Today, the Multi Rotation System extruder from Gneuss is operating in a number of different PET applications worldwide, including sheet, fiber and pelletizing applications.
The MRS offers new possibilities to PET converters because it permits the processing of PET without pre-drying or crystallizing. Byproviding a very large surface area and using a simple water ring vacuum system it is possible to process the materialdirectly into a high quality product. This is achieved with a unique and patented processing section. Based on a conventional single screw extruder, the Multi Rotation Section (MRS) is a drum containing eight satellite single screws, driven by a ring gear and pinion transmission. The “barrels” cut into the drum are approximately 30 % open and provide optimum exposure of the melt.
Thanks to this design, the devolatilizing performance is fifty times greater than that of a conventional single screw extruder – and this at a vacuum of only 25 to 40 mbar. By avoiding the need for a high vacuum system and pre-drying, the MRS is an extremely economically efficient alternative to conventional technologies. Further arguments in its favour are the simple and rugged design, small footprint and flexibility.
In addition to the excellent devolatilizing performance, the MRS also offers excellent decontamination performance. The US American Food and Drug Administration (FDA) issued a total of 4 LNOs (letter of non objection) for the MRS extruder for reprocessing material for the food industry.The MRS extruder not only efficiently extracts water but also decontaminates the material so that up to 100 % PET bottle flakes can be processed to food containers. This is achieved without the need for any treatment of the material before or after it is processed on the extruder (no restrictions on the washing process, no drying, no crystallizing etc.).
Gneuss’ Online Viscometer VIS has been equipped with an improved and more robust drive with an encoderless speed control. The viscometer offers precise measurements of the melt viscosity and thanks to its very compact design can be added to almost any extrusion line.