In Korea, Dongjin is known as the largest producer of thermoformed packaging, most of which is exported, but some also sold on the domestic market. In 2015 the export rate was already 30%, with the main markets being the USA and Japan. By expand-ing its plant, Dongjin wants to extend its product portfolio and intensify its market presence.
The plastics processor and battenfeld-cincinnati have already been partners for more than 20 years. For sheet production, Dongjin uses seven lines from battenfeld-cincinnati: two 7-layer lines and five simple co-extrusion lines - two of which are for PS, two for PP or PS and one for PET. The new 3-layer line for PS and PP sheet with the Multi-Touch roll stack will be added in the near future. "With the first Multi-Touch high-performance line we can produce 40% of the sheet needed and at lower energy cost", says President & CEO Song Seok Hwan. Thanks to the new high-performance extrusion line, the processer now needs to buy significantly less sheet from external suppliers. This is a great advantage, particularly as the investment cost of the line is paid off by the energy savings. The complete line needs about 15-20% less energy than a conventional sheet extrusion line.
The main driver of the enormous energy savings is the high-speed extruder, the second key component of the line next to the Multi-Touch roll stack. With a screw diameter of 75 mm and a 40 D processing unit, the extruder reaches outputs of up to 2,000 kg/h, depending on the material processed. Thanks to the optimized de-sign of screw and barrel, the extruder ensures excellent melt quality even at high screw speeds of up to 1,200 rev/min and thus lays the foundation for high product quality.
Quality combined with high transparency, flatness and even sheet thicknesses are the parameters sought by today's packaging industry. The Multi-Touch roll stack has been designed particularly with this in mind. In contrast to conventional 3-roll roll stacks, the new roll stack works with a large number of roll gaps which ensure reliable cooling and calibration of the upper and lower side of the sheet. In the Multi-Touch roll stack, the sheet first passes through a pre-calibration unit made up of two large rolls. Then the sheet reaches the re-calibration, which is equipped with either three, five or seven small rolls. Thanks to constant contact with the rolls, the sheet shows little orientation and a particularly even thickness profile with an accuracy of ±1%. This enhances the efficiency of the line, as significant material savings can be achieved compared to conventional sheet extrusion lines.
With its Multi-Touch line concept, battenfeld-cincinnati perfectly meets the needs of the packaging industry for high-quality sheet produced at high outputs with low energy consumption.