Physical foaming extrusion process for Teflon

Abstract

The invention relates to the technical field of cable manufacturing, in particular to a teflon physical foaming extrusion process. The process comprises the steps of wire rod pretreatment, wire rod extrusion molding, wire rod post-treatment and quality detection, wire rod rolling and the like. Wherein in the wire pretreatment, the diameter of a wire is tested by an outer diameter measuring instrument and preheating is performed; in the wire extrusion molding process, an extruder comprising a machine head trolley, a main machine, an auxiliary machine and a nitrogen injection device is used, it is ensured that a plastic material is kept at a proper temperature during melting and extrusion, and nitrogen is injected to prevent oxidation; the post-processing and quality detection of the wire rod comprises core shift detection, multi-stage cooling and comprehensive quality detection; and finally, winding of the wire is completed through the guide device and the take-up device. The cable production efficiency is improved, and the technical effects of product consistency and reliability are ensured.

Description

Technical Field

[0001] The present application relates to the technical field of cable manufacturing, and in particular to a PTFE physical foaming extrusion process. Background Art

[0002] At present, in high-end fields such as modern communication, navigation, electronic countermeasure, and measurement and control equipment, the stable transmission of radio frequency signals is crucial. To meet this requirement, the selection of cable materials and their manufacturing processes are continuously optimized. PTFE (polytetrafluoroethylene) has become an ideal material for the insulation layer of radio frequency cables due to its wide operating temperature range, high operating frequency, low attenuation, small standing wave ratio, good shielding performance, and excellent bending performance. Especially in extreme environments such as rockets and satellites, PTFE cables are more widely used.

[0003] In related technologies, in order to reduce the dielectric constant of the PTFE insulation layer and thus reduce the energy loss of radio frequency signals during transmission, the industry generally adopts the PTFE wrapping technology with physical foaming technology. This technology uses a special wrapping machine to wind the PTFE green tape around the silver-plated copper inner conductor in a multi-layer wrapping manner or to perform wrapping after the solid PTFE insulation is extruded. This wrapping technology combined with the low-density green tape can effectively reduce the dielectric constant of the insulation layer to about 1.6.

[0004] Although the PTFE green tape wrapping technology has achieved certain results in reducing the dielectric constant, its production process is complex, its stability is insufficient, and there are problems such as poor bending resistance, insufficient electrical performance stability, and impedance non-uniformity. These problems limit the performance of PTFE cables in high-end applications, especially in occasions where high stability and consistency are required. Summary of the Invention

[0005] In order to solve the problems of large energy loss of the PTFE insulation layer during the transmission of radio frequency signals, as well as the complex production process, insufficient stability, poor bending resistance, insufficient electrical performance stability, and impedance non-uniformity of the existing PTFE green tape wrapping technology, the present application provides a PTFE physical foaming extrusion process.

[0006] The PTFE physical foaming extrusion process provided by the present application adopts the following technical solutions: A PTFE physical foaming extrusion process includes the following steps: Step 1: Wire pretreatment; Step 2: Wire extrusion molding; Step 3: Wire post-treatment and quality inspection; Step 4: Wire winding.

[0007] By adopting the above technical solutions, the Teflon physical foaming extrusion process can effectively improve the production quality and efficiency of cables through pre-treating the wire, extrusion molding, post-treatment, inspection, and winding. Specifically, the pre-treatment step ensures that the wire has a suitable diameter and temperature when entering the subsequent processes, improving the consistency and stability of the wire; the introduction of nitrogen injection during the extrusion molding process avoids plastic oxidation and improves the strength and surface quality of the insulation layer; the post-treatment and inspection steps include eccentricity detector inspection, constant temperature water bath treatment, air blowing device drying, single-layer cooling water bath cooling, and spray take-up machine treatment, ensuring the geometric accuracy and surface cleanliness of the wire; the final inspection device further verifies the performance indicators of the wire, ensuring that the product quality meets high-standard requirements. The entire process flow is rigorous and orderly, significantly improving the overall performance and reliability of the cable.

[0008] Optionally, the wire pre-treatment in step one further includes: a1: The wire releasing device releases the wire. a2: The wire diameter is measured by an outer diameter measuring instrument. a3: The wire is conveyed to a preheating device for preheating.

[0009] By adopting the above technical solutions, the wire pre-treatment process becomes more refined and standardized. First, the use of the wire releasing device ensures the smooth release of the wire at the initial stage, avoiding wire damage caused by mechanical jams. Second, the accurate measurement of the wire diameter by the outer diameter measuring instrument helps to promptly detect wire size deviations, thereby eliminating unqualified products in advance and improving the quality control level of subsequent processes. Finally, conveying the wire to the preheating device for preheating improves the temperature uniformity and plasticity of the wire, laying a good foundation for the subsequent extrusion molding step, reducing defects caused by uneven temperature, and enhancing the performance and reliability of the final product.

[0010] Optionally, the wire extrusion molding in step two further includes: b1: The preheated wire is conveyed to an extruder. b2: The extruder extrudes the molten plastic material and wraps it around the wire to form an insulation layer. b3: Nitrogen is injected during the extrusion process to prevent plastic oxidation.

[0011] By adopting the above technical solutions, the quality and stability of the insulating layer can be significantly improved during the processing of RF cables. Specifically, the preheated wire is conveyed to the extruder, which helps to improve the fluidity and melting effect of the plastic material, ensuring that the insulating layer evenly covers the surface of the wire. Injecting nitrogen during the extrusion process not only reduces the risk of plastic oxidation but also avoids the generation of bubbles caused by oxygen, thereby improving the density and mechanical strength of the insulating layer. Ultimately, this step can effectively reduce the energy loss during RF signal transmission and enhance the overall performance and reliability of the cable.

[0012] Optionally, the extruder includes a head carriage, a main machine, an auxiliary machine, and a nitrogen injection device. The head carriage carries and adjusts the extrusion die. The main machine is responsible for melting and conveying the plastic material. The auxiliary machine includes a wire feeding mechanism, a straightening mechanism, a preheating mechanism, a cooling mechanism, and a traction mechanism to cooperate in completing the transition from the pretreatment of the wire to the extrusion molding. The nitrogen injection device injects nitrogen into the extrusion area during the extrusion process to prevent the plastic material from oxidizing.

[0013] By adopting the above technical solutions, the head carriage accurately carries and flexibly adjusts the extrusion die, ensuring that the insulating layer can evenly and tightly wrap the surface of the wire to meet diverse production requirements. The main machine, as the core of the extrusion molding system, with its powerful melting and conveying capabilities, evenly heats the plastic material to the molten state, providing a solid foundation for the formation of a high-quality insulating layer. The auxiliary machine integrates a series of functions such as wire feeding, straightening, preheating, cooling, and traction. The various mechanisms cooperate closely to achieve a smooth transition of the wire from pretreatment to extrusion molding, ensuring the continuity and stability of the production process. Notably, the nitrogen injection device accurately injects nitrogen into the extrusion area during the extrusion process, effectively isolating the oxygen in the air, significantly reducing the risk of plastic material oxidation, and further enhancing the density, mechanical strength, and durability of the insulating layer, promoting a double leap in the quality and efficiency of cable processing.

[0014] Optionally, the main machine includes an extrusion mechanism, a transmission mechanism, and a heating and cooling mechanism. The extrusion mechanism includes a screw and a barrel. The transmission mechanism includes a motor and a reducer. The heating and cooling mechanism ensures that the plastic maintains an appropriate temperature during melting and extrusion.

[0015] By adopting the above technical solutions, the extrusion mechanism, with the screw and the barrel as the core, applies a strong shearing force and extrusion force to the plastic material entering the barrel through the rotational movement of the screw, making it uniformly heated and gradually melted, laying a solid foundation for subsequent extrusion molding. The transmission mechanism consists of a high-performance motor and a reducer, providing a stable and powerful power output for the screw, ensuring the continuity and stability of the extrusion process. The heating and cooling mechanism, as the intelligent brain for temperature control, monitors and adjusts the temperatures of the barrel and the screw in real time through a precise temperature control system, ensuring that the plastic is always within the optimal process temperature range during melting and extrusion, effectively avoiding material degradation or poor extrusion caused by too high or too low temperatures, thereby greatly improving the uniformity, density, and mechanical strength of the insulating layer.

[0016] Optionally, the post-treatment and quality inspection of the wire in step three include: c1: Transmitting the wire after extrusion molding to an eccentricity detector for inspection; c2: Sequentially transmitting the wire to a processing device for processing; c3: Transmitting it to a detection device for inspection through a wire storage and buffer device.

[0017] By adopting the above technical solutions, the wire after extrusion molding is first transmitted to an eccentricity detector for inspection, which can timely detect and correct the eccentricity problem of the wire, ensuring the concentricity and uniformity of the wire. Subsequently, the wire is sequentially transmitted to a processing device for processing, including a constant temperature water bath, a blowing device composed of an air pipe and a blower, a single-layer cooling water bath, and a spray take-up machine. This step can effectively remove the moisture on the surface of the wire, ensure the dryness of the wire, and at the same time, through gradual cooling and shaping, avoid stress concentration and deformation caused by rapid cooling. Finally, it is transmitted to a detection device for inspection through a wire storage rack. An outer diameter measuring instrument, a concavity and convexity instrument, and a spark tester are used to detect the outer diameter, concavity and convexity, and internal defects of the wire respectively, comprehensively ensuring the quality and performance of the wire, and improving the stability and consistency of the RF cable.

[0018] Optionally, the processing device in step c2 includes a constant temperature water bath, a blowing device composed of an air pipe and a blower, a single-layer cooling water bath, a spray take-up machine, and a wire storage rack.

[0019] By adopting the above technical solutions, the constant temperature water bath can ensure that the wire maintains a stable temperature during processing, avoiding changes in material properties caused by temperature fluctuations; the air pipe and blower in the blowing device can quickly remove the moisture on the surface of the wire, improving the efficiency and quality of subsequent processes; the single-layer cooling water bath helps the wire cool down quickly, preventing deformation or damage caused by overheating; the spray take-up machine can guide the wire while cooling, ensuring that it is straight and non-twisted; the wire storage rack plays a role of temporary storage, facilitating the continuous operation of the production line and improving production efficiency.

[0020] Optionally, the detection device in step c3 includes an outer diameter measuring instrument for detecting the outer diameter of the wire, a concavo-convex instrument for detecting the concavo-convex degree of the wire, and a spark tester for detecting internal defects of the wire.

[0021] By adopting the above technical solution, the outer diameter measuring instrument can accurately measure the outer diameter of the wire, ensure that it meets the specified dimensional requirements, and avoid unstable signal transmission caused by uneven outer diameter. The concavo-convex instrument can detect the flatness of the wire surface, timely discover and remove wires with surface defects, and improve the appearance quality and mechanical properties of the product. The spark tester can detect whether there are internal defects in the wire, such as cracks and holes, ensure the reliable electrical performance of the wire, and avoid failures during use.

[0022] Optionally, the wire winding in step d further includes: d1: Pass the qualified wire through the guiding device; d2: Use the wire take-up device to wind the wire.

[0023] By adopting the above technical solution, it can ensure that the qualified wires are neatly wound during the winding process, avoiding damage or quality problems caused by messy wires. The effective use of the guiding device can guide the wire to smoothly enter the wire take-up device, reduce the friction and wear of the wire during winding, thereby improving the yield and product quality. The wire take-up device can adapt to wires of different specifications and lengths, improving production efficiency and automation level.

[0024] Optionally, after the wire pre-treatment in step one, an intermediate inspection step of the wire is added, specifically including: e1: Transfer the wire to the intermediate inspection device; e2: Use the intermediate inspection device to conduct a preliminary inspection on the wire, and then carry out subsequent processes after excluding unqualified products.

[0025] By adopting the above technical solution, an intermediate inspection step of the wire is added, specifically including transferring the wire to the intermediate inspection device and using the intermediate inspection device to conduct a preliminary inspection on the wire, and then carrying out subsequent processes after excluding unqualified products. This can ensure that the wires entering the subsequent processes are all qualified products, reduce waste and rework caused by initial unqualified products, and improve the quality and production efficiency of the final product.

[0026] In summary, the present application includes at least one of the following beneficial technical effects: 1. By injecting nitrogen during the extrusion process, the oxidation of the plastic material is effectively prevented, the mechanical strength and surface quality of the insulating layer of the RF cable are improved, and the performance degradation caused by oxidation is reduced; 2. The components of the extruder work together to ensure the uniform melting and stable transportation of plastic materials, improve the automation level and production efficiency of the production line, and solve the problems of complex production process and insufficient stability in the traditional Teflon wrapping technology. 3. Systematic post-treatment and detection steps, including eccentricity detector detection, constant temperature water bath cooling, air blowing device drying, secondary cooling in a single-layer cooling water bath, spray take-up machine treatment, and the comprehensive use of various detection instruments, ensure the electrical performance stability and consistency of the final product, and eliminate the phenomenon of uneven impedance. Brief Description of the Drawings

[0027] Figure 1 It is a schematic flow chart of the Teflon physical foaming extrusion process in Embodiment 1 of the present application.

[0028] Figure 2 It is a schematic flow chart of the wire pretreatment process in Embodiment 1 of the present application.

[0029] Figure 3 It is a schematic flow chart of the wire pretreatment process in Embodiments 1 and 5 of the present application.

[0030] Figure 4 It is a schematic flow chart of the wire post-treatment and quality inspection process in Embodiments 1, 3, and 4 of the present application.

[0031] Figure 5 It is a schematic flow chart of the wire winding process in Embodiment 1 of the present application.

[0032] Figure 6 It is a schematic flow chart of the wire intermediate inspection process in Embodiment 2 of the present application. Detailed Description of the Embodiments

[0033] The following further elaborates on the present application in conjunction with the attached Figure 1-6 drawings.

[0034] The terms used in the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. Unless otherwise defined, the technical terms or scientific terms used in the present application should have the ordinary meaning understood by those skilled in the art to which the present application pertains. The "first", "second", and similar terms used in the present application do not denote any order, quantity, or importance, but are only used to distinguish different components.

[0035] Embodiment 1 The embodiment of the present application discloses a Teflon physical foaming extrusion process. Referring to Figure 1 and Figure 2 , the Teflon physical foaming extrusion process includes steps such as wire pretreatment, wire extrusion molding, wire post-treatment and quality inspection, and wire winding. Among them, the wire pretreatment includes the following steps: a1: The wire feeding device releases the wire; a2: The diameter of the wire is measured by an outer diameter measuring instrument; a3: The wire is conveyed to a preheating device for preheating.

[0036] Specifically, the wire feeding device can be an automated wire feeding device, whose function is to smoothly release the wound wire and feed it into the production line. The outer diameter measuring instrument is used to accurately measure the diameter of the wire to ensure that the wire has a stable size during subsequent processing. The preheating device adopts the AH-3150M high-configuration preheating device. By preheating the wire, the fluidity of the plastic material is improved, facilitating the subsequent extrusion molding process. Refer to Figure 3 , where the wire extrusion molding includes the following steps: b1: Convey the preheated wire to the extruder; b2: The extruder extrudes the molten plastic material and wraps it around the wire to form an insulating layer; b3: Inject nitrogen during the extrusion process to prevent the plastic from oxidizing.

[0037] Specifically, the extruder includes a head carriage, a main machine, an auxiliary machine, and a nitrogen injection system. The head carriage bears and adjusts the extrusion die, enabling the operator to conveniently replace the die or adjust the extrusion position. The main machine consists of an extrusion mechanism, a transmission mechanism, and a heating and cooling mechanism. The extrusion mechanism includes a screw and a barrel, which are responsible for melting and extruding the plastic raw material; the transmission mechanism consists of a motor and a reducer, providing the torque and speed required for the screw to rotate; the heating and cooling mechanism ensures that the plastic maintains an appropriate temperature during melting and extrusion. The auxiliary machine includes a wire feeding mechanism, a straightening mechanism, a preheating mechanism, a cooling mechanism, and a traction mechanism. These components work together to ensure the smooth progress of the extrusion process. The nitrogen injection system is used to inject nitrogen into the extruder to reduce the oxidation chance of the plastic at high temperatures and improve the quality of the product. Refer to Figure 4 , where the wire post-treatment and quality inspection include the following steps: c1: Convey the wire after extrusion molding to an eccentricity detector for inspection; c2: Convey the wire to a processing device for processing in sequence; c3: Convey it to a detection device for inspection through a wire storage rack.

[0038] Specifically, the processing device includes a constant temperature water bath, a blowing device composed of an air pipe and a blower, a single-layer cooling water bath, a spray take-up machine, and a wire storage rack. The constant temperature water bath is used to maintain the wire at a specific temperature to ensure the stability of its physical properties. The blowing device includes an air pipe and a blower, which are used to dry the moisture on the surface of the wire to avoid the influence of moisture on subsequent processes. The single-layer cooling water bath is used to quickly cool the wire to fix its shape. The spray take-up machine further cools the wire by spraying and leads it out. The wire storage rack is used to temporarily store the processed wire for the continuous progress of subsequent processes. The detection device includes an outer diameter measuring instrument, a concavo-convex instrument, and a spark tester, which are used to detect the outer diameter, concavo-convex degree, and internal defects of the wire respectively to ensure product quality. Refer to Figure 5 , in which, the wire winding includes the following steps: d1: Pass the qualified wire through the guiding device; d2: Use the wire take-up device to wind the wire.

[0039] Specifically, the guiding device is used to guide the wire into the wire take-up device to ensure that the wire is wound neatly and orderly. The wire take-up device is a device with a high degree of automation, which can efficiently wind the wire into a standard disc shape or other specified forms for easy storage and transportation.

[0040] The implementation principle of this embodiment is as follows: After the wire release device releases the wire and tests the diameter through a diameter measuring instrument, use the AH-3150M high-profile preheater to preheat the wire; transfer the preheated wire to an extruder including a head trolley, a main machine, an auxiliary machine, and a nitrogen injection system for extrusion molding. The auxiliary machine includes wire release, straightening, preheating, cooling, and traction devices, and the nitrogen injection system is used to prevent plastic oxidation; the wire after extrusion molding is detected by an eccentricity instrument, and then processed through a constant temperature water bath, a blowing device composed of an air pipe and a blower, a single-layer cooling water bath, and a spray take-up machine in sequence; the processed wire is transferred to a detection device including a diameter measuring instrument, a concavo-convex instrument, and a spark tester through a wire storage rack for detection; the qualified wire passes through the guiding device and is transferred to the wire take-up device for winding. In the whole technological process, each step is closely connected to ensure that the wire is effectively processed and detected in each link, thereby improving the overall quality and performance of the RF cable. Especially by introducing the nitrogen injection system, the oxidation risk of plastic at high temperature is reduced, and the durability and stability of the product are significantly improved. Refer to Embodiment 2 Figure 6 , the difference between this embodiment and the above embodiment is that a wire intermediate inspection step is added, which specifically includes the following steps: e1: Transfer the wire to the intermediate inspection device; e2: Use the intermediate inspection device to conduct a preliminary inspection on the wire, and exclude unqualified products before proceeding with subsequent processes.

[0041] Specifically, the intermediate inspection device includes, but is not limited to, a vision inspection system, an ultrasonic inspection system, and a resistance inspection system. The vision inspection system captures wire images through a camera to identify surface defects and foreign objects; the ultrasonic inspection system emits ultrasonic pulses to detect voids and cracks inside the wire; the resistance inspection system measures the resistance value of the wire to determine whether its electrical conductivity meets the requirements. By combining these inspection means, defective products can be detected and removed in a timely manner at an early stage, avoiding unnecessary resource waste and quality problems. The implementation principle of this embodiment is: by adding an intermediate inspection step for the wire, the quality control level in the production process is effectively improved. Before each step, defective wires are pre-screened to ensure that only wires meeting the standards enter the next process, thereby greatly reducing the scrap rate and improving production efficiency and the yield rate. Refer to Embodiment 3 Figure 4 , the difference between this embodiment and the above-mentioned embodiment lies in that different cooling methods are adopted in the wire post-treatment and quality inspection processes, specifically as follows: c1: Transmit the extruded wire to an eccentricity detector for inspection; c2: Transmit the wire to a processing device for processing in sequence; c3: Transmit it to a detection device for inspection through a wire storage rack.

[0042] Specifically, the processing device includes a liquid nitrogen cooling pool, a blast drying device, a double-layer cooling water tank, a spray take-up machine, and a wire storage rack. The liquid nitrogen cooling pool uses low-temperature liquid nitrogen to quickly cool the wire and make it solidify rapidly, which is suitable for special occasions that require an extremely high cooling rate. The blast drying device blows cold air onto the wire surface through a high-speed fan to accelerate water evaporation and ensure that the wire is completely dry. The double-layer cooling water tank is divided into two sections. The first section uses cold water at a lower temperature, and the second section uses hot water at a higher temperature to gradually cool down, avoiding stress concentration in the wire due to rapid cooling. The functions of the spray take-up machine and the wire storage rack are the same as those in the previous embodiments. The implementation principle of this embodiment is: by adopting a liquid nitrogen cooling pool and a blast drying device, a more efficient cooling and drying process is achieved. The liquid nitrogen cooling pool can reduce the temperature of the wire to the required temperature in an extremely short time, which is especially suitable for application scenarios that require rapid solidification. The blast drying device accelerates water evaporation through high-speed air flow to ensure that there is no residual water on the wire surface, which is beneficial to the subsequent processes. This cooling method not only improves production efficiency but also better protects the physical properties of the wire and extends its service life. Refer to Embodiment 4 Figure 4 , the difference between this embodiment and the above-mentioned embodiment lies in that different detection instruments and technologies are adopted, specifically including the following steps: c1: Transmit the extruded wire to an eccentricity detector for inspection; c2: Transmit the wire to a processing device for processing in sequence; c3: Transmit it to a detection device for inspection through a wire storage rack.

[0043] Specifically, the detection device includes a laser rangefinder, a 3D scanner, and an X-ray detector. The laser rangefinder measures the outer diameter of the wire by laser beam, with high precision and fast speed. The 3D scanner can generate a 3D model of the wire to comprehensively evaluate its geometric shape and surface quality. The X-ray detector has strong penetrability and can detect internal defects of the wire, such as voids, cracks, etc. The combination of these advanced detection technologies can more accurately and comprehensively evaluate the quality of the wire, ensuring that every detail meets the standards. The implementation principle of this embodiment is: by introducing a laser rangefinder, a 3D scanner, and an X-ray detector, the detection accuracy and reliability are greatly improved. The laser rangefinder can monitor the change of the outer diameter of the wire in real time to ensure its dimensional consistency. The 3D scanner provides an all-round view of the wire to help engineers discover potential deformations and surface defects. The X-ray detector penetrates deep into the wire to reveal hidden structural problems. The application of these technologies not only improves the product quality but also shortens the detection time and speeds up the production rhythm. Example 5 Refer to Figure 3 , the difference between this embodiment and the above embodiment is that different auxiliary equipment and process parameters are adopted in the extrusion molding process, which specifically includes the following steps: b1: Transfer the preheated wire to the extruder; b2: The extruder extrudes the molten plastic material and wraps it around the wire to form an insulating layer; b3: Inject nitrogen during the extrusion process to prevent the plastic from oxidizing.

[0044] Specifically, the main part of the extruder adopts a twin-screw structure instead of the traditional single-screw structure. The twin-screw structure can provide better mixing effect and higher extrusion rate, while reducing energy consumption. The auxiliary part is equipped with a vibration straightening device to eliminate the bending and twisting of the wire through high-frequency vibration, ensuring that the wire is in the best state before extrusion. The temperature control range of the preheating device is also expanded to support lower and higher preheating temperatures to adapt to the wire requirements of different materials. The flow regulation of the nitrogen injection system is more accurate, and the nitrogen injection amount can be dynamically adjusted according to the actual working conditions to ensure that the plastic material is always in an ideal inert environment. The implementation principle of this embodiment is: by optimizing the structure of the main and auxiliary parts of the extruder and improving the performance of the preheating device and the nitrogen injection system, a more efficient and higher-quality production process is achieved. The introduction of the twin-screw structure significantly improves the mixing effect of the plastic material, increases the extrusion speed and output. The effective application of the vibration straightening device eliminates the bending and twisting of the wire, ensuring the straightness of the wire during extrusion. The expansion of the temperature control range of the preheating device enables the production equipment to flexibly handle various types of wires, broadening the applicable range. The refined regulation of the nitrogen injection system flow minimizes the oxidation risk of the plastic material, ensuring the long-term stability and reliability of the product. These improvement measures not only improve the production efficiency but also greatly enhance the product quality and customer satisfaction.

[0045] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereby. Therefore, all equivalent changes made according to the structure, shape and principle of the present application shall be covered within the protection scope of the present application.

Claims

1. A Teflon physical foaming extrusion process, characterized in that: The following steps are involved: Step 1: Wire pretreatment; Step 2: wire extrusion molding; Step 3: Wire post-processing and quality inspection; Step 4: Wire coiling.

2. A Teflon physical foaming extrusion process according to claim 1, characterized in that: The wire pretreatment in step 1 further includes: a1: The pay-off device releases the wire; a2: Test the wire diameter using an outer diameter measuring instrument; a3: Transfer the wire to the preheating device for preheating.

3. A Teflon physical foaming extrusion process according to claim 1, characterized in that: The wire extrusion molding in step 2 further comprises: b1: convey the preheated wire to the extruder; b2: The extruder extrude the molten plastic material and wrap it on the wire to form an insulation layer; b3: Inject nitrogen during the extrusion process to prevent plastic oxidation.

4. A Teflon physical foaming extrusion process according to claim 3, characterized in that: The extruder includes a head trolley, a main machine, an auxiliary machine and a nitrogen injection device. The head trolley carries and adjusts the extrusion mold, the main machine is responsible for melting and conveying the plastic material, and the auxiliary machine includes a wire-releasing mechanism, a straightening mechanism, a preheating mechanism, a cooling mechanism and a traction mechanism to collaboratively complete the transition from wire pretreatment to extrusion molding; the nitrogen injection device injects nitrogen into the extrusion area during the extrusion process to prevent oxidation of the plastic material.

5. A Teflon physical foaming extrusion process according to claim 4, characterized in that: The main machine comprises an extrusion mechanism, a transmission mechanism and a heating and cooling mechanism. The extrusion mechanism comprises a screw and a barrel. The transmission mechanism comprises a motor and a reducer. The heating and cooling mechanism ensures that the plastic maintains an appropriate temperature during the melting and extrusion process.

6. A Teflon physical foaming extrusion process according to claim 1, characterized in that: The wire post-processing and quality inspection in step 3 include: c1: The extruded wire is sent to the eccentricity detector for testing; c2: The wires are sequentially conveyed to the processing device for processing; c3: It is transmitted to the detection device for detection through the wire storage buffer device.

7. A Teflon physical foaming extrusion process according to claim 6, characterized in that: The processing device in step c2 includes a constant temperature water tank, an air blowing device composed of an air pipe and a fan, a single-layer cooling water tank, a spraying and drawing machine, and a wire storage rack.

8. A Teflon physical foaming extrusion process according to claim 6, characterized in that: The detection device in step c3 includes an outer diameter measuring instrument for detecting the outer diameter of the wire, a concave-convex meter for detecting the concave-convexity of the wire, and a spark machine for detecting internal defects of the wire.

9. A Teflon physical foaming extrusion process according to claim 1, characterized in that: Wherein step d of wire coiling further comprises: d1: Pass the qualified wire through the guide device; d2: Use the wire take-up device to reel in the wire.

10. A Teflon physical foaming extrusion process according to claim 1, characterized in that: It also includes adding a wire intermediate inspection step after the wire pretreatment in step one, specifically including: e1: convey the wire to the intermediate inspection device; e2: Use the intermediate inspection device to conduct preliminary inspection on the wire, and then proceed to the subsequent process after eliminating unqualified products.

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