Four-motor physical foaming co-extrusion device

Abstract

The invention relates to a physical foaming extrusion device and particularly relates to a four-motor physical foaming co-extrusion device. The four-motor physical foaming co-extrusion device comprises four motors, extrusion machines driven by the four motors, an extrusion machine joint and three layers of co-extrusion machine heads, wherein a polyethylene foaming extrusion machine, a polyethylene transferring extrusion machine, an outer-layer extrusion machine and an inner-layer extrusion machine can form a three-layer structure including an inner layer, a foaming layer and an outer layer once by a layer-separated extrusion technology, the three layers are mixed to form a whole body, the extrusion is insulated and uniform, and the OD (Outer Diameter) and the concentricity of extruded wires are stable.

Description

technical field [0001] The invention relates to a physical foaming extrusion device, in particular to a four-machine co-extrusion physical foaming extrusion device. Background technique [0002] At present, the traditional physical foaming technology mostly adopts the layered extrusion mode of inner layer, foamed layer, and outer layer. Such layered extrusion will make the insulation thickness difficult to control, and will lead to uneven insulation thickness, so that the wire extrusion 0D, concentricity, The degree of foaming etc. is not stable. Due to the high foaming degree of thin-skinned physical foaming products, to improve the stability of the foaming degree, it is necessary to increase the length-to-diameter ratio of the screw (the ratio of the length L of the working part of the screw to the diameter Ds of the screw is called the length-to-diameter ratio). The maximum length-to-diameter ratio of the 20mm screw is only 40, and according to theoretical calculations,...

AI Technical Summary

Problems solved by technology

However, if the length-to-diameter ratio is too large, the power consumed by the screw will increase accordingly, and the processing and assembly of the screw and barrel will increase; the possibility of screw bending will also increase, which will cause scraping between the screw and the inner wall of the barrel. Grinding, reducing service life

In addition, for heat-sensitive plastics, an excessively large aspect ratio will cause thermal decomposition due to long residence time, which will affect the plasticization and extrusion quality of the plastic.

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