Wire threading aid and method of threading

Abstract

The present application relates to the technical field of coal mine maintenance and discloses a threading auxiliary device and a threading method, the device comprising a protective tube, a connecting part and a heating part. The protective tube is spiral-shaped and made of a heat-expandable material, and an axial channel is formed inside the protective tube. The connecting part comprises a connecting ring and a traction line, the connecting ring being connected to one end of the protective tube, and the traction line being connected to the connecting ring for pulling the protective tube to move. The heating part comprises a heating wire, the heating wire passing through the axial channel and one end of the heating wire being connected to the connecting ring. The protective tube expands under the heating action of the heating part, so that the axial channel is expanded to allow the line to pass through. The device has a small outer diameter and good flexibility at room temperature, is easy to thread into a long and narrow curved cavity, forms a smooth channel after being positioned by heating expansion, can greatly reduce the threading difficulty, protects the line sheath from being damaged, and can be reused.

Description

Technical Field

[0001] This invention belongs to the field of coal mine maintenance technology, specifically relating to a wire threading auxiliary device and a wire threading method. Background Technology

[0002] Hydraulic supports are the core support equipment for fully mechanized mining faces. Their structural components, such as the top beam, shield beam, and base, are often designed as box-shaped cavities to balance strength and lightweight design. Multiple hydraulic lines and cables need to be routed inside these cavities to connect spray devices, jacks, sensors, and other actuators and sensors. During assembly and maintenance, threading these flexible hoses or cables through the narrow, winding cavities within the structural components is an extremely difficult operation.

[0003] Due to the extremely confined space and the winding and complex path, methods such as threading with wire or manually threading are currently commonly used. However, these methods are very easy to scratch the outer sheath of the hose or cable, causing the hose or cable to become unusable. Summary of the Invention

[0004] This invention aims to at least partially solve one of the technical problems in related technologies. To this end, embodiments of this invention propose a wiring assistance device and a wiring method. This device can protect the wiring during the wiring process and improve the operational stability of the wiring after installation.

[0005] The thread-threading aid device according to an embodiment of the present invention includes:

[0006] The protective tube is spiral-shaped, and an axial channel is formed inside the protective tube to accommodate the passage of the circuit. The protective tube is made of a material that expands with heat. The connecting part includes a connecting ring and a traction line. The connecting ring is connected to one end of the protective tube, and the traction line is connected to the connecting ring. The traction line is used to pull the protective tube to move. The heating element includes a heating wire that passes through the axial channel, and one end of the heating wire is connected to the connecting ring. The protective tube expands under the heating action of the heating element, thereby enlarging the axial channel and facilitating the passage of the line through the axial channel.

[0007] The threading auxiliary device of this invention features a spiral-shaped protective tube that expands upon heating. At room temperature, the protective tube has a small outer diameter and good flexibility, allowing it to easily penetrate the narrow, curved cavities inside structural components under the pull of the traction wire. Upon reaching the predetermined position, the protective tube is heated by a heating wire, causing it to expand and widen the axial channel to form a clear path for the wire. The wire to be threaded can then be easily introduced from one end and led out from the other. This threading method avoids scratches on the wire sheath from burrs, weld beads, or rust inside the structural components, improving threading efficiency and operational safety, and ensuring the operational stability of the threaded wire.

[0008] In some embodiments, the protective tube is made of nickel-titanium shape memory alloy material, and the protective tube is tightly wound at room temperature, with adjacent coils pressed tightly against each other.

[0009] In some embodiments, the connecting portion further includes a connector and a plurality of retaining rings, the connector being disposed at one end of the connector, and the plurality of retaining rings being spaced apart along the circumferential direction at the other end of the connector, the retaining rings being connected to the protective tube by a rope.

[0010] In some embodiments, the protective tube is provided with a connection hole, through which the rope passes and connects to the protective tube.

[0011] In some embodiments, the end of the connector that is connected to the connecting ring is provided with a chamfer so that the connector can avoid obstacles under the traction of the traction line.

[0012] In some embodiments, the connector is cylindrical, and the diameter of the connector is larger than the diameter of the protective tube at room temperature.

[0013] In some embodiments, the connecting portion further includes a threaded hole formed on one end face of the connecting head away from the connecting ring, and the heating portion includes a connecting block connected to the end of the heating wire, the connecting block being threaded into the threaded hole.

[0014] In some embodiments, the heating element further includes a first pole connected between the heating wire and the connecting block. The first pole is exposed outside the threaded hole, and a chamfer is provided at the end of the first pole away from the connecting block so that the heating element can exit the axial channel after the protective tube is heated.

[0015] In some embodiments, the heating element further includes a second electrode disposed at the end of the heating wire away from the first electrode.

[0016] The threading method of this invention, utilizing any of the threading auxiliary devices described above, includes the following steps: Traction: Pull the traction line to insert the protective tube into the target cavity inside the structural component, wherein the protective tube is spiral-shaped and made of a heat-expanding material, and an axial channel is formed inside the protective tube to accommodate the passage of the line. Heating expansion: The protective tube is heated by a heating wire, causing it to expand and thus enlarging the axial channel; Threading: The line to be threaded is introduced into one end of the protective pipe, and the enlarged axial channel is led out from the other end.

[0017] The wire threading method of this invention, using the aforementioned wire threading auxiliary device, achieves a workflow of threading the tube first, then expanding, and finally threading the wire through three steps: traction, heating expansion, and threading. Compared with existing technologies, the difficulty of threading is significantly reduced. During the traction step, the protective tube is in a tightly spiral state at room temperature, with a small outer diameter and good flexibility, easily conforming to the narrow and curved cavity path inside the structural component and bypassing obstacles such as reinforcing ribs. This solves the problems of easy jamming and low efficiency of traditional wire threading methods. The resistance to wire passage is minimal. After the heating expansion step, the axial channel of the protective tube expands into a smooth and unobstructed wire path. When the wire to be threaded is introduced from one end and led out from the other end, there is almost no resistance, avoiding direct contact between the wire sheath and the burrs or weld beads on the inner wall of the cavity, fundamentally eliminating the risk of scratches. The operation is simple and can be completed by a single person. The entire method only requires three actions: pulling the traction line, connecting the power supply for heating, and pushing the wire. There is no need to splice pipe sections one by one in a narrow space or repeatedly thread the wire through the cavity. A single person can easily complete the task, significantly shortening maintenance time. The protective tube is reusable. After threading, it cools and returns to its contracted state, allowing it to be extracted and recycled from the cavity. It retains its shape memory properties even after thousands of thermal cycles. One device can serve the assembly and maintenance of multiple pieces of equipment. It is highly adaptable, allowing for the selection of different specifications of protective tubes and heating parameters according to actual needs. It is suitable for internal threading operations in various structural components such as hydraulic support top beams, shield beams, and bases, as well as other similar scenarios. Attached Figure Description

[0018] Figure 1 This is an overall schematic diagram of the present invention.

[0019] Figure 2 This is a schematic diagram illustrating the changing states of the protective tube in this invention.

[0020] Figure 3 This is a schematic diagram illustrating the changes in the usage status of the protective tube in this invention.

[0021] Figure 4 This is a schematic diagram of the connecting part in this invention.

[0022] Figure 5 This is a schematic diagram of the connecting ring in this invention.

[0023] Figure 6 This is a schematic diagram of the threaded hole in this invention.

[0024] Figure 7 This is a schematic diagram of the heating element in this invention.

[0025] Figure label: 1. Protective tube; 2. Connecting part; 21. Connecting ring; 22. Traction line; 23. Connecting head; 24. Retaining ring; 25. Threaded hole; 3. Heating section; 31. Heating wire; 32. Connecting block; 33. First pole; 34. Second pole. Detailed Implementation

[0026] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0027] like Figures 1-7 As shown, the threading aid device of this embodiment includes a protective tube 1, a connecting part 2, and a heating part 3. The protective tube 1 is spiral-shaped, and an axial channel for accommodating the passage of the wire is formed inside the protective tube 1. The protective tube 1 is made of a material that expands with heat. The connecting part 2 includes a connecting ring 21 and a traction wire 22. The connecting ring 21 is connected to one end of the protective tube 1, and the traction wire 22 is connected to the connecting ring 21. The traction wire 22 is used to pull the protective tube 1 to move. The heating part 3 includes a heating wire 31, which passes through the axial channel, and one end of the heating wire 31 is connected to the connecting ring 21. The protective tube 1 expands under the heating action of the heating part 3, thereby widening the axial channel and facilitating the passage of the wire.

[0028] The threading auxiliary device of this invention features a spiral-shaped protective tube that expands upon heating. At room temperature, the protective tube has a small outer diameter and good flexibility, allowing it to easily penetrate the narrow, curved cavities inside structural components under the pull of the traction wire. Upon reaching the predetermined position, the protective tube is heated by a heating wire, causing it to expand and widen the axial channel to form a clear path for the wire. The wire to be threaded can then be easily introduced from one end and led out from the other. This threading method avoids scratches on the wire sheath from burrs, weld beads, or rust inside the structural components, improving threading efficiency and operational safety, and ensuring the operational stability of the threaded wire.

[0029] Specifically, the protective tube 1 is spiral-shaped, with a hollow interior forming an axial channel. The protective tube 1 is made of a heat-expanding material, and at room temperature it is in a contracted state. At this temperature, the outer diameter of the protective tube 1 is small, and adjacent coils are close together or even pressed against each other, giving the entire protective tube 1 good flexibility and allowing it to conform to the bending path of the structural component cavity. When the protective tube 1 is heated to a certain temperature, its material expands, the pitch of the spiral increases, and the inner and outer diameters expand simultaneously, transforming the axial channel into a smooth wiring path.

[0030] In some embodiments, the protective tube 1 is made of nickel-titanium shape memory alloy. At room temperature, the protective tube 1 is tightly wound, with adjacent coils pressed together. Nickel-titanium shape memory alloy possesses excellent shape memory effect and superelasticity. At room temperature (martensitic state), it is tightly wound with a minimized outer diameter and optimal flexibility. When heated above the austenitic phase transformation temperature, it recovers its preset shape memory, unwinds into a spiral, and expands its axial channels. Nickel-titanium shape memory alloy can withstand thousands of thermal cycles without significant performance degradation, making the threading aid reusable.

[0031] Furthermore, the spiral structure and material selection of the protective tube 1 can be designed according to actual wiring requirements. For example, the outer diameter of the protective tube 1 at room temperature can be designed to be 15-20mm, and the inner diameter can be expanded to 25-35mm after expansion to accommodate hoses or cables of different specifications. The inner wall of the protective tube 1 can be further coated with polytetrafluoroethylene to reduce frictional resistance during wiring.

[0032] Specifically, the connecting part 2 includes a connecting ring 21 and a traction line 22. The connecting ring 21 is connected to one end of the protective tube 1, and the traction line 22 is connected to the connecting ring 21. During insertion, the operator pulls the traction line 22, and the traction force is transmitted to the protective tube 1 through the connecting ring 21, causing the protective tube 1 to move along a predetermined path. The traction line 22 can be made of a high-strength flexible rope, such as aramid rope or stainless steel wire rope, which has good tensile strength and flexibility.

[0033] In some embodiments, the connecting portion 2 further includes a connector 23 and a plurality of retaining rings 24. A connector 21 is disposed at one end of the connector 23, and a plurality of retaining rings 24 are spaced apart along the circumferential direction at the other end of the connector 23. The retaining rings 24 are connected to the protective tube 1 via a rope. By providing the connector 23 and the plurality of retaining rings 24, a reliable connection between the traction line 22 and the protective tube 1 is achieved. The spaced arrangement of the plurality of retaining rings 24 along the circumferential direction ensures that the traction force is evenly distributed on the end circumference of the protective tube 1, preventing the protective tube 1 from becoming skewed or damaged due to excessive local stress during traction.

[0034] Furthermore, the protective tube 1 is provided with connection holes, through which the rope passes to connect with the protective tube 1. The connection holes can be pre-drilled on each coil at the end of the protective tube 1, and the rope passes through each connection hole in sequence to fasten the protective tube 1 to the fixing ring 24. This connection method is simple and reliable, and facilitates on-site assembly and disassembly.

[0035] Furthermore, the end of the connector 23 connected to the connecting ring 21 is chamfered to facilitate the connector 23 avoiding obstacles under the traction of the traction line 22. When there are protruding obstacles such as reinforcing ribs or welding flash inside the cavity of the structural component, the chamfered structure can guide the connector 23 to smoothly slide over the obstacles, reducing the risk of jamming and improving the success rate of insertion.

[0036] Furthermore, the connector 23 is cylindrical, and its diameter is larger than that of the protective tube 1 at room temperature. The cylindrical structure of the connector 23 provides good guidance when moving within the cavity, and its slightly larger diameter than the protective tube 1 helps to center it, preventing the end of the protective tube 1 from getting into gaps in the cavity sidewall during traction. Simultaneously, the end face of the connector 23 can be designed as an arc surface or a conical surface to further reduce traction resistance.

[0037] In some embodiments, the connecting portion 2 further includes a threaded hole 25, which is formed on the end face of the connecting head 23 away from the connecting ring 21. The threaded hole 25 is used to thread into the connecting block 32 of the heating portion 3 to achieve detachable fixation of the end of the heating wire 31.

[0038] Specifically, the heating part 3 includes a heating wire 31, which passes through the axial channel of the protective tube 1, and one end of the heating wire 31 is connected to the connecting ring 21. When the heating wire 31 is energized, it generates heat, heating the protective tube 1 to a temperature above the phase transition temperature, triggering the expansion and deformation of the protective tube 1. The heating wire 31 can be made of insulated resistance wire, such as Teflon-coated nickel-chromium alloy wire, which has good flexibility and heat resistance.

[0039] In some embodiments, the heating part 3 further includes a connecting block 32, which is connected to the end of the heating wire 31 and threaded into the threaded hole 25. Through the threaded engagement of the connecting block 32 and the threaded hole 25, the end of the heating wire 31 is securely fixed to the connector 23, allowing the heating wire 31 to move together with the protective tube 1 during traction, preventing the heating wire 31 from coming out of the axial channel. When disassembly is required, simply rotating the connecting block 32 allows it to be removed from the threaded hole 25, making the operation convenient.

[0040] Furthermore, the heating section 3 also includes a first pole 33, which is connected between the heating wire 31 and the connecting block 32. The first pole 33 is exposed on the outside of the threaded hole 25, and the end of the first pole 33 away from the connecting block 32 is chamfered to facilitate the retraction of the heating section 3 from the axial channel after the protective tube 1 has been heated. The first pole 33 serves as an electrical connection terminal of the heating wire 31, used to connect to the positive or negative terminal of an external power source. Since the first pole 33 is exposed on the outside of the threaded hole 25, even after the connecting block 32 is screwed into the threaded hole 25, the first pole 33 remains exposed on the outside of the connector 23, facilitating wiring. The chamfered structure at the end of the first pole 33 reduces scraping against the inner wall of the protective tube 1 during retraction after heating, preventing jamming.

[0041] Furthermore, the heating element 3 also includes a second electrode 34, which is located at the end of the heating wire 31 furthest from the first electrode 33. The second electrode 34 serves as another electrical connection terminal of the heating wire 31, connected to the other pole of an external power supply. The first electrode 33 and the second electrode 34 are respectively connected to the positive and negative poles of the power supply, forming a complete heating circuit. The second electrode 34 can be configured with a structure similar to the first electrode 33, or as a simple lead-out terminal; the specific form can be determined according to the actual application scenario.

[0042] During operation, the heating wire 31 is passed through the axial channel of the protective tube 1, so that the first pole 33 and the connecting block 32 at one end protrude from the end of the protective tube 1. The connecting block 32 is screwed into the threaded hole 25 of the connector 23, fixing the first pole 33 relative to the connector 23. Then, the second pole 34 and the traction wire 22 are led to the operator's side. Pulling the traction wire 22 pulls the protective tube 1, connector 23, and heating wire 31 together into the cavity of the structural component until the protective tube 1 reaches the predetermined position. Subsequently, the first pole 33 and the second pole 34 are connected to an external power source, and the heating wire 31 is energized and heats up, heating the protective tube 1. The protective tube 1 expands due to heat, and the axial channel widens. Afterward, the power is disconnected, the connecting block 32 is rotated to separate it from the threaded hole 25, and the heating wire 31 is pulled from the other end of the protective tube 1 to withdraw it from the axial channel. At this time, a clear wiring channel is formed inside the protective tube 1. Finally, the hose or cable to be threaded is introduced into one end of the protective tube 1, and the enlarged axial channel is led out from the other end, completing the threading operation. After threading is completed, the protective tube 1 can be allowed to cool naturally and return to its contracted state. Then, the protective tube 1 can be pulled out of the cavity for recycling and reuse.

[0043] The threading method of this invention, using the above-mentioned threading auxiliary device, includes the following steps: Traction: Pull the traction line 22 to insert the protective tube 1 into the target cavity inside the structural component. The protective tube 1 is spiral-shaped and made of a heat-expanding material. An axial channel is formed inside the protective tube 1 to accommodate the passage of the line.

[0044] Heating expansion: The protective tube 1 is heated by the heating wire 31, causing the protective tube 1 to expand, thereby expanding the axial channel.

[0045] Threading: The line to be threaded is introduced into one end of the protective pipe 1, and the enlarged axial channel is led out from the other end.

[0046] The above-described wiring method utilizes the small outer diameter and good flexibility of the protective tube 1 at room temperature. It is easily threaded into the narrow, curved cavity using the traction wire 22. Once in place, the heating wire 31 heats the tube in situ, causing it to expand and create a clear passage for the wiring. After wiring is complete, the protective tube 1 can be cooled, contracted, and pulled out for recycling. The entire operation is simple and quick, requiring only one person, significantly reducing maintenance time and effectively protecting the wiring from damage.

[0047] The wire threading method of this invention, using the aforementioned wire threading auxiliary device, achieves a workflow of threading the tube first, then expanding, and finally threading the wire through three steps: traction, heating expansion, and threading. Compared with existing technologies, the difficulty of threading is significantly reduced. During the traction step, the protective tube is in a tightly spiral state at room temperature, with a small outer diameter and good flexibility, easily conforming to the narrow and curved cavity path inside the structural component and bypassing obstacles such as reinforcing ribs. This solves the problems of easy jamming and low efficiency of traditional wire threading methods. The resistance to wire passage is minimal. After the heating expansion step, the axial channel of the protective tube expands into a smooth and unobstructed wire path. When the wire to be threaded is introduced from one end and led out from the other end, there is almost no resistance, avoiding direct contact between the wire sheath and the burrs or weld beads on the inner wall of the cavity, fundamentally eliminating the risk of scratches. The operation is simple and can be completed by a single person. The entire method only requires three actions: pulling the traction line, connecting the power supply for heating, and pushing the wire. There is no need to splice pipe sections one by one in a narrow space or repeatedly thread the wire through the cavity. A single person can easily complete the task, significantly shortening maintenance time. The protective tube is reusable. After threading, it cools and returns to its contracted state, allowing it to be extracted and recycled from the cavity. It retains its shape memory properties even after thousands of thermal cycles. One device can serve the assembly and maintenance of multiple pieces of equipment. It is highly adaptable, allowing for the selection of different specifications of protective tubes and heating parameters according to actual needs. It is suitable for internal threading operations in various structural components such as hydraulic support top beams, shield beams, and bases, as well as other similar scenarios.

[0048] Specifically, the protective tube is tightly spirally wound at room temperature (martensitic state), where its outer diameter is at its minimum, the axial channel is contracted, and its overall flexibility is optimal. The operator pulls the traction wire, and the traction force is transmitted to the protective tube through the connecting ring, causing it to move along a predetermined path within the structural component's cavity. Due to its small and flexible outer diameter, the protective tube can easily pass through bends and narrow areas. Once the protective tube reaches the target position, it is heated by a heating wire. The heating wire passes through the axial channel of the protective tube, with one end fixed to the connecting ring. When energized, the heating wire heats evenly, transferring heat to the protective tube. The heated protective tube's temperature rises above the phase transition temperature of its thermally expanding material, triggering a shape memory effect or thermal expansion effect. The protective tube then returns to its memory-enhanced unfolded state: the spiral pitch increases, the coil layers separate, the outer and inner diameters expand simultaneously, and the axial channel changes from a contracted state to a clear wiring path.

[0049] At this point, the heating wire has completed its function and can be withdrawn from the axial channel (by loosening the connector, etc.).

[0050] Finally, the hose or cable to be installed is introduced into one end of the protective conduit, and the enlarged axial channel is led out from the other end. The channel diameter is large enough to accommodate the target line, and the line is pushed smoothly without jamming.

[0051] After threading is completed, the protective tube is allowed to cool naturally or with the aid of air cooling. When the temperature drops below the martensitic transformation temperature, the protective tube regains its flexibility and can be subjected to axial tension to return it to a tight spiral state. Then, the protective tube is pulled out of the cavity and recycled for later use.

[0052] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0053] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0054] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0055] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0056] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0057] Although the above embodiments have been shown and described, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any changes, modifications, substitutions and variations made to the above embodiments by those skilled in the art are within the protection scope of the present invention.

Claims

1. A threading aid device, characterized in that, include: The protective tube (1) is spiral-shaped, and an axial channel for accommodating the passage of the line is formed inside the protective tube (1). The protective tube (1) is made of a material that expands with heat. The connecting part (2) includes a connecting ring (21) and a traction line (22). The connecting ring (21) is connected to one end of the protective tube (1), and the traction line (22) is connected to the connecting ring (21). The traction line (22) is used to pull the protective tube (1) to move. Heating section (3), the heating section (3) includes heating wire (31), the heating wire (31) passes through the axial channel, and one end of the heating wire (31) is connected to the connecting ring (21); The protective tube (1) expands under the heating action of the heating part (3), thereby expanding the axial channel and facilitating the passage of the line through the axial channel.

2. The threading auxiliary device according to claim 1, characterized in that, The protective tube (1) is made of nickel-titanium shape memory alloy material. The protective tube (1) is tightly wound at room temperature, and the adjacent coils are close to each other.

3. The threading auxiliary device according to claim 1, characterized in that, The connecting part (2) further includes a connector (23) and a plurality of fixing rings (24). The connector (21) is disposed at one end of the connector (23), and the plurality of fixing rings (24) are disposed at intervals along the circumferential direction at the other end of the connector (23). The fixing rings (24) are connected to the protective tube (1) by ropes.

4. The threading auxiliary device according to claim 3, characterized in that, The protective tube (1) is provided with a connection hole, and the rope passes through the connection hole and connects to the protective tube (1).

5. The threading auxiliary device according to claim 3, characterized in that, The end of the connector (23) connected to the connecting ring (21) is chamfered so that the connector (23) can avoid obstacles under the traction of the traction line (22).

6. The thread-threading auxiliary device according to claim 3, characterized in that, The connector (23) is cylindrical, and the diameter of the connector (23) is larger than the diameter of the protective tube (1) at room temperature.

7. The thread-threading auxiliary device according to claim 3, characterized in that, The connecting part (2) also includes a threaded hole (25), which is opened on one end face of the connector (23) away from the connecting ring (21). The heating part (3) includes a connecting block (32), which is connected to the end of the heating wire (31) and is threaded in the threaded hole (25).

8. The threading auxiliary device according to claim 7, characterized in that, The heating part (3) further includes a first pole (33), which is connected between the heating wire (31) and the connecting block (32). The first pole (33) is exposed on the outside of the threaded hole (25). The end of the first pole (33) away from the connecting block (32) is chamfered so that the heating part (3) can exit the axial channel after the protective tube (1) is heated.

9. The thread-threading auxiliary device according to claim 8, characterized in that, The heating part (3) further includes a second pole (34), which is disposed at the end of the heating wire (31) away from the first pole (33).

10. A threading method, comprising the threading auxiliary device according to any one of claims 1-9, characterized in that, Includes the following steps: Traction: Pull the traction line to insert the protective tube into the target cavity inside the structural component, wherein the protective tube is spiral-shaped and made of a heat-expanding material, and an axial channel is formed inside the protective tube to accommodate the passage of the line. Heating expansion: The protective tube is heated by a heating wire, causing it to expand and thus enlarging the axial channel; Threading: The line to be threaded is introduced into one end of the protective pipe, and the enlarged axial channel is led out from the other end.

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