Maximum plasticising performance
Long residence times and premium part quality
Plastics with new properties and increasingly complex performance profiles make ever more exacting demands on the plasticising systems of injection moulding machines. In order to keep abreast, manufacturers of plastification systems and their components are compelled to provide state of the art screw geometries, screw materials, screw and cylinder coating as well as screw tips and non-return valves
New challenge from additives and fillers. The development of completely new polymer materials is no longer part of contemporary raw material production, since the chemical modification and the introduction of new or improved additives is sufficient to yield parts with new property profiles. The introduction of flame retardants and stabilisers demands a particularly high chemical resistance of all plasticising components.
Mineral fillers with an abrasive effect on the equipment, oxidic pigments and reinforcing agents such as glass fibres are introduced to polymer materials in ever increasing con- centration. This highly-filled plasticised material is as demanding on the plasticising system’s wear resistance as rising temperatures or process pressure profiles.
High-performance shear and mixing sections for premium melt quality. More speciality chemicals – More screw variations
In addition to the classic three-section screw, the market demands a rising number of special screw geometries such as 25 D barrier screws with shear and mixing sections, special screws for PVC, LSR or thermoset processing. Maximum quality requirements for products such as crystal clear components, which are often produced with particularly shear-sensitive polymers, leave no tolerance for streaks, inho- mogeneity or excessive heat. These applications demand an extraordinarily high melt quality which is often only achieved by special screws.
A high-throughput rate is the first and foremost require- ment of high-speed applications. This demands both a spe- cial screw geometry and high screw torques. Hence, today’s packaging production relies almost exclusively on high- performance screws and electric metering motors. Moreover, colouring concepts such as direct colouring demand an effective homogenisation performance.