Extrusion Asia Edition 1-2020

cept which makes sense, for the relatively small company with just 15 employees makes 60 to 70% of all sheet products re- quired for greenhouseshothouses worldwide. And the market leader continues to grow. This is why it increased its production capacity at the Danish facility fourfold with the installation of the high-speed line and established a subsidiary in Chicago/ USA, equipped with a thermoforming line to start with. “Espe- cially in North America, there is an enormous demand for our so-called ‘Danish trays’. The reason is the increasing cultivation of cannabis, which is not only grown for medical purposes, but due to its legalization in several federal states also more and more in demand for leisure applications”, explains Jacob Sören- sen, suggesting that he may further expand his overseas facility in the near future and install an extrusion line there, too. Until that time, the company will continue to transport its Danish trays to the United States to have them thermoformed locally. “This is the only way we can guarantee our high quality stand- ards to our customers.” High quality standards and … For the 3-layer sheet line from battenfeld-cincinnati installed in 2018, Staal og Plast first built an entirely new hall to house the line with a total length of 65 meters and also to provide enough space for the huge thermoforming machine and extra space for handling the largest boards, which measure 2,500 by 8,000 mm. In the new co-extrusion line, the high-speed extru- der 1-75 T6.1 is responsible as main extruder for the total ca- pacity of up to 3 t/h. It alone reaches an output of about 2 t/h for HIPS. High-speed extruders come with a very compact de- sign and reach their enormous output rates with high screw speeds. The melt’s residence time inside the extruder is long enough to achieve optimal homogenization, yet short enough to prevent mechanical or thermal damage and thus ensure op- timal melt attributes. In Denmark, the high-speed extruder pla- sticizes the material for the main layer, with in-house scrap re- sulting from changeovers and cuttingstamping being added to the virgin material. The material for the outer layers of the 3- layer composite is provided by two 1-75 T2.1 co-extruders. These, too, are high-speed extruders, each reaching outputs of up to 500 kg/h. “The outer layer, which comes into contact with the plant pots, is a distinctive feature of our trays. It is approved for food production as well as resistant to UV radiation and chemi- cals. We developed its formulation in cooperation with a Da- nish partner company”, the Managing Partner emphasizes. … knowledge of customers’ needs as success factors While the requirements for food safety and UV-resistance of the outer layer are a matter of course for greenhousehothouse trays, the need for resistance to chemicals is a specific conse- quence of working with ebb & flow trays. These trays, on which the plant pots stand, are flooded at regular intervals with water containing the fertilizers needed by the plants. After a specific period of time, the water and the additives it contains are drained and returned to the tank. Naturally, the irrigation medium is recycled to minimize water consump-tion. “To en- sure the correct dosage, the water is tested and replenished with fertilizers each time prior to flooding”, Jacob Sörensen re- ports. He also knows that mobile table systems are today’s trend for modern hothouses. In contrast to conventional rolling tables, which are still being used and can be pushed to and fro on a frame, the mobile tables can be pushed in every direction. This enormously facilitates handling for the operators. Staal og Plast offers the right trays for every type of greenhousehothou- se in the desired size and, above all, in high quality. For absolu- te flatness must be ensured as a prerequisite for even watering of every plant. Sörensen is confident: “Thanks to our know- how of more than three decades, our customers can rely on us”, and he regards this as the main reason for his market suc- cess. Set for further growth “Although the market for ebb & flow trays is booming and we have a good order situation”, says Jacob Sörensen, “at present we still have some free capacity on the new line.” He can there- fore well imagine that he could make polystyrene sheet as a service provider for other industries. Possible products are mo- no-layer, 2-layer or 3-layer boards in virtually any desired di- mensions with thicknesses ranging from 2 to 5 mm, and even in different colors if desired by customers. By the way, most of the ebb & flow trays are gray. The equipment in Ringe includes another sheet extrusion line for this purpose in addition to the new line, as well as a total of four thermoforming lines. The new line has replaced the second older line since 2018 and, apart from its high capacity, its main advantage is its low ener- gy consump-tion, about 40% below that of the old line. In ad- dition to the extruders already described, the new line includes a 3000-mm-wide flat sheet die, a roll stack with three main rolls and three post-cooling rolls, as well as a roller conveyor with thickness gauge and longitudinal cuttingtrim saws. At the end, there is a crosswisehorizontal cutting device for the up to 8m-long boards and a stackerstraddle carrier. “The line from battenfeld-cincinnati has even exceeded our technical require- ments. We are perfectly satisfied and well prepared for our cus- tomers’ future enquiries”, Jacob Sörensen states with pleasure, and concludes with a big word of praise: “Over re- cent years, battenfeld-cincinnati has been one of our most reli- able partners.” battenfeld-cincinnati Germany GmbH Grüner Weg 9, 32547 Bad Oeynhausen, Germany www.battenfeld-cincinnati.com 30 挤出技术-实例分析 Extrusion Asia Edition 1/2020