CN115891100B

CN115891100B - An extruder

Info

Publication number: CN115891100B
Application number: CN202211655035.XA
Authority: CN
Inventors: 王瑾; 彭冬冬; 钟旺
Original assignee: Wanhua Chemical Group Co Ltd
Current assignee: Wanhua Chemical Group Co Ltd
Priority date: 2022-12-22
Filing date: 2022-12-22
Publication date: 2025-01-07
Anticipated expiration: 2042-12-22
Also published as: CN115891100A

Abstract

The application provides an extruder which comprises a cylindrical barrel, wherein the barrel comprises a feeding section, a solid conveying section, a melting section and a homogenizing section which are sequentially connected in the axial direction, an axially extending screw rod is arranged in an inner cavity of a barrel lining, left spiral ribs extending from a first starting point to a first ending point are arranged on the inner wall of the barrel lining in a protruding mode, the left spiral ribs are arranged in a plurality of and axially spaced mode, right spiral ribs extending from a second starting point to a second ending point are arranged on the inner wall of the barrel lining in a protruding mode, the right spiral ribs are arranged in a plurality of and axially spaced mode, the left spiral ribs and the right spiral ribs are axially spaced mode, the first starting point and the second starting point are axially spaced mode on the same axis, the first ending point and the second ending point are axially spaced mode on the same axis, and the extruder enables materials to be mixed more fully, extruded products are plasticized more uniformly and the quality is more stable.

Description

Extruding machine

Technical Field

The invention belongs to the technical field of polymer extrusion, and particularly relates to an extruder.

Background

The mechanical equipment used for polymer molding processing is of a wide variety, such as extruders, injection molding machines, internal mixers, open mills, calenders, and the like. Among them, the extruder plays an important role in the polymer molding processing machinery. Extrusion molding has the advantage that a series of physicochemical changes of the polymer are continuously completed on an extruder at one time, and is an important method for polymer molding processing. It is counted that the yield of extrusion molded articles is the leading one in the polymer molding industry. Single screw extruders, as a common polymer extrusion apparatus, are tending to develop at high speed, high efficiency and large scale, and the solid melt plasticization capability is an important factor limiting its development.

Therefore, it is desirable to design an extruder for improved material mixing so that the extruded product plasticizes more uniformly and of a more consistent quality.

Disclosure of Invention

In view of some or all of the above technical problems existing in the prior art, an extruder is provided. The extruder enables materials to be mixed more fully, and extruded products are plasticized more uniformly and have more stable quality.

According to the invention, the technical scheme provided by the invention is as follows:

an extruder, comprising:

A cylindrical barrel, in the axial direction, the barrel comprises a charging section, a solid conveying section, a melting section and a homogenizing section which are connected in sequence,

A cylinder liner in contact with the inner cavity of the cylinder,

An axially extending screw disposed in the interior cavity of the barrel liner,

The inner wall of the cylinder liner is provided with a plurality of left spiral ribs extending from a first starting point to a first finishing point in a protruding mode, the left spiral ribs are axially arranged at intervals,

Right spiral ribs extending from the second starting point to the second ending point are arranged on the inner wall of the cylinder liner in a protruding mode, the right spiral ribs are arranged in a plurality of and axially spaced mode,

The left spiral rib and the right spiral rib are axially distributed at intervals, the first starting point and the second starting point are axially arranged at intervals on the same axis, and the first ending point and the second ending point are axially arranged at intervals on the same axis.

In one embodiment, the distribution density of the left and right helical ribs increases gradually in the direction from the charging section to the homogenizing section.

In one embodiment, the maximum value of the distance between adjacent left-hand helical ribs is 15-20% of the average diameter of the barrel liner, and the minimum value of the distance between adjacent left-hand helical ribs is 10-15% of the average diameter of the barrel liner, and the width of each left-hand helical rib is 1-5% of the average diameter of the barrel liner.

In one embodiment, the height of each of the left and right helical ribs is 1-5% of the average diameter of the barrel liner.

In one embodiment, the helix angle of each of the left and right helical ribs is 40-60 degrees.

In one embodiment, protruding nails are arranged on the sections of the screw corresponding to the melting section and the homogenizing section, and avoiding grooves for avoiding the protruding nails are arranged on the left spiral edge and the right spiral edge corresponding to the protruding nails.

In one embodiment, the protruding tack includes a fixed post for connection to the screw and a plow disposed on the fixed post, the pointed end of the plow passing through the relief slot relative to the broad head end.

In one embodiment, the plow comprises:

an arcuate surface extending over the pointed end to the broad end facing away from the fixed post, the arcuate surface projecting in a direction facing away from the fixed post,

The two connecting surfaces are arranged at the two axial ends of the arc-shaped surface, and the two connecting surfaces are gradually close to and overlap joint in the direction gradually close to the fixing column.

In one embodiment, a plurality of protruding nails are arranged on the outer wall of the screw rod, and one group of protruding nails in the same circumferential line and the other group of protruding nails in the same adjacent circumferential line are distributed in a quincuncial shape.

In one embodiment, the width of the relief groove is 1.1-1.5 times the maximum width dimension of the plow.

Compared with the prior art, the invention has the advantages that the grooves are formed between the adjacent left spiral edges or the adjacent right spiral edges by arranging the left spiral edges, the right spiral edges and other spiral edges protruding out of the cylinder liner on the inner wall of the cylinder liner, thereby being beneficial to improving the friction force between the material and the cylinder liner and further improving the conveying efficiency and the melting plasticizing capacity of the material. Further, through setting up left spiral arris and right spiral arris to because left spiral arris and right spiral arris are axially spaced to lay, in the material extrusion motion process, the material carries out the reposition of redundant personnel guide through left spiral arris or right spiral arris, can be from the spiral slot of one side selectively enter into the spiral slot of both sides, thereby, the material is in extrusion motion, can shunt and follow the spiral slot of different directions and move many times, has improved the mixing effect from this.

Drawings

Preferred embodiments of the present invention will be described in detail below with reference to the attached drawing figures, wherein:

FIG. 1 schematically shows a cross-sectional structural view of an extruder according to one embodiment of the present invention;

FIG. 2 is a sectional view schematically showing a part of the structure of an extruder according to one embodiment of the present invention;

FIG. 3 schematically illustrates a partial perspective view of an extruder in accordance with one embodiment of the present invention;

FIG. 4 is a cross-sectional view A-A of FIG. 2;

FIG. 5 schematically illustrates a protruding tack of one embodiment of the present invention;

fig. 6 is a B-B view of fig. 5.

In the drawings, like parts are designated with like reference numerals. The figures are not drawn to scale.

Detailed Description

In order to make the technical solution and advantages of the present invention more apparent, exemplary embodiments of the present invention will be described in further detail below with reference to the accompanying drawings. It will be apparent that the described embodiments are only some of the embodiments of the present invention and are not exhaustive of all embodiments. And embodiments of the invention and features of the embodiments may be combined with each other without conflict.

The application provides an extruder. As shown in fig. 1 to 4, the extruder includes a barrel 1, a barrel bushing 2, a screw 3, a left screw rib 4, and a right screw rib 5. The main body of the cylinder 1 is in a cylinder shape and mainly plays a role of basic support for the main body of the extruder. Referring to fig. 3, the cylinder 1 may be designed as a square cylinder, a circular cylinder, or the like according to actual needs. In the axial direction, the bowl 1 comprises a charging section 11, a solids conveying section 12, a melting section 13 and a homogenizing section 14, which are connected in sequence. It will be appreciated that an opening 15 for communicating with the interior cavity of the barrel liner 2 is provided in the charging section 11 of the barrel 1 for the addition of material. The cylinder liner 2 is sleeved in the inner cavity of the cylinder 1 in a contact manner and is mainly used for being contacted with a polymer to form a working cavity for accommodating extruded materials. The screw 3 is inserted into the inner cavity of the barrel bushing 2, in operation, the screw 3 rotates to convey material such that the material entering through the opening 15 moves axially through the charging section 11, the solids delivery section 12, the melting section 13 and the homogenization section 14 in sequence. As shown in fig. 3 and 4, the left spiral rib 4 is provided to protrude on the inner wall of the barrel liner 2 and extends in a left spiral form from the first start point 41 to the first end point 42. The right spiral rib 5 is provided on the inner wall of the barrel liner 2 in a protruding manner and extends in a right spiral from the second start point 51 to the second end point 52. Left helical groove 43 is formed between adjacent left helical ribs 4, and right helical groove 53 is formed between adjacent right helical ribs 5. Therefore, in the material transmission process, the left spiral edge 4 and the right spiral edge 5 play a certain role in blocking and guiding, so that the friction force between the material and the cylinder liner 2 can be improved, and the conveying efficiency and the melting plasticizing capacity of the material are improved. According to the application, the left spiral rib 4 and the right spiral rib 5 are arranged axially at a distance from each other. The first start point 41 and the second start point 51 are axially spaced apart from each other on the same axis, and the first end point 42 and the second end point are axially spaced apart from each other on the same axis. Preferably, one left-handed rib 4 starts moving 180 degrees in a left-handed fashion at first start point 41 to first end point 42 and one right-handed rib 5 starts moving 180 degrees in a right-handed fashion at second start point 51 to second end point. Thus, since the second start points 51 are staggered axially from the first start points 41, the left and right spiral grooves 43 and 53 communicate at both the start and end points. Thus, during the conveyance, the material may be introduced into the left spiral groove 43 through the left spiral rib 4 or into the right spiral groove 53 through the right spiral rib 5 at the communication point between the left spiral groove 43 and the right spiral groove 53, thereby splitting. Due to the arrangement of the left spiral ribs 4 and the right spiral ribs 5, materials can be intersected for many times and split for many times in the moving process, so that the mixing uniformity can be greatly improved, and the mixing effect is ensured.

Preferably, the distribution density of the left and right helical ribs 4, 5 increases gradually in the direction from the feeding section 11 to the homogenizing section 14. That is, the width (axial dimension) of the left-hand helical groove 43 formed between the adjacent left-hand helical ribs 4 varies in the axial direction, which varies such that the width of the left-hand helical groove 43 becomes smaller and smaller in the direction from the charging section 11 to the homogenizing section 14. The arrangement meets the material extrusion requirement adaptively, and the left spiral edge 4 and the right spiral edge 5 which are more and more dense at the downstream end can relatively improve the speed of diversion and mixing, thereby being beneficial to melting or improving the homogenization effect. For example, the maximum value of the distance between the adjacent left helical ribs 4 is 15 to 20%, for example 18%, of the average diameter of the barrel liner 2 (average of the inner diameter and the outer diameter of the barrel liner 2). While the minimum value of the distance between adjacent left helical ribs 4 is 10-15%, for example 18%, of the average diameter of the barrel liner 2. The width of each left helical rib 4 is 1-5%, for example 3%, of the average diameter of the barrel liner 2. While the height of the left helical rib 4 is 1-5% of the average diameter of the barrel liner 2. It will be appreciated that the arrangement of the right spiral rib 5 matches that of the left spiral rib 4 and that the height and width of both may be the same. The structure is reasonable, and the manufacturing and the production are easy.

The left and right helical ribs 4, 5 are plural, for example 4-20 each, although it will be understood that the application is not limited to the above arrangement, and that specific numbers may be planned and set according to the specific dimensions of the extruder, etc.

The helix angle of each left and right helical rib 4,5 is 40-60 degrees. The arrangement can ensure smooth extrusion of materials on one hand, and ensure that the material spiral edges produce optimal blocking and guiding effects on the materials on the other hand, thereby achieving the purpose of arranging the spiral edges 4 and 5. The helix angles of the left and right helical ribs 4 and 5 provided on the same extruder may be the same or different, and similarly, the helix angles of the left and right helical ribs 4 and 5 positioned adjacently and matched may be the same or different.

Protruding spikes 6 are provided on the screw 3 in sections corresponding to the melting section 13 and the homogenizing section 14. And the left spiral rib 4 and the right spiral rib 5 corresponding to the protruding nails 6 are provided with avoiding grooves 44 for avoiding the protruding nails. On the one hand, the protruding nails 6 are used for stirring materials and improving the mixing effect of the materials so as to ensure the plasticizing uniformity of the materials and improve the quality of extruded products, and on the other hand, especially, dead zones for the flow of the materials appear at the bottoms of the left spiral grooves 43 and the right spiral grooves 53, the protruding nails 6 can clean the materials gathered in the dead zones, so that the problems of poor mixing effect and long residence time of the gathered materials are avoided, the mixing effect of the materials is further improved, the plasticizing uniformity of the materials is further ensured, and the quality of extruded products is improved.

Preferably, as shown in fig. 5 and 6, the protruding spike 6 comprises a fixed post 61 and a plow 62. Wherein the fixing post 61 is cylindrical for connection to a screw. A plow 62 is provided at the free end of the fixed post 61. The plow 62 is configured as a plow, and the pointed end passes through the relief groove 44 in advance of the wide end. The pointed end contacts the material in advance compared with the wide end, at this time, the contact area is small, the friction force is low, the contact area is increased along with the gradual penetration of the plow 62 into the material, the friction force is correspondingly increased, and the stirring effect on the material is also enhanced. The plow 62 of the plow type structure can penetrate into the material more easily to stir the material, thereby reducing the requirement for the torque of the screw 3. Meanwhile, in the rotating process, the contact area between the plow 62 and the material is continuously changed, so that the material can be pushed and turned, the stirring efficiency is improved, and the material is ensured to be mixed more uniformly.

It is further preferred that the plow 62 includes an arcuate surface 621 extending from the pointed end to the broad end away from the fixed post 61, and two connecting surfaces 622 disposed at axial ends of the arcuate surface 621. The two connecting surfaces 622 are gradually brought closer to and overlap in a direction gradually approaching the fixing post 61. The arcuate surface 621 projects in a direction away from the fixed post 61 for better engagement with the arcuate inner wall of the barrel liner 2, thereby enhancing cleaning and agitation. The connection surface 622 extends in a slope manner to increase the width and strength of the plow 62, thereby increasing the stirring effect and ensuring the service life.

A plurality of protruding nails 6 are provided on the outer wall of the screw 3. Protruding staples 6 are defined as a group in the same circumferential line, for example, a group may comprise 3-10 protruding staples 6. And the protruding nails 6 between the adjacent protruding nail groups are distributed in a plum blossom shape. This setting can increase the stirring ability, helps the material more even. Of course, the plum blossom type arrangement may be performed between two groups.

As shown in fig. 3, the escape groove 44 extends in a direction perpendicular to the axial direction for escaping the protruding nail 6. And the width of relief groove 44 is 1.1-1.5 times the maximum width dimension of plow 62. While the height of the relief groove 44 corresponds to the height of the helical rib. The arrangement structure is optimized and easy to realize.

The screw 3 may have a diameter of, for example, 20-200mm and an aspect ratio of 5-40, and the number of flights may be single-ended, double-ended or multi-ended.

According to the extruder, the spiral ribs 4 and 5 are arranged, so that friction shearing action is formed between the spiral ribs 4 and 5 and materials in the material extrusion process, heat is provided for melting the materials, the melting plasticizing capacity of the extruder is enhanced, and the specific energy consumption of the extruder is reduced; in addition, the material is continuously split by the raised spiral ribs 4 and 5 in the barrel liner 2, and can selectively enter the two spiral grooves from one thread groove, so that the materials are fully mixed. The arrangement of the protruding nails can generate friction shearing force with materials, the fluidity of the materials is improved, and the self-cleaning capacity of the extruder is realized by reducing the flowing dead zone.

While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. It is therefore intended that the following claims be interpreted as including the preferred embodiment and all alterations and/or modifications that fall within the scope of the invention, and that are intended to be included within the scope of the invention.

Claims

1. An extruder, which comprises a die-casting die, characterized by comprising the following steps:

A cylinder liner in contact with the inner cavity of the cylinder,

An axially extending screw disposed in the interior cavity of the barrel liner,

The left spiral edge and the right spiral edge are axially arranged at intervals, the first starting point and the second starting point are axially arranged at intervals on the same axis, the first ending point and the second ending point are axially arranged at intervals on the same axis, the left spiral edge starts to move 180 degrees in a left spiral mode at the first starting point to reach the first ending point, the right spiral edge starts to move 180 degrees in a right spiral mode at the second starting point to reach the second ending point, and the spiral angle of each left spiral edge and each right spiral edge is 40-60 degrees.

2. The extruder of claim 1 wherein the distribution density of the left and right flights increases gradually in a direction from the feed section to the homogenizing section.

3. The extruder of claim 2 wherein the distance between adjacent left-hand helical ribs has a maximum value of 15-20% of the average diameter of the barrel liner and the distance between adjacent left-hand helical ribs has a minimum value of 10-15% of the average diameter of the barrel liner, and the width of each left-hand helical rib is 1-5% of the average diameter of the barrel liner.

4. An extruder according to any one of claims 1 to 3, wherein the height of each of the left and right helical ribs is 1-5% of the average diameter of the barrel liner.

5. An extruder according to claim 2 or 3, wherein protruding nails are provided on the sections of the screw corresponding to the melting section and the homogenizing section, and avoiding grooves for avoiding the protruding nails are provided on the left-hand screw rib and the right-hand screw rib corresponding to the protruding nails.

6. The extruder of claim 5 wherein said protruding spike comprises a fixed post for connection to said screw and a plow disposed on said fixed post, a pointed end of said plow passing through said relief groove relative to a broad head end.

7. An extruder according to claim 6, characterized in that the plow comprises:

8. The extruder of claim 5 wherein a plurality of said protruding spikes are provided on the outer wall of said screw, one set of said protruding spikes in the same circumferential line being arranged in a quincuncial pattern with another set of said protruding spikes in an adjacent same circumferential line.

9. An extruder according to claim 6 or claim 7, wherein the width of the relief groove is 1.1-1.5 times the maximum width dimension of the plow.