CN112339156A - Shunting stretching screw element and screw combination thereof - Google Patents
Shunting stretching screw element and screw combination thereof Download PDFInfo
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- CN112339156A CN112339156A CN202011130642.5A CN202011130642A CN112339156A CN 112339156 A CN112339156 A CN 112339156A CN 202011130642 A CN202011130642 A CN 202011130642A CN 112339156 A CN112339156 A CN 112339156A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
- B29B7/00—Mixing; Kneading
- B29B7/30—Mixing; Kneading continuous, with mechanical mixing or kneading devices
- B29B7/34—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices
- B29B7/38—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices rotary
- B29B7/40—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices rotary with single shaft
- B29B7/42—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices rotary with single shaft with screw or helix
- B29B7/428—Parts or accessories, e.g. casings, feeding or discharging means
- B29B7/429—Screws
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
- B29B7/00—Mixing; Kneading
- B29B7/30—Mixing; Kneading continuous, with mechanical mixing or kneading devices
- B29B7/34—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices
- B29B7/38—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices rotary
- B29B7/46—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices rotary with more than one shaft
- B29B7/48—Mixing; Kneading continuous, with mechanical mixing or kneading devices with movable mixing or kneading devices rotary with more than one shaft with intermeshing devices, e.g. screws
- B29B7/488—Parts, e.g. casings, sealings; Accessories, e.g. flow controlling or throttling devices
- B29B7/489—Screws
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- Extrusion Moulding Of Plastics Or The Like (AREA)
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Abstract
本发明公开了一种分流拉伸螺杆元件及其螺杆组合，所述分流拉伸螺杆元件整体为一个中空柱状的拉伸块，芯部为与螺杆芯轴相连的连接孔，外表面沿周向平行设置若干分隔棱，分隔棱间为拉伸槽，拉伸槽与机筒内壁面的间隙形成径向拉伸流道；此外还可在分隔棱的顶端设置一个斜侧面，带有斜侧面的分隔棱顶端与机筒内壁的间隙形成周向拉伸流道；螺杆工作时，在径向和轴向拉伸流道的拉伸力场作用下，对物料进行分流拉伸混合，增强混炼塑化、分布分散混合效果。与剪切流比，拉伸流混合有能效高、不受粘度比限制、温升小的特点，产生更好的分散和分布效果。本发明的拉伸块，可与传统螺杆对接，无需添加额外设备或控件，拆装方便，适用多种加工设备。
The invention discloses a split-flow stretching screw element and a screw combination thereof. The split-flow stretching screw element is a hollow cylindrical stretching block as a whole, the core part is a connecting hole connected with the screw core shaft, and the outer surface is along the circumferential direction. A number of dividing edges are arranged in parallel, and there are stretching grooves between the dividing edges, and the gap between the stretching groove and the inner wall of the barrel forms a radial stretching flow channel; The gap between the top of the separating edge and the inner wall of the barrel forms a circumferential stretching flow channel; when the screw is working, under the action of the stretching force field of the radial and axial stretching flow channels, the material is divided and stretched to enhance the mixing. Plasticizing, dispersing and mixing effects. Compared with shear flow, extensional flow mixing has the characteristics of high energy efficiency, not limited by viscosity ratio, and small temperature rise, resulting in better dispersion and distribution effect. The stretching block of the present invention can be docked with a traditional screw without adding additional equipment or controls, is convenient for disassembly and assembly, and is suitable for various processing equipment.
Description
Technical Field
The invention relates to a high polymer plasticizing and mixing device, in particular to a shunting and stretching screw element and a screw combination thereof.
Background
During the processing and plastification of the screw, the conveying and distributive mixing capability of the material can be controlled by appropriately selecting the type and geometry of the screw elements, with the majority of dispersive mixing occurring in the shear flow-dominated kneading blocks.
With the development of polymer material science, the traditional screw elements mainly based on shearing cannot meet the processing requirements, for some thermally unstable resins such as PVC, PPC and the like, excessive shearing can generate a large amount of viscosity to dissipate heat, possibly cause thermal degradation of a matrix, and pure shearing is not beneficial to processing a blend with higher viscosity, so that the important problem of screw processing is how to ensure that the shearing heat is reduced while the mixing effect is increased.
In recent years, in order to introduce a tensile force field or generate a chaotic force field in high polymer plasticizing processing equipment, a differential screw extrusion technology, which generates the chaotic force field through the speed difference of two screws, a hollow screw, introduces the tensile force field in the hollow part of the screw by adopting a convergent-divergent flow channel, an eccentric rotor extruder, realizes volume stretching through the volume periodic change of a containing cavity of a rotor and a stator to generate a stretching dominant flow field and other novel processing equipment, is provided, but the equipment usually relates to the transformation of the whole screw or the extruder equipment, has a complex structure, is difficult to prepare, has high manufacturing cost, is mainly applied to a laboratory at present, and is difficult to realize the mass production of the equipment.
Disclosure of Invention
Aiming at the problems of poor mixing effect, temperature rise, complex structure and the like in the prior art, the invention provides a shunting and stretching screw element, which adopts the following technical scheme:
a kind of shunting draws the screw element, its whole is a hollow cylindrical stretching block, its core is the attachment hole used for linking with spindle of the screw rod, its external surface sets up several and separates arrises in parallel circumferentially, separate the arrises and is identical along the radial height of stretching block; and a stretching groove is arranged between the separating edges, a gap between the stretching groove and the inner wall surface of the machine barrel forms a stretching flow channel along the radial direction of the screw, and the radial stretching flow channel is a semi-convergent-divergent stretching flow channel which is narrow in the middle and wide at two ends along the axial direction of the screw.
During the rotation of the screw, the material flows through the stretching block and is divided into a plurality of material flows by the separating edges, so that the material flows are disturbed, and the material is accelerated and homogenized; the radial stretching flow channel formed by the stretching groove and the inner wall surface of the machine barrel generates a strong stretching force field effect, and material flows are dispersed and converged to achieve an excellent distribution, dispersion and mixing effect.
Furthermore, an inclined side face can be arranged at the top end of the separating edge, at the moment, a circumferential stretching flow channel can be formed by the gap between the top end of the separating edge with the inclined side face and the inner wall of the machine barrel, so that the materials are not only stretched and mixed in the original radial direction, but also stretched and mixed in the circumferential direction, are both subjected to strong stretching force field action in the radial direction and the circumferential direction, and then are converged again. The materials are repeatedly shunted, stretched and converged, and the distribution, dispersion, mixing and plasticizing effects in the processing process are enhanced.
Further, the semi-convergent-divergent stretch flow path includes an intermediate convergent section LCFirst diverging sections L at both ends1And a second diverging section L2And the outer contour line forming the semi-convergent-divergent stretching flow passage is a straight line, wherein the first divergent section L1Has an inlet angle of phi1Second divergent section L2Has an inlet angle of phi2. Convergence section LCThe corresponding flow channel depth value is Wc, and the first divergent section L1And a second diverging section L2The maximum depth position of the flow channel is Wu, and the Wu is required to be larger than Wc; if a is the convergence ratio, then a is Wu/Wc>1; the larger a is, the larger the extrusion and stretching action of the material passing through the convergent-divergent channel is, the more obvious the extrusion and stretching action is usually, the convergence ratio is more than 2, and the convergence ratio a and the inlet angle phi are determined according to the specification of the screw and the material characteristics1、Φ2Is preferably carried out to achieve the best effect, wherein phi1、Φ2Preference can be given to working at from 0 to 90 ℃.
Preferably, the first divergent section L1And a second diverging section L2Symmetrically distributed on both sides of the convergent section Lc, and the first divergent section L1And a second diverging section L2Equal in length and having a diameter of1＝Φ2。
Optionally, the semi-convergent-divergent stretching flow channel has a semi-hyperbolic curve on the side close to the stretching groove along the axial section of the screw.
Further, the half hyperbola is represented by the equation x ((z-L/2)2-Vc)/k specifies: wherein L is the length of the stretching block, Vc is the width of the narrowest part of the stretching flow channel along the axial section of the screw,z is an axial coordinate of a point on the inner wall surface of the machine barrel, x is the width of the stretching flow channel corresponding to the z point on the axial section of the screw, and k is a constant; the length L of the block varies depending on the screw gauge and the number of grooves.
One advantage of using a hyperbolic converging flow path is that a constant strain rate can be created along the centerline of the hyperbola, i.e., the axial direction of the half channel, near the inside wall surface of the barrel. According to theoretical design, the parameters are variable, and different parameters can be combined and optimized to achieve the best effect depending on actual processing requirements.
Furthermore, the number of the separating edges is not less than 4, the thickness of the edges is 1 to 5 millimeters, and the specific numerical value can be optimally designed according to the specification of the screw and the characteristics of the processed high polymer material.
Furthermore, the length of the separating edges on the stretching block can be changed according to specific requirements and processing conditions; the part of the total length of the stretching block, which is provided with the separation edges, is called a stretching section, and the part of the stretching block, which is not provided with the separation edges, is a hollow cylinder and is called a non-stretching section; the stretching block includes a stretching section and a non-stretching section. This is the case primarily in twin-screw or multi-screw processing. Preferably, the length of the stretched section and the length of the non-stretched section are equal.
In the double-screw processing, the stretching sections and the non-stretching sections of the stretching blocks arranged on the left screw and the right screw are staggered, so that a certain meshing distance is ensured, and the movement of the screws cannot interfere; in the multi-screw processing, the stretching sections and the non-stretching sections of the stretching blocks arranged on the plurality of screws are staggered, a certain meshing distance is ensured, and the movement of the screws cannot interfere.
It is another object of the present invention to provide a screw assembly comprising the split draw screw element of the present invention, comprising a screw conveying section and a plurality of draw blocks mounted in series on a screw spindle; preferably, the number of the stretching blocks is 3. A plurality of stretching blocks are continuously installed on the screw mandrel, and materials are repeatedly shunted, stretched and converged, so that the mixing plasticizing and distribution dispersion mixing effects are further enhanced.
Another object of the present invention is to provide another screw assembly comprising the split draw screw element of the present invention, comprising a reverse conveying element, a plurality of draw blocks, a conveying element, a plurality of kneading blocks staggered at an angle of 90 ° and a plurality of kneading blocks staggered at an angle of 60 ° sequentially mounted on the shaft core of the screw; wherein the stretching block comprises a stretching section and a non-stretching section, and the reverse conveying element is positioned at the outlet position of the screw mixing section.
It should be noted that the split-flow stretch screw elements of the present invention can be interfaced with a conventional screw without interrupting its normal function or adding additional equipment systems or controls, and are therefore suitable for use in extrusion or injection molding equipment that operates with a screw, including: single screw extruder, double screw extruder, multiple screw extruder, injection molding machine.
The invention has the following outstanding advantages:
1. according to the device, a separation ridge and a stretching groove are arranged on a stretching block, and a gap between the stretching groove and the inner wall surface of a machine barrel forms a stretching flow channel along the radial direction of a screw rod; meanwhile, an inclined side face can be arranged at the top end of the separation edge, and a gap between the top end of the separation edge with the inclined face and the inner wall face of the machine barrel forms a stretching flow channel along the circumferential direction of the screw; when the screw rod works, the flow channel is stretched in the circumferential direction and the radial direction of the screw rod, the materials are divided, stretched and mixed, and the mixing plasticizing, distributing, dispersing and mixing effects in the high polymer plasticizing processing process are enhanced.
2. Compared to shear flow, extensional flow mixing has the following advantages: the energy efficiency is higher than the shear flow; is not limited by viscosity ratio; the temperature rise of the draw stream is only 1-3 ℃; resulting in better dispersion and distributive mixing.
3. The stretching block adopted by the invention can be used for a traditional screw system, does not need to add an additional equipment system or a control to realize high polymer extrusion processing or injection molding processing, is convenient to disassemble and assemble, and is suitable for various processing equipment.
Drawings
Fig. 1 is a schematic perspective view of a split-flow stretching screw element according to embodiment 1 of the present invention.
Fig. 2 is a cross-sectional view of an embodiment 1 of a split-flow draw screw element of the present invention in an operating condition.
Fig. 3 is a cross-sectional view taken along a-a of fig. 2.
Fig. 4 is a schematic perspective view of a split-flow stretching screw element according to embodiment 2 of the present invention.
Fig. 5 is a cross-sectional view of an embodiment 2 of a split-flow draw screw element of the present invention in an operating condition. (the lower right corner enlarged portion shows a circumferential stretching flow channel 8)
FIG. 6 is a schematic view of an embodiment of a semi-convergent-divergent stretch flow channel of the present invention.
FIG. 7 is a schematic view of another embodiment of a semi-convergent-divergent stretch flow channel of the present invention.
FIG. 8 is a perspective view of a twin screw of example 3 of a flow dividing drawing screw element of the present invention.
Fig. 9 is a schematic structural view of a screw assembly 1 of the present invention.
Fig. 10 is a schematic structural view of a screw assembly 2 of the present invention.
In the figure:
the device comprises a stretching block 1, a connecting hole 2, a separating edge 3, a stretching groove 4, a radial stretching flow channel 5, a screw mandrel 6, a machine barrel 7, a circumferential stretching flow channel 8, an inclined side surface 9, a screw 10, a stretching section 11, a non-stretching section 12, a reverse conveying element 61, a conveying element 62, a kneading block 63 with a staggered angle of 90 degrees and a kneading block 64 with a staggered angle of 60 degrees.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.
Fig. 1-3 show an embodiment 1 of a split-flow stretching screw element of the present invention, wherein fig. 1 is a schematic perspective view of the embodiment 1, the embodiment is a hollow cylindrical stretching block 1 as a whole, a plurality of separating ribs 3 are arranged on the outer surface of the stretching block 1 in parallel along the circumferential direction, and the core of the stretching block 1 is a connecting hole 2 for connecting with a screw mandrel 6; fig. 2 shows a state of use of the embodiment, in which the stretching block 1 is inserted into the screw mandrel 6 through the connecting hole 2 and then into the cylinder 7. The separating edges 3 are consistent in height along the radial direction of the stretching block; and a stretching groove 4 is formed between each separating edge 3, a gap between the stretching groove 4 and the inner wall surface of the machine barrel 7 forms a stretching flow channel 5 along the radial direction of the screw, and the radial stretching flow channel 5 is a semi-convergent-divergent stretching flow channel with a narrow middle part and two wide ends along the axial direction of the screw.
Fig. 4-5 show an embodiment 2 of a split-flow drawing screw element according to the invention, wherein fig. 4 is a schematic perspective view and fig. 5 shows a view of the use of the embodiment, in which an oblique flank 9 is provided at the tip of the separating edge 3, in which the drawing block 1 is inserted into the screw spindle 6 via the connecting bore 2 and then into the barrel 7. At this moment, a circumferential stretching flow channel 8 is formed in a gap between the top end of the separation edge 3 with the inclined side surface 9 and the inner wall of the machine barrel, (the separation edge 3 and the circumferential stretching flow channel 8 are enlarged and shown in the lower right corner of fig. 5) so that the materials are not only stretched and mixed in the original radial direction, but also are stretched and mixed in the circumferential direction, and the materials are repeatedly shunted, stretched and converged to strengthen the distribution, dispersion, mixing and plasticizing effects of the processing process.
The semi-convergent-divergent elongate flow path may take a variety of forms, two examples being provided herein.
FIG. 6 is a cross-sectional view taken along the axial direction of the screw of one embodiment of a semi-converging-diverging elongation channel of a split-flow elongation screw element of the present invention including an intermediate converging section LCFirst diverging sections L at both ends1And a second diverging section L2(ii) a In this embodiment, the outer contour line forming the semi-convergent-divergent stretch flow path is a straight line, wherein the first divergent section L1Has an inlet angle of phi1Second divergent section L2Has an inlet angle of phi2. Convergence section LCThe corresponding flow channel depth value is Wc, and the first divergent section L1And a second diverging section L2The maximum depth position of the flow channel is Wu, and the Wu is required to be larger than Wc; if a is the convergence ratio, then a is Wu/Wc>1; the larger a is, the larger the extrusion and stretching action of the material passing through the convergent-divergent channel is, the more obvious the extrusion and stretching action is usually, the convergence ratio is more than 2, and the convergence ratio a and the inlet angle phi are determined according to the specification of the screw and the material characteristics1、Φ2Is preferably carried out to achieve the best effect, wherein phi1、Φ2Preference can be given to working at from 0 to 90 ℃.
Preferably, the first divergent section L1And a second diverging section L2Symmetrically distributed on both sides of the convergent section Lc, and the first divergent section L1And a second diverging section L2Equal in length and having a diameter of1＝Φ2。
Furthermore, when the semi-convergent-divergent stretching flow channel is selected, the contour line of the flow channel is a straight line, and round corners can be arranged at each break point formed by the straight line, so that the resistance of the material flow is reduced, and the material flow is prevented from being burnt due to overheating for too long retention time.
FIG. 7 is an axial cross-sectional view of another embodiment of a semi-convergent-divergent drawing channel of a flow-dividing drawing screw element of the present invention, wherein the profile curve of the cross-section in the screw axial direction on the side close to the drawing groove 4 is a semi-hyperbolic curve, and further, the semi-hyperbolic curve is represented by the equation x ═ ((z-L/2)2-Vc)/k specifies: wherein, L is the length of the stretching block 1, Vc is the width of the narrowest part of the stretching flow channel along the axial section of the screw, z is the axial coordinate of a point on the inner wall surface of the machine barrel 7, x is the width of the stretching flow channel corresponding to the z point along the axial section of the screw, and k is a constant; the length L of the block varies depending on the screw gauge and the number of grooves.
One advantage of using this hyperbolic converging flow path is that a constant strain rate can be created along the centerline of the hyperbola, i.e., the axial direction of the half channel, near the inside wall surface of the barrel. According to theoretical design, the parameters are variable, and different parameters can be combined and optimized to achieve the best effect depending on actual processing requirements.
In general, the length of the stretching block is determined according to the specification of the screw and the number of grooves, and the number of the separation edges 3 is not less than 4; the thickness of the edge is 1 to 5 mm. These parameters can be varied and optimized for the particular screw specifications and processing requirements.
Fig. 8 shows a perspective view of an embodiment 3 of a split-flow stretching screw element of the present invention, in which the stretching block 1 includes two segments, a stretching segment 11 and a non-stretching segment 12, wherein the stretching segment 11 is provided with a separation rib 3 and a stretching groove 4, and the non-stretching segment 12 is a hollow cylinder without the separation rib 3 and the stretching groove 4. The lengths of the stretched and non-stretched segments 11 and 12 may be equal. Generally, the embodiment is applied to a double-screw extruder, and in order to ensure the circumferential meshing gap between the left screw and the right screw, when the screws work, the stretching sections 11 and the non-stretching sections 12 of the left screw and the right screw are staggered, and meanwhile, a certain axial meshing distance is ensured, and the movement of the screws cannot interfere. Likewise, the tensile block of example 3 can also be used in a multi-screw extruder.
The block 1 according to the invention can be adapted to different screw combinations by incorporating different screws and screw elements, two combinations being provided here.
Fig. 9 shows a screw assembly 1 comprising a split-flow drawing screw element of the present invention, comprising a screw conveying section 10 and the drawing block 1 of example 2, wherein the top end of the drawing block 1 has an oblique side surface, three drawing blocks 1 are continuously mounted on a screw mandrel 6, the material is divided into a plurality of material flows by dividing ribs 3 when flowing through the drawing block 1, the material is forced to pass through a semi-convergent-divergent flow passage formed by a drawing groove 4 and the inner wall surface of a machine barrel by forward conveying pressure from an extruder to form a radial drawing flow passage, and simultaneously, the material passes through a screw circumferential drawing flow passage formed by the top end of the dividing rib 3 with the oblique side surface and the inner wall surface of the machine barrel 7 during rotation of the screw, and is subjected to strong drawing force fields in the radial direction and the circumferential direction, and then. The materials are repeatedly shunted, stretched and converged, and the distribution, dispersion, mixing and plasticizing effects in the processing process are enhanced. Of course, the stretching blocks 1 in the present embodiment combination may also be selected from the stretching blocks of embodiment 1, and in addition, the number of the stretching blocks 1 may also not be limited to three, for example, 2 to 4 may also be optional.
FIG. 10 shows another screw assembly 2 comprising a split draw screw element of the present invention comprising a counter conveying element 61, a plurality of draw blocks 1, a conveying element 62, a plurality of kneading blocks 63 staggered by an angle of 90 degrees, and a plurality of kneading blocks 64 staggered by an angle of 60 degrees, mounted in sequence on the axis of the screw; wherein the stretching block 1 comprises a stretching section 11 and a non-stretching section 12, and the reverse conveying element 61 is positioned at the outlet position of the screw mixing section.
The material enters the barrel of the extruder through the hopper and is conveyed forward under the action of the rotation of the screw, while the material is still in the solid state, although the surface of the solid particles starts to be sticky due to the strong frictional heat effect when the plastic in contact with the inner wall of the barrel 7 approaches or reaches the viscous flow temperature near the end, but the melting does not start. Through repeated shearing and mixing of the kneading blocks 64 with the staggered angle of 60 degrees and the kneading blocks 63 with the staggered angle of 90 degrees, the materials are subjected to larger friction shearing and heat transfer of a machine barrel, fully melted and plasticized, solid particles are basically melted, at the moment, the materials are in a fluid state and are conveyed into a mixing section through the conveying element 62, the fluid is subjected to repeated shunting, stretching and converging effects of the shunting and stretching screw elements, the sizes of all components are further refined and uniform, and the mixing, plasticizing and distributing, dispersing and mixing effects are enhanced. The reverse conveying element 61 positioned at the outlet of the mixing section can form back pressure, ensure enough pressure to enable fluid to fill the stretching flow channel, increase the retention and distribution time of particles in the shunting stretching screw element and strengthen the stretching and mixing effect.
Similarly, in the embodiment of the screw combination, the number of the stretching blocks and the number and the types of the two kneading blocks can be optimally selected according to the specific requirements of screw processing.
The above-mentioned embodiments are only for the purpose of illustrating and explaining the preferred embodiments of the technical solution and the working principle of the present invention, and in fact, the embodiments of the present invention have many different forms and combinations, which are not limited by the above-mentioned embodiments, and any other changes, modifications, substitutions, combinations, simplifications, which are made without departing from the spirit and principle of the present invention, should be regarded as equivalents, and all of them are included in the protection scope of the present invention.
Claims (10)
1. A split-flow stretching screw element is integrally a hollow cylindrical stretching block (1); the screw rod stretching block is characterized in that the core part of the stretching block (1) is a connecting hole (2) connected with a screw rod mandrel (6), a plurality of separating edges (3) are arranged on the outer surface of the stretching block (1) in parallel along the circumferential direction, and the radial heights of the separating edges (3) along the stretching block (1) are consistent; and a stretching groove (4) is arranged between the separating edges, a radial stretching flow channel (5) is formed by a gap between the stretching groove (4) and the inner wall surface of the machine barrel (7), and the radial stretching flow channel is a semi-convergent-divergent stretching flow channel with a narrow middle part and two wide ends.
2. A split-flow drawing screw element according to claim 1, characterised in that the top end of the separating rib (3) is provided with a bevelled side surface (9).
3. A split-flow draw screw element as claimed in any one of claims 1 or 2, wherein said semi-converging-diverging draw runner comprises an intermediate converging section LCFirst diverging sections L at both ends1And a second diverging section L2And the outer contour line forming the semi-convergent-divergent stretching flow passage is a straight line; let convergence section LCThe depth value of the flow passage is Wc, and the first divergent section L1And a second diverging section L2The maximum depth of the flow channel is Wu, which is required to be larger than Wc.
4. A split-flow draw screw element as claimed in claim 3, wherein said first divergent section L of said semi-convergent-divergent draw runner1And a second diverging section L2The lengths are equal.
5. A flow-dividing drawing screw element according to any one of claims 1 or 2, characterized in that the profile curve of the semi-convergent-divergent drawing flow path in the axial direction of the screw on the side close to the drawing groove (4) is a semi-hyperbolic curve.
6. A flow-splitting drawing screw element according to claim 5, wherein said half hyperbola is given by the equation x ((z-L/2)2-Vc)/k specifies: wherein L is the length of the stretching block (1), Vc is the width of the narrowest part of the stretching flow channel along the axial section of the screw, z is the axial coordinate of a point on the inner wall surface of the machine barrel (7), x is the width of the stretching flow channel corresponding to the z point along the axial section of the screw, and k is a constant.
7. A tapping stretch screw element according to any one of claims 1 or 2, characterised in that the number of said separating ribs (3) is not less than 4 and the rib thickness is 1 to 5 mm.
8. A split-flow drawing screw element according to any one of claims 1 or 2, characterised in that the drawing block (1) comprises a drawing section (11) and a non-drawing section (12); wherein the stretching section (11) is provided with a separation ridge (3) and a stretching groove (4), and the non-stretching section (12) is a hollow cylinder.
9. A screw assembly comprising a split-flow stretch screw element according to any one of claims 1 to 8, comprising a screw conveying section (10) and not less than two stretch blocks (1), said stretch blocks (1) being mounted in series on a screw mandrel (6) of the screw conveying section (10).
10. A screw assembly comprising the split draw screw element of claim 8, comprising a counter conveying element (61), a plurality of draw blocks (1), a conveying element (62), a plurality of kneading blocks (63) staggered by an angle of 90 ° and a plurality of kneading blocks (64) staggered by an angle of 60 ° mounted in sequence on the screw shaft core.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011130642.5A CN112339156A (en) | 2020-10-21 | 2020-10-21 | Shunting stretching screw element and screw combination thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011130642.5A CN112339156A (en) | 2020-10-21 | 2020-10-21 | Shunting stretching screw element and screw combination thereof |
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| Publication Number | Publication Date |
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| CN112339156A true CN112339156A (en) | 2021-02-09 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011130642.5A Pending CN112339156A (en) | 2020-10-21 | 2020-10-21 | Shunting stretching screw element and screw combination thereof |
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| CN (1) | CN112339156A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115157591A (en) * | 2022-06-21 | 2022-10-11 | 华南理工大学 | A kind of alternating stretching and kneading element and method |
| CN116175931A (en) * | 2023-04-28 | 2023-05-30 | 广东工业大学 | A wheel-shaped stretching screw for a twin-screw extruder and an engaging method thereof |
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| US6962431B1 (en) * | 2000-11-08 | 2005-11-08 | Randcastle Extrusion System, Inc. | Extruder mixer |
| CN107471567A (en) * | 2017-09-30 | 2017-12-15 | 佛山市顺德区震德精密机械有限公司 | The screw mixing element of injection machine |
| CN214238972U (en) * | 2020-10-21 | 2021-09-21 | 华南理工大学 | A split-flow stretching screw element and screw combination thereof |
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2020
- 2020-10-21 CN CN202011130642.5A patent/CN112339156A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6962431B1 (en) * | 2000-11-08 | 2005-11-08 | Randcastle Extrusion System, Inc. | Extruder mixer |
| CN107471567A (en) * | 2017-09-30 | 2017-12-15 | 佛山市顺德区震德精密机械有限公司 | The screw mixing element of injection machine |
| CN214238972U (en) * | 2020-10-21 | 2021-09-21 | 华南理工大学 | A split-flow stretching screw element and screw combination thereof |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115157591A (en) * | 2022-06-21 | 2022-10-11 | 华南理工大学 | A kind of alternating stretching and kneading element and method |
| CN115157591B (en) * | 2022-06-21 | 2023-10-27 | 华南理工大学 | An alternating stretching and mixing element and method |
| CN116175931A (en) * | 2023-04-28 | 2023-05-30 | 广东工业大学 | A wheel-shaped stretching screw for a twin-screw extruder and an engaging method thereof |
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