Double-layer roiling wing nuclear fuel assembly positioning grillwork based on additive manufacturing

Abstract

The invention discloses a double-layer roiling wing nuclear fuel assembly positioning grillwork based on additive manufacturing. The double-layer roiling wing nuclear fuel assembly positioning grillwork comprises an internal grillwork unit, an edge grillwork unit and a corner grillwork unit, wherein the internal grillwork units are mutually connected to form a square matrix; the edge grillwork units extend along the four sides of the square matrix and surround the edges, except for the four corners, of the square matrix; the edge grillwork units located at the ends of all the edges are connected with the corner grillwork units to achieve corner transition. The grillwork units are connected through partially overlapped boundaries; the internal unit grillwork, the edge grillwork units and the corner grillwork units are respectively provided with eight, four and three stirring wings in two layers; the whole positioning grillwork is integrally formed by metal 3D printing from bottom to top, and zirconium alloy or high-temperature alloy is selected as a material; the effects that the stirring wings are longer and the stirring range is larger are achieved, meanwhile, the fuel rods and the positioning grillwork are convenient to assemble, the manufacturing difficulty and cost are reduced, and the design and manufacturing period is shortened.

Description

Technical Field

[0001] The present invention relates to the technical field of nuclear fuel assemblies, and in particular to a double-layer slurry wing nuclear fuel assembly positioning grid based on additive manufacturing. Technical Background

[0002] As the core component of a nuclear reactor, a nuclear fuel assembly consists of multiple fuel elements, control rod guide tubes, upper and lower tube sockets, and a spacer grid. Its core function is to maintain the regular spatial arrangement of the nuclear fuel bundle. During a nuclear reaction, coolant flows at high speed through the gaps between the fuel rods, continuously dissipating fission heat energy and creating high-temperature and high-pressure conditions. This characteristic makes reactor operational safety closely related to the component material and structural properties.

[0003] The positioning grid, the core device that constrains the spatial positioning of the fuel rods, is designed to ensure precise control of the rod bundle spacing. The grid's position must be fixed during the installation process before the fuel rods are inserted into the array. This requires the grid structure to have excellent assembly adaptability. Reactor heat transfer efficiency is significantly affected by the direction and velocity of the coolant flow, so the grid must provide fluid guidance. The temperature fluctuations, turbulence, and vibrations generated by the coolant flowing through the grid place significant demands on the grid's mechanical strength.

[0004] Existing spacer grids, such as the patent application titled "A Strip, Nuclear Fuel Spacer Grid, and Nuclear Fuel Assembly" (publication number CN204884577U) and the patent application titled "Spacer Grid and Fuel Assembly with Streamlined Low-Pressure Drop Flow Channels" (publication number CN104318962A), generally utilize an inner and outer composite strip structure. Positioning bosses and elastic elements are placed on either side of the outer strip to precisely clamp and position the fuel bundle. The inner strip, in addition to a similar structure, typically incorporates slurry fins along its edges. These multi-zoned slurry fins induce lateral coolant flow to optimize flow distribution. This design presents structural complexity, making manufacturing challenging. Furthermore, due to the miniaturized size, precision control during assembly becomes increasingly challenging, leading to a reduction in structural strength and performance. Summary of the Invention

[0005] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a double-layer slurry wing nuclear fuel assembly positioning grid based on additive manufacturing, which can achieve the effect of larger hollow area and longer slurry wing, and use the characteristics of additive manufacturing technology to design an integrated positioning and clamping clamping structure, which facilitates the assembly of fuel rods and positioning grids, reduces manufacturing difficulty and cost, and shortens the design and manufacturing cycle.

[0006] In order to achieve the above-mentioned purpose, the design scheme adopted by the present invention is:

[0007] A double-layer scrambling wing nuclear fuel assembly positioning grid based on additive manufacturing includes internal grid units 1, edge grid units 2, and corner grid units 3. The internal grid units 1 are interconnected to form a square array; the edge grid units 2 extend along the four sides of the square array and surround the edges of the square array excluding the four corners; the edge grid units 2 at the end of each side are respectively connected to the corner grid units 3 to achieve edge and corner transitions; the grid units are connected by partially overlapping boundaries;

[0008] The inner cell frame 1, edge grid unit 2, and corner grid unit 3 respectively have two layers of eight, four, and three stirring wings;

[0009] The positioning grid is integrally formed from bottom to top by metal 3D printing, and the material is zirconium alloy or high-temperature alloy.

[0010] The internal grid unit 1 includes a first hollow guide ring 1-4 in the middle layer, and four first upper torsion stirring wings 1-3 grow upward from its upper edge. The width of the first upper torsion stirring wings 1-3 gradually decreases upward and twists outward, and finally connects with the top first upper hollow frame ring 1-2. Four first upper claw-type elastic clamping parts 1-1 are evenly distributed inside the first upper hollow frame ring 1-2; four first lower torsion stirring wings 1-5 grow downward from the lower edge of the first hollow guide ring 1-4. The width of the first lower torsion stirring wings 1-5 gradually decreases downward and twists outward, and finally connects with the bottom first lower hollow frame ring 1-7. The arrangement position of the first lower torsion stirring wings 1-5 and the first upper torsion stirring wings 1-3 has an angle difference of 15°. Four first lower claw-type elastic clamping parts 1-6 are evenly distributed inside the first lower hollow frame ring 1-7. The configuration of the first lower claw-type elastic clamping parts 1-6 is the same as that of the first upper claw-type elastic clamping parts 1-1.

[0011] The central axis of the clamping curved surface of the first upper claw-type elastic clamping component 1-1 and the first lower claw-type elastic clamping component 1-6 forms a small angle of less than 12° with the central axis of the first upper hollow frame ring 1-2 and the first lower hollow frame ring 1-7 when the nuclear fuel rod 4 is not clamped. Assuming that the diameter of the nuclear fuel rod 4 to be installed is D, the diameter enclosed by the uppermost clamping points of the first upper claw-type elastic clamping component 1-1 and the first lower claw-type elastic clamping component 1-6 is D-0.5mm, and the diameter enclosed by the lowermost clamping points is D+0.18mm.

[0012] The inner diameters of the first upper hollow frame ring 1-2 and the first lower hollow frame ring 1-7 are the same, which is D+2.6mm, and the inner diameter of the first hollow guide ring 1-4 is D+1.1mm.

[0013] The first lower torsion stirring wing 1-5 guides part of the water flow to the inside of the first hollow guide ring 1-4 after being impacted by the coolant from below, and forms a transverse secondary flow at a certain speed under the action of the torsion structure; the first upper torsion stirring wing 1-3 receives the impact of the remaining coolant due to the 15° deflection angle with the first lower torsion stirring wing 1-5, and guides the water flow to the outside, participating in the agitation between other grid units, and forming a transverse secondary flow at a certain speed under the action of the torsion structure.

[0014] The edge grid unit 2 includes a second hollow guide ring 2-4 in the middle layer, and two second upper twisting and stirring wings 2-3 grow upward from its upper edge. The second upper twisting and stirring wings 2-3 gradually decrease in width upward and twist outward, and are finally connected to the second upper hollow frame ring 2-2 at the top. At the same time, the second hollow guide ring 2-4 and the second upper hollow frame ring 2-2 are assisted by the first upper special-shaped connecting component 2-8 in the direction close to the periphery, and four second upper claw-type elastic clamping components 2-1 are evenly distributed inside the second upper hollow frame ring 2-2; two second lower twisting and stirring wings 2-3 grow downward from the lower edge of the second hollow guide ring 2-4. The second lower twisting stirring wing 2-5 gradually decreases in width downward and twists outward, and is finally connected to the second lower hollow frame ring 2-7 at the bottom. At the same time, the first lower special-shaped connecting component 2-9 assists in connecting the second hollow guide ring 2-4 and the second lower hollow frame ring 2-7 in the direction close to the periphery. The arrangement position of the second lower twisting stirring wing 2-5 and the second upper twisting stirring wing 2-3 has an angle difference of 40°, and four second lower claw-type elastic clamping components 2-6 are evenly distributed inside the second lower hollow frame ring 2-7. The configuration of the second lower claw-type elastic clamping component 2-6 is the same as that of the second upper claw-type elastic clamping component 2-1.

[0015] The corner grid unit 3 includes a third hollow guide ring 3-4 in the middle layer, and two third upper twisting and stirring wings 3-3 grow upward from its upper edge. The width of the third upper twisting and stirring wings 3-3 gradually decreases upward and twists outward, and is finally connected to the top third upper hollow frame ring 3-2. At the same time, the third hollow guide ring 3-4 and the third upper hollow frame ring 3-2 are assisted by the second upper special-shaped connecting component 3-8 in the direction close to the periphery. Four third upper claw-type elastic clamping components 3-1 are evenly distributed inside the third upper hollow frame ring 3-2; growing downward from the lower edge of the third hollow guide ring 3-4 A third lower torsion stirring wing 3-5 is produced, the width of the third lower torsion stirring wing 3-5 gradually decreases downward and twists outward, and is finally connected to the third lower hollow frame ring 3-7 at the bottom. At the same time, the third hollow guide ring 3-4 and the third upper hollow frame ring 3-7 are assisted by the second lower special-shaped connecting component 3-9 in the direction close to the periphery; the arrangement position of the third lower torsion stirring wing 3-5 and the third upper torsion stirring wing 3-3 has an angle difference of 40°, and four third lower claw-type elastic clamping components 3-6 are evenly distributed inside the third lower hollow frame ring 3-7, and the configuration is the same as the third upper claw-type elastic clamping component 3-1.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] The present invention uses 3D printing technology in additive manufacturing technology to manufacture an integrated complex nuclear fuel assembly positioning grid structure, which reduces the manufacturing difficulty and time compared to the multi-process and multi-mold characteristics required by the traditional positioning grid manufacturing process; the open grid unit forms a directional guide channel to enhance the circulation capacity of the cooling medium around the nuclear fuel rod; the streamlined torsion stirring wing expands the fluid disturbance range while separately stirring the different flow domains between the nuclear fuel rod surface and the grid unit, thereby improving the coolant mixing performance; at the same time, the claw-type elastic clamping structure can not only realize positioning and clamping at the same time, but also provide auxiliary guiding function for the nuclear fuel rod during installation, and the clamping force can be directly modified by adjusting the inclination angle of the clamping structure to adapt to the actual working environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic diagram of the structure of an embodiment of the present invention.

[0019] Figure 2 2 is a top view of an embodiment of the present invention.

[0020] Figure 3 This is an axonometric view of the internal grid unit of an embodiment of the present invention.

[0021] Figure 4 2 is a top view of the internal grid unit according to an embodiment of the present invention.

[0022] Figure 5 This is an axonometric view of an edge grid unit according to an embodiment of the present invention.

[0023] Figure 6 FIG. 4 is a top view of an edge grid unit according to an embodiment of the present invention.

[0024] Figure 7 This is an axonometric view of an angle grid unit according to an embodiment of the present invention.

[0025] Figure 8 FIG. 2 is a top view of an angle grid unit according to an embodiment of the present invention. FIG. DETAILED DESCRIPTION

[0026] The present invention is described in detail below with reference to the accompanying drawings and embodiments so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby more clearly defining the protection scope of the present invention.

[0027] Reference Figure 1 and Figure 2 A double-layer scrambled wing nuclear fuel assembly positioning grid based on additive manufacturing includes internal grid units 1, edge grid units 2, and corner grid units 3. Taking a 5×5 grid as an example, nine internal grid units 1 are interconnected to form a 3×3 square array. Twelve edge grid units 2 extend along the four sides of the square array, surrounding the edges of the square array except the four corners. The edge grid units 2 at the end of each side are respectively connected to the corner grid units 3 to achieve edge and corner transitions. There are four edge grid units in total. The grid units are connected by partially overlapping boundaries to form an integrated positioning grid.

[0028] The inner cell frame 1, edge grid unit 2, and corner grid unit 3 respectively have two layers of eight, four, and three stirring wings;

[0029] The positioning grid is made of high-temperature alloy or zirconium alloy material and is formed from bottom to top using 3D printing technology. During assembly, 25 nuclear fuel rods 4 with a diameter of 9.5 mm and a ball end are inserted into the positioning grid from bottom to top. The clamping structure automatically positions and clamps, and water flows from bottom to top through two layers of twisted stirring wings to improve heat exchange efficiency.

[0030] Reference Figure 3 and Figure 4The internal grid unit 1 includes a first hollow guide ring 1-4 in the middle layer, from which four first upper twisting and stirring wings 1-3 extend upward. These wings gradually decrease in width and twist outward, ultimately connecting to the topmost first upper hollow frame ring 1-2. Four first upper claw-type elastic clamping members 1-1 are evenly distributed within the first upper hollow frame ring 1-2. Four first lower twisting and stirring wings 1-5 extend downward from the bottom edge of the first hollow guide ring 1-4. These wings gradually decrease in width and twist outward, ultimately connecting to the bottommost first lower hollow frame ring 1-7. The first lower twisting and stirring wings 1-5 are arranged at a 15° angle to the first upper twisting and stirring wings 1-3. Four first lower claw-type elastic clamping members 1-6 are evenly distributed within the first lower hollow frame ring 1-7, with the same configuration as the first upper claw-type elastic clamping members 1-1.

[0031] In this embodiment, the central axis of the clamping curved surface of the first upper claw type elastic clamping component 1-1 and the first lower claw type elastic clamping component 1-6 forms a small angle of 8° with the central axis of the first upper hollow frame ring 1-2 and the first lower hollow frame ring 1-7 when the nuclear fuel rod 4 is not clamped. In this embodiment, the diameter of the nuclear fuel rod 4 to be installed is 9.5mm. The diameter enclosed by the uppermost clamping points of the first upper claw type elastic clamping component 1-1 and the first lower claw type elastic clamping component 1-6 is 9mm, and the diameter enclosed by the lowermost clamping points is 9.68mm. The larger diameter at the bottom facilitates the accommodation of the nuclear fuel rod 4 into the first upper claw type elastic clamping component 1-1 and the first lower claw type elastic clamping component 1-6, providing an auxiliary guiding function for the installation of the nuclear fuel rod 4, and the cylindrical clamping surface provides a positioning function. After positioning, the elastic force generated by the structural deformation provides a clamping force for clamping.

[0032] The thickness, height and inner diameter of the first upper hollow frame ring 1-2 and the first lower hollow frame ring 1-7 are the same, which are 0.5mm, 5mm and 12.1mm respectively, and the total height of the grid is 35mm; the inner diameter of the first hollow guide ring 1-4 is 10.6mm, and the distance between the first upper hollow frame ring 1-2 and the first hollow guide ring 1-4 is 10mm, which is the same as the distance between the first lower hollow frame ring 1-7 and the first hollow guide ring 1-4.

[0033] After being impacted by the coolant from below, the first lower torsion slurry wings 1-5 guide some of the water flow toward the interior of the first hollow guide ring 1-4, and under the action of the torsion structure, a transverse secondary flow at a certain speed is formed. Since the first upper torsion slurry wings 1-3 are deflected at a 15° angle relative to the first lower torsion slurry wings 1-5, they can receive the remaining coolant impact and guide the water flow toward the outside, participating in the turbulence between other grid units, and under the action of the torsion structure, a transverse secondary flow at a certain speed is formed. In this embodiment, the first upper torsion slurry wings 1-3 and the first lower torsion slurry wings 1-5 are both 0.5 mm thick and have a torsion angle of 65°.

[0034] Reference Figure 5 and Figure 6 The edge grid unit 2 includes a second hollow guide ring 2-4 in the middle layer, and two second upper twisting and stirring wings 2-3 grow upward from its upper edge. The second upper twisting and stirring wings 2-3 gradually decrease in width upward and twist outward, and are finally connected to the top second upper hollow frame ring 2-2. At the same time, the second hollow guide ring 2-4 and the second upper hollow frame ring 2-2 are assisted by the first upper special-shaped connecting component 2-8 in the direction close to the periphery. Four second upper claw-type elastic clamping components 2-1 are evenly distributed inside the second upper hollow frame ring 2-2; growing downward from the lower edge of the second hollow guide ring 2-4 Two second lower torsion stirring wings 2-5 are grown, the width of the second lower torsion stirring wings 2-5 gradually decreases downward and twists outward, and finally connects with the second lower hollow frame ring 2-7 at the bottom. At the same time, the first lower special-shaped connecting component 2-9 assists in connecting the second hollow guide ring 2-4 and the second upper hollow frame ring 2-7 in the direction close to the periphery; the arrangement position of the second lower torsion stirring wings 2-5 and the second upper torsion stirring wings 2-3 has an angle difference of 40°, and four second lower claw-type elastic clamping components 2-6 are evenly distributed inside the second lower hollow frame ring 2-7, and the configuration is the same as the second upper claw-type elastic clamping component 2-1.

[0035] Reference Figure 7 and Figure 8The corner grid unit 3 includes a third hollow guide ring 3-4 in the middle layer, and two third upper twisting and stirring wings 3-3 grow upward from its upper edge. The width of the third upper twisting and stirring wings 3-3 gradually decreases upward and twists outward, and is finally connected to the top third upper hollow frame ring 3-2. At the same time, the third hollow guide ring 3-4 and the third upper hollow frame ring 3-2 are assisted by the second upper special-shaped connecting component 3-8 in the direction close to the periphery. Four third upper claw-type elastic clamping components 3-1 are evenly distributed inside the third upper hollow frame ring 3-2; growing downward from the lower edge of the third hollow guide ring 3-4 A third lower torsion stirring wing 3-5 is formed, the width of the third lower torsion stirring wing 3-5 gradually decreases downward and twists outward, and is finally connected to the third lower hollow frame ring 3-7 at the bottom. At the same time, the third hollow guide ring 3-4 and the third upper hollow frame ring 3-7 are assisted by the second lower special-shaped connecting component 3-9 in the direction close to the periphery. The arrangement position of the third lower torsion stirring wing 3-5 and the third upper torsion stirring wing 3-3 has an angle difference of 40°, and four third lower claw-type elastic clamping components 3-6 are evenly distributed inside the third lower hollow frame ring 3-7, and the configuration is the same as the third upper claw-type elastic clamping component 3-1.

[0036] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention's description and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A double-layer slurry wing nuclear fuel assembly positioning grid based on additive manufacturing, characterized by: The invention comprises an internal grid unit (1), an edge grid unit (2) and a corner grid unit (3); wherein the internal grid units (1) are connected to each other to form a square matrix; the edge grid units (2) are arranged along the four sides of the square matrix, surrounding the edges of the square matrix excluding the four corners; the edge grid units (2) at the end of each side are respectively connected to the corner grid units (3) to achieve edge and corner transition; the grid units are connected by partially overlapping boundaries; The inner cell frame (1), edge grid unit (2), and corner grid unit (3) respectively have two layers of eight, four, and three stirring wings; The positioning grid is integrally formed from bottom to top by metal 3D printing, and the material is zirconium alloy or high-temperature alloy.

2. The double-layer slurry wing nuclear fuel assembly positioning grid according to claim 1, characterized in that: The internal grid unit (1) comprises a first hollow guide ring (1-4) in the middle layer, and four first upper twisting and stirring wings (1-3) grow upward from the upper edge of the first hollow guide ring. The first upper twisting and stirring wings (1-3) gradually decrease in width upward and twist outward, and are finally connected to the top first upper hollow frame ring (1-2). Four first upper claw-shaped elastic clamping parts (1-1) are evenly distributed inside the first upper hollow frame ring (1-2); four first lower twisting and stirring wings grow downward from the lower edge of the first hollow guide ring (1-4). The stirring wing (1-5) is provided with a first lower twisting stirring wing (1-5), the width of which gradually decreases downward and twists outward, and is finally connected to the first lower hollow frame ring (1-7) at the bottom. The arrangement positions of the first lower twisting stirring wing (1-5) and the first upper twisting stirring wing (1-3) have an angle difference of 15 degrees. Four first lower claw-type elastic clamping parts (1-6) are evenly distributed inside the first lower hollow frame ring (1-7). The configuration of the first lower claw-type elastic clamping parts (1-6) is the same as that of the first upper claw-type elastic clamping part (1-1).

3. The double-layer slurry wing nuclear fuel assembly spacer according to claim 2, characterized in that: When no nuclear fuel rod (4) is clamped, the central axis of the clamping curved surface of the first upper claw-type elastic clamping component (1-1) and the first lower claw-type elastic clamping component (1-6) forms a small angle of less than 12° with the central axis of the first upper hollow frame ring (1-2) and the first lower hollow frame ring (1-7). Assuming that the diameter of the nuclear fuel rod (4) to be installed is D, the diameter enclosed by the uppermost clamping points of the first upper claw-type elastic clamping component (1-1) and the first lower claw-type elastic clamping component (1-6) is D-0.5mm, and the diameter enclosed by the lowermost clamping points is D+0.18mm.

4. The double-layer slurry wing nuclear fuel assembly spacer grid according to claim 2, characterized in that: The inner diameters of the first upper hollow frame ring (1-2) and the first lower hollow frame ring (1-7) are the same, namely D+2.6 mm, and the inner diameter of the first hollow guide ring (1-4) is D+1.1 mm.

5. The double-layer slurry wing nuclear fuel assembly spacer grid according to claim 2, characterized in that: The first lower twisting turbulence wing (1-5) guides part of the water flow to the inside of the first hollow guide ring (1-4) after being impacted by the coolant from below, and forms a transverse secondary flow with a certain speed under the action of the twisting structure; the first upper twisting turbulence wing (1-3) receives the impact of the remaining coolant due to a 15° deflection angle with the first lower twisting turbulence wing (1-5), and guides the water flow to the outside, participating in the turbulence between other grid units, and forming a transverse secondary flow with a certain speed under the action of the twisting structure.

6. The double-layer slurry wing nuclear fuel assembly spacer grid according to claim 1, characterized in that: The edge grid unit (2) comprises a second hollow guide ring (2-4) in the middle layer, and two second upper twisting and stirring wings (2-3) grow upward from the upper edge of the second upper twisting and stirring wings (2-3), the width of the second upper twisting and stirring wings (2-3) gradually decreases upward and twists outward, and is finally connected to the second upper hollow frame ring (2-2) at the top, and at the same time, the second hollow guide ring (2-4) and the second upper hollow frame ring (2-2) are assisted by the first upper special-shaped connecting component (2-8) in the direction close to the periphery, and four second upper claw-shaped elastic clamping components (2-1) are evenly distributed inside the second upper hollow frame ring (2-2); two second lower twisting and stirring wings grow downward from the lower edge of the second hollow guide ring (2-4) The stirring wing (2-5) is provided with a second lower twisting stirring wing (2-5), the width of which gradually decreases downward and twists outward, and is finally connected to the second lower hollow frame ring (2-7) at the bottom. At the same time, the second hollow guide ring (2-4) and the second lower hollow frame ring (2-7) are assisted by the first lower special-shaped connecting component (2-9) in the direction close to the periphery. The arrangement position of the second lower twisting stirring wing (2-5) and the second upper twisting stirring wing (2-3) has an angle difference of 40 degrees. Four second lower claw-type elastic clamping components (2-6) are evenly distributed inside the second lower hollow frame ring (2-7). The configuration of the second lower claw-type elastic clamping components (2-6) is the same as that of the second upper claw-type elastic clamping components (2-1).

7. The double-layer slurry fin nuclear fuel assembly spacer grid according to claim 1, characterized in that: The corner grid unit (3) includes a third hollow guide ring (3-4) in the middle layer, and two third upper twisting and stirring wings (3-3) grow upward from the upper edge of the third upper twisting and stirring wings (3-3). The width of the third upper twisting and stirring wings (3-3) gradually decreases upward and twists outward, and is finally connected to the third upper hollow frame ring (3-2) at the top. At the same time, the third hollow guide ring (3-4) and the third upper hollow frame ring (3-2) are assisted by a second upper special-shaped connecting component (3-8) in the direction close to the periphery. Four third upper claw-shaped elastic clamping components (3-1) are evenly distributed inside the third upper hollow frame ring (3-2); growing downward from the lower edge of the third hollow guide ring (3-4), the third upper twisting and stirring wings (3-3) are connected to the third upper hollow frame ring (3-2). A third lower twisting and stirring wing (3-5) is formed, the width of the third lower twisting and stirring wing (3-5) gradually decreases downward and twists outward, and is finally connected to the third lower hollow frame ring (3-7) at the bottom. At the same time, the third hollow guide ring (3-4) and the third upper hollow frame ring (3-7) are assisted by a second lower special-shaped connecting component (3-9) in the direction close to the periphery. The arrangement positions of the third lower twisting and stirring wing (3-5) and the third upper twisting and stirring wing (3-3) have an angle difference of 40 degrees. Four third lower claw-type elastic clamping components (3-6) are evenly distributed inside the third lower hollow frame ring (3-7), and the configuration is the same as that of the third upper claw-type elastic clamping component (3-1).

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