Extrusion Asia Edition 2-2019

The MRS extruder itself has been improv- ed considerably over the last decade and at the K show the second generation de- sign will be on display. The enhanced drive design is more robust to handle even more demanding recycling environ- ments. Thanks to several changes in the MRS drum and screw design the already unmatched IV retention has been further improved, while continuing to forgo pre- drying. The MRS extruder permits the processing of PET without pre-drying by using a simple water ring vacuum system to process the material directly to high quality end products such as packaging sheet, strapping tape or filaments. This is achieved by means of its unique and pa- tented processing section. Based on a conventional single screw extruder, the Multi Rotation Section is a drum contain- ing eight satellite single screws, driven by a ring gear and pinion transmission. The “barrels” cut into the drum are approxi- mately 30 % open and provide optimum exposure of the melt. Thanks to this design, the devolatilizing performance is approx. 50 times greater than that of a conventional vented single screw extruder – and this at a vacuum of only 25 to 40 mbar. While other dryerless technologies are promoting at least par- tial pre-drying in the meantime, the MRS extruder can process R-PET with up to 1 % moisture content. By avoiding the need for a deep vacuum system and pre- drying, the MRS is an economically effi- cient alternative to conventional techno- logies. Further arguments in its favor be- sides energy savings are the simple and rugged design, small footprint, its ease of operation and low maintenance, pro- cessing flexibility and last but not least its excellent melt quality and homogeneity. A Letter of Non Objection (LNO) from the FDA, EFSA conformity and several lo- cal approvals in Latin America confirm the decontamination efficiency of this technology. One area this has been especially suc- cessful is in PET sheet extrusion. The line at the K will be delivered to a customer in Brazil after the show to process R-PET into a packaging sheet. In parallel, with Gneuss’ headquarters only about 200 km from the show, a complete PET sheet extrusion line with a Gneuss GPU will be running in Gneuss’ technical center open to visitors. Additionally, the previously exhibited po- lyreactor JUMP will be operating in Gneuss’ technical center for an online demonstration. The JUMP can lift the IV value of a PET melt up to 0,95 dl/g. The reactor is installed directly down- stream of a Gneuss Processing Unit and the polymer passes over several slow turning elements which create a polymer film, the surface of which is constantly renewed. The reactor vessel is kept und- er vacuum, through which volatile sub- stances are reliably removed. By regulat- ing the residence time in the reactor, the vacuum, the fill level and the speed of rotation of the agitating devices, the po- lycondensation reaction can be altered to achieve the required product proper- ties. The JUMP is a compact, quick and efficient alternative to conventional SSP (solid state) systems and enables direct reintroduction of the polymer into the production process without the need to remelt the PET. The days of analogue measurement va- lue transmission in polymer technology are numbered. With the requirements for flexibility, availability and safety of the machines and systems becoming more and more stringent, there is a need for new, digital solutions. IO-Link is a worldwide standardised tech- nology for digital linking of sensors and actuators. Communication takes place over a point-to-point connection and is thus not a field bus. IO-Link is manufac- turer-independent and is becoming more and more widespread in industrial auto- mation engineering. Most renowned controller manufacturers offer IO-Link masters, which are either directly fitted as an assembly in the controller or instal- led in the field and connected via a bus system. The traditional melt pressure sensor with an analogue output knows significantly more than just the process pressure. The signal preparation on its inside has been digitised long ago, and as a result, it is in a position to provide valuable informa- tion that simplifies maintenance, increas- es safety and improves availability. Pre- ventive maintenance and condition mo- nitoring can minimise downtimes and optimise process safety. The melt pres- sure sensor could make a substantial contribution in this regard, if it could di- vulge its knowledge. But unfortunately, its communications facilities are limited to one direction and one measurement value. The Gneuss IO-Link sensor offers the possibility to access all those informa- tion. Its proven sensor technology, in combination with intelligent, digital communication not only offers monitor- ing of the electronics temperature, but also records the operating hours in diffe- rent load ranges. Thus, the user can make out, during ongoing operation, when the electronics head is subject to high heat radiation due to its installation location, or the sensor is continuously working at the upper limit of its mea- surement range. In addition, Gneuss' Measurement Tech- nology division will present its complete line of pressure transducers and trans- mitters, temperature sensors and acces- sories. ➠ Gneuss Kunststofftechnik GmbH gneuss.com K 2019: Hall 9, Booth A38 9展馆, A38展位 数字化通讯的IO连接熔体压力传感器, Gneuss Gneuss IO-Link pressure transducer 38 预习 / Preview Extrusion Asia Edition 2/2019