Extrusion International 2-2017

33 Extrusion International 2/2017 to replace an existing, less flexible line. “The greatest advan- tage of the new line is its enormous flexibility”, is how Kenn E. Byllemos expresses his satisfaction with the pipe extrusion line, which was installed about a year ago. This line is a 4-lay- er co-extrusion linewith four extruders and a co-extruder for color stripes, which also includes two FDC calibration sleeves and a complete set of FDC downstream equipment. In this way, diameters ranging from200 to 800mm can be handled by a single line, which is unique in the industry. The smaller of the automatic calibration sleeves handles diameters from 200 to 355 mm, the larger diameters from 400 to 630 mm. Diameter ranges from 710 to 800 mm can be handled with standard calibration sleeves. “In contrast to competitors’ products, our calibration sleeves are made of a cylindrical, rolledmetal sheet that comes close to a standard calibration in its design. The pipe dimension can be changed during production – seamlessly and fully au- tomatically. Both standard and customized sizes can be pro- duced with our calibration sleeves, not only in terms of ex- ternal diameters but also in terms of wall thicknesses, which may vary for example between 6.3 and 57.2 mm”, explains Brigitte Diekhaus, Project Leader at battenfeld-cincinnati. “The fully automatic dimension changewas a very important consideration for us, since we have more and more custom- ers demanding customized sizes, for example cap pipes. These must combine a very small wall thickness with a rela- tively large external diameter”, Byllemos adds. “In practice, changeover to different pipe dimensions takes us 20 min at most and changing to a different automatic range – e.g. from 200 – 355 mm to 400 – 630 mm can be effected within one shift. Another decisive advantage is that only very minor quantities of scrap are produced during dimension change”, are further reasons given by Byllemos for his decision to choose the FDC system frombattenfeld-cincinnati. “For a color change during production, we have scrap quan- tities of less than 500 kg”, Brigitte Diekhaus emphasizes. To achieve this, the lineoperateswithanadjustablemelt gapaf- ter to the pipe head, instead of a die-mandrel combination, which would have to be exchanged for a dimension change. For better results in color change, a radial distributor for the outer layer is integrated in the adjustable melt gap, so that the color change can be carried out quickly andwith relative- ly little material for purging the outer layer channel. Automatic dimension change and consequently the high flexibility of the line as a whole is finally also ensured by the FDC downstream components, which are also a unique feature in the industry. The vacuum tank operates with a pipe support system covering 180° of the pipe’s circumfer- ence and is steplessly adjustable over the entire dimensional rangewithoutmodifications. This also applies to the haul-off and cutting device, which can be adjusted automatically dur- ing dimension change as well. In close cooperationbetween theprocessor and themachine manufacturer, thehaul-off has beendesigned toprevent de- formation of customized pipes with small wall thicknesses. “The joint development work with battenfeld-cincinnati functioned perfectly, and we are very satisfied with the re- sult”, Kenn E. Byllemos praises the venture. To achieve the automatic changeover without any problems or human in- tervention, the battenfeld-cincinnati specialists have also extended the extruder control system in an optimal way, so that the changeover of all components can be effected at the push of a button. This type of fully automatic operation was also a decisive argument for Emtelle in favor of the line frombattenfeld-cincinnati. www.battenfeld-cincinnati.com, www.emtelle.com Close-up view of pipe head and calibration sleeve at Emtelle’s plant in Sønder Felding, Denmark during production With the FDC line, pipe dimensions and wall thicknesses can be changed during running production