Extrusion International 6-2024

29 Extrusion International 6/2024 grade L5220, which contains a lowoil content, offers self- lubricating properties. Lubmer TM-80B is aweather-resis- tant grade that was specially developed for glass running channels (GRC) in motor vehicles. These granules are the only UHMW-PE products in the world that are suitable for traditional thermoplastic processing methods. They allow the use of hot runner technology and tunnel sprue systems for injection moulding technical parts, and they are also suitable for the extrusion of sheets, profiles and hoses. In both cases, their opaque, light inherent colour facilitates colouring with masterbatches. Unlike the granules suitable for direct processing, Lubmer LY1040 is a masterbatch based on the standard grades that is compatible with most engineering plas- tics and can replace PTFE as an additive. As a PFAS-free engineering plastic modifier, it exhibits better sliding properties than PTFE or molybdenum disulphide even at low addition levels of 3 to 5 %. It can also significantly improve the wear resistance of PA6 and many other ma- terials without affecting the substrate properties. Typi- cal applications include bearings and gear parts for elec- trical equipment and automotive interior parts as well as mechanical components for lifts and escalators. Mitsui Chemical has developed the PA Lubmer alloys LS4140 and LS4120 for applications that require increased mechanical strength. The PA masterbatch LY4100, which can be added during extrusion or injection moulding without compounding, rounds off the portfolio. At their end of life, all Lubmer product types can be returned to the PE recycling loop thanks to their ther- moplastic processability. Another plus in terms of sus- tainability is the fact that injection moulding produces little to no waste, unlike the machining of conventional UHMW-PE products. And due to its density, which is half that of PTFE, LUBMER has proven to be advantageous for use in lightweight components with increased durability. Together with customers, Dreyplas and Mitsui Chemi- cals Europe develop solutions for the substitution of PTFE as well as special grades with application-specific properties that go beyond those of the standard grades available. MITSUI CHEMICALS EUROPE GmbH https://eu.mitsubishi-chemical.com DREYPLAS GmbH www.dreyplas.com Even at a low dosage of 5 %, UHMW-PE Lubmer reduces the friction coefficient of engineering plastics much more efficiently than PTFE (© Mitsui Chemical) ReliablyFeedingandShreddingEdge Strips from Trimmed Film Webs A t Fakuma, Hellweg Maschinenbau showcased its solution for reliably, continuously and uninter- ruptedly shredding profiled edge strips. The more pro - nounced the profiling, the more often granulators with a conventional feed and chop configuration fail to per - form because the strips are then difficult to grip and convey. Such problems are a thing of the past for opera- tors of Hellweg Maschinenbau’s completely redesigned LSZ 150/100 edge strip shredder that feeds and shreds the strips in a single step with no blade, no screen, no infeed device, and no resharpening of the toothed roll- ers. Years of low-maintenance and trouble-free opera- tion combined with low cleaning requirements mean the shredder is also economic to run. The key elements behind these advantages are the four hardened toothed rollers machined from solid tool steel billet. Mounted in pairs in a steel housing, these provide a working width of 150 mm. Thanks to not re- quiring a separately driven, failure-prone infeed device, they forcefully guide the edge strips away from the sheet material during production while keeping them under tension, regardless of strip geometry. An infinite - ly variable roller speed enables feed speeds of between 0.8 m/min and 6 m/min, so allowing granulation to be perfectly adapted to the production process. Due to their optimized arrangement and shape, the rollers’ teeth shred the edge strips without interruption into a readily flowable, uniform regrind with an edge length of around 5 mm to 10 mm. This can then be add- ed directly to virgin material. As a result, there is also no need for a separate screen as required by other systems for separating over- or undersized regrind. Profiled edge strips are typical in the manufacture of sheet webs that, following extrusion, are thermoformed into products such as dimpled sheet or green roof mat- ting. This results in projections on both edges that not only interfere with feed but also delay feed opera- tions during intermediate thermoforming operations.