Extrusion International 5-2025

57 Extrusion International 5/2025 MEASUREMENT TECHNOLOGY, BLOWN FILM Türk explains: “The lower the tem- perature of the PE melt, the more viscous it is, and the less sagging occurs. The less sagging, the better the pipe quality and wall thickness distribution.” In the extruder itself, a solEX NG, the combination of a spiral grooved barrel and match- ing screw and grooved bushing ge- ometry ensures high speci c out - put rates at low screw speeds and therefore low melt temperatures. Compared to previous extruders, the melt temperature is around 10 °C lower. A further temperature re- duction of around 10 °C is achieved with the OptiMelt active melt cool- ing system. This powerful melt cooler is installed between the ex- truder and the mold. Furthermore, the two-stage VSI pipe head, a combination of spiral mandrel dis- tributor and screen basket patent- ed by battenfeld-cincinnati, guar- antees uniform melt distribution in the pipe and thus ensures uniform cooling and extremely narrow wall thickness distributions. Thanks to the sophisticated concepts of all individual components, the high- quality large-diameter pipes can be produced in an energy-ef cient manner. All downstream units, which are designed for a wide range of pipe not dimensions up to 2.7 m, can manage with low energy and water consumption, contribute to this. In the vacuum and cooling tanks, the pipe can also be cooled individually in sections around the circumference. This option can also further improve the wall thickness distribution and minimize ovality. battenfeld-cincinnati www.battenfeld-cincinnati.com Plastics Pipes & Products Co. (PPP) www.ppp-eg.com What Do Film Thickness Gauges Have In Common With Pasta Sauces? When it comes to picking the correct sensor type used to measure blown lm thickness pro les, a comparison can be made to selecting the perfect sauce for a particular type of pasta. In both cases, having only one or two choices signi cantly reduces the possible range of success. S ince the mid-1980s, Kündig Control Systems (KCS), a specialist division of Hch. Kündig & Cie. AG (HKC), has been supplying width and thickness measuring devices to the blown lm industry. KCS provides high speed on - line thickness measurements from the tube portion of the lm bubble. This is the cornerstone of achieving op - timum thickness tolerances - also contributing to saving valuable raw materials and reducing waste. As a result, these devices are not only an economic investment, but also an ecological one. The performance requirements for these thickness measuring devices have risen steadily over the last 40 years. In particular, production rates are much higher in modern blown lm lines than it used to be. This leads to more turbulent lm bubbles and hotter lm temper - atures at the measuring point. Capacitive thickness measurement remains the pre- ferred method for lms based on polyole ns and those with low proportions of polyamide, EVOH, and other materials with similar properties. This is due to its mea-