Low-smoke halogen-free flame-retardant fireproof power cable

Abstract

The invention relates to the technical field of power cables, and discloses a low-smoke halogen-free flame-retardant fire-resistant power cable, the power cable sequentially comprises a conductor layer, an insulating layer, a shielding layer, a flame-retardant fire-resistant layer and a sheath layer from inside to outside, and production equipment for producing the low-smoke halogen-free flame-retardant fire-resistant power cable comprises a bottom plate extrusion cylinder, a machine head shell is arranged at one end of the extrusion barrel, a discharging assembly is arranged in the machine head shell and comprises a transition barrel arranged in the machine head shell, a fixing ring is rotationally connected to the side wall of the transition barrel, a feeding port is formed in one side of the fixing ring and communicates with the extrusion pipe, and a discharging port is formed in the inner ring of the transition barrel. The scheme has the beneficial effect that the outer surface of the cable can be uniformly covered with a raw material in a molten state when the raw material is extruded, and the problem that the outer surface of the cable cannot be uniformly coated with the molten raw material in the extrusion process of a thermoplastic extruder in the prior art is solved.

Description

Technical Field

[0001] The invention relates to the technical field of power cables, in particular to a low-smoke, halogen-free, flame-retardant and fire-resistant power cable. Background Art

[0002] In cable production, high-purity copper or aluminum is first drawn and twisted into conductors; then the insulating material is wrapped around the conductor with an extruder to form an insulating layer; a copper tape or copper wire shielding layer is set by wrapping or weaving technology; then a flame retardant and fire-resistant layer consisting of mica tape, ceramic silicone rubber, and glass fiber braided layer is made; finally, a low-smoke, halogen-free, flame retardant sheath material is wrapped with an extruder to form a sheath layer. During this process, the process parameters must be strictly controlled in each link to ensure that the cable quality meets the standards.

[0003] Low smoke halogen-free cable is an environmentally friendly cable that does not produce toxic smoke and corrosive gases when burned. This cable usually uses cross-linked polyethylene and other halogen-free polymers as insulation materials, and magnesium oxide or magnesium hydroxide and other halogen-free flame retardants as flame retardants. It has excellent environmental performance and high flame retardant performance. The coating of most cables currently used is composed of polyethylene, polyvinyl chloride or thermoplastic polyurethane. Chlorine-containing plastics will release toxic hydrogen chloride when on fire, and will produce hydrochloric acid if they come into contact with water. Low smoke halogen-free cable will not release hydrogen halide or other acids when on fire, which can reduce the toxic and corrosive gases produced when it burns. The smoke concentration is low, the visibility is high, and the amount of harmful gas released is small, which is convenient for personnel evacuation.

[0004] However, in the prior art, the sheath layer of the cable is usually made by using a thermoplastic extruder to extrude molten raw materials onto the outer layer of the cable, and then using a cooling device to fix the raw materials on the outside of the cable to form a sheath layer. However, the thermoplastic extruder in the prior art cannot evenly apply the molten raw materials to the outer surface of the cable during the extrusion process, which will result in the produced cables having different loads that can be borne under the same cross-section, which will cause a series of problems such as damage to the cable during use; therefore, it does not meet the existing needs, and we have proposed a low-smoke, halogen-free, flame-retardant and fire-resistant power cable. Summary of the invention

[0005] The present invention provides a low-smoke, halogen-free, flame-retardant and fire-resistant power cable, which has the beneficial effect that the raw materials in a molten state can be evenly covered on the outer surface of the cable during extrusion, thereby solving the problem that the thermoplastic extruder of the prior art mentioned in the above background technology cannot evenly apply the molten raw materials to the outer surface of the cable during the extrusion process.

[0006] The present invention provides the following technical solution: a low-smoke, halogen-free, flame-retardant and fire-resistant power cable, which comprises, from the inside to the outside, a conductor layer, an insulating layer, a shielding layer, a flame-retardant and fire-resistant layer, and a sheath layer.

[0007] The conductor layer is made of brass.

[0008] The insulating layer is made of a composite of cross-linked polyethylene and an inorganic flame retardant.

[0009] The shielding layer is made of copper wire braided mesh.

[0010] The flame retardant and fire resistant layer is made of mica tape.

[0011] The sheath layer is made of thermoplastic elastomer.

[0012] The present invention also includes a production device for low-smoke, halogen-free, flame-retardant and fire-resistant power cable, including an extrusion device, the extrusion device includes a bottom plate extrusion barrel, a machine head shell is arranged at one end of the extrusion barrel, an extrusion tube is arranged between the machine head shell and the extrusion barrel, a discharge assembly is arranged in the machine head shell, and a cable inlet pipe and a cable outlet pipe are arranged in the machine head shell.

[0013] The discharge assembly includes a transition tube arranged in the head shell, the transition tube is hollow in design, the side wall of the transition tube is rotatably connected with a fixing ring, one side of the fixing ring is provided with a feed port, the feed port is connected with the extrusion tube, the fixing ring is fixedly connected with the extrusion tube, the inner ring of the transition tube is provided with a discharge port, and the discharge port is connected with the cable inlet pipe and the cable outlet pipe.

[0014] As an optional solution for the production equipment of a low-smoke, halogen-free, flame-retardant and fire-resistant power cable described in the present invention, a motor is installed in the extrusion barrel, the output end of the motor is fixedly connected to a spiral extrusion shaft, the side wall of the spiral extrusion shaft is provided with a baffle, and the baffle is fixedly connected to the extrusion barrel.

[0015] As an optional solution for the production equipment of a low-smoke, halogen-free, flame-retardant and fire-resistant power cable described in the present invention, wherein: a rotating groove is opened in the transition cylinder, a fixed ring is rotatably connected in the rotating groove, a No. 1 anti-slip ring is fixedly connected to the upper and lower ends of the fixed ring, the No. 1 anti-slip ring is rotatably connected in the No. 1 anti-slip groove, the No. 1 anti-slip groove is opened in the transition cylinder, a No. 2 anti-slip ring is fixedly connected to the upper and lower ends of the transition cylinder, the No. 2 anti-slip ring is rotatably connected in the No. 2 anti-slip groove, the No. 2 anti-slip groove is opened in the cable inlet pipe and the cable outlet pipe, the No. 1 anti-slip ring has a T-shaped cross-section, and the No. 2 anti-slip ring has an L-shaped cross-section.

[0016] As an optional solution for the production equipment of a low-smoke, halogen-free, flame-retardant and fire-resistant power cable described in the present invention, a concentric device is arranged in the transition cylinder, and the concentric device includes concentric rollers arranged in the transition cylinder, and concentric rollers are fixedly connected to both sides of the concentric rollers, and the concentric rollers are rotatably connected in a support plate, and the bottom of the support plate is fixedly connected to one side of a lifting shaft, and the lifting shaft is installed in the transition cylinder.

[0017] As an optional solution for the production equipment of a low-smoke, halogen-free, flame-retardant and fire-resistant power cable described in the present invention, the lifting shaft is slidably connected in the lifting groove, the lifting shaft and the lifting groove are connected by a lifting spring, and the lifting groove is opened in the transition cylinder.

[0018] As an optional solution for the production equipment of a low-smoke, halogen-free, flame-retardant and fire-resistant power cable described in the present invention, a rotating assembly is provided at the extrusion tube, and the rotating assembly includes a cross rotating groove opened in the extrusion tube, a cross rotating shaft is rotatably connected in the cross rotating groove, a turbine fan is installed on the top of the cross rotating shaft, and the turbine fan is arranged in the extrusion tube, and a No. 1 gear is fixedly connected to the bottom of the cross rotating shaft, and the No. 1 gear is meshingly connected with a gear ring, and the gear ring is fixedly connected to the side wall of the transition tube.

[0019] As an optional solution for the production equipment of a low-smoke, halogen-free, flame-retardant and fire-resistant power cable described in the present invention, a thickness adjustment component is arranged on the top of the transition tube, and the thickness adjustment component includes an adjustment groove opened in the transition tube, an adjustment rod is slidably connected in the adjustment groove, an adjustment spring is fixedly connected to one side of the adjustment rod, and the other end of the adjustment spring is installed in the adjustment groove.

[0020] As an optional solution for the production equipment of a low-smoke, halogen-free, flame-retardant and fire-resistant power cable described in the present invention, a sliding drive groove is provided at the bottom of the adjusting rod, the sliding drive groove is resisted by the sliding drive rod, the sliding drive rod is slidably connected in the drive slide groove, and the drive slide groove is provided in the transition tube.

[0021] As an optional solution for the production equipment of a low-smoke, halogen-free, flame-retardant and fire-resistant power cable described in the present invention, a hydraulic channel is opened in the transition cylinder, and the hydraulic channel is connected by straight grooves at two ends and a curved groove at one end, one end of the hydraulic channel is connected to the driving slide groove, and the other end of the hydraulic channel is connected to the lifting groove, and the hydraulic channel, the driving slide groove and the lifting groove are filled with hydraulic oil.

[0022] The present invention has the following beneficial effects: 1. The low-smoke, halogen-free, flame-retardant and fire-resistant power cable is designed to control the timing and amount of molten raw materials covering the cable surface through the design of the discharge component. When the head shell in the prior art extrudes the material, the raw material first covers one side of the cable, and then the cable is wrapped in the raw material through the subsequent delivery of the raw material. This extrusion method causes too much raw material to be bonded to one side of the cable, while the other side has less raw material, which leads to uneven thickness of the protective layer of the cable finally produced, resulting in weak local protection effect. In this solution, through the design of the discharge component, the raw materials can be covered on the outer surface of the cable at the same time and in the same amount, thereby ensuring that the thickness of the outer protective layer of the cable is uniform and even, thereby improving the protection effect of the cable protective layer.

[0023] 2. The concentric device of the low-smoke halogen-free flame-retardant and fire-resistant power cable is designed to ensure that the cable is coaxial with the transition tube before being covered by the raw material. The coaxiality of the transition tube and the cable can further ensure the uniformity of the thickness of the outer protective layer. When the cable enters the transition tube through the cable inlet pipe, the cable first hits the side wall of the concentric roller. Due to the circumferential design of the concentric device, the four concentric rollers can clamp the cable under the drive of the lifting spring, and the concentric rollers are installed in the transition tube. Through this clamping, the concentricity of the cable and the transition tube can be guaranteed, thereby ensuring the uniformity of the thickness of the cable outer protective layer. The telescopic design of the lifting shaft and the lifting groove can adapt to cables of different sizes.

[0024] 3. The thickness adjustment component of the low-smoke, halogen-free, flame-retardant and fire-resistant power cable is designed to adjust the thickness of the outer protective layer according to the diameter of the cable. Since the thicker the cable, the thicker the protective layer required. When the lifting shaft is squeezed by the cable and slides inward in the lifting groove, the hydraulic oil in the lifting groove is squeezed, and through the connection of the hydraulic channel, the sliding drive rod in the driving slide groove at the other end is driven to slide upward, and then the sliding drive rod is driven to resist the sliding drive groove at the bottom of the adjusting rod, and then the adjusting rod is driven to slide backward. The sliding of the adjusting rod can change the maximum diameter entering the cable outlet pipe. The scraper design at one end of the adjusting rod can scrape off the outer protective cover that exceeds the range, and the rotation of the transition cylinder further ensures the roundness of the cable and the thickness of the outer protective layer of the cable. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of the present invention.

[0026] Figure 2 It is a schematic diagram of the cross-sectional structure of the present invention.

[0027] Figure 3 For the present invention Figure 2 Schematic diagram of the local structure.

[0028] Figure 4For the present invention Figure 3 Enlarged structural diagram at A in the middle.

[0029] Figure 5 For the present invention Figure 4 B in the middle is a schematic diagram of the enlarged structure.

[0030] Figure 6 For the present invention Figure 4 Center C is a schematic diagram of the enlarged structure.

[0031] Figure 7 It is a schematic diagram of the cross-sectional structure of the concentric device of the present invention.

[0032] Figure 8 For the present invention Figure 4 D in the middle is a schematic diagram of the enlarged structure.

[0033] Fig. 9 It is a schematic diagram of the hydraulic channel structure of the present invention.

[0034] In the figure: 1. Extrusion equipment; 11. Extrusion barrel; 12. Motor; 13. Baffle; 14. Screw extrusion shaft; 15. Head housing; 16. Extrusion tube; 17. Cable inlet pipe; 18. Cable outlet pipe; 2. Discharge assembly; 21. Transition barrel; 22. Rotating groove; 23. Fixed ring; 24. Feed inlet; 25. No. 1 anti-slip groove; 26. No. 1 anti-slip ring; 27. Discharge port; 28. Discharge valve; 29. ​​No. 2 anti-slip groove; 210. No. 2 anti-slip ring; 3. Same as above Centering device; 31. Concentric roller; 32. Concentric roller; 33. Support plate; 34. Lifting shaft; 35. Lifting slot; 36. Lifting spring; 4. Rotating assembly; 41. Cross rotating slot; 42. Cross rotating shaft; 43. Turbofan; 44. No. 1 gear; 45. Gear ring; 5. Thickness adjustment assembly; 51. Adjusting slot; 52. Adjusting rod; 53. Adjusting spring; 54. Sliding drive slot; 55. Sliding drive rod; 56. Driving slide slot; 57. Hydraulic channel. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] Example 1: This example is intended to promote the solution of the problem that the thermoplastic extruder of the prior art cannot evenly apply the molten raw material to the outer surface of the cable during the extrusion process. Figures 1 to 9A low-smoke, halogen-free, flame-retardant and fire-resistant power cable, which comprises a conductor layer, an insulation layer, a shielding layer, a flame-retardant and fire-resistant layer, and a sheath layer from the inside to the outside.

[0037] The conductor layer is made of brass; The insulating layer is made of a composite of cross-linked polyethylene and an inorganic flame retardant; The shielding layer is made of copper wire braided mesh; The flame retardant and fire resistant layer is made of mica tape; The sheath layer is made of thermoplastic elastomer.

[0038] A production device for producing low-smoke, halogen-free, flame-retardant and fire-resistant power cables, including an extrusion device 1, the extrusion device 1 includes a bottom plate extrusion barrel 11, a head shell 15 is arranged at one end of the extrusion barrel 11, an extrusion tube 16 is arranged between the head shell 15 and the extrusion barrel 11, a discharge assembly 2 is arranged in the head shell 15, and a cable inlet pipe 17 and a cable outlet pipe 18 are arranged in the head shell 15.

[0039] A motor 12 is installed in the extrusion barrel 11 . A spiral extrusion shaft 14 is fixedly connected to the output end of the motor 12 . A baffle 13 is provided on the side wall of the spiral extrusion shaft 14 . The baffle 13 is fixedly connected in the extrusion barrel 11 .

[0040] The extrusion device 1 is configured to melt the molten raw material and cover it on the outer surface of the cable through the device, so that there is a protective layer on the outside of the cable to ensure the service life of the cable (the working principle and specific structure of the extrusion device 1 are prior art, so this solution will not be described in detail).

[0041] The discharge assembly 2 includes a transition barrel 21 arranged in the head housing 15. The transition barrel 21 is hollow in design. The side wall of the transition barrel 21 is rotatably connected to a fixing ring 23. A feed port 24 is provided on one side of the fixing ring 23. The feed port 24 is connected to the extrusion tube 16. The fixing ring 23 is fixedly connected to the extrusion tube 16. A discharge port 27 is provided on the inner ring of the transition barrel 21.

[0042] A rotating groove 22 is provided in the transition tube 21, and a fixed ring 23 is rotatably connected in the rotating groove 22. A No. 1 anti-slip ring 26 is fixedly connected to the upper and lower ends of the fixed ring 23. The No. 1 anti-slip ring 26 is rotatably connected in the No. 1 anti-slip groove 25. The No. 1 anti-slip groove 25 is provided in the transition tube 21. A No. 2 anti-slip ring 210 is fixedly connected to the upper and lower ends of the transition tube 21. The No. 2 anti-slip ring 210 is rotatably connected in the No. 2 anti-slip groove 29. The No. 2 anti-slip groove 29 is provided in the cable inlet pipe 17 and the cable outlet pipe 18.

[0043] The design of the discharge component 2 is used to control the timing and amount of the molten raw material (hereinafter referred to as the raw material) covering the cable surface. When the head shell 15 in the prior art extrudes the material, the raw material first covers one side of the cable, and then the cable is wrapped in the raw material through the subsequent delivery of the raw material. This extrusion method causes too much raw material to be bonded to one side of the cable, while the other side has less raw material, which leads to the thickness of the protective layer of the cable finally produced being not uniform, resulting in weak local protection effect. In this solution, through the design of the discharge component 2, the raw material can be covered on the outer surface of the cable at the same time and in the same amount, thereby ensuring that the thickness of the outer protective layer of the cable is uniform and even, thereby improving the protection effect of the cable protective layer.

[0044] When the raw material is extruded, the raw material first enters the cavity between the transition tube 21 and the fixing ring 23 (hereinafter referred to as the cavity) through the extrusion tube 16 and the feed port 24, and the discharge port 27 is used to discharge the raw material. Since a discharge valve 28 is provided in the discharge port 27, the discharge valve 28 is designed to block the discharge port 27. Therefore, when the cavity is not completely filled, the discharge valve 28 will not open. When the cavity is full of raw materials, the discharge valve 28 is squeezed by the raw materials and the discharge valves 28 are opened at the same time. At this time, since the extrusion rate of the extrusion device 1 is unchanged, it can be ensured that the raw material can pass through the discharge port 27 at the same rate to cover the outer wall of the cable to form an outer protective layer. Through this design, it can be ensured that the raw material is evenly covered on the outside of the cable, and its thickness is uniform.

[0045] Example 2: This example is intended to help solve the problem that if the cable side wall is not located at the center of the cable inlet pipe 17, the thickness of the outer protective sleeve may be uneven. This example is an explanation based on Example 1. For details, please refer to Figures 1 to 9 A concentric device 3 is provided in the transition tube 21, and the concentric device 3 includes a concentric roller 31 provided in the transition tube 21, and concentric rollers 32 are fixedly connected on both sides of the concentric roller 31. The concentric rollers 32 are rotatably connected in a support plate 33, and the bottom of the support plate 33 is fixedly connected to one side of a lifting shaft 34. The lifting shaft 34 is installed in the transition tube 21.

[0046] The lifting shaft 34 is slidably connected in the lifting slot 35 . The lifting shaft 34 and the lifting slot 35 are connected via a lifting spring 36 . The lifting slot 35 is provided in the filter barrel 21 .

[0047] The concentric device 3 is designed to ensure that the cable is coaxial with the transition tube 21 before being covered by the raw material. The coaxiality of the transition tube 21 and the cable can further ensure the uniformity of the thickness of the outer protective layer. When the cable enters the transition tube 21 through the cable inlet pipe 17, the cable first hits the side wall of the concentric roller 31. Due to the circular design of the concentric device 3, the four concentric rollers 31 can clamp the cable under the drive of the lifting spring 36, and the concentric rollers 31 are installed in the transition tube 21. Through this clamping, the concentricity of the cable and the transition tube 21 can be ensured, thereby ensuring the uniformity of the thickness of the cable outer protective layer. The telescopic design of the lifting shaft 34 and the lifting groove 35 can adapt to cables of different sizes.

[0048] A rotating assembly 4 is provided at the extrusion tube 16, and the rotating assembly 4 includes a cross rotating groove 41 opened in the extrusion tube 16, a cross rotating shaft 42 is rotatably connected in the cross rotating groove 41, a turbofan 43 is installed on the top of the cross rotating shaft 42, and the turbofan 43 is provided in the extrusion tube 16, a No. 1 gear 44 is fixedly connected to the bottom of the cross rotating shaft 42, and the No. 1 gear 44 is meshedly connected with a gear ring 45, and the gear ring 45 is fixedly connected to the side wall of the transition tube 21.

[0049] When the raw material passes through the extrusion tube 16, the turbine fan 43 is driven to rotate, and the turbine fan 43 is connected to the No. 1 gear 44 at the bottom through the cross rotating shaft 42, and the No. 1 gear 44 is meshed with the gear ring 45 on the side wall of the transition cylinder 21. Therefore, the rotation of the turbine fan 43 can drive the transition cylinder 21 to rotate synchronously. Through the design of the rotating component 4, the transition cylinder 21 can be driven to rotate, and then the concentric roller 31 can be driven to rotate synchronously. Since the concentric roller 31 squeezes the cable, the rotation of the concentric roller 31 can further ensure that the cable is always in the center of the transition cylinder 21, thereby further ensuring the uniformity of the thickness of the outer protective layer of the cable. At the same time, through the rotation of the transition cylinder 21, the discharge port 27 can be driven to further ensure the uniformity of the outer surface of the cable when discharging.

[0050] Embodiment 3: This embodiment is intended to promote the solution of the problem that the thickness of the outer protective layer to be covered varies according to the diameter of the cable. This embodiment is an explanation based on Embodiment 2. For details, please refer to Figures 1 to 9 A thickness adjustment component 5 is provided at the top of the transition tube 21. The thickness adjustment component 5 includes an adjustment groove 51 opened in the transition tube 21. An adjustment rod 52 is slidably connected in the adjustment groove 51. An adjustment spring 53 is fixedly connected to one side of the adjustment rod 52. The other end of the adjustment spring 53 is installed in the adjustment groove 51.

[0051] A sliding drive groove 54 is provided at the bottom of the adjusting rod 52 . The sliding drive groove 54 is resisted by a sliding drive rod 55 . The sliding drive rod 55 is slidably connected in a driving slide groove 56 . The driving slide groove 56 is provided in the transition tube 21 .

[0052] A hydraulic channel 57 is provided in the transition tube 21 . The hydraulic channel 57 is connected by straight grooves at two ends and a curved groove at one end. One end of the hydraulic channel 57 is connected to the driving slide groove 56 , and the other end of the hydraulic channel 57 is connected to the lifting groove 35 .

[0053] The thickness adjustment component 5 is designed to adjust the thickness of the outer protective layer according to the diameter of the cable. Since the thicker the cable, the thicker the protective layer required. When the lifting shaft 34 is squeezed by the cable and slides inward in the lifting groove 35, the hydraulic oil in the lifting groove 35 is squeezed, and through the connection of the hydraulic channel 57, the sliding drive rod 55 in the driving slide groove 56 at the other end is driven to slide upward, and then the sliding drive rod 55 is driven to resist the sliding drive groove 54 at the bottom of the adjusting rod 52, and then the adjusting rod 52 is driven to slide backward. Through the sliding of the adjusting rod 52, the maximum diameter entering the cable outlet pipe 18 can be changed. Through the scraper design at one end of the adjusting rod 52, the outer protective cover that exceeds the range can be scraped off, and through the rotation of the transition cylinder 21, the roundness of the cable is further guaranteed, and the thickness of the outer protective layer of the cable is further guaranteed.

[0054] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0055] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A low-smoke, halogen-free, flame-retardant and fire-resistant power cable, which comprises a conductor layer, an insulating layer, a shielding layer, a flame-retardant and fire-resistant layer, and a sheath layer from the inside to the outside, characterized in that: The conductor layer is made of brass; The insulating layer is made of a composite of cross-linked polyethylene and an inorganic flame retardant; The shielding layer is made of copper wire braided mesh; The flame retardant and fire resistant layer is made of mica tape; The sheath layer is made of thermoplastic elastomer.

2. A production device for a low-smoke, halogen-free, flame-retardant, and fire-resistant power cable, using the low-smoke, halogen-free, flame-retardant, and fire-resistant power cable according to claim 1, comprising an extrusion device (1), characterized in that: The extrusion device (1) comprises a bottom plate extrusion barrel (11), one end of the extrusion barrel (11) is provided with a head shell (15), an extrusion tube (16) is provided between the head shell (15) and the extrusion barrel (11), a discharge assembly (2) is provided in the head shell (15), and a cable inlet pipe (17) and a cable outlet pipe (18) are provided in the head shell (15); The discharge assembly (2) comprises a transition barrel (21) arranged in the head housing (15), the transition barrel (21) being of hollow design, a side wall of the transition barrel (21) being rotatably connected to a fixing ring (23), a side of the fixing ring (23) being provided with a feed port (24), the feed port (24) being in communication with the extrusion tube (16), the fixing ring (23) being fixedly connected to the extrusion tube (16), an inner ring of the transition barrel (21) being provided with a discharge port (27), a discharge valve (28) being installed in the discharge port (27), the discharge port (27) being in communication with the cable inlet pipe (17) and the cable outlet pipe (18).

3. The production equipment of a low-smoke, halogen-free, flame-retardant and fire-resistant power cable according to claim 2, characterized in that: A motor (12) is installed in the extrusion barrel (11), the output end of the motor (12) is fixedly connected to a spiral extrusion shaft (14), a baffle (13) is provided on the side wall of the spiral extrusion shaft (14), and the baffle (13) is fixedly connected in the extrusion barrel (11).

4. The production equipment of a low-smoke, halogen-free, flame-retardant and fire-resistant power cable according to claim 3 is characterized in that: A rotating groove (22) is provided in the transition tube (21), a fixed ring (23) is rotatably connected in the rotating groove (22), a No. 1 anti-slip ring (26) is fixedly connected at the upper and lower ends of the fixed ring (23), the No. 1 anti-slip ring (26) is rotatably connected in the No. 1 anti-slip groove (25), the No. 1 anti-slip groove (25) is provided in the transition tube (21), a No. 2 anti-slip ring (210) is fixedly connected at the upper and lower ends of the transition tube (21), the No. 2 anti-slip ring (210) is rotatably connected in the No. 2 anti-slip groove (29), the No. 2 anti-slip groove (29) is provided in the cable inlet pipe (17) and the cable outlet pipe (18).

5. The production equipment of a low-smoke, halogen-free, flame-retardant and fire-resistant power cable according to claim 2, characterized in that: A concentric device (3) is provided in the transition tube (21), and the concentric device (3) comprises a concentric roller (31) provided in the transition tube (21), and concentric rollers (32) are fixedly connected to both sides of the concentric roller (31), and the concentric rollers (32) are rotatably connected in a support plate (33), and the bottom of the support plate (33) is fixedly connected to one side of a lifting shaft (34), and the lifting shaft (34) is installed in the transition tube (21).

6. The production equipment of a low-smoke, halogen-free, flame-retardant and fire-resistant power cable according to claim 5, characterized in that: The lifting shaft (34) is slidably connected in the lifting groove (35); the lifting shaft (34) and the lifting groove (35) are connected via a lifting spring (36); and the lifting groove (35) is provided in the transition cylinder (21).

7. The production equipment of a low-smoke, halogen-free, flame-retardant and fire-resistant power cable according to claim 2, characterized in that: The extrusion tube (16) is provided with a rotating assembly (4), the rotating assembly (4) comprising a cross rotating groove (41) provided in the extrusion tube (16), a cross rotating shaft (42) rotatably connected in the cross rotating groove (41), a turbine fan (43) being installed on the top of the cross rotating shaft (42), the turbine fan (43) being provided in the extrusion tube (16), a first gear (44) being fixedly connected to the bottom of the cross rotating shaft (42), the first gear (44) being meshingly connected with a gear ring (45), the gear ring (45) being fixedly connected to the side wall of the transition tube (21).

8. The production equipment of a low-smoke, halogen-free, flame-retardant and fire-resistant power cable according to claim 6, characterized in that: A thickness adjustment component (5) is provided at the top of the transition tube (21), and the thickness adjustment component (5) comprises an adjustment groove (51) provided in the transition tube (21), an adjustment rod (52) being slidably connected in the adjustment groove (51), an adjustment spring (53) being fixedly connected to one side of the adjustment rod (52), and the other end of the adjustment spring (53) being installed in the adjustment groove (51).

9. The production equipment of a low-smoke, halogen-free, flame-retardant and fire-resistant power cable according to claim 8, characterized in that: A sliding drive groove (54) is provided at the bottom of the adjusting rod (52), the sliding drive groove (54) is abutted by a sliding drive rod (55), the sliding drive rod (55) is slidably connected in a driving slide groove (56), and the driving slide groove (56) is provided in the transition cylinder (21).

10. The production equipment of a low-smoke, halogen-free, flame-retardant and fire-resistant power cable according to claim 9, characterized in that: A hydraulic channel (57) is provided in the transition tube (21), the hydraulic channel (57) being connected by straight grooves at two ends and a curved groove at one end, one end of the hydraulic channel (57) being in communication with the driving slide groove (56), and the other end of the hydraulic channel (57) being in communication with the lifting groove (35).

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