Material extrusion structure and material extrusion method of double-crew extruder

Abstract

The invention discloses a material extrusion structure of a double-screw extruder, which comprises a first screw and a second screw that are driven by a motor, an extruder barrel main body, as well as a vacuum dehumidifying port and a raw material feed port that are formed in the extruder barrel main body, wherein the first screw and the second screw are arranged symmetrically; spiral grooves capable of conveying a material along the material feed port to the vacuum dehumidifying port are formed in the surfaces of the first screw and the second screw; the ends of the first screw and the second screw are connected with a distribution gear box capable of allowing the first screw and the second screw to rotate inwards with different directions in the extruder barrel main body; and the distribution gear box is connected with an output shaft of the motor. The invention further discloses a material extrusion method of the double-screw extruder. According to the material extrusion structure and the material extrusion method, no additional fund investment is required, only the rotation directions and left and right positions of the two screws in the double-screw extruder are changed simultaneously, and the rotation directions are changed from turning outwards with the different directions to turning inwards with the different directions, so that the service lives of the screws and an extruder barrel are prolonged effectively.

Description

technical field [0001] The invention relates to the technical field of twin-screw extruders, in particular to an extruding structure and a material extruding method of a twin-screw extruder. Background technique [0002] Twin-screw extruder has the advantages of large shear, high output, uniform plasticization, low energy consumption and direct extrusion with powder. Therefore, it has been rapidly popularized at home and abroad, especially in the field of PVC extrusion processing, more than 90% of which use counter-rotating twin-screw extruders. However, if figure 1 , figure 2 As shown, the two screws of the existing counter-rotating twin-screw extruder rotate outwards in different directions. During the rotation, the separation force of the material reacting to the screws under the barrel is upward, so the screws are constantly in the production process. The top of the inner surface of the barrel is ground in place. Since PVC is a heat-sensitive material, it will stay ...

AI Technical Summary

Problems solved by technology

Since PVC is a heat-sensitive material, it will stay and decompose on the inner surface of the worn barrel, causing black lines or impurities on the surface of the extruded product

As the degree of wear increases, this phenomenon will become more obvious until the screw and barrel are scrapped.

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