Compression-resistant die for overhead cable production

Abstract

The utility model discloses a kind of die heads for pressure-resistant overhead cable production, it is related to cable production technical field, including shell, inner die sleeve and die core, the cavity is opened in the shell, the inner die sleeve and die core are respectively placed in the two ends of cavity along its axis, the center of the inner die sleeve is respectively opened with conical melt cavity and cylindrical setting cavity, heat conduction ring is embedded in melt cavity inner wall, the outer wall of heat conduction ring is fixedly connected with several heat conduction blocks, the end of several heat conduction blocks away from heat conduction ring penetrates inner die sleeve and cavity inner wall direct contact, heating block is worn in the position of shell corresponding heat conduction block, heating block and heat conduction block direct contact, electric heating jacket is sleeved on the outside of shell, the output end of electric heating jacket and heating block direct contact, cooling ring is embedded in the end of setting cavity away from melt cavity, cooling ring outer wall is nested with helical circulating pipe, the device has the characteristics of improving overhead cable production efficiency and quality.

Description

Technical Field

[0001] This utility model relates to the field of cable production technology, specifically to a die head for producing pressure-resistant overhead cables. Background Technology

[0002] Overhead cables are special cables used for power transmission at voltage levels of 35 kV and above, crossing valleys, rivers, or high-rise buildings in cities. Their structure typically consists of multiple high-strength galvanized steel or aluminum alloy cores as load-bearing cables, with several stranded hard aluminum or aluminum alloy conductors forming a conductive layer. A high-density polyethylene (HDPE), cross-linked polyethylene (XLPE), or tracking-resistant silicone rubber insulation / sheathing layer is then extruded over this conductive layer. To meet the requirements of long spans, high elevation differences, and strong wind loads, the cables must possess high tensile strength, resistance to flattening, and excellent insulation performance.

[0003] The insulation layer of existing overhead cables is generally produced using the "single screw extrusion-chain crosslinking" or "continuous vulcanization (CCV)" process: First, the metal wire core (or the conductor that has already been cabled) is introduced into the extruder head through the pay-off stand; then the extruder injects molten insulation material (temperature of about 180 ℃–220 ℃) ​​into the die cavity to cover the conductor; after that, the covered cable enters the high-temperature vulcanization tube to complete the crosslinking, and then undergoes multi-stage water cooling or air cooling for shaping; finally, it is wound into a reel by a traction, meter counting, and take-up cable winding device.

[0004] However, the above-mentioned general process has the following defects in the die head section: the molten insulation material extruded from the extruder loses temperature when it enters the die head, and it is prone to heat loss and solidification in the dead corner of the die cavity, resulting in frequent shutdowns for cleaning. The cooling efficiency during the cable extrusion process is low, and the linear speed needs to be reduced to ensure complete shaping, thus limiting production capacity.

[0005] Therefore, it is necessary to design a pressure-resistant overhead cable production die to improve the production efficiency and quality of overhead cables. Utility Model Content

[0006] The purpose of this invention is to address the shortcomings of existing technologies by providing a pressure-resistant overhead cable production die head, thereby solving the problems mentioned in the background section.

[0007] To solve the above-mentioned technical problems, this utility model provides the following technical solution: a die head for producing pressure-resistant overhead cables, comprising an outer shell, an inner die sleeve, and a die core. A cavity is formed inside the outer shell. The inner die sleeve and the die core are respectively placed at opposite ends of the cavity along its axis. A conical melting cavity and a cylindrical shaping cavity are respectively formed at the center of the inner die sleeve. A heat-conducting ring is embedded in the inner wall of the melting cavity. Several heat-conducting blocks are fixedly connected to the outer wall of the heat-conducting ring. One end of each heat-conducting block, away from the heat-conducting ring, penetrates the inner die sleeve and directly contacts the inner wall of the cavity. A heating block is inserted through the outer shell at the position corresponding to the heat-conducting block, and the heating block directly contacts the heat-conducting block. An electric heating sleeve is fitted on the outer side of the outer shell, and the output end of the electric heating sleeve directly contacts the heating block. A cooling ring is embedded in the end of the shaping cavity away from the melting cavity. A spiral circulation pipe is nested in the outer wall of the cooling ring, and the spiral circulation pipe is filled with a recirculating coolant.

[0008] The present invention further explains that the melting cavity is located at one end of the inner mold sleeve near the center of the cavity and is connected to the cavity, the shaping cavity is located at one end of the inner mold sleeve away from the center of the cavity, the shaping cavity is connected to the melting cavity, and the end of the shaping cavity away from the melting cavity opens outward.

[0009] This utility model further describes that the mold core includes a fixed section, an extension section, and a wire exit section in sequence along the axial direction of the cavity. The fixed section is located at the end away from the inner mold sleeve, and the wire exit section is located at the end close to the inner mold sleeve. The fixed section has a cylindrical structure, and the outer circumferential wall of the fixed section fits against the inner wall of the cavity. An inlet cavity is opened in the fixed section, and the inlet cavity is a cylindrical cavity. The extension section has a conical structure, and a bundle-gathering cavity is opened in the extension section, and the bundle-gathering cavity is a conical cavity. The end of the extension section away from the fixed section is located in the melting cavity, and the wire exit section has a cylindrical structure.

[0010] This utility model further explains that the taper of the outer wall of the extension section is smaller than the taper of the inner wall of the melting cavity, one side of the large inner diameter of the bundling cavity is connected to the inlet cavity, and the dimension of the small inner diameter of the bundling cavity is the same as the inner core diameter of the cable to be extruded.

[0011] The present invention further explains that the outer diameter of the lead-out section is smaller than the inner diameter of the shaping cavity, the lead-out section has a lead-out cavity, the lead-out cavity is connected to the bundle cavity, and the inner diameter of the lead-out cavity is the same as the inner diameter of the cable core to be extruded.

[0012] This utility model further illustrates that the outer shell is provided with a feed port, which communicates with the cavity and the output end of the cable extruder. A first annular support and a second annular support are fixedly connected inside the cavity. The first annular support and the second annular support are respectively located at both ends of the feed port along the axis of the cavity. The end face of the die sleeve near the melt cavity along its axis abuts against the end face of the first annular support. The end face of the die core fixing section near the extension section along its axis abuts against the end face of the second annular support.

[0013] This utility model further illustrates that several positioning blocks are fixedly connected to the outer wall of the inner mold sleeve and the outer wall of the fixed section of the mold core. The inner wall of the cavity is provided with positioning grooves corresponding to the positioning blocks, and the positioning blocks cooperate with the positioning grooves.

[0014] The present invention further explains that threaded countersunk holes are provided on both the inner mold sleeve and the mold core fixing section. The threaded countersunk holes and the positioning blocks are staggered in the circumferential direction. A plurality of the threaded countersunk holes are inclined toward the center point of the cavity. The outer shell is provided with threaded through holes corresponding to the threaded countersunk holes. The threaded countersunk holes and the threaded through holes are interconnected and have the same inner diameter. The threaded through holes and the threaded countersunk holes are screwed together with a fixing bolt.

[0015] Compared with the prior art, the beneficial effects achieved by this utility model are as follows: This utility model, by setting up an electric heating jacket, heating block, heat-conducting block and heat-conducting ring to form an auxiliary heating system, maintains a constant temperature for the cable insulation material in the melting cavity, prevents blockage, and improves the production efficiency of overhead cables.

[0016] By setting a cooling ring, a spiral circulation pipe, and an external refrigeration unit in the forming cavity, the extruded cable insulation material is cooled quickly and evenly, which improves the forming speed, ensures uniform insulation layer thickness, and improves the production quality of overhead cables.

[0017] By setting up positioning blocks, positioning grooves, and inclined threaded countersunk holes and bolt combinations, the inner mold sleeve and mold core can be installed quickly and with high precision, circumferentially locked and axially positioned, improving concentricity and compressive strength. Attached Figure Description

[0018] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings:

[0019] Figure 1 This is a schematic diagram of the overall side sectional structure of this utility model;

[0020] Figure 2 This is a cross-sectional view of the overall structure of this utility model from another side (relative). Figure 1 (The cutting position is rotated 90° to perform the cutting).

[0021] In the diagram: 1. Outer shell; 2. Inner mold sleeve; 3. Mold core; 4. Cavity; 5. Melting chamber; 6. Shaping chamber; 7. Fixing section; 8. Extension section; 9. Outlet section; 10. Inlet cavity; 11. Bundling cavity; 12. Outlet cavity; 13. Feed port; 14. First annular support seat; 15. Second annular support seat; 16. Positioning block; 17. Positioning groove; 18. Threaded countersunk hole; 19. Threaded through hole; 20. Heat-conducting ring; 21. Heat-conducting block; 22. Heating block; 23. Electric heating jacket; 24. Cooling ring; 25. Spiral circulation pipe. Detailed Implementation

[0022] The following detailed, non-limiting description of the present invention, in conjunction with preferred embodiments and accompanying drawings, is provided. Obviously, the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0023] Please see Figure 1-2 The present invention provides a technical solution: a mold head for producing pressure-resistant overhead cables, including a shell 1, an inner mold sleeve 2 and a mold core 3. Specifically, the shell 1 is a cylindrical sleeve structure, and a cavity 4 is opened inside the shell 1. The cavity 4 is cylindrical and its two ends are open outward. The inner mold sleeve 2 and the mold core 3 are respectively placed inside the cavity 4 at both ends along its axis.

[0024] The inner mold sleeve 2 has a cylindrical structure. The outer wall of the inner mold sleeve 2 fits against the inner wall of the cavity 4. A melting cavity 5 and a shaping cavity 6 are respectively opened at the center of the inner mold sleeve 2. The melting cavity 5 is located at the end of the inner mold sleeve 2 near the center of the cavity 4 and is connected to the cavity 4. The shaping cavity 6 is located at the end of the inner mold sleeve 2 away from the center of the cavity 4. The shaping cavity 6 is connected to the melting cavity 5, and the end of the shaping cavity 6 away from the melting cavity 5 opens outward.

[0025] The melting cavity 5 is a conical cavity, and the shaping cavity 6 is a cylindrical cavity. The central axes of the melting cavity 5 and the shaping cavity 6 coincide with the central axis of the inner mold sleeve 2.

[0026] The mold core 3 includes a fixed section 7, an extension section 8 and a wire outlet section 9 along the axial direction of the cavity 4. The fixed section 7 is located at the end away from the inner mold sleeve 2, and the wire outlet section 9 is located at the end close to the inner mold sleeve 2.

[0027] The fixed section 7 is a cylindrical structure. The outer circumferential wall of the fixed section 7 fits against the inner wall of the cavity 4. The fixed section 7 has an inlet cavity 10, which is a cylindrical cavity.

[0028] The extension section 8 has a conical structure. The taper of the outer wall of the extension section 8 is smaller than the taper of the inner wall of the melting cavity 5. A bundling cavity 11 is provided in the extension section 8. The bundling cavity 11 is a conical cavity. One side of the large inner diameter of the bundling cavity 11 is connected to the inlet cavity 10. The size of the small inner diameter of the bundling cavity 11 is the same as the diameter of the inner core of the cable to be extruded.

[0029] The end of the extension section 8 away from the fixed section 7 is located in the melting chamber 5. The exit section 9 is a cylindrical structure. The outer diameter of the exit section 9 is smaller than the inner diameter of the shaping chamber 6. The exit section 9 has an exit cavity 12, which is connected to the bundling chamber 11. The inner diameter of the exit cavity 12 is the same as the inner diameter of the cable core to be extruded.

[0030] The outer casing 1 has a feed port 13, which is connected to the cavity 4 and the output end of the cable extruder. The cable extruder is a conventional technology used to output molten cable insulation material and wrap it around the metal core of the cable through the die.

[0031] A first annular support 14 and a second annular support 15 are fixedly connected inside the cavity 4. The first annular support 14 and the second annular support 15 are respectively located at both ends of the feed inlet 13 along the axial direction of the cavity 4.

[0032] Among them, the end face of the inner mold sleeve 2 near the melting cavity 5 along its axial direction abuts against the end face of the first annular support 14, and the end face of the fixed section 7 of the mold core 3 near the extension section 8 along its axial direction abuts against the end face of the second annular support 15.

[0033] The cross-sectional shape of the first annular support 14 and the second annular support 15 is a right trapezoid, so that the inner circumference of the first annular support 14 and the second annular support 15 matches the taper of the inner wall of the melting cavity 5 and the outer wall of the extension section 8, respectively.

[0034] Several positioning blocks 16 are fixedly connected to the outer wall of the inner mold sleeve 2 and the outer wall of the fixed section 7 of the mold core 3. The positioning blocks 16 on the inner mold sleeve 2 are evenly distributed in a circle with the center of the inner mold sleeve 2 as the center. The positioning blocks 16 on the outer wall of the fixed section 7 of the mold core 3 are evenly distributed in a circle with the center of the fixed section 7 as the center. The inner wall of the cavity 4 is provided with positioning grooves 17 corresponding to the positioning blocks 16. The positioning blocks 16 cooperate with the positioning grooves 17 to restrict and fix the inner mold sleeve 2 and the mold core 3 in the circumferential direction in the cavity 4, so as to prevent the inner mold sleeve 2 and the mold core 3 from rotating in the circumferential direction in the cavity 4.

[0035] Both the inner mold sleeve 2 and the mold core 3 fixed section 7 are provided with threaded countersunk holes 18. The threaded countersunk holes 18 and the positioning block 16 are staggered in the circumferential direction. Several threaded countersunk holes 18 are inclined to one side of the center point of the cavity 4. The threaded countersunk holes 18 on the inner mold sleeve 2 and the mold core 3 fixed section 7 are evenly distributed in a circle with their central axis as the center.

[0036] The outer shell 1 has a threaded through hole 19 corresponding to the threaded countersunk hole 18. The threaded countersunk hole 18 and the threaded through hole 19 are interconnected and have the same inner diameter. The threaded through hole 19 and the threaded countersunk hole 18 are screwed together with a fixing bolt. The inner mold sleeve 2 and the mold core 3 are fixed in the cavity 4 by the fixing bolt.

[0037] The outer shell 1, inner mold sleeve 2, and mold core 3 are all made of metal materials with poor thermal conductivity, including but not limited to titanium alloy, chromium alloy, manganese alloy, and low carbon steel.

[0038] A heat-conducting ring 20 is embedded in the inner wall of the melting cavity 5. Several heat-conducting blocks 21 are fixedly connected to the outer wall of the heat-conducting ring 20. One end of the heat-conducting blocks 21 away from the heat-conducting ring 20 passes through the inner mold sleeve 2 and directly contacts the inner wall of the cavity 4. A heating block 22 is inserted through the outer shell 1 at the position corresponding to the heat-conducting block 21. The heating block 22 is in direct contact with the heat-conducting block 21.

[0039] An electric heating sleeve 23 is fitted on the outer side of the outer shell 1. The output end of the electric heating sleeve 23 is in direct contact with the heating block 22, so that the generated heat energy is transferred to the heat-conducting ring 20 through the heating block 22 and the heat-conducting block 21, thereby assisting in heating the cable material in the melting chamber 5 and preventing blockage.

[0040] A cooling ring 24 is embedded at the end of the shaping cavity 6 away from the melting cavity 5. A spiral circulation pipe 25 is nested on the outer wall of the cooling ring 24. The spiral circulation pipe 25 is filled with circulating coolant to achieve heat exchange with the cooling ring 24.

[0041] The heat-conducting ring 20, heat-conducting block 21, heating block 22 and cooling ring 24 are all made of metal materials with good thermal conductivity, including but not limited to copper, aluminum and other metals.

[0042] The input and output ends of the spiral circulation pipe 25 pass through the cooling ring 24 and are connected to a refrigeration unit. The input and output ends of the spiral circulation pipe 25 are connected to the output and input ends of the refrigeration unit, respectively, so that the refrigeration unit can realize the cooling circulation of the coolant in the spiral circulation pipe 25.

[0043] In this embodiment, the multiple metal cores of the overhead cable pass through the inlet cavity 10, the bundle cavity 11 and the outlet cavity 12 in sequence, and then exit from the mold core 3 and enter the melting cavity 5.

[0044] At the same time, the motor extruder feeds the molten cable insulation material into the melting chamber 5 through the feed port. When the cable metal core passes through the melting chamber 5, it is wrapped by the molten cable insulation material in the melting chamber 5 and then enters the shaping chamber 6 together.

[0045] During the process of passing through the shaping cavity 6, the cooling ring 24 inside the shaping cavity 6 absorbs heat. At the same time, the refrigerator circulates and cools the coolant in the spiral circulation pipe 25. Then, the coolant in the spiral circulation pipe 25 exchanges heat with the cooling ring 24, thereby achieving continuous cooling of the cooling ring 24. Under the cooling action of the cooling ring 24, the molten cable insulation material completes solidification and shaping, and is extruded from one end of the shaping cavity 6 into the inner mold sleeve 2.

[0046] During the cable production process, heating can be achieved through the electric heating jacket 23, and heat transfer can be achieved through the heating block 22 and the heat-conducting block 21 to the heat-conducting ring 20 to assist in heating the cable insulation material in the melting chamber 5, preventing it from cooling down and solidifying, causing blockage and affecting the cable production efficiency.

[0047] Meanwhile, the continuous cooling of the cable by the cooling ring 24 can improve the efficiency of cable extrusion and shaping, and prevent the cable insulation material in the molten cavity 5 from being blocked due to low shaping efficiency.

[0048] In the description of this utility model, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and do not 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 utility model.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A die head for producing pressure-resistant overhead cables, characterized in that: The device includes an outer shell (1), an inner mold sleeve (2), and a mold core (3). A cavity (4) is formed inside the outer shell (1). The inner mold sleeve (2) and the mold core (3) are respectively placed at opposite ends of the cavity (4) along its axis. A conical melting cavity (5) and a cylindrical shaping cavity (6) are respectively formed at the center of the inner mold sleeve (2). A heat-conducting ring (20) is embedded in the inner wall of the melting cavity (5). Several heat-conducting blocks (21) are fixedly connected to the outer wall of the heat-conducting ring (20). One end of each heat-conducting block (21) away from the heat-conducting ring (20) penetrates the inner mold sleeve (2) and... The inner wall of the cavity (4) is in direct contact with the outer shell (1). A heating block (22) is inserted through the outer shell (1) at the position corresponding to the heat-conducting block (21). The heating block (22) is in direct contact with the heat-conducting block (21). An electric heating sleeve (23) is fitted on the outer side of the outer shell (1). The output end of the electric heating sleeve (23) is in direct contact with the heating block (22). A cooling ring (24) is embedded at the end of the shaping cavity (6) away from the melting cavity (5). A spiral circulation pipe (25) is nested on the outer wall of the cooling ring (24). The spiral circulation pipe (25) is filled with a recirculating coolant.

2. The die head for producing a pressure-resistant overhead cable according to claim 1, characterized in that: The melting cavity (5) is located at one end of the inner mold sleeve (2) near the center of the cavity (4) and is connected to the cavity (4). The shaping cavity (6) is located at one end of the inner mold sleeve (2) away from the center of the cavity (4). The shaping cavity (6) is connected to the melting cavity (5). The end of the shaping cavity (6) away from the melting cavity (5) opens outward.

3. The die head for producing a pressure-resistant overhead cable according to claim 2, characterized in that: The mold core (3) includes a fixed section (7), an extension section (8), and a wire exit section (9) in sequence along the axial direction of the cavity (4). The fixed section (7) is located at the end away from the inner mold sleeve (2), and the wire exit section (9) is located at the end close to the inner mold sleeve (2). The fixed section (7) is a cylindrical structure, and the outer circumferential wall of the fixed section (7) is in contact with the inner wall of the cavity (4). The fixed section (7) has an inlet cavity (10), which is a cylindrical cavity. The extension section (8) is a conical structure, and the extension section (8) has a bundle cavity (11), which is a conical cavity. The end of the extension section (8) away from the fixed section (7) is located in the melting cavity (5). The wire exit section (9) is a cylindrical structure.

4. The die head for producing a pressure-resistant overhead cable according to claim 3, characterized in that: The taper of the outer wall of the extension section (8) is smaller than the taper of the inner wall of the melting cavity (5). One side of the large inner diameter of the bundling cavity (11) is connected to the inlet cavity (10). The size of one side of the small inner diameter of the bundling cavity (11) is the same as the diameter of the inner core of the cable to be extruded.

5. The die head for producing a pressure-resistant overhead cable according to claim 4, characterized in that: The outer diameter of the cable outlet section (9) is smaller than the inner diameter of the shaping cavity (6). The cable outlet section (9) has a cable outlet cavity (12). The cable outlet cavity (12) is connected to the bundle cavity (11). The inner diameter of the cable outlet cavity (12) is the same as the inner diameter of the cable core to be extruded.

6. The die head for producing a pressure-resistant overhead cable according to claim 5, characterized in that: The outer shell (1) is provided with a feed port (13), which is connected to the cavity (4) and the output end of the cable extruder. The cavity (4) is fixedly connected with a first annular support (14) and a second annular support (15). The first annular support (14) and the second annular support (15) are respectively located at both ends of the feed port (13) along the axial direction of the cavity (4). The end face of the mold sleeve (2) near the melt cavity (5) along its axial direction abuts against the end face of the first annular support (14). The end face of the fixed section (7) of the mold core (3) near the extension section (8) along its axial direction abuts against the end face of the second annular support (15).

7. The die head for producing a pressure-resistant overhead cable according to claim 6, characterized in that: The outer wall of the inner mold sleeve (2) and the outer wall of the fixed section (7) of the mold core (3) are both fixedly connected with a number of positioning blocks (16). The inner wall of the cavity (4) is provided with positioning grooves (17) corresponding to the positioning blocks (16). The positioning blocks (16) and positioning grooves (17) cooperate with each other.

8. The die head for producing a pressure-resistant overhead cable according to claim 7, characterized in that: The inner mold sleeve (2) and the mold core (3) are both provided with threaded countersunk holes (18). The threaded countersunk holes (18) and the positioning blocks (16) are staggered in the circumferential direction. Several of the threaded countersunk holes (18) are inclined to one side of the center point of the cavity (4). The outer shell (1) is provided with threaded through holes (19) corresponding to the threaded countersunk holes (18). The threaded countersunk holes (18) and the threaded through holes (19) are interconnected and have the same inner diameter. The threaded through holes (19) and the threaded countersunk holes (18) are screwed together with fixing bolts.

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