KUHNE patented and own developped lamella feedblock. It allows a perfect layer distribution with a extraordinary barrier effect and in the same time lowest tolerances. Smart Sheet has been improving that feedblock system continuously.
In the field of high speed extrusion, more than 500 extruders have been delivered since 2008. Besides the standard types 60 and 72mm, KUHNE has also introduced the 45 and 90mm extruder as a high speed version in the meantime. They reduce for our customers space, energy costs and noise – thanks to their water cooling – with high screw speeds and output rates.
As for KUHNE sheet lines: The possibility to produce 50mm thick sheet has become a standard for some time now. Also the auxiliary equipment of these machines such as automated sawing, milling and stacking are part of our core competences.
But KUHNE Smart Sheets also stays to be the first contact when it comes to customized machine engineering. Every year we are building and delivering 2 – 3 machines for the production of geomembrane films. With net widths up to 8500mm, output rates up to 4 tons per hour and thickness tolerances below 1%, we are winning customers worldwide. Even the huge die for these lines is KUHNE-made.
In the special segment of extrusion coating, KUHNE has installed the line with the biggest with worldwide. This machine produces reinforced net films. A huge advantage is to bring together net and film inline in one single process.
From 1949 until today, thousands of KUHNE lines and machines are running all over the world – still rising constantly. Innovations – such as the “Triple Bubble Principle” for the production of biaxial stretched film with excellent barrier properties and up to thirteen layers – as well as the “Water Quench Principle” with its high performance water cooling ring, continue to change the world of packaging significantly.
This is how the story of success reveals and continues, that started after the end of world war 2 with the manufacturing of the first extruder…