A device and process for dry crosslinking wire conductor core preheating

Abstract

The application relates to a dry crosslinking wire conductor core preheating device and process, which comprises a drying bin, a heating bin and a heat preservation bin arranged in sequence along a set direction and communicated with each other, and a heat source assembly for providing heat sources for the drying bin, the heating bin and the heat preservation bin; the heat source assembly comprises a heater and an air guide device, the heater is arranged in the heating bin and used for heating the conductor core; the air guide device is installed in the heating bin and used for introducing air into the heating bin to exchange heat with the heater, and the air after heat exchange is correspondingly delivered to the heating bin and the heat preservation bin; the application can effectively improve the temperature uniformity of the conductor core preheating, reduce heat loss and effectively improve the heating efficiency.

Description

Technical Field

[0001] This invention relates to the field of cable manufacturing technology, and more specifically, to a device and process for preheating the conductor core of dry cross-linked cables. Background Technology

[0002] Dry crosslinking production lines are mainly used to produce crosslinked polyethylene (XLPE) insulated cables. The core of the process is to form a crosslinked structure between polyethylene molecular chains through chemical or physical methods, thereby improving the material's heat resistance, mechanical strength, and electrical properties. In dry crosslinking production lines, conductor core preheating is a key process step, mainly used for temperature control of the conductor core before extruding the insulation layer. This step can significantly improve the extrusion quality of the insulation layer, reduce thermal stress, and optimize the uniformity of the crosslinking reaction.

[0003] There are three main existing methods for preheating conductor cores:

[0004] (1) Induction heating utilizes electromagnetic induction to generate eddy currents in the core (usually copper or aluminum conductors) to generate heat. This method has the advantages of fast heating speed (up to 200~300℃ / second), no impact on surrounding equipment, and high temperature control accuracy (±1℃). However, it also has the disadvantage of uneven heating of large cross-section conductors (such as the skin effect leading to a lower center temperature). At the same time, during the induction heating process, the induction coil itself will also generate a lot of heat, which requires a separate cooling device (such as a water cooler or air cooler) to control the coil temperature. This not only increases the operating cost but also wastes heat.

[0005] (2) Hot air heating: The conductor is heated by directly blowing a high-temperature airflow (usually 80~120℃) onto the conductor surface. This method has simple equipment and low cost; however, the heating efficiency is low and the temperature uniformity is poor, so it is more suitable for small cross-section or multi-core cables.

[0006] (3) Infrared heating, which heats the conductor by directly applying infrared radiation to the conductor surface; this heating method is non-contact heating and is suitable for applications requiring high surface cleanliness. It is sensitive to the reflectivity of the conductor surface (e.g., parameters need to be adjusted for aluminum conductors).

[0007] Furthermore, induction heating requires a high-power power supply, while hot air heating results in significant heat loss, leading to increased production costs. Additionally, if the preheated conductor fails to enter the extruder immediately, heat loss will also cause uneven temperature distribution, all of which will affect the final product quality and the production efficiency of the dry crosslinking production line.

[0008] To address the aforementioned issues, existing technologies urgently need improvement. Summary of the Invention

[0009] In view of this, the present invention provides a device and process for preheating conductor cores of dry cross-linked wires, which can effectively improve the temperature uniformity of conductor core preheating, reduce heat loss, and effectively improve heating efficiency.

[0010] The present invention specifically discloses a preheating device for dry cross-linked wire conductor core, comprising a drying chamber, a heating chamber and a heat preservation chamber arranged sequentially and interconnected along a set direction, and a heat source assembly for providing heat source to the drying chamber, the heating chamber and the heat preservation chamber;

[0011] The heat source components include a heater and an exhaust fan. The heater is installed in the heating chamber to heat the conductor core. The exhaust fan is installed in the heating chamber to introduce air into the heating chamber for heat exchange with the heater, and then delivers the heat-exchanged air to the heating chamber and the insulation chamber respectively.

[0012] Furthermore, the heater is an induction heater, which includes a heating coil for heating and a heating power supply for supplying power to the heating coil. There are multiple heaters, and the heating coils corresponding to each heater are arranged sequentially in a set direction within the heating chamber. The current frequencies of the heating power supplies of any two adjacent heaters are different.

[0013] Furthermore, along the set direction, the current frequency of the heating power supply of multiple heaters decreases step by step.

[0014] Furthermore, the heating chamber includes a shell, a conduit, and a partition plate. The conduit is disposed inside the shell, and the heating coil is wound around the conduit and located inside the shell. The partition plate is disposed between the shell and the heating coil, and the partition plate divides the radial gap between the shell and the heating coil into a first heat exchange chamber and a second heat exchange chamber. The first heat exchange chamber is connected to the drying chamber, and the second heat exchange chamber is connected to the insulation chamber.

[0015] Furthermore, it also includes a first buffer compartment and a second buffer compartment;

[0016] The first buffer chamber is located between the drying chamber and the heating chamber. The first buffer chamber has an inlet chamber, a first heat exchange post chamber and a second heat exchange pre chamber. The inlet chamber connects the drying chamber to the conduit. The first heat exchange chamber is connected to the drying chamber through the first heat exchange post chamber. The second heat exchange pre chamber is connected to the second heat exchange chamber. The second heat exchange pre chamber is also provided with an insulated air inlet channel for air to enter.

[0017] The second buffer chamber is located between the heating chamber and the insulation chamber; the second buffer chamber has a cable outlet chamber, a first heat exchange pre-chamber chamber and a second heat exchange post-chamber chamber. The cable outlet chamber connects the cable pipe to the insulation chamber. The first heat exchange pre-chamber is connected to the first heat exchange chamber. The first heat exchange pre-chamber is also provided with a drying air inlet channel for air to enter. The second heat exchange chamber is connected to the insulation chamber through the second heat exchange post-chamber chamber.

[0018] Furthermore, multiple guide vanes are provided in both the first and second heat exchange chambers. The guide vanes have a semi-circular annular structure and multiple holes for air to flow through. Each guide vane is inclined in the axial direction, and the inclination directions of adjacent guide vanes are opposite.

[0019] Furthermore, the heat source components also include auxiliary heaters and temperature sensors. Auxiliary heaters are installed in both the drying chamber and the insulation chamber, and temperature sensors are installed in the drying chamber, the housing, the conduit, and the insulation chamber.

[0020] Furthermore, the heating chamber also includes end caps for sealing the shell. The shell is a hollow cylindrical structure arranged in a set direction. End caps are installed at both ends of the shell. The end caps have a first through hole at the position corresponding to the first heat exchange chamber and a second through hole at the position corresponding to the second heat exchange chamber. The blower is installed on the end cap at the position corresponding to the first and second through holes.

[0021] Furthermore, it also includes an exhaust fan, the drying chamber is equipped with a drying exhaust channel for discharging air from the drying chamber, the insulation chamber is equipped with an insulation exhaust channel for discharging air from the insulation chamber, and both the drying exhaust channel and the insulation exhaust channel are equipped with exhaust fans.

[0022] This invention also discloses a preheating process for dry cross-linked wire conductor cores. This process is based on the aforementioned preheating device for dry cross-linked wire conductor cores and specifically includes the following steps:

[0023] S1. Start the auxiliary heaters in the drying chamber and the insulation chamber. When the ambient temperature in the drying chamber reaches the set temperature I and the ambient temperature in the insulation chamber reaches the set temperature II, start the heaters.

[0024] S2. Control the conductor core to pass through the drying chamber, heating chamber and heat preservation chamber sequentially at a set speed;

[0025] S3. When the temperature of the heating coil of the heater itself rises to the set temperature III, turn on the induced draft fan and exhaust fan, and gradually reduce the heating power of the auxiliary heater until the auxiliary heater is turned off;

[0026] S4. Adjust the power of the induced draft fan and the exhaust fan to maintain the ambient temperature in the drying chamber at the set temperature I and the ambient temperature in the insulation chamber at the set temperature II.

[0027] The beneficial effects of this invention are:

[0028] This invention discloses a preheating device and process for dry cross-linked conductor cores. The heating device comprises a drying chamber, a heating chamber, and a heat preservation chamber. The main heat source for all three chambers is the heater in the heating chamber, which directly heats the conductor core to achieve preheating before dry cross-linking. Simultaneously, the drying chamber pre-dries the conductor core before heating to remove moisture from its surface, preventing uneven temperature distribution caused by direct heating and providing a preheating effect, making the heating of the conductor core faster and more efficient after entering the heating chamber. The heat preservation chamber ensures that the conductor core is not directly exposed to air after heating, preventing uneven temperature distribution due to heat loss. This invention effectively improves the temperature uniformity of conductor core preheating, reduces heat loss, and significantly enhances heating efficiency. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the structure of the present invention;

[0030] Figure 2 This is the front view of the present invention;

[0031] Figure 3 This is a front structural cross-sectional view of the present invention;

[0032] Figure 4 for Figure 2 Sectional view at point AA;

[0033] Figure 5 This is an exploded structural diagram of the first buffer chamber, the heat chamber, the heat source assembly, and the second buffer chamber.

[0034] Figure 6 This is a schematic diagram of the assembly structure of the first buffer chamber, the heat chamber, the heat source assembly, and the second buffer chamber.

[0035] Figure 7 for Figure 6 Sectional view at point BB;

[0036] Figure 8 This is a schematic diagram of the arrangement structure of the guide vane in this invention;

[0037] Reference numerals: Drying chamber 1, Drying exhaust channel 101, Viewing window 102, Heating chamber 2, Insulation chamber 3, Insulation exhaust channel 301, First buffer chamber 4, Second heat exchange front chamber 401, First heat exchange rear chamber 402, Inlet chamber 403, Insulation air inlet channel 404, Second buffer chamber 5, Second heat exchange rear chamber 501, First heat exchange front chamber 502, Outlet chamber 503, Drying air inlet channel 504, Heating coil 6, Conduit 7, Heating power supply 8, Middle partition 9, Auxiliary heater 10, Housing 11, Protective plate 12, End cap 13, Second through hole 1301, First through hole 1302, Exhaust fan 14, Exhaust fan 15, Guide plate 16. Detailed Implementation

[0038] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below.

[0039] It should be noted that in the description of this specification, the terms "upper", "lower", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", 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 the present invention and simplifying the description, 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 limiting the present invention.

[0040] As shown in the figure, an embodiment of the present invention specifically discloses a preheating device for dry cross-linked wire conductor cores, including a drying chamber 1, a heating chamber 2, and a heat preservation chamber 3 arranged sequentially and interconnected along a set direction, and a heat source assembly for providing heat to the drying chamber 1, the heating chamber 2, and the heat preservation chamber 3; the heat source assembly includes a heater and a blower 14, the heater being disposed in the heating chamber 2 for heating the conductor core; the blower 14 being installed in the heating chamber 2 for introducing air into the heating chamber 2 for heat exchange with the heater, and delivering the heat-exchanged air to the heating chamber 2 and the heat preservation chamber 3 respectively. In this embodiment, air is introduced using a draft fan 14 to exchange heat with the heater, thereby generating hot air as the heat source for the drying chamber 1 and the insulation chamber 3. The drying chamber 1 can pre-dry the conductor wire and has a certain heating effect, avoiding uneven temperature distribution during the heating process caused by the surface moisture of the conductor wire core. The insulation chamber 3 prevents the heated conductor wire core from directly contacting the outside cold air. In actual production, the inlet of subsequent processing steps (such as the inlet of the extruder) can be connected to the insulation chamber 3. This allows the entire preheating process of the conductor wire core to utilize a composite heat source, coupling the hot air circulation system with the heating device. Forced convection improves energy utilization and effectively enhances heat exchange efficiency, establishing a multi-stage temperature compensation mechanism. In this embodiment, the draft fan 14 can be selected from various types of fans or industrial fans, preferably a fan. The set direction is the delivery direction during conductor wire core processing. In this embodiment, different gases can be selected as heat exchange media instead of air for conductor wire cores of different materials to avoid oxidation. This is understandable to those skilled in the art and will not be elaborated here.

[0041] In this embodiment, the heater is an induction heater, which includes a heating coil 6 for heating and a heating power supply 8 for supplying power to the heating coil 6. Multiple heaters are provided, and the heating coils 6 corresponding to each heater are arranged sequentially along a predetermined direction within the heating chamber 2. The current frequencies of the heating power supplies 8 for any two adjacent heaters are different. In this embodiment, the current frequencies of the heating power supplies 8 for the multiple heaters decrease progressively along the predetermined direction. The heater in this embodiment is the core area for implementing the conductor core heating process. Specific devices of different forms can be used as heaters depending on the actual situation. In this embodiment, an induction heater is preferred, and it is combined with a forced convection heat exchange system. The introduced air-cooled air not only removes the heat generated by the heating coil 6 during operation, ensuring its normal operation, but also the hot air formed after heat exchange serves as a heat source for the drying chamber 1 and the insulation chamber 3, effectively improving energy utilization. Multiple sets of heating coils 6 with different current frequencies are arranged inside the heating chamber 2. Their function is to generate a deep-penetrating eddy current effect through electromagnetic induction, overcoming the temperature gradient problem of the conductor cross-section caused by the skin effect. This invention constructs a synergistic mechanism between a three-level gradient temperature control structure and a hot air circulation system. Through a continuous process path of pretreatment in drying chamber 1, main heating in heating chamber 2, and constant temperature maintenance in insulation chamber 3, combined with a heat redistribution system driven by induced draft fan 14, it not only solves the problem of temperature decay after traditional single-stage heating, but also realizes the synergistic utilization of heat energy between different chambers, thereby improving heating uniformity while reducing overall energy consumption. In this embodiment, multiple heaters are provided, and each heater has a different power supply frequency. The heating power supply 8 in this embodiment is used to provide high-frequency AC power (1-100kHz), including components such as a high-frequency inverter (IGBT or MOSFET), a resonant capacitor, and a control system. Different power supply frequencies of induction heaters will result in different heating effects. For example, high-frequency induction heating (10-100kHz) has a fast heating speed and a significant skin effect (suitable for surface heating); low-frequency induction heating (1-10kHz) takes into account both penetration depth and heating speed. In this embodiment, three sets of heaters are provided, with power supply frequencies designed to be 30Hz, 10kHz, and 3kHz, respectively. Of course, those skilled in the art can make corresponding adjustments according to the material and diameter of the conductor core. This embodiment adopts this progressively decreasing frequency configuration so that the high-frequency current preferentially heats the conductor surface, while the low-frequency current enhances the penetration into the internal region of the conductor; it optimizes the heating uniformity of the conductor core; and ensures that the conductor is processed in segments at different heating stages, forming a progressive heating process. Adjacent heaters use power supplies with different current frequencies. By adjusting the current frequency, the skin depth is changed. High-frequency current heats the surface of the conductor, while low-frequency current enhances penetration into the internal region of the conductor, thereby weakening the limitations of the skin effect caused by a single frequency.This multi-frequency combined heating method covers different depths of the conductor core, ultimately achieving a uniform temperature gradient from the surface to the core region, thus solving the problem of uneven heating of large-section conductors. In this embodiment, a viewing window 102 is also provided in the drying chamber to facilitate observation of the conductor core's condition and whether it has correctly entered the heating chamber. While auxiliary devices such as conductor conveying devices are not specifically described in this embodiment, those skilled in the art can easily install appropriate auxiliary devices in suitable locations based on this embodiment to ensure the smooth progress of the preheating process.

[0042] In this embodiment, the heating chamber 2 includes a shell 11, a conduit 7, and a partition 9. The conduit 7 is disposed inside the shell 11, and the heating coil 6 is wound around the conduit 7 and located inside the shell 11. The partition 9 is disposed between the shell 11 and the heating coil 6, and the partition 9 divides the radial gap between the shell 11 and the heating coil 6 into a first heat exchange chamber and a second heat exchange chamber. The first heat exchange chamber is connected to the drying chamber 1, and the second heat exchange chamber is connected to the insulation chamber 3. As shown in the figure, in this embodiment, the conduit 7 is used to separate the conductor core from the heating coil 6 to prevent outside air from entering and affecting the temperature of the conductor core, while ensuring sufficient heat exchange between the air and the heating coil 6. In this embodiment, the partition 9 is two separate pieces, symmetrically arranged along the radial direction of the shell 11. The partition 9 divides the radial gap between the shell 11 and the heating coil 6 into a first heat exchange chamber and a second heat exchange chamber. There are several ways to fix the conduit in this embodiment, such as fixing it to the housing by a bracket. In this embodiment, a protective plate 12 is also provided on the outer surface of the housing. The wire harness of the heating coil needs to pass through the housing to connect to the heating power supply. The protective plate is provided to prevent the wire harness from being directly exposed during operation, thereby improving production safety.

[0043] In this embodiment, a first buffer chamber 4 and a second buffer chamber 5 are also included. The first buffer chamber 4 is located between the drying chamber 1 and the heating chamber 2. The second buffer chamber 5 is located between the heating chamber 2 and the heat preservation chamber 3. The first buffer chamber 4 and the second buffer chamber 5 are provided to buffer the air entering and leaving the heating chamber 2, so that the air flows more evenly and stably.

[0044] As shown in the figure, the first buffer chamber 4 has an inlet cavity 403, a first post-heat exchange cavity 402, and a second pre-heat exchange cavity 401. The inlet cavity 403 connects the drying chamber 1 to the conduit 7. The first heat exchange cavity is connected to the drying chamber 1 through the first post-heat exchange cavity 402. The second pre-heat exchange cavity 401 is connected to the second heat exchange cavity. The second pre-heat exchange cavity 401 is also provided with a heat-insulating air inlet channel 404 for air entry. The second buffer chamber 5 has an outlet cavity 503, a first pre-heat exchange cavity 502, and a second post-heat exchange cavity 501. The outlet cavity 503 connects the conduit 7 to the heat-insulating chamber 3. The first pre-heat exchange cavity 502 is connected to the first heat exchange cavity. The first pre-heat exchange cavity 502 is also provided with a drying air inlet channel 504 for air entry. The second heat exchange cavity is connected to the heat-insulating chamber 3 through the second post-heat exchange cavity 501. This application achieves effective buffering and mixing of hot air between the drying chamber 1, the heating chamber 2, and the heat-insulating chamber 3, thereby improving heat exchange efficiency. Meanwhile, the conductor core is transported within a closed channel, reducing heat loss. Furthermore, the zoned airflow helps maintain temperature uniformity within drying chamber 1 and insulation chamber 3, improving the overall preheating effect.

[0045] In this embodiment, multiple guide plates 16 are provided in both the first heat exchange cavity and the second heat exchange cavity. The guide plate 16 has a semi-circular ring structure and multiple holes for air to flow through. Each guide plate 16 is inclined in the axial direction and the inclination directions of adjacent guide plates 16 are opposite. In this embodiment, the guide plate 16 is attached to the inner wall of the heating chamber at one end in the radial direction and to the surface of the heating coil at the other end. The guide plate 16 divides both the first and second heat exchange chambers into multiple independent small chambers, and each small chamber is connected to the others through holes on the guide plate 16. In the axial direction, the guide plate 16 is also inclined, and in the same chamber, the inclination directions of adjacent guide plates 16 are opposite. This arrangement allows the air entering the first or second heat exchange chamber to be guided and diverted by the guide plate 16. Some of the air directly enters the next small chamber through the holes, while the remaining air is blown towards the surface of the induction coil along the inclination direction of the guide plate 16 for deep convection heat exchange before entering the next chamber. With this design, the air stays in the heating chamber for a longer time and the flow is more targeted, which makes the heat exchange effect better. Furthermore, the guide plates 16 corresponding to the first and second heat exchange chambers are inclined in opposite directions. That is, if the first heat exchange chamber is arranged in a "W" shape, then the guide plates 16 in the second heat exchange chamber are arranged in an "M" shape. This design makes the gas medium flow direction in the two heat exchange chambers completely opposite, with the inlet and outlet directions being opposite and the guiding directions being opposite. This makes the heat exchange of the coil more complete, which is more conducive to the cooling of the inductive coil and the recovery and reuse of the heat of the induction coil, effectively reducing production costs and improving economic efficiency.

[0046] In this embodiment, the heat source assembly also includes auxiliary heaters 10 and temperature sensors. Auxiliary heaters 10 are installed in both the drying chamber 1 and the insulation chamber 3, and temperature sensors are installed in the drying chamber 1, the housing 11, the conduit 7, and the insulation chamber 3. In this embodiment, auxiliary heaters 10 are also installed in the heating chamber 2 and the insulation chamber 3 to provide a heat source during the initial startup of the equipment, enabling the drying chamber 1 and the insulation chamber 3 to meet operating conditions. They also supplement the insufficient main heat source, accelerating the initial heating rate and allowing the drying chamber 1 and the insulation chamber 3 to quickly enter the working state. The auxiliary heaters 10 can be resistance heating wires or heating plates, with a power range of 500W to 2000W. The temperature sensors can be thermocouples or thermistors, with a temperature measurement range of 0℃ to 300℃. Two to four auxiliary heaters 10 are installed in each of the drying chamber 1 and the insulation chamber 3, evenly distributed on the inner wall of the chamber. Three to five temperature sensors are installed in each of the drying chamber 1 and the insulation chamber 3, distributed in the upper, middle, and lower parts of the chamber. Two to four temperature sensors are evenly distributed along the axial direction on the inner surface of the housing 11. Two to three temperature sensors are evenly distributed along the axial direction on the inner wall of the conduit 7. The auxiliary heater 10 and the temperature sensors are connected to a control system to achieve closed-loop temperature control.

[0047] In this embodiment, the heating chamber 2 further includes an end cap 13 for sealing the housing 11. The housing 11 is a hollow cylindrical structure arranged in a predetermined direction. End caps 13 are installed at both ends of the housing 11. The end caps 13 have a first through hole corresponding to the position of the first heat exchange chamber, and a second through hole corresponding to the position of the second heat exchange chamber. The blower 14 is installed on the end caps 13 corresponding to the positions of the first and second through holes. In this embodiment, the first and second heat exchange chambers are separated by partition plates to form a bidirectional 6-channel structure. The end caps 13 have three first through holes and three second through holes. To reduce manufacturing costs, the blower 14 is only installed at one end of the first and second heat exchange chambers, or it can be installed on both sides simultaneously. This is a choice that those skilled in the art can make based on actual conditions, and will not be elaborated here.

[0048] In this embodiment, an exhaust fan 15 is also included. The drying chamber 1 is provided with a drying exhaust channel 101 for discharging air from the drying chamber 1, and the insulation chamber 3 is provided with an insulation exhaust channel 301 for discharging air from the insulation chamber 3. Both the drying exhaust channel 101 and the insulation exhaust channel 301 are equipped with exhaust fans 15. As shown in the figure, in order to improve the heat convection efficiency and ensure the pressure of each chamber is stable, the exhaust fan 15 shown in the figure is also provided in this embodiment. The start and stop conditions of the exhaust fan 15 should be coupled with the temperature and pressure of the corresponding chamber. That is, when the temperature of the corresponding chamber is too low, the exhaust fan 15 needs to be stopped to reduce heat loss, and the auxiliary heater 10 is turned on for heat compensation. This is something that those skilled in the art can understand and will not be elaborated here.

[0049] Embodiments of the present invention also disclose a preheating process for dry cross-linked wire conductor cores. This process is based on the aforementioned preheating device for dry cross-linked wire conductor cores and specifically includes the following steps:

[0050] S1. Start the auxiliary heaters 10 in the drying chamber 1 and the insulation chamber 3. When the ambient temperature in the drying chamber 1 reaches the set temperature I and the ambient temperature in the insulation chamber 3 reaches the set temperature II, start the heaters. In this embodiment, the set temperature I and the set temperature II are generally between 70 and 120°C (adjusted according to the conductor material, cross-section and production line speed). For example, copper conductors are generally selected at 80 to 100°C, and aluminum conductors are generally selected at 60 to 80°C (to avoid oxidation). The specific temperature parameters can be set by those skilled in the art, and will not be elaborated here.

[0051] S2. Control the conductor core to pass through the drying chamber 1, heating chamber 2 and heat preservation chamber 3 in sequence at a set speed; the set speed needs to be adjusted according to the parameters of each link of the production line, and the highest economic efficiency is preferred while ensuring product quality.

[0052] S3. When the temperature of the heating coil 6 of the heater to be heated reaches the set temperature III, the induced draft fan 14 and the exhaust fan 15 are turned on, and the heating power of the auxiliary heater 10 is gradually reduced until the auxiliary heater 10 is turned off. In this embodiment, the set temperature III depends on the heating coil 6 itself. Under different materials, different diameters and different power frequencies, the normal operating temperature range of the heating coil 6 is different. The set temperature III is based on its normal operating temperature range, which can be understood by those skilled in the art and will not be elaborated here.

[0053] S4. Adjust the power of the induced draft fan 14 and the exhaust fan 15 so that the ambient temperature in the drying chamber 1 is maintained at the set temperature I, and the ambient temperature in the insulation chamber 3 is maintained at the set temperature II.

[0054] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A device for preheating the conductor core of dry cross-linked wire, characterized in that: It includes a drying chamber, a heating chamber, and a heat preservation chamber that are arranged sequentially and interconnected along a set direction, as well as a heat source component for providing heat to the drying chamber, the heating chamber, and the heat preservation chamber; The heat source assembly includes a heater and a fan. The heater is disposed in the heating chamber for heating the conductor core. The fan is installed in the heating chamber for introducing air into the heating chamber to exchange heat with the heater, and then delivering the heat-exchanged air to the heating chamber and the insulation chamber respectively. The heater is an induction heater, which includes a heating coil for heating and a heating power supply for supplying power to the heating coil. There are multiple heaters, and the heating coils corresponding to each of the multiple heaters are arranged sequentially in the heating chamber along a set direction. The current frequencies of the heating power supplies of any two adjacent heaters are different, and along the set direction, the current frequencies of the heating power supplies of the multiple heaters decrease step by step. The heating chamber includes a shell, a conduit, and a partition plate. The conduit is disposed inside the shell, and the heating coil is wound around the conduit and located inside the shell. The partition plate is disposed between the shell and the heating coil, and the partition plate divides the radial gap between the shell and the heating coil into a first heat exchange chamber and a second heat exchange chamber. The first heat exchange chamber is connected to the drying chamber, and the second heat exchange chamber is connected to the insulation chamber. The heat source assembly also includes an auxiliary heater and a temperature sensor. An auxiliary heater is installed in both the drying chamber and the insulation chamber. A temperature sensor is installed in the drying chamber, the shell, the conduit, and the insulation chamber. The heating chamber also includes an end cap for sealing the shell. The shell is a hollow cylindrical structure arranged in a set direction. End caps are installed at both ends of the shell. The end caps have a first through hole at the position corresponding to the first heat exchange chamber. The end caps also have a second through hole at the position corresponding to the second heat exchange chamber. The fan is installed on the end cap at the position corresponding to the first through hole and the second through hole. It also includes an exhaust fan. The drying chamber is provided with a drying exhaust channel for discharging air from the drying chamber, and the insulation chamber is provided with an insulation exhaust channel for discharging air from the insulation chamber. Both the drying exhaust channel and the insulation exhaust channel are equipped with exhaust fans.

2. The device for preheating the conductor core of a dry cross-linked wire according to claim 1, characterized in that: It also includes a first buffer compartment and a second buffer compartment; The first buffer chamber is located between the drying chamber and the heating chamber; the first buffer chamber has an inlet chamber, a first post-heat exchange chamber and a second pre-heat exchange chamber, the inlet chamber connects the drying chamber to the conduit, the first heat exchange chamber is connected to the drying chamber through the first post-heat exchange chamber, the second pre-heat exchange chamber is connected to the second heat exchange chamber, and the second pre-heat exchange chamber is also provided with a heat-insulating air inlet channel for air to enter; The second buffer chamber is located between the heating chamber and the insulation chamber; the second buffer chamber has a cable outlet chamber, a first pre-heat exchange chamber and a second post-heat exchange chamber, the cable outlet chamber connects the cable conduit to the insulation chamber, the first pre-heat exchange chamber connects to the first heat exchange chamber, and the first pre-heat exchange chamber is also provided with a drying air inlet channel for air to enter; the second heat exchange chamber connects to the insulation chamber through the second post-heat exchange chamber.

3. The device for preheating the conductor core of a dry cross-linked wire according to claim 2, characterized in that: Multiple guide plates are provided in both the first and second heat exchange chambers. The guide plates are semi-circular ring structures with multiple holes for air to flow through. Each guide plate is inclined in the axial direction, and the inclination directions of adjacent guide plates are opposite.

4. A preheating process for dry cross-linked wire conductor cores, characterized in that: This process, based on the preheating device for dry cross-linked wire conductor cores as described in any one of claims 1-3, specifically includes the following steps: S1. Start the auxiliary heaters in the drying chamber and the insulation chamber. When the ambient temperature in the drying chamber reaches the set temperature I and the ambient temperature in the insulation chamber reaches the set temperature II, start the heaters. S2. Control the conductor core to pass through the drying chamber, heating chamber and heat preservation chamber sequentially at a set speed; S3. When the temperature of the heating coil of the heater itself rises to the set temperature III, turn on the induced draft fan and the exhaust fan, and gradually reduce the heating power of the auxiliary heater until the auxiliary heater is turned off; S4. Adjust the power of the induced draft fan and the exhaust fan so that the ambient temperature in the drying chamber is maintained at the set temperature I, and the ambient temperature in the insulation chamber is maintained at the set temperature II.

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