Same-direction self-cleaned twin-screw extruder with baffle plates and processing method thereof

Abstract

The invention discloses a same-direction self-cleaned twin-screw extruder with baffle plates and a processing method thereof. A screw mechanism of the same-direction self-cleaned twin-screw extruder comprises a first screw rod and a second screw rod, wherein the first screw rod is in a single thread structure, and the second screw rod is in a double thread structure; the baffle plates are arranged in the screw grooves of the first screw rod, and the height of each baffle plate is less than the depth of each screw groove of the fist screw rod; 8-shaped hyperbolic flow disturbance can be formed at the baffle plates in the screw grooves of the first screw rod; and the first screw rod and the second screw rod rotate at the same speed, are meshed with each other at all times and are self-cleaned simultaneously. According to the processing method, the screw grooves are triggered under the action of 8-shaped hyperbolic flow disturbance formed due to the arrangement of the baffle plates to mix materials chaotically all the way, two flowing ways formed by the two screw rods fulfill the topological chaotic mixing function of dividing materials into two parts, mixing the two parts of materials and dividing the mixture into two parts, and the first screw rod and the second screw rod fulfill the functions of compressing, expanding, recompressing and reexpanding periodically. Under the joint action of three reinforced mixing mechanisms, the materials can be molten and mixed efficiently.

Description

technical field [0001] The invention relates to the technical field of twin-screw extruders, in particular to a co-rotating self-cleaning twin-screw extruder with baffles and a processing method thereof. Background technique [0002] The co-rotating twin-screw extruder with self-cleaning function is a widely used mixing processing equipment at present. This type of equipment mainly includes a barrel and twin-screws installed in parallel in the inner cavity of the barrel. In order to generate high shear, the screw with multi-thread structure is often used, which leads to different topological routes of material flow. When the processed material enters the inner cavity of the barrel from the feed port, the material will enter different topological flow channels. For example, the double-head thread will divide the flow channel in the barrel into three disconnected flow channels. The materials will not mix with each other during the forward conveying process. The unevenness of ...

AI Technical Summary

Problems solved by technology

In order to generate high shear, the screw with multi-thread structure is often used, which leads to different topological routes of material flow. When the processed material enters the inner cavity of the barrel from the feed port, the material will enter different topological flow channels. For example, the double-head thread will divide the flow channel in the barrel into three disconnected flow channels. The materials will not mix with each other during the forward conveying process. The unevenness of the feed composition may lead to the material components entering different flow channels. Inhomogeneity, this unevenness will not be improved by mixing with each other during the forward process of materials, so it is often easy to cause unstable product quality

[0003] Only in the area where the kneading block is installed can it be mixed with each other, but the kneading block will cause many problems such as high shear, material accumulation, dead space and reduced self-cleaning performance

On the other hand, due to the geometric meshing relationship, the use of multi-start threads will also lead to shallower grooves and lower output

The traditional co-rotating twin-screw extruder only provides disturbance in the meshing area to improve the mixing quality, and lacks a chaotic mixing trigger mechanism away from the meshing area. Moreover, the volume of the material in the left and right screw grooves is the same, and the mechanism of the tensile force field cannot be introduced. The main part of the screw channel volume lacks a structure that can effectively improve the mixing, so that the distribution mixing effect cannot be further improved, and the lack of tensile force field effect leads to unsatisfactory dispersion mixing

In addition, most of the processing process of the twin-screw extruder is in a non-full state, and there is almost no changing flow path, which leads to a great reduction in the plasticizing and mixing effect of the material. In order to improve the mixing effect and increase the output, high speed is often used to achieve high shear in practice. Cutting, large length-to-diameter ratio screw to extend the processing process, etc., but it brings many problems such as high energy consumption, low efficiency and material degradation.

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