Low-wind-pressure ice and snow-resistant overhead conductor and stranding tool

Abstract

The invention relates to a low-wind-pressure ice and snow-resistant overhead conductor and a twisting tool. The overhead conductor comprises a bearing core, an inner conductor layer and an outer conductor layer, the inner conductor layer wraps the bearing core, and a gap is formed between the inner conductor layer and the bearing core and is filled with filler; the inner conductor layer is coated with the outer conductor layer, the outer side surface of the outer conductor layer is composed of a plurality of arc surfaces which are arranged in an annular array and are sequentially connected end to end, a blade point is formed between every two adjacent arc surfaces, and mastoid structures are processed on all the arc surfaces; according to the wire structure, the gap is arranged between the bearing core and the inner conductor layer and is filled with the filler to form a self-damping structure, so that the effect of reducing aeolian vibration can be achieved; and a unique outer conductor layer structure is arranged, and the cutting and airflow guiding effects can be achieved through a blade structure on the outer conductor layer structure, so that the wind pressure on the surface of the wire is effectively reduced, the possibility of wire breakage of the wire is reduced, and stable operation of a circuit is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of cables, in particular to a low wind pressure type ice and snow resistant overhead conductor and a twisting tool. Background Art

[0002] Daily life and industrial development are inseparable from the availability of sufficient electricity. my country, despite its vast territory, boasts a complex terrain dominated by plateaus, mountains, and hills, and an extremely complex and changeable climate. In certain regions, severe weather conditions such as strong winds, rain, and snow may coexist. Overhead transmission lines, as a crucial component of the power system, are susceptible to failures due to their structural and operational characteristics.

[0003] When existing overhead wires are used in strong winds and rainy and snowy environments, they are prone to wire breakage or strand breakage due to excessive wind pressure on the wire surface or vibration due to breeze. In addition, in low temperature environments such as rain and snow, the wire surface is easily covered with ice, which will further affect the safety and stable operation of the line. Summary of the Invention

[0004] To this end, the technical problem to be solved by the present invention is to overcome the problem in the prior art that when overhead wires are used in strong winds and rain and snow environments, they are prone to wire breakage or strand breakage due to excessive wind pressure on the wire surface or vibration due to breeze, and in low temperature environments such as rain and snow, the wire surface is easily covered with ice, which will further affect the safety and stable operation of the line.

[0005] In order to solve the above technical problems, the present invention provides a low wind pressure type ice and snow resistant overhead conductor, comprising: load-bearing core; An inner conductor layer, the inner conductor layer is coated on the outside of the load-bearing core, and a gap is formed between the inner conductor layer and the load-bearing core; a filler, the filler filling the gap; The outer conductor layer is coated on the outside of the inner conductor layer. The side of the outer conductor layer away from the inner conductor layer is composed of a plurality of circular arc surfaces arranged in a ring array and connected end to end in sequence. A blade is formed between two adjacent circular arc surfaces, and each of the circular arc surfaces is processed with a plurality of nipple structures.

[0006] Preferably, the inner conductor layer is provided with at least one layer, and the inner conductor layer includes a plurality of inner conductors twisted outside the load-bearing core, and the inner conductors all adopt a profile with a trapezoidal cross section.

[0007] Preferably, the outer conductor layer comprises first outer conductors and second outer conductors, a plurality of the first outer conductors are twisted outside the inner conductor layer, and a second outer conductor is twisted between two adjacent first outer conductors, the first outer conductor comprises two first arc-shaped surfaces which are symmetrical to each other, and the two first arc-shaped surfaces are connected at one end to form the blade, and the second outer conductor comprises a second arc-shaped surface, and the two first arc-shaped surfaces of the two adjacent first outer conductors and the second arc-shaped surface between them form an arc surface.

[0008] Preferably, a plurality of the papillae structures are formed on the first arc-shaped surface and the second arc-shaped surface, respectively.

[0009] Preferably, the inner conductor, the first outer conductor and the second outer conductor are made of heat-resistant aluminum alloy.

[0010] Preferably, the force-bearing core comprises a stainless steel light unit, and a plurality of extra-strong steel core wires or a hollow carbon fiber rod are twisted outside the stainless steel light unit.

[0011] Preferably, the filler is made of anti-corrosion grease.

[0012] A twisting tool for twisting the low-wind-pressure anti-ice and snow overhead conductor as described in any one of the above embodiments comprises, A wire distribution plate, which is a circular plate, and a plurality of wire passing grooves are arranged in a circular array on the side surface of the wire distribution plate; A plurality of pressing devices are provided, each of which comprises a mounting plate, a limiting wheel, an extension driving source and a pressing die, each of the mounting plates is vertically connected to the same surface of the wire distribution plate and is located on one side of one of the wire passing grooves, each of the mounting plates is rotatably connected with one of the limiting wheels, the position of the limiting wheel close to the wire passing groove corresponds to the position of the wire passing groove, a circular groove is coaxially arranged on the circumferential surface of the limiting wheel, and at least one of the extension driving sources is arranged on each of the mounting plates, and the output end of the extension driving source faces the circular groove and is provided with the pressing die.

[0013] Preferably, the cross section of the circular groove is trapezoidal, and a rubber layer is arranged on the inner wall of the circular groove.

[0014] Preferably, the pressing die comprises a first pressing die and a second pressing die, the first pressing die comprises a first pressing die surface in the shape of a circular arc, and the second pressing die comprises a second pressing die surface corresponding to the shape of the blade.

[0015] The above technical solution of the present application has the following beneficial effects compared with the prior art: The low-wind-pressure anti-ice-and-snow overhead conductor and stranding tool provided by the application comprises a force-bearing core, an inner conductor layer and an outer conductor layer; the inner conductor layer is wrapped around the force-bearing core and has a gap between the force-bearing core and the inner conductor layer, and the gap is filled with a filler; the outer conductor layer is wrapped around the inner conductor layer, and the side of the outer conductor layer away from the inner conductor layer is composed of a plurality of circular arc surfaces arranged in an annular array and connected end to end in sequence, a knife edge is formed between two adjacent circular arc surfaces, and each circular arc surface is provided with a papilla structure; the self-damping structure formed by the gap between the force-bearing core and the inner conductor layer and the filler can reduce the wind vibration, and the fatigue wire breakage of the conductor can be avoided; the unique structure of the outer conductor layer can "cut" the airflow through the knife edge structure and guide the airflow through the circular arc surface, so that the wind pressure on the surface of the conductor is effectively reduced, and the possibility of wire breakage in a strong wind environment is reduced; and the papilla structure arranged on the outer surface of the conductor can form a "lotus effect" on the outer surface of the conductor, so that the conductor has high hydrophobicity, rainwater can be prevented from gathering and icing on the surface of the conductor, and the stable operation of the line can be ensured. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to make the content of the application more easily understood, the application will be further described in detail below according to specific embodiments of the application and in conjunction with the drawings, in which Figure 1 is a schematic diagram of the low-wind-pressure anti-ice-and-snow overhead conductor cutting airflow of the application; Figure 2 is a schematic diagram of the overall structure of the low-wind-pressure anti-ice-and-snow overhead conductor of the application; Figure 3 is a schematic diagram of the first structure form of the force-bearing core of the low-wind-pressure anti-ice-and-snow overhead conductor of the application; Figure 4 is a schematic diagram of the second structure form of the force-bearing core of the low-wind-pressure anti-ice-and-snow overhead conductor of the application; Figure 5 is a structural schematic diagram of the inner conductor of the low-wind-pressure anti-ice-and-snow overhead conductor of the application; Figure 6 is a structural schematic diagram of the first outer conductor of the low-wind-pressure anti-ice-and-snow overhead conductor of the application; Figure 7 is a structural schematic diagram of the second outer conductor of the low-wind-pressure anti-ice-and-snow overhead conductor of the application; Figure 8 is a structural schematic diagram of the split plate of the stranding tool of Example 2; Figure 9 is a structural schematic diagram of the pressing device of the stranding tool of Example 2; Figure 10 is a structural schematic diagram of the limiting wheel of the stranding tool of Example 2; Figure 11 is a schematic view of a first structural form of the compression cover mold of the twisting tool of Example Two (wherein a is an elevation view, b is a right side view, and c is a plan view); Figure 12 is a schematic view of a second structural form of the compression cover mold of the twisting tool of Example Two (wherein a is an elevation view, b is a right side view, and c is a plan view); Figure 13 is a structural schematic view of the special-shaped compression mold of Example Three.

[0017] Description of the Drawings: 1, load-carrying core; 11, stainless steel light unit; 12, extra-strong steel core wire; 13, hollow carbon fiber rod; 2, inner conductor layer; 21, inner conductor; 3, filler; 4, outer conductor layer; 41, circular arc surface; 42, knife edge; 43, first outer conductor; 431, first arc surface; 44, second outer conductor; 441, second arc surface; 5, wire distribution plate; 51, wire passage; 6, compression device; 61, mounting plate; 62, limiting wheel; 621, annular groove; 622, rubber layer; 63, telescopic drive source; 631, air supply device; 632, nylon thimble; 633, cylinder; 634, air supply pipe; 64, compression cover mold; 641, first compression cover mold; 642, second compression cover mold; 7, mold body; 71, mold hole. DETAILED DESCRIPTION

[0018] The present application will be further described below in conjunction with the drawings and specific examples, so that those skilled in the art can better understand the present application and implement it, but the examples are not limiting to the present application.

[0019] Example One: Referring to Figures 1-7 the drawings, a low-wind-pressure anti-ice-and-snow overhead conductor of the present application comprises, a load-carrying core 1; an inner conductor layer 2, the inner conductor layer 2 being wrapped around the load-carrying core 1, and having a gap between the load-carrying core 1 and the inner conductor layer 2; a filler 3, the filler 3 being filled in the gap; an outer conductor layer 4, the outer conductor layer 4 being wrapped around the inner conductor layer 2, and the side of the outer conductor layer 4 away from the inner conductor layer 2 being composed of a plurality of circular arc surfaces 41 arranged in an annular array and connected end to end in sequence, a knife edge 42 being formed between each two adjacent circular arc surfaces 41, and each circular arc surface 41 being provided with a plurality of papillary structures.

[0020] Specifically, in the process of normal operation, the heat-resistant aluminum alloy wire composed of the inner conductor layer 2 and the outer conductor layer 4 is in a permanent elongation state and is basically not subjected to force, and the mechanical load can be considered to be entirely borne by the load-carrying core 1, so that the overhead conductor has the characteristics of low sag after the motion temperature is higher than the inflection point temperature. The load-carrying core 1 of the overhead conductor adopts the structure of a hollow carbon fiber rod 13 internally provided with a stainless steel light unit 11 or a stainless steel light unit 11 externally twisted with a super-strong steel core wire 12, has higher tensile strength and fatigue resistance, and has lighter weight, which is conducive to reducing the sag of the conductor and allowing the use of a larger cross-section of the conductor, thereby reducing the resistance and line loss of the conductor and increasing the load-carrying capacity. At the same time, the span can be increased under the same sag, the number of towers can be reduced, and the mechanical load of the tower and the foundation can be reduced, thereby reducing the cost of the tower.

[0021] Specifically, the load-carrying core 1 and the inner conductor layer 2 of the overhead conductor have a gap therebetween, the gap thickness is controlled to be between 0.5mm and 0.7mm on a single side, and a filler 3 is filled in the gap to form a self-damping structure; the vibration frequency of the load-carrying core 1 and the outer conductor structure is different, so that a part of the energy can be dissipated, thereby reducing the wind-induced vibration and avoiding the occurrence of conductor fatigue and broken strands.

[0022] Specifically, the cross section of the outer conductor layer 4 is in the shape of a polygon such as a regular hexagon, and each side is a circular arc line. Such a shape makes the outer side of the outer conductor layer 4 have a plurality of blade structures 42, which can cut the airflow and guide the airflow through the circular arc surface 41, thereby effectively reducing the wind pressure on the surface of the conductor (acting as a wind pressure relief), reducing the possibility of conductor breakage and strand breakage in a strong wind environment, and ensuring stable operation of the line.

[0023] Specifically, a plurality of nano-scale papillary structures in the shape of small mountains are cut on the outer surface of the outer conductor layer 4 by laser cutting. These papillary structures can make the outer surface of the conductor have super-hydrophobicity, thereby avoiding the accumulation of rainwater on the surface of the conductor and the occurrence of icing phenomenon, and ensuring the safety of the line.

[0024] Further, the inner conductor layer 2 is provided with at least one layer, the inner conductor layer 2 comprises a plurality of inner conductors 21 twisted outside the load-bearing core 1, and the inner conductors 21 all adopt a trapezoidal profile. Specifically, the inner conductors 21 are designed as trapezoids, which can form a relatively stable inner arch structure, and are beneficial to the stability of the overall structure of the conductor. Specifically, the number of conductor layers is 2-3 layers, the number of inner layer profiles is 6-10, and the number of outer layer profiles is 10-18. The final number is comprehensively considered according to the height H and width L of the profile. If the height H of the profile is too high, the profile is prone to turning over during twisting. If the width L is too large, it will rub against the equipment during twisting, causing damage to the appearance of the conductor. According to experience, the ratio of the width to the height of the profile (L / H) should be controlled within the range of 1.3-1.8. The profile single line chamfer R is designed to be between 0.5-0.8, because the profile single line will lose about 5% during tensioning and twisting, and the design area of the profile single line should be about 1.1 times the nominal area of the twisted single line. Specifically, the compression coefficients of the inner conductor layer 2 and the outer conductor layer 4 are basically the same, and are controlled between 88% and 93%, so that the conductor can be tightly compressed and not excessively compressed, and the compression coefficients of the inner and outer layers are kept the same, which can also avoid the snake shape of the conductor.

[0025] Further, the outer conductor layer 4 comprises a first outer conductor 43 and a second outer conductor 44, a plurality of first outer conductors 43 are twisted outside the inner conductor layer 2, and a second outer conductor 44 is twisted between any two adjacent first outer conductors 43. The first outer conductor 43 comprises two first arc surfaces 431 which are symmetrical to each other and connected at one end to form a blade 42. The second outer conductor 44 comprises a second arc surface 441. The two first arc surfaces 431 of the adjacent two first outer conductors 43 and the second arc surface 441 located therebetween form a circular arc surface 41. Specifically, the outer conductor layer 4 is composed of two different structures of special-shaped wires, and in this embodiment, six first outer conductors 43 and six second outer conductors 44 are twisted together, wherein the second outer conductor 44 is located between the adjacent two first outer conductors 43. In this embodiment, the cross section of the first outer conductor 43 is in the shape of a regular pentagon, two sides of which are arc sides and the two first arc surfaces 431 corresponding to the arc sides form the blade 42. The cross section of the second outer conductor 44 is in the shape of a trapezoid, the upper base and the lower base of which are arc lines, and the second arc surface 441 corresponding to the lower base and the two first arc surfaces 431 of the adjacent two first outer conductors 43 form a complete circular arc surface 41.

[0026] Further, the first arc surface 431 and the second arc surface 441 are respectively provided with a plurality of papillary structures. Specifically, the papillary structures are convex protrusions in the shape of small hills. The papillary structures arranged on the outer surface of the conductor can form a "lotus leaf effect" on the outer surface of the conductor, so that the conductor has high hydrophobicity and rainwater is prevented from gathering and icing on the surface of the conductor.

[0027] Further, the inner conductor 21, the first outer conductor 43 and the second outer conductor 44 are all made of heat-resistant aluminum alloy material. The conductive material used in the conductor is heat-resistant aluminum alloy material, specifically 61.8% IACS super heat-resistant aluminum alloy material (continuous allowable operating temperature 210℃) or high-strength heat-resistant aluminum alloy material (continuous allowable operating temperature 150℃). The loadable temperature is much higher than that of ordinary aluminum and high-strength aluminum alloy material, so the unit length mass of the conductor is lower than that of the conductor with the same transmission capacity, the tower burden is small, the safety is higher, the transmission capacity is higher than that of the conductor with the same weight, and the current carrying capacity is stronger.

[0028] Further, the load-bearing core 1 comprises a stainless steel optical unit 11, a plurality of super strong steel core wires 12 are stranded outside the stainless steel optical unit 11 or a hollow carbon fiber rod 13 is sleeved. The stainless steel optical unit 11 comprises a stainless steel pipe and a plurality of optical fibers arranged in the stainless steel pipe, and the stainless steel pipe is filled with fiber paste. By arranging the stainless steel optical unit 11, the conductor can have communication function.

[0029] Further, the filler 3 is made of anti-corrosion grease. The anti-corrosion grease can play the roles of waterproofing, moisture-proofing and air isolation, so as to prevent the internal structure of the conductor from being corroded. In addition, the anti-corrosion grease can play the roles of buffering and lubrication, so as to reduce the friction between the load-bearing core 1 and the external conductor structure, which is beneficial to prolong the service life of the conductor.

[0030] Embodiment two: with reference to Figures 8-12 As shown in the drawings, the application further discloses a stranding tool for stranding the low-wind-pressure anti-ice-and-snow overhead conductor of embodiment one, which comprises, The distribution plate 5 is a circular plate, and a plurality of wire passing grooves 51 are arranged in a circular array around the circumference of the distribution plate 5; The pressing device 6 is provided with a plurality of groups, and each group of the pressing device 6 comprises a mounting plate 61, a limiting wheel 62, an extension drive source 63 and a pressing cover 64. Each mounting plate 61 is vertically connected to the same face of the distribution plate 5 and is located on one side of one wire passing groove 51. One limiting wheel 62 is rotatably connected to each mounting plate 61, and the position of the limiting wheel 62 corresponds to the position of the wire passing groove 51 close to the mounting plate 61. A circular groove 621 is coaxially arranged on the circumferential surface of the limiting wheel 62. At least one extension drive source 63 is arranged on each mounting plate 61, and the output end of the extension drive source 63 faces the circular groove 621 and is provided with the pressing cover 64.

[0031] Specifically, due to the special shape of the wire body constituting the inner conductor layer 2 and the outer conductor layer 4, when the single wire turns over or deviates due to uneven force during the twisting process of the conductor, the normal twisting or the twisting compression force will be affected, which will affect the consistency of the product. The present embodiment provides a twisting tool that can ensure that each wire body can be twisted in a predetermined pose.

[0032] Specifically, the wire distribution plate 5 is used for wire distribution. When the wire body is twisted, each wire body passes through a wire slot 51 on the wire distribution plate 5 and then passes through the annular slot 621 of the limiting wheel 62. The output shaft of the telescopic drive source 63 arranged on one side of the limiting wheel 62 is elongated, and the wire body is limited between the pressing cover mold 64 and the annular slot 621 by the pressing cover mold 64 connected to the output shaft of the telescopic drive source 63 corresponding to the shape of the wire body, so as to avoid the wire body from turning over or deviating during the twisting process. The telescopic drive source 63 can be a pneumatic cylinder.

[0033] The present embodiment provides a structure of a telescopic drive source, which includes a gas supply device 631, a nylon thimble 632, and a cylinder body 633. The cylinder body 633 is connected to the mounting plate 61, and the cylinder body 633 includes an internal cavity. Two through holes are respectively arranged at both ends of the cylinder body 633 and communicate with the cavity. One of the through holes is connected to the output end of the gas supply device 631 through a gas supply pipe 634, and the other through hole is slidably provided with the nylon thimble 632 (one end of the nylon thimble 632 in the cavity can be connected to a piston). One end of the nylon thimble 632 outside the cavity is connected to the pressing cover mold 64.

[0034] Further, the cross section of the annular slot 621 is trapezoidal, and a rubber layer 622 is arranged on the inner wall of the annular slot 621. Further, the pressing cover mold 64 is also coated with a rubber layer, which can protect the wire body and avoid damage to the wire body during the twisting process.

[0035] Further, the pressing cover mold 64 includes a first pressing cover mold 641 and a second pressing cover mold 642. The first pressing cover mold 641 includes a first pressing cover surface in the shape of a circular arc, and the second pressing cover mold 642 includes a second pressing cover surface corresponding to the shape of the blade 42.

[0036] Embodiment three: refer to Figure 13As shown, on the basis of Embodiment Two, the application further provides a special-shaped compacting die, which comprises a die body 7, and a die hole 71 matching the outer shape of the target wire is coaxially arranged on the die body 7, through which the outer conductor of the wire can be efficiently compacted, and the filling rate and geometric precision can be improved. Specifically, the cross-sectional shape of the die hole 71 matches the outer shape of the target wire, the inner wall of the die hole is coated with a nano coating after being polished or chrome-plated to reduce friction; and the input end of the die hole 71 has a certain taper, thereby facilitating the smooth entry of the stranded single wire into the die hole 71, the hole diameter of the middle section of the die hole 71 gradually shrinks, and the plastic deformation of the single wire is realized through the shrinkage of the cross section and the close fit; the end of the die hole is an equal cross-section section, which plays a role in stabilizing the final shape of the wire. Further, the cross section of the die hole 71 is reduced in equal ratio according to the design size of the wire (reduction rate 1.05-1.1 times), which compensates for the rebound effect. The length of the compacting section (the middle section of the die hole 71) is 4:1-6:1 compared with the diameter of the single wire, which ensures sufficient deformation without damaging the wire. More preferably, the die body 7 can be provided with a detachable die core structure, thereby adapting to various special-shaped wire specifications and improving the versatility of the compacting die, thereby reducing the cost of design and production.

[0037] Obviously, the above embodiments are only examples for clearly illustrating the application, and are not intended to limit the embodiments. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. Here, all the embodiments cannot be exhausted, and the obvious changes or variations derived therefrom are still within the protection scope of the application.

Claims

1. A low wind pressure type ice and snow resistant overhead conductor, characterized by: include, load-bearing core; An inner conductor layer, the inner conductor layer is coated on the outside of the load-bearing core, and a gap is formed between the inner conductor layer and the load-bearing core; a filler, the filler filling the gap; The outer conductor layer is coated on the outside of the inner conductor layer. The side of the outer conductor layer away from the inner conductor layer is composed of a plurality of circular arc surfaces arranged in a ring array and connected end to end in sequence. A blade is formed between two adjacent circular arc surfaces, and each of the circular arc surfaces is processed with a plurality of nipple structures.

2. The low wind pressure type ice and snow resistant overhead conductor according to claim 1, characterized in that: The inner conductor layer is provided with at least one layer, and the inner conductor layer includes a plurality of inner conductors twisted outside the load-bearing core, and the inner conductors all adopt a profile with a trapezoidal cross section.

3. The low wind pressure type ice and snow resistant overhead conductor according to claim 2, characterized in that: The outer conductor layer includes a first outer conductor and a second outer conductor. Several first outer conductors are twisted outside the inner conductor layer, and one second outer conductor is twisted between two adjacent first outer conductors. The first outer conductor includes two mutually symmetrical first arcuate surfaces, one end of the two first arcuate surfaces are connected to each other to form the blade. The second outer conductor includes a second arcuate surface. The two first arcuate surfaces of two adjacent first outer conductors that are close to each other and the second arcuate surface located between the two form the circular arc surface.

4. The low wind pressure type ice and snow resistant overhead conductor according to claim 3, characterized in that: A plurality of mastoid structures are processed on the first curved surface and the second curved surface respectively.

5. The low wind pressure type ice and snow resistant overhead conductor according to claim 3, characterized in that: The inner conductor, the first outer conductor and the second outer conductor are all made of heat-resistant aluminum alloy.

6. The low wind pressure type ice and snow resistant overhead conductor according to claim 1, characterized in that: The load-bearing core comprises a stainless steel optical unit, and a plurality of extra-strong steel core wires are twisted outside the stainless steel optical unit or a hollow carbon fiber rod is sheathed therein.

7. The low wind pressure type ice and snow resistant overhead conductor according to claim 1, characterized in that: The filler is antiseptic grease.

8. A twisting tool for twisting the low wind pressure type ice and snow resistant overhead conductor according to any one of claims 1 to 7, characterized in that: include, A line distribution plate, the line distribution plate is a circular plate, and a plurality of line passing grooves arranged in a circular array around the circumference of the line distribution plate are opened on the side surface of the line distribution plate; A clamping device, wherein the clamping device is provided with multiple groups, and the multiple groups of the clamping devices each include a mounting plate, a limiting wheel, a telescopic drive source and a pressing mold, and each of the mounting plates is vertically connected to the same surface of the branch plate and is respectively located on one side of the wire passing groove, and each of the mounting plates is rotatably connected to a limiting wheel, and the limiting wheel corresponds to the position of the wire passing groove close to the mounting plate, and an annular groove is coaxially opened on the circumferential surface of the limiting wheel, and each of the mounting plates is provided with at least one telescopic drive source, and the output end of the telescopic drive source faces the annular groove and is installed with the pressing mold.

9. The twisting tool according to claim 8, characterized in that: The cross section of the annular groove is trapezoidal, and a rubber layer is provided on the inner wall of the annular groove.

10. The twisting tool according to claim 8, characterized in that: The pressing mold includes a first pressing mold and a second pressing mold. The first pressing mold includes a first pressing surface in an arc shape, and the second pressing mold includes a second pressing surface corresponding to the shape of the blade.

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