Screw supporting device and twin-screw extruder with same

Abstract

The invention provides a screw supporting device and a twin-screw extruder with same. The screw supporting device comprises a screw supporting element and a shaft sleeve, wherein the screw supporting element and the shaft sleeve are combined for use, and are respectively mounted on same axial positions of two screw mandrels; by taking a center line of the screw supporting element as an axis, a virtual cylindrical surface tangential to screw flight of another screw which is provided with a shaft sleeve at the same axial position, and a screw supporting element part with a distance, greater than the radius of the virtual cylindrical surface, to the center line are constructed; an axial distance of adjacent screw elements at the two ends of the shaft sleeve which is combined with the screw supporting element for use is greater than zero; and a gap, in a radial direction, between the screw supporting element and the inner wall of a machine barrel is smaller than a gap between the screw flight of the screw and the inner wall of the machine barrel. According to the twin-screw extruder with the screw supporting device provided by the invention, two or more different positions of the screws are supported, so that abrasion between the screws and the machine barrel as well as between the screws is eliminated.

Description

technical field [0001] The invention relates to a screw support device, in particular to a screw support device for a twin-screw extruder, and a twin-screw extruder with the device. Background technique [0002] Twin-screw extruders are widely used in polymer processing such as molding, blending, modification, and reactive extrusion due to the variability and adaptability brought by its building block structure and excellent mixing performance. The twin-screw extruder mainly includes a transmission system, a feeding system, an extrusion system, a heating and cooling system, and a control system. The extrusion system is the core part of the twin-screw extruder, mainly including a screw and a barrel. The material is fed into the barrel by the feeding system, and the rotation of the screw in the barrel produces screw conveying and mixing effects on the material, so that the material undergoes extrusion processes such as solid conveying, melting, exhaust, mixing and melt conveyi...

AI Technical Summary

Problems solved by technology

If the wear occurs in the melting section, it will lead to a decrease in the melting ability, and cause uneven temperature and pressure fluctuations; if the wear occurs in the melt delivery section, it will reduce the melt delivery ability; between the flight of the screw and the inner wall of the barrel The increase of the gap will also reduce the heat transfer efficiency between the barrel and the material

At the same time, the environment of the two screws is not exactly the same, and the flexible deformation of the two screws will also be inconsistent, causing the screw elements on the two screws to contact each other, causing wear, cutting, and resulting in uneven material flow

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