A manufacturing method of an environment-friendly low-smoke and halogen-free cable

Abstract

The present invention relates to the field of cables, and particularly to a manufacturing method of an environment-friendly low-smoke and halogen-free cable, comprising the following steps: concentrically stranding a plurality of metal wires to obtain a core, and feeding the core into an extruder; the extruder sequentially extrudes a filler and an insulating layer outside the core to obtain a first semi-finished cable; a braiding machine uses copper wires to braid a shielding layer outside the first semi-finished cable to obtain a second semi-finished cable; the extruder extrudes a protective sheath on the second semi-finished cable to obtain a cable to be detected; detecting the quality of the cable to be detected to determine whether the quality of the cable is qualified. The protective sheath is made of a halogen-free material, and the protective sheath is used to protect the internal structure of the cable. By using halogen-free materials to manufacture the cable, compared with other cables, the harmful gases generated during combustion are less, and the pollution degree is lower, which is beneficial to reducing the damage caused by cable combustion to the human body or the environment and is beneficial to improving the environmental protection of the cable.

Description

Technical Field

[0001] The present invention relates to the field of cables, and particularly to a manufacturing method of an environment-friendly low-smoke and halogen-free cable. Background Art

[0002] Insulating materials commonly used in traditional cables include polyvinyl chloride (PVC), cross-linked polyethylene (XLPE), etc. These materials have certain properties in electrical insulation and mechanical protection, but they will release toxic gases and smoke when burning, which pose hazards to the environment and human health. To solve this problem, many halogen-free cables have emerged.

[0003] For example, the prior art of CN105702346A discloses a smokeless and halogen-free network cable. An outer sheath made of a smokeless and halogen-free material is provided outside the inner sheath. A compressive component is provided between the inner sheath and the outer sheath. The compressive component includes a compressive ring provided on the outer wall of the inner sheath. Three annularly distributed compressive arc bodies are provided on the inner wall of the outer sheath. Each compressive arc body is connected to the compressive ring through an elastic member. A gap is left between adjacent two compressive arc bodies. Adjacent two compressive arc bodies are connected by a flexible compressive belt. A shielding layer is also compounded in the outer sheath.

[0004] Another typical prior art of CN102136317B discloses a halogen-free flame-retardant cable, which can obtain high flame retardancy and can also suppress the generation of gaps between the insulated wire and the coating even under electron beam irradiation, preventing the reduction of the bonding strength. The halogen-free flame-retardant cable is provided with an inner layer outside a multi-core stranded wire formed by twisting a plurality of insulated wires having an insulating layer on the outer periphery of a conductor, and an outer layer is provided on the inner layer. The outer layer is composed of a resin composition containing 30 parts by mass or more of a flame retardant relative to 100 parts by mass of thermoplastic polyurethane (TPU). The inner layer is composed of a resin composition containing ethylene-vinyl acetate copolymer (EVA) with an acetic acid component (VA) content of 33% or more. The outer layer is cross-linked.

[0005] Another example is the prior art of CN104952527A, which discloses a halogen-free flame-retardant cable including an insulating sheath. A flame-retardant layer is provided inside the insulating sheath. A sealed connection is adopted between the flame-retardant layer and the insulating sheath. An aluminum-clad layer is provided inside the flame-retardant layer. A fireproof cotton layer is provided between the aluminum-clad layer and the flame-retardant layer. Spring pieces are vertically connected between the insulating sheath, the flame-retardant layer and the aluminum-clad layer. The spring pieces are clamped on the insulating sheath, the flame-retardant layer and the aluminum-clad layer. Connecting columns are horizontally installed on the spring pieces. The connecting columns are fixed on the spring pieces. Wire connection joints are installed on the connecting columns. Fixing holes are also opened on the spring pieces. A spring sleeve is connected to one side of the spring piece. The spring sleeve and the spring piece are connected through an internal screw. An insurance device is installed inside the spring sleeve.

[0006] At present, the quality inspection of halogen-free cables is relatively simple and the inspection is not comprehensive enough. In order to solve the problems commonly existing in this field, the present invention is made. Summary of the Invention

[0007] The purpose of the present invention is to propose a manufacturing method for an environmentally friendly low-smoke halogen-free cable in view of the current deficiencies.

[0008] In order to overcome the deficiencies of the prior art, the present invention adopts the following technical solutions:

[0009] A manufacturing method for an environmentally friendly low-smoke halogen-free cable, the manufacturing method of the cable comprising the following steps:

[0010] S1. Concentrically stranding a plurality of metal wires to obtain a core, and feeding the core into an extruder;

[0011] S2. The extruder extrudes a filler and an insulating layer on the outside of the core in sequence to obtain a first semi-finished cable;

[0012] S3. A braiding machine uses copper wires to braid a shielding layer on the outside of the first semi-finished cable to obtain a second semi-finished cable;

[0013] S4. The extruder extrudes a protective sheath on the second semi-finished cable to obtain a cable to be detected;

[0014] S5. Detect the quality of the cable to be detected to judge whether the quality of the cable is qualified.

[0015] Furthermore, the cable includes a core, a filler, an insulating layer, a shielding layer and a protective sheath. The core includes a copper conductor and is used for transmitting electric energy; the filler is arranged in the gap between the core and the insulating layer and is used for maintaining the structural stability inside the cable. The filler can be polyethylene or polypropylene; the insulating layer is made of a halogen-free material and is used for preventing the leakage of electric energy of the cable or short circuit of the cable; the shielding layer is braided by a plurality of copper wires and is used for reducing electromagnetic interference; the protective sheath is made of a halogen-free material and is used for protecting the internal structure of the cable; the outer diameter of the cable is greater than 20 mm;

[0016] The manufacturing method of the cable further includes a method for evaluating the quality of the cable. The method evaluates whether the cable manufactured by this manufacturing method is qualified by calculating the quality index of the cable and judging the magnitude relationship between the quality index of the cable and a set threshold value.

[0017] Furthermore, the raw materials of the insulating layer of the cable include zinc borate, polyphosphazene flame retardant, smoke-suppressing inorganic flame retardant, polymer substrate, antioxidant and anti-radiation agent.

[0018] Further, the components of the raw material of the cable's protective sleeve by weight are: 5-6 parts of saturated polyester, 14-16 parts of high polystyrene, 2-3 parts of stearic acid, 6-8 parts of ferric oxide, 3-4 parts of aluminum silicate, 8-10 parts of polyurethane, 1-3 parts of triethylenediamine, 2-4 parts of phosphogypsum, 2-3 parts of methyl silicone oil, 2-5 parts of silicone, and 48-52 parts of ethylene-propylene rubber.

[0019] Further, the diameter of the cable is 50 mm, the thickness of the protective sleeve is 8 mm, the outer surface of the protective sleeve includes a plurality of adjacent protrusions, the grooves between the protrusions are for injecting insect repellent substances, and the depth of the grooves is 4 mm.

[0020] Further, detecting the quality of the cable to be detected includes the following steps:

[0021] S51, Set the combustion grade, burn the cable to be detected at each combustion grade in ascending order of combustion temperature, and each combustion lasts for a period of time;

[0022] S52, Collect the gases generated during the combustion process and identify the gases generated during the combustion process;

[0023] S53, After the last combustion ends, remove the ignition source and obtain the time required for the cable to be detected to self-extinguish after the ignition source is removed;

[0024] S54, Detect the weight of the remaining cable to be detected and calculate the quality index of the cable.

[0025] Further, calculating the quality index of the cable includes the following steps:

[0026] S551, According to the results of gas identification, obtain the types of harmful gases generated in each combustion stage and the concentrations of various harmful gases;

[0027] S552, According to the ratio of the concentration of harmful gases generated by combustion per unit time to the total gas concentration, judge the combustion grade at which the cable starts to burn and the combustion grade at which the cable starts to burn violently;

[0028] S553, Calculate the flame retardancy performance index of the cable according to the relevant information;

[0029] S554, Calculate the pollution performance index according to the relevant information;

[0030] S555, Judge whether the pollution performance index is 0. If it is 0, it is considered that the cable quality is unqualified. Otherwise, calculate the quality index according to the relevant information:

[0031] ZB = k3 * ZB1 + k4 * ZB2

[0032] Among them, ZB is the quality index, ZB1 is the flame retardant performance index, k3 is the weight of the flame retardant performance, ZB2 is the pollution performance index, k4 is the weight of the pollution performance. When the quality index of the cable is greater than the set threshold, the cable is considered qualified; otherwise, it is considered unqualified.

[0033] Furthermore, it also includes a cable manufacturing system, which includes a raw material storage module, a cable production module, a cable quality inspection module, and a data analysis module. The raw material storage module is used to store the raw materials for manufacturing the cable. The cable production module includes a robotic arm, a conveyor belt, an extruder, and a braiding machine. The robotic arm is used to extract the raw materials from the raw material storage module and place them on the conveyor belt. The conveyor belt is used to transport the raw materials to the extruder. The extruder is used to extrude and form each layer of the cable. The braiding machine is used to braid the shielding layer of the cable. The cable quality inspection module includes a fire source, a temperature detection unit, a gas detection unit, a weight detection unit, and a timing unit. The fire source is used to burn the cable. The temperature detection unit is used to detect the combustion temperature. The gas detection unit is used to detect the types and concentrations of the gases generated during the combustion process. The weight detection unit is used to detect the remaining weight of the cable after combustion. The timing unit is used to time during the quality inspection process. The data analysis module includes a data acquisition module, a calculation module, and a comparison module. The data acquisition module is used to collect various parameters of the cable quality inspection module. The calculation module is used to calculate the quality index of the cable. The comparison module is used to compare the quality index of the cable with the set threshold to determine whether the quality of the cable is qualified.

[0034] Beneficial effects of this solution: 1. By using halogen-free materials to manufacture the cable, compared with other cables, less harmful gases are generated during combustion, and the degree of pollution is lower, which is beneficial to reducing the damage caused by cable combustion to the human body or the environment and improving the environmental protection of the cable.

[0035] 2. By setting the flame retardant performance index and the pollution performance index to calculate the quality index of the cable from two aspects, evaluating the quality of the cable from whether the cable is easy to burn and the harmful gases generated during cable combustion, and focusing on analyzing the environmental protection level of the cable, which is beneficial to evaluating the quality of the cable from the environmental protection level and thus determining whether the cable meets the requirements of environmentally friendly low-smoke halogen-free cables. Description of the Drawings

[0036] The present invention can be further understood from the following description in conjunction with the drawings. The components in the drawings are not necessarily drawn to scale, but the focus is on showing the principles of the embodiments. In different views, the same reference numerals designate the same parts.

[0037] Figure 1 It is a schematic diagram of the cable structure of the present invention.

[0038] Figure 2 This is the flowchart for manufacturing the cable of the present invention.

[0039] Figure 3 This is the flowchart for quality inspection of the cable of the present invention.

[0040] Figure 4 This is the flowchart for calculating the quality index of the cable of the present invention.

[0041] Reference numerals: conductor core 01, insulating layer 02, shielding layer 03, protective sheath 04. Detailed implementation manners

[0042] The following are specific embodiments to illustrate the implementation manners of the present invention. Those skilled in the art can understand the advantages and effects of the present invention from the content disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments, and various details in this specification can also be modified and changed based on different viewpoints and applications without departing from the spirit of the present invention. Additionally, the drawings of the present invention are only simple schematic illustrations and are not drawn according to actual sizes, hereby declared. The following implementation manners will further detail the related technical content of the present invention, but the disclosed content is not used to limit the protection scope of the present invention.

[0043] Embodiment 1: According to Figure 1 , Figure 2 and Figure 3 , this embodiment provides a method for manufacturing an environmentally friendly low-smoke and halogen-free cable. The manufacturing method of the cable includes the following steps:

[0044] S1. Concentrically stranding a plurality of metal wires to obtain a conductor core, and feeding the conductor core into an extruder;

[0045] S2. The extruder extrudes a filler and an insulating layer on the outer side of the conductor core in sequence to obtain a first semi-finished cable;

[0046] S3. A braiding machine uses copper wires to braid a shielding layer on the outer side of the first semi-finished cable to obtain a second semi-finished cable;

[0047] S4. The extruder extrudes a protective sheath on the second semi-finished cable to obtain a cable to be inspected;

[0048] Specifically, the protrusions and grooves on the protective sheath can be obtained by adjusting the die during extrusion of the extruder.

[0049] S5. Inspecting the quality of the cable to be inspected to determine whether the quality of the cable is qualified.

[0050] Furthermore, the cable includes a core, a filler, an insulating layer, a shielding layer, and a protective sheath. The core includes a copper conductor and is used for transmitting electrical energy. The filler is disposed in the gap between the core and the insulating layer and is used to maintain the structural stability inside the cable. The filler can be polyethylene or polypropylene. The insulating layer is made of a halogen-free material and is used to prevent electrical energy leakage or short circuit of the cable. The shielding layer is woven by multiple copper wires and is used to reduce electromagnetic interference. The protective sheath is made of a halogen-free material and is used to protect the internal structure of the cable. The outer diameter of the cable is greater than 20 mm.

[0051] The method for manufacturing the cable further includes a method for evaluating the quality of the cable. The method evaluates whether the cable manufactured by this manufacturing method is qualified by calculating the quality index of the cable and judging the magnitude relationship between the quality index of the cable and the set threshold.

[0052] Furthermore, the raw materials of the insulating layer of the cable include zinc borate, polyphosphazene flame retardant, smoke-suppressing inorganic flame retardant, polymer substrate, antioxidant, and anti-radiation agent.

[0053] Specifically, the above raw materials are all made of halogen-free materials. For example, the polymer substrate includes polyvinyl chloride and polystyrene, etc. Polyvinyl chloride containing halogen (chlorine) is not used in this solution.

[0054] Furthermore, the raw materials of the protective sheath of the cable are composed of the following components by weight: 5-6 parts of saturated polyester, 14-16 parts of high polystyrene, 2-3 parts of stearic acid, 6-8 parts of ferric oxide, 3-4 parts of aluminum silicate, 8-10 parts of polyurethane, 1-3 parts of triethylenediamine, 2-4 parts of phosphogypsum, 2-3 parts of methyl silicone oil, 2-5 parts of silicone, and 48-52 parts of ethylene-propylene rubber.

[0055] Furthermore, the diameter of the cable is 50 mm, the thickness of the protective sheath is 8 mm, the outer surface of the protective sheath includes a plurality of adjacent protrusions, the grooves between the protrusions are used for injecting insect repellent substances, and the depth of the grooves is 4 mm.

[0056] Specifically, by setting the protrusions and grooves, the fluidity on the surface of the protective layer can be reduced, thereby preserving the insect repellent substances and further improving the continuous effect of the insect repellent substances.

[0057] Furthermore, detecting the quality of the cable to be detected includes the following steps:

[0058] S51, set the combustion grade, and burn the cable to be detected at each combustion grade in ascending order of combustion temperature, and each combustion lasts for a period of time.

[0059] Specifically, the duration of each combustion is the same, and this time is set by those skilled in the art;

[0060] S52, Collect the gas generated during the combustion process and identify the gas generated during the combustion process;

[0061] S53, After the last combustion ends, remove the ignition source and obtain the time required for the cable to be tested to extinguish itself after the ignition source is removed;

[0062] S54, Detect the weight of the remaining cable to be tested and calculate the quality index of the cable.

[0063] Furthermore, calculating the quality index of the cable includes the following steps:

[0064] S551, According to the result of gas identification, obtain the types of harmful gases generated in each combustion stage and the concentration of each harmful gas;

[0065] Specifically, the types of harmful gases can be obtained by infrared spectroscopy or gas chromatography-mass spectrometry,

[0066] The concentration of each harmful gas can be obtained by a gas analyzer;

[0067] S552, According to the ratio of the concentration of harmful gases generated by combustion per unit time to the total gas concentration, judge the combustion level at which the cable starts to burn and the combustion level at which the cable starts to burn violently;

[0068] Specifically, the total gas concentration is the concentration of all gases generated during the combustion process in the identified gases. The identified gases include the gas generated by combustion and the air originally in the combustion space. When the ratio of the concentration of harmful gases generated by combustion per unit time to the total gas concentration is greater than its corresponding first threshold, it is considered that the cable starts to burn violently. When the ratio of the concentration of harmful gases generated by combustion per unit time to the total gas concentration is greater than its corresponding second threshold, it is considered that the cable starts to burn violently; the first threshold and the second threshold are set by those skilled in the art. When the cable has not started to burn, the harmful gases generated are relatively low, and the value of the first threshold can be 0.03. When the cable starts to burn violently, the harmful gases generated are relatively high, and the value of the second threshold can be 0.2;

[0069] S553, Calculate the flame retardant performance index of the cable according to relevant information:

[0070]

[0071] Among them, ZB1 is the flame retardancy performance index, time is the time required for the cable to be tested to self-extinguish after the fire source is removed, k2 is the weight of intense combustion, k1 is the weight of ignition, level2 is the combustion temperature value corresponding to the combustion level when intense combustion starts, level1 is the combustion temperature value corresponding to the combustion level when ignition starts, level max is the combustion temperature value corresponding to the maximum combustion level, and e is the natural constant;

[0072] Specifically, the flame retardancy performance index is used to characterize whether the cable to be tested is prone to combustion. The larger the value of the index, the less likely the cable is to burn; the values of k1 and k2 are set by those skilled in the art. The value of k1 can take the value of the first threshold, and the value of k2 can take the value of the second threshold;

[0073] S554. Calculate the pollution performance index according to relevant information:

[0074]

[0075] Among them, ZB2 is the pollution performance index, I is the number of types of harmful gases generated when the combustion level is the maximum, a i is the concentration of the i-th type of harmful gas generated per unit time, b i is the toxicity weight of the i-th type of harmful gas, J is the number of types of harmful gases containing halogens among the harmful gases, a j is the concentration of the j-th type of harmful gas containing halogens generated per unit time, b j is the toxicity weight of the j-th type of harmful gas containing halogens, and G is the tolerance threshold;

[0076] Specifically, the toxicity weight is set by those skilled in the art according to the toxicity thresholds of each gas to the human body (i.e., the concentration that causes harm to the human body or the environment), and the toxicity thresholds can be queried through a database;

[0077] Specifically, ideally, the environmentally friendly low-smoke and halogen-free cable in this solution contains halogens in the harmful gases generated during combustion. However, in the actual production process, due to reasons such as impurities in the raw materials or insufficient equipment cleaning, the generated gases may contain halogens. When the sum of the concentrations of all harmful gases containing halogens is lower than the tolerance threshold, it is considered that the error is small, and the quality index can be calculated through the pollution performance index to evaluate the cable quality. When the sum of the concentrations of all harmful gases containing halogens is greater than the tolerance threshold, it is considered that the error is large, and the value of ZB2 is set to 0;

[0078] S555. Determine whether the pollution performance index is 0. If it is 0, it is considered that the cable quality is unqualified. Otherwise, calculate the quality index according to relevant information:

[0079] ZB = k3 * ZB1 + k4 * ZB2

[0080] Among them, ZB is the quality index, ZB1 is the flame retardant performance index, k3 is the flame retardant performance weight, ZB2 is the pollution performance index, k4 is the pollution performance weight. When the quality index of the cable is greater than the set threshold, the cable is considered qualified; otherwise, it is considered unqualified.

[0081] Specifically, k4 and k3 are set by those skilled in the art. The value of k3 can be the mass ratio of the cable to be tested before and after combustion, and the value of k4 can be the total concentration of the maximum harmful gases generated during the combustion process.

[0082] Specifically, the set threshold is set by those skilled in the art.

[0083] Specifically, when the value of ZB2 is 0, the quality index is not calculated and the cable is directly considered unqualified because at this time, the sum of the concentrations of all halogen-containing harmful gases generated by the cable combustion is greater than the tolerance threshold, and the error is large. Regardless of the calculation result of the quality index, the cable does not meet the "halogen-free" standard. Therefore, the cable is directly determined to be unqualified.

[0084] Furthermore, there is also a cable manufacturing system, including a raw material storage module, a cable production module, a cable quality detection module, and a data analysis module. The raw material storage module is used to store the raw materials for manufacturing the cable. The cable production module includes a robotic arm, a conveyor belt, an extruder, and a braiding machine. The robotic arm is used to extract the raw materials from the raw material storage module and place them on the conveyor belt. The conveyor belt is used to transport the raw materials to the extruder. The extruder is used to extrude and form each layer of the cable. The braiding machine is used to braid the shielding layer of the cable. The cable quality detection module includes a fire source, a temperature detection unit, a gas detection unit, a weight detection unit, and a timing unit. The fire source is used to burn the cable. The temperature detection unit is used to detect the combustion temperature. The gas detection unit is used to detect the types and concentrations of the gases generated during the combustion process. The weight detection unit is used to detect the remaining weight of the cable after combustion. The timing unit is used to time during the quality detection process. The data analysis module includes a data acquisition module, a calculation module, and a comparison module. The data acquisition module is used to collect the various parameters of the cable quality detection module. The calculation module is used to calculate the quality index of the cable. The comparison module is used to compare the quality index of the cable with the set threshold to determine whether the quality of the cable is qualified.

[0085] The beneficial effects of this solution: 1. By using halogen-free materials to manufacture cables, compared with other cables, less harmful gases are generated during combustion, and the pollution level is lower, which is beneficial to reducing the damage caused by cable combustion to the human body or the environment and improving the environmental protection of the cable.

[0086] 2. Calculate the quality index of the cable from two aspects by setting the flame retardancy performance index and the pollution performance index, evaluate the quality of the cable from whether the cable is easy to burn and the harmful gases generated during the combustion of the cable, and focus on analyzing the environmental protection level of the cable, which is beneficial to evaluating the quality of the cable from the environmental protection level, so as to judge whether the cable meets the requirements of the environmentally friendly low-smoke and halogen-free cable.

[0087] Example 2: This example should be understood as including all the features of any one of the foregoing examples and being further improved on this basis. According to Figure 4 , it also lies in that the weight values of each item can be obtained in the following ways:

[0088] For k1 and k2, they can be obtained according to the following steps:

[0089] STEP1, Collect various data obtained during the combustion of multiple combustion grades.

[0090] STEP2, Fit the data through the following fitting equation:

[0091] y1 = k1 * x1 + b1

[0092] y2 = k2 * x2 + b2

[0093] Wherein, x1 is the temperature value corresponding to the combustion grade between the start of combustion and the intense combustion, y1 is the total harmful gas concentration generated by the cable to be detected under the condition of x1, x2 is the temperature value corresponding to the combustion grade between the intense combustion corresponding combustion grade and the maximum combustion grade, y2 is the total harmful gas concentration generated by the cable to be detected under the condition of x2, and b1 and b2 are constants;

[0094] STEP3, Obtain the values of k1 and k2 according to the fitting results.

[0095] For b i and a j They can be obtained according to the following formula:

[0096] b i = lim i

[0097]

[0098] Wherein, lim i is the toxicity threshold of the i-th harmful gas to the human body, lim j is the toxicity threshold of the j-th harmful gas to the human body, num j1 is the number of atoms contained in the molecule corresponding to the j-th harmful gas, num j2is the number of atoms belonging to halogens contained in the molecule corresponding to the j-th harmful gas.

[0099] Advantages of this embodiment: By setting the weight in the way of fitting the existing data, it is beneficial to adjust the weight value according to the experimental data, making the weight more in line with the actual situation. By setting the weight according to the number of atoms and the toxicity threshold, it is beneficial to adjust the weight value according to the toxicity of the gas and the halogens contained in the gas, making the weight more in line with the actual situation.

[0100] The content disclosed above is only the preferred feasible embodiment of the present invention, and does not limit the protection scope of the present invention. Therefore, all equivalent technical changes made by using the content of the specification and drawings of the present invention are included in the protection scope of the present invention. In addition, the elements therein can be updated with the development of technology. The above units are only examples, and those skilled in the art can adopt corresponding units according to actual needs when implementing this solution.

Claims

1. A manufacturing method of an environmentally friendly low-smoke and halogen-free cable, characterized in that The cable manufacturing method includes the following steps: S1. Concentrically stranding several metal wires to obtain a core, and feeding the core into an extruder; S2. The extruder sequentially extrudes a filler and an insulating layer outside the core to obtain a first semi-finished cable; S3. A braiding machine uses copper wires to braid a shielding layer outside the first semi-finished cable to obtain a second semi-finished cable; S4. The extruder extrudes a protective sheath on the second semi-finished cable to obtain a cable to be tested; S5. Detect the quality of the cable to be tested to determine whether the quality of the cable is qualified; The cable includes a core, a filler, an insulating layer, a shielding layer and a protective sheath. The core includes a copper conductor and is used for transmitting electric energy; the filler is arranged in the gap between the core and the insulating layer and is used for maintaining the structural stability inside the cable, and the filler is polyethylene or polypropylene; the insulating layer is made of a halogen-free material and is used for preventing the leakage of electric energy of the cable or cable short circuit; the shielding layer is braided by multiple copper wires and is used for reducing electromagnetic interference; the protective sheath is made of a halogen-free material and is used for protecting the internal structure of the cable; the outer diameter of the cable is greater than 20 mm; The cable manufacturing method further includes a method for evaluating the quality of the cable. The method evaluates whether the cable manufactured by this manufacturing method is qualified by calculating the quality index of the cable and judging the size relationship between the quality index of the cable and a set threshold; Detecting the quality of the cable to be tested includes the following steps: S51. Set the combustion grade, and burn the cable to be tested at each combustion grade in the order of increasing combustion temperature, and each combustion lasts for a period of time; S52. Collect the gases generated during the combustion process and identify the gases generated during the combustion process; S53. After the last combustion ends, remove the fire source and obtain the time required for the cable to be tested to self-extinguish after the fire source is removed; S54. Detect the weight of the remaining cable to be tested and calculate the quality index of the cable; Calculating the quality index of the cable includes the following steps: S551. According to the results of gas identification, obtain the types of harmful gases generated at each combustion stage and the concentrations of various harmful gases; S552. According to the ratio of the concentration of harmful gases generated by combustion per unit time to the total gas concentration, judge the combustion grade at which the cable starts to burn and the combustion grade at which the cable starts to burn violently; S553. Calculate the flame retardant performance index of the cable according to relevant information; ； Among them, is the flame retardancy performance index, is the time required for the cable to be tested to self-extinguish after the fire source is removed, is the weight of intense combustion, is the weight of the start of combustion, is the combustion temperature value corresponding to the combustion level when intense combustion starts, is the combustion temperature value corresponding to the combustion level when combustion starts, is the combustion temperature value corresponding to the maximum combustion level, and e is the natural constant; S554. Calculate the pollution performance index according to relevant information; ； Among them, is the pollution performance index, I is the number of types of harmful gases generated when the combustion level is the highest, is the concentration of the i-th type of harmful gas generated per unit time, is the toxicity weight of the i-th type of harmful gas, J is the number of types of harmful gases containing halogens among the harmful gases, is the concentration of the j-th type of harmful gas containing halogens generated per unit time, is the toxicity weight of the j-th type of harmful gas containing halogens, and G is the tolerance threshold; S555. Judge whether the pollution performance index is 0. If it is 0, it is considered that the cable quality is unqualified. Otherwise, calculate the quality index according to relevant information: ； Among them, is the quality index, is the flame retardancy performance index, is the flame retardancy performance weight, is the pollution performance index, is the pollution performance weight. When the quality index of the cable is greater than the set threshold, the cable is considered qualified; otherwise, the cable is considered unqualified. For and can be obtained according to the following steps: STEP1. Collect various data obtained during combustion at multiple combustion grades; STEP2. Fit the data through the following fitting equation: ； ； Wherein, is the temperature value corresponding to the combustion level between the start of combustion and intense combustion, is the total concentration of harmful gases generated by the cable to be detected under the condition of , is the temperature value corresponding to the combustion level between the combustion level corresponding to intense combustion and the maximum combustion level, is the total concentration of harmful gases generated by the cable to be detected under the condition of , and are constants; STEP3, Obtain the and values according to the fitting results; For and can be obtained according to the following formula: ； ； Among them, is the toxicity threshold of the i-th harmful gas to the human body, is the toxicity threshold of the j-th harmful gas to the human body, The number of atoms contained in the molecule corresponding to the j-th harmful gas, is the number of atoms belonging to halogens contained in the molecule corresponding to the j-th harmful gas.

2. The manufacturing method of an environment-friendly low-smoke and halogen-free cable according to claim 1, characterized in that The raw materials of the insulating layer of the cable include zinc borate, polyphosphazene flame retardant, smoke suppressant inorganic flame retardant, polymer substrate, antioxidant and anti-irradiation agent.

3. The manufacturing method of an environment-friendly low-smoke and halogen-free cable according to claim 2, characterized in that, The components of the raw material of the protective sleeve of the cable by weight are: 5-6 parts of saturated polyester, 14-16 parts of high polystyrene, 2-3 parts of stearic acid, 6-8 parts of ferric oxide, 3-4 parts of aluminum silicate, 8-10 parts of polyurethane, 1-3 parts of triethylenediamine, 2-4 parts of phosphogypsum, 2-3 parts of methyl silicone oil, 2-5 parts of silicone and 48-52 parts of ethylene-propylene rubber.

4. The manufacturing method of an environment-friendly low-smoke and halogen-free cable according to claim 3, characterized in that, The diameter of the cable is 50 mm, the thickness of the protective sleeve is 8 mm, the outer surface of the protective sleeve includes a plurality of adjacent protrusions, the grooves between the protrusions are used for injecting insect repellent substances, and the depth of the grooves is 4 mm.

5. The manufacturing method of an environment-friendly low-smoke and halogen-free cable according to claim 4, characterized in that, It also includes a cable manufacturing system, including a raw material storage module, a cable production module, a cable quality detection module, and a data analysis module; the raw material storage module is used to store the raw materials for manufacturing the cable; the cable production module includes a robotic arm, a conveyor belt, an extruder and a braiding machine, the robotic arm is used to extract the raw materials from the raw material storage module and place them on the conveyor belt, the conveyor belt is used to transport the raw materials to the extruder, the extruder is used to extrude and form each layer of the cable, and the braiding machine is used to braid the shielding layer of the cable; the cable quality detection module includes a fire source, a temperature detection unit, a gas detection unit, a weight detection unit and a timing unit, the fire source is used to burn the cable, the temperature detection unit is used to detect the combustion temperature, the gas detection unit is used to detect the types and concentrations of gases generated during the combustion process, the weight detection unit is used to detect the remaining weight of the cable after combustion, and the timing unit is used to time during the quality detection process; the data analysis module includes a data acquisition module, a calculation module and a comparison module, the data acquisition module is used to collect various parameters of the cable quality detection module, the calculation module is used to calculate the quality index of the cable, and the comparison module is used to compare the quality index of the cable with a set threshold to determine whether the quality of the cable is qualified.

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