Heating wire and preparation method thereof
By using a heating wire structure made of high-conductivity aluminum alloy wire and intelligent temperature-controlled electric heating material, the existing heating wires have been solved, and a lightweight heating wire with low cost and excellent safety performance has been achieved.
Patent Information
- Application Number
- CN202411689737.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-25
- Publication Date
- 2025-02-28
AI Technical Summary
The conductivity of the alloy resistive wires in existing heating wires is insufficient, resulting in heavy quality of heating devices and high production costs, making it difficult to meet the lightweight design requirements.
The heating wire structure is adopted including a core wire, a self-limited temperature electric heating layer and a cable insulation layer. The core wire is an aluminum alloy wire with high conductivity. The self-limited temperature electric heating layer is made of an electric heating material with intelligent temperature control function, and the cable insulation layer is PVC, TPU or TPEE material. The resistance and power of the heating wire are regulated by controlling the conductivity and cross-sectional area of the core wire and the self-limiting temperature electric heating layer.
It realizes heating wires with low production costs and excellent safety performance, and the self-limiting temperature-electric heating layer emits far-infrared heating, shields the core wire electromagnetic radiation, and meets the lightweight design requirements.
Smart Images
Figure CN119545587A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of heating wire preparation, and in particular to a heating wire and a preparation method thereof. Background Art
[0002] Heating wires, also known as heating cables, use electricity as energy and use alloy resistance wires to generate heat to achieve the effect of heating or insulation. The alloy resistance wires in heating wires in the prior art are usually copper wires or nickel-plated copper wires. The advantages of copper wires are: their excellent electrical conductivity. Under the same power, copper wires can meet the power requirements of heating devices at a thinner diameter than nickel-plated copper wires. However, their mechanical strength is relatively low and their flexural resistance is poor, which limits their scope of use and application. In addition, the price of pure copper wires is relatively high, resulting in a relatively high production cost of the prepared heating devices, and they are gradually replaced by nickel-plated copper wires with better economics.
[0003] Although nickel-plated copper wire can improve the mechanical strength and flexural resistance to a certain extent, its electrical conductivity is relatively poor. Under the same power, the diameter of the nickel-plated copper wire needs to be larger, resulting in a heavier mass of the heating device, which is not conducive to the lightweight design of the heating device. To this end, the inventor provides a heating wire with low production cost and safe use and a preparation method thereof. Summary of the invention
[0004] In order to solve the problems existing in the prior art, the present application provides a heating wire and a preparation method thereof.
[0005] The present application provides a heating wire which is realized by the following technical solutions: A heating wire, comprising a core wire, a self-limiting temperature electric heating layer coated on the outer wall of the core wire, and a cable insulation layer coated on the outer wall of the self-limiting temperature electric heating layer, wherein the core wire is any one of pure copper wire, copper alloy wire, nickel-plated copper wire, aluminum alloy wire, aluminum / copper / aluminum composite wire, and copper-plated aluminum alloy wire; the self-limiting temperature electric heating layer is made of an electric heating material with an intelligent temperature control function; the cable insulation layer is any one of a PVC insulation layer, a TPU insulation layer, and a TPEE insulation layer; the conductivity ρ1 of the core wire is 75-102% IACS; The resistance R1 of the core wire = ρ1*L1 / S1, ρ1 is the conductivity of the core wire, L1 is the length of the core wire, and S1 is the cross-sectional area of the core wire; the resistance R2 of the self-limiting temperature electric heating layer = ρ2*L2 / S2, ρ2 is the conductivity of the self-limiting temperature electric heating layer, L2 is the length of the self-limiting temperature electric heating layer, and S2 is the cross-sectional area of the self-limiting temperature electric heating layer; the resistance R of the heating wire can be adjusted by controlling the conductivity ρ1 and the cross-sectional area S1 of the core wire 总 and power P, and the resistance R of the heating wire can be adjusted by controlling the conductivity ρ1 and cross-sectional area S1 of the self-limiting temperature electric heating layer 总 and power P.
[0006] Compared with the existing soft copper wire and nickel-plated copper wire, the heating wire provided in the present invention not only has a relatively low production cost, but also has better safety performance. At the same time, the self-limiting temperature electric heating layer emits far-infrared heating, which can act as a shielding layer, greatly weakening the electromagnetic radiation generated by the core wire, reducing the overall production cost, and meeting the lightweight design requirements.
[0007] Preferably, the electrical conductivity ρ1 of the core wire is 75-90% IACS, and the core wire is a high-strength and high-conductivity aluminum alloy wire with a diameter of 80-120 microns.
[0008] Preferably, the mass percentages of the elements in the aluminum alloy wire are as follows: 0.40-1.2wt% of nano-aluminum clusters @ single-walled carbon nanotubes, 0.10-0.30wt% of Mg, 0.05-0.30wt% of Fe, 0.10-0.30wt% of Cu, 0.10-0.20wt% of Si, 0.05-0.20wt% of Mn, 0.05-0.20wt% of Zr, 0.004-0.012wt% of La, 0.004-0.008 of Y, 0.01-0.04wt% of Ag, the total content of unavoidable impurities is <0.10%, and the balance is Al.
[0009] The aluminum alloy wire prepared by the above aluminum alloy wire formula has good electrical conductivity and excellent mechanical strength and flexural resistance. The heating wire prepared by the above aluminum alloy wire formula also has excellent mechanical strength and flexural resistance. In addition, the production cost of aluminum alloy wire is much lower than that of copper wire and copper alloy wire, which can effectively reduce the overall production cost.
[0010] Preferably, the electric heating material with intelligent temperature control function is prepared from the following raw materials in mass percentage: 10.0-40.0% of a conductive composition, 6.0-12.0% of a reinforcing agent for silk thread, 1.20-1.80% of an antioxidant composition, 0.20-0.40% of an anti-ultraviolet agent, 0.10-0.30% of a dispersant, and the remainder is a matrix resin; the matrix resin is composed of PP resin, HDPE resin, and EVA resin; the conductivity ρ2 of the self-limiting temperature electric heating layer prepared from the electric heating material with intelligent temperature control function is 44.27-2.27*10 4 Ω*mm 2 / m, the cross-sectional area S2 of the self-limiting temperature electric heating layer is 0.8-3.2mm 2 .
[0011] The self-limiting temperature electric heating layer prepared by the above-mentioned electric heating material formula with intelligent temperature control function can not only flexibly adjust the conductivity of the self-limiting temperature electric heating layer, and then accurately control the overall resistance and rated power of the heating wire, but also effectively improve the mechanical strength, heat resistance and flexibility of the self-limiting temperature electric heating layer.
[0012] Preferably, the matrix resin is composed of PP resin, EVA resin and HDPE resin in a mass ratio of (78-82):(18-22):(36-44).
[0013] By adopting the above technical solution, the self-limiting temperature electric heating layer is endowed with good self-limiting temperature function.
[0014] Preferably, the conductive composition is composed of the following raw materials in percentage by weight: 5.0-20wt% of nano titanium diboride, 1.0-10wt% of multi-walled carbon nanotubes, 1.0-10wt% of highly conductive graphene, 0.5-5wt% of titanium nitride whiskers, and the balance is nano carbon black; the nano titanium diboride has an average particle size of 0.05-30μm and a hexagonal crystal form; the multi-walled carbon nanotube has a diameter of 5-50μm, a purity of >95w%, and a SSA of >110m 2 / g, ash content <5.0wt%; the number of layers of the highly conductive graphene is <5, purity >99w%, sheet diameter 0.2-0.5μm, SSA>300m 2 / g, ash content <1wt%.
[0015] By adopting the above technical scheme, the conductivity of the self-limiting temperature electric heating layer can be flexibly adjusted, thereby accurately controlling the overall resistance and rated power of the heating wire. It can also assist in improving the mechanical strength, heat resistance, flexibility and flame retardancy of the self-limiting temperature electric heating layer, thereby ensuring the overall safety of the heating wire.
[0016] Preferably, the reinforcing agent for the silk thread is mainly composed of nano zinc oxide, nano zirconium oxide, nano silicon nitride and boron nitride nano sheets; the mass ratio of the nano zinc oxide, nano zirconium oxide, nano silicon nitride and boron nitride nano sheets is controlled at (55-90):(5-20):(5-20):(0.5-5).
[0017] By adopting the above technical solution, the mechanical strength, heat resistance, flexibility and flame retardancy of the self-limiting temperature electric heating layer can be improved, thereby ensuring the overall safety performance of the heating wire.
[0018] Preferably, the cable further comprises a reinforcing alloy wire spirally wound around the outer wall of the self-limiting temperature electric heating layer, wherein the reinforcing alloy wire is located between the self-limiting temperature electric heating layer and the cable insulation layer; The resistance of the reinforced alloy wire is R3=ρ3*L3 / S3, where ρ3 is the electrical conductivity of the reinforced alloy wire, L3 is the length of the reinforced alloy wire, and S3 is the cross-sectional area of the reinforced alloy wire; The pitch of the reinforced alloy wire is D, then the length of the reinforced alloy wire is L3 2 =D 2 +S4 2 , S4 is the circumference of the self-limiting temperature electric heating layer, that is, S4=2πr, r is the outer diameter of the self-limiting temperature electric heating layer; The resistance R of the heating wire can be adjusted by controlling the conductivity ρ1 and the cross-sectional area S1 of the core wire. 总 and power P, and the resistance R of the heating wire can be adjusted by controlling the conductivity ρ1 and cross-sectional area S1 of the self-limiting temperature electric heating layer 总 and power P. In addition, the resistance R of the heating wire can be adjusted by controlling the conductivity ρ3 and cross-sectional area S3 of the enhanced alloy wire. 总 and power P.
[0019] By adopting the above technical solution, the overall resistance of the heating wire can be further reduced, thereby increasing the power P of the heating wire, thereby increasing the application range of the heating wire and the abundance of heating wire products.
[0020] The present application provides a method for preparing a heating wire, which is achieved through the following technical solutions: A method for preparing a heating wire without a reinforcing alloy wire comprises the following steps: Step 1: Preparation of electric heating materials with intelligent temperature control function; Step 2, placing the spinning masterbatch in a twin-screw extruder for melt extrusion, the obtained extruded molten material is attached to the outer surface of the core wire, and water-cooling, heat treatment, and drying are performed to obtain a semi-finished heating wire; Step three, placing the polymer insulating resin in a twin-screw extruder for melt extrusion, and the resulting extruded molten material is attached to the outer surface of the semi-finished heating wire, and the finished heating wire is obtained by water cooling, heat treatment, drying, and winding.
[0021] A method for preparing a heating wire comprising a reinforced alloy wire comprises the following steps: Step 1: Preparation of electric heating materials with intelligent temperature control function; Step 2, placing the spinning masterbatch in a twin-screw extruder for melt extrusion, the obtained extruded molten material is attached to the outer surface of the core wire, and water-cooling, heat treatment, and drying are performed to obtain a semi-finished heating wire; Step 3, spirally winding the reinforced alloy wire around the outer wall of the semi-finished heating wire to obtain the primary heating wire; Step 4: Place the polymer insulating resin in a twin-screw extruder for melt extrusion, and the resulting extruded molten material is attached to the outer surface of the primary heating wire. The finished heating wire can be obtained by water cooling, heat treatment, drying, and winding.
[0022] The preparation method of the present application is relatively simple, has low operating difficulty, and is easy to implement industrial production and manufacturing.
[0023] In summary, this application has the following advantages: 1. Compared with the existing soft copper wire and nickel-plated copper wire, the heating wire provided in the present invention not only has a relatively low production cost, but also has a self-limiting temperature function and better safety performance in use.
[0024] 2. The self-limiting temperature electric heating layer of the present invention emits far-infrared heating, which can play the role of a shielding layer, greatly weakening the electromagnetic radiation generated by the core wire, reducing the overall production cost, and meeting the lightweight design requirements.
[0025] 3. The preparation method of the present application is relatively simple, has low operating difficulty, and is easy to implement industrial production. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Figure 1 It is a schematic diagram of the overall structure of the embodiment of the present invention without the reinforced alloy wire heating wire.
[0027] Figure 2 It is a schematic diagram of the overall structure including the reinforced alloy wire heating wire in an embodiment of the present invention.
[0028] In the figure, 1. core wire; 2. self-limiting temperature electric heating layer; 3. cable insulation layer; 4. reinforced alloy wire. DETAILED DESCRIPTION
[0029] In order to further understand the present invention, preferred embodiments of the present invention are described below in conjunction with examples and comparative examples.
[0030] Preparation Example 1: The mass percentages of elements in the aluminum alloy wire are as follows: 0.40% nano-aluminum clusters @ single-walled carbon nanotubes (commercially available, prepared by a sol-gel method from Guangzhou Zhongshan Functional Materials Co., Ltd., with a loading rate of 6.08wt% of nano-aluminum clusters), 0.18wt% Mg, 0.16wt% Fe, 0.24wt% Cu, 0.16wt% Si, 0.08wt% Mn, 0.06wt% Zr, 0.008wt% La, 0.004 Y, 0.024wt% Ag, the total content of unavoidable impurities <0.10%, and the balance is Al.
[0031] The preparation method of aluminum alloy wire is as follows: S1. According to the element formula of the mass percentage of the above aluminum alloy wire, accurately measured electrolytic aluminum ingots, magnesium ingots, aluminum silicon alloys, aluminum copper alloys, aluminum iron alloys, aluminum zirconium alloys, aluminum lanthanum alloys, aluminum manganese alloys, aluminum yttrium alloys, and aluminum silver alloys are put into a smelting furnace, and the temperature is raised to 700°C at 20°C / min and kept for 15 minutes. The slag floating on the liquid surface should be removed in time, and the chemical composition should be analyzed by spectrometer measurement. The measurement results are compared with the proportion of ingredients, and adjustments are made as appropriate until they are qualified, and then nano-aluminum clusters @ single-walled carbon nanotubes are added, and after stirring at 240rpm for 15 minutes, refining is performed: zinc chloride is added, and the amount of zinc chloride added is 2.4wt% of the alloy mass, and refined at 700°C for 15 minutes, chlorine gas is blown, and the air pressure is 0.15MPa. The aluminum alloy melt is degassed and deslag is removed to obtain the aluminum alloy melt, and the obtained aluminum alloy melt is cast into an aluminum rod mold, and after water cooling to room temperature, a semi-finished aluminum rod embryo is obtained, and the diameter of the obtained semi-finished aluminum rod embryo is 12.0mm; S2. The semi-finished aluminum billet is placed in a muffle furnace and heated to a solution temperature of 485°C at 10°C / min and kept at that temperature for 60 minutes. It is then air-cooled to room temperature at 25°C / min and kept at that temperature for 15 minutes. It is then heated to an aging temperature of 165°C at 5°C / min and kept at that temperature for 180 minutes. It is then heated to 565°C at 10°C / min and molded into a finished aluminum billet with a diameter of 8 mm. S3. The finished aluminum rod blank is subjected to multi-stage wire drawing processing: specifically, the temperature is raised to 565°C at 10°C / min and input into the extrusion die for primary wire drawing, the angle α of the extrusion die is 30°, the temperature is lowered to 360°C after primary wire drawing and kept warm for 120min for annealing treatment, and a 4mm diameter aluminum alloy rod is obtained; then the temperature is raised to 565°C at 10°C / min and input into the extrusion die for secondary wire drawing, the angle α of the extrusion die is 30°, the temperature is lowered to 360°C after secondary wire drawing and kept warm for 120min for annealing treatment, and a 2mm diameter aluminum alloy is obtained. The rod was then heated to 565°C at 10°C / min and fed into an extrusion die for three-stage wire drawing. The angle α of the extrusion die was 30°. After the three-stage wire drawing, the temperature was lowered to 360°C and kept for 120 min for annealing to obtain an aluminum alloy rod with a diameter of 1 mm. The rod was then heated to 565°C at 10°C / min and fed into an extrusion die for four-stage wire drawing. The angle α of the extrusion die was 30°. After the four-stage wire drawing, the temperature was lowered to 360°C and kept for 120 min for annealing to obtain an aluminum alloy wire with a diameter of 0.5 mm. The electrical conductivity of the obtained aluminum alloy wire was 76.2%IACS (converted to 44.20MS / m, 2.26265*10 -8 Ω*mm 2 / m), tensile strength 128.4 MPa, and elongation at break 14.9%.
[0032] The difference between Preparation Example 2 and Preparation Example 1 is that the weight percentage of the elements in the aluminum alloy wire is as follows: 0.8wt% of nano-aluminum clusters @ single-walled carbon nanotubes, 0.18wt% of Mg, 0.16wt% of Fe, 0.24wt% of Cu, 0.16wt% of Si, 0.08wt% of Mn, 0.06wt% of Zr, 0.008wt% of La, 0.004 of Y, 0.024wt% of Ag, the total content of unavoidable impurities <0.10%, and the balance is Al. The conductivity of the obtained aluminum alloy wire is 83.2% IACS (converted to 48.26MS / m, 2.07211*10 -8 Ω*mm 2 / m), tensile strength 135.7 MPa, and elongation at break 13.7%.
[0033] The difference between Preparation Example 3 and Preparation Example 1 is that the weight percentage of the elements in the aluminum alloy wire is as follows: 1.2wt% of nano-aluminum clusters @ single-walled carbon nanotubes, 0.18wt% of Mg, 0.16wt% of Fe, 0.24wt% of Cu, 0.16wt% of Si, 0.08wt% of Mn, 0.06wt% of Zr, 0.008wt% of La, 0.004 of Y, 0.024wt% of Ag, the total content of unavoidable impurities <0.10%, and the balance is Al. The conductivity of the obtained aluminum alloy wire is 89.5% IACS (converted to 51.91MS / m, 1.92641*10 -8 Ω*mm 2 / m), tensile strength 141.3 MPa, and elongation at break 13.1%.
[0034] Preparation Example 4: The electric heating material with intelligent temperature control function is prepared from the following raw materials in the following mass percentages: 10.0% of a conductive composition, 6.0% of a reinforcing agent for silk thread, 1.60% of an antioxidant composition, 0.40% of an anti-ultraviolet agent, 0.20% of a dispersant, and the remainder is a base resin.
[0035] The matrix resin is composed of PP resin (Yangzi Petrochemical K8003), EVA resin (Formosa EVA 7340M, VA content: 28wt%), and HDPE resin (Formosa HDPE 8001) in a mass ratio of 795:185:420.
[0036] The conductive composition is composed of the following raw materials in percentage by mass: 15wt% of nano titanium diboride, 5wt% of multi-walled carbon nanotubes, 3wt% of high-conductive graphene, 2wt% of titanium nitride whiskers, and the balance is nano carbon black.
[0037] The nano carbon black is Bot conductive carbon black VXC72.
[0038] Nano titanium diboride, commercially available titanium diboride is planetary ball milled to an average particle size of 0.5-1 micron, hexagonal crystal.
[0039] The diameter of multi-walled carbon nanotubes is 10-20μm, purity>95w%, SSA>110m 2 / g, ash content <5.0wt%, industrial-grade multi-walled carbon nanotubes IMWCNTs from Chengdu Organic Chemistry Co., Ltd., Chinese Academy of Sciences.
[0040] The number of layers of highly conductive graphene is <5, purity is >99w%, sheet diameter is 0.2-0.5μm, SSA>300m 2 / g, ash content <1wt%, TNHRGO highly conductive graphene from Chengdu Organic Chemistry Co., Ltd., Chinese Academy of Sciences.
[0041] The reinforcing agent for silk thread is composed of nano zinc oxide (average particle size 500nm, spherical crystal), nano zirconium oxide (average particle size 200nm, cubic crystal), nano silicon nitride (average particle size 800nm, face-centered cubic crystal), and boron nitride nanosheets (average particle size 500nm, hexagonal crystal) in a mass ratio of 80:10:8:2.
[0042] The antioxidant composition is composed of antioxidant 1024 and antioxidant 697 in a mass ratio of 3:2.
[0043] The anti-ultraviolet additives are composed of UV-531 and UV-622 in a mass ratio of 3:2.
[0044] The dispersant is zinc stearate.
[0045] Preparation method of electric heating masterbatch with intelligent temperature control function: S1. After the accurately measured conductive composition, reinforcing agent for silk thread, antioxidant composition, anti-ultraviolet additive dispersant and base resin are dispersed at 400 rpm for 4 hours, the resulting mixture is placed in an internal mixer to mix evenly and then internally kneaded at a temperature of 165°C for 300 seconds; S2. The mixed material obtained in S1 is placed in a twin-screw extruder for melt extrusion at a temperature of 175-195°C, which is specifically divided into five heating temperature zones, the first temperature zone is 170°C±0.5°C, the second temperature zone is 180°C±0.5°C, the third temperature zone is 190°C±0.5°C, the fourth temperature zone is 195°C±0.5°C, the fifth temperature zone is 195°C±0.5°C, the screw speed is 38r / min, the die temperature is 193.6°C, wire drawing, water cooling, and granulation are performed to obtain 1.0-1.2mm spinning masterbatch, which is dried to a moisture content of ≤0.10wt% and set aside.
[0046] The difference between Preparation Example 5 and Preparation Example 4 is that the electric heating material with intelligent temperature control function is made of the following raw materials in the following mass percentages: 15% of a conductive composition, 6.0% of a reinforcing agent for silk thread, 1.60% of an antioxidant composition, 0.40% of an anti-ultraviolet agent, 0.20% of a dispersant, and the remainder is a base resin.
[0047] The difference between Preparation Example 6 and Preparation Example 4 is that the electric heating material with intelligent temperature control function is made of the following raw materials in the following mass percentages: 20% of a conductive composition, 6.0% of a reinforcing agent for silk thread, 1.60% of an antioxidant composition, 0.40% of an anti-ultraviolet agent, 0.20% of a dispersant, and the remainder is a base resin.
[0048] The difference between Preparation Example 7 and Preparation Example 4 is that the electric heating material with intelligent temperature control function is made of the following raw materials in the following mass percentages: 25% of a conductive composition, 6.0% of a reinforcing agent for silk thread, 1.60% of an antioxidant composition, 0.40% of an anti-ultraviolet agent, 0.20% of a dispersant, and the remainder is a base resin.
[0049] The difference between Preparation Example 8 and Preparation Example 4 is that the electric heating material with intelligent temperature control function is made of the following raw materials in the following mass percentages: 30% of a conductive composition, 6.0% of a reinforcing agent for silk thread, 1.60% of an antioxidant composition, 0.40% of an anti-ultraviolet agent, 0.20% of a dispersant, and the remainder is a base resin.
[0050] The difference between Preparation Example 9 and Preparation Example 4 is that the electric heating material with intelligent temperature control function is made of the following raw materials in the following mass percentages: 40% of a conductive composition, 6.0% of a reinforcing agent for silk thread, 1.60% of an antioxidant composition, 0.40% of an anti-ultraviolet agent, 0.20% of a dispersant, and the remainder is a base resin.
[0051] Table 1 is a table of conductivity test parameters of the electric heating masterbatch with intelligent temperature control function in Preparation Examples 4-9 Example
[0052] refer to Figure 1 A heating wire comprises a core wire 1, a self-limiting temperature electric heating layer 2 coated on the outer wall of the core wire 1, and a cable insulation layer 3 coated on the outer wall of the self-limiting temperature electric heating layer 2. The core wire 1 is any one of pure copper wire, copper alloy wire, nickel-plated copper wire, aluminum alloy wire, aluminum / copper / aluminum composite wire, and copper-plated aluminum alloy wire. The self-limiting temperature electric heating layer 2 is made of an electric heating material with an intelligent temperature control function. The cable insulation layer 3 is any one of a PVC insulation layer, a TPU insulation layer, and a TPEE insulation layer.
[0053] The electrical conductivity ρ1 of the core 1 is 75-102 %IACS.
[0054] The resistance of the core wire 1 is R1=ρ1*L1 / S1, ρ1 is the conductivity of the core wire 1, L1 is the length of the core wire 1, and S1 is the cross-sectional area of the core wire 1.
[0055] The resistance R2 of the self-limiting temperature electric heating layer 2 = ρ2*L2 / S2, ρ2 is the conductivity of the self-limiting temperature electric heating layer 2, L2 is the length of the self-limiting temperature electric heating layer 2, and S2 is the cross-sectional area of the self-limiting temperature electric heating layer 2.
[0056] The resistance R of the heating wire can be adjusted by controlling the conductivity ρ1 and the cross-sectional area S1 of the core wire 1. 总 and power P, and the resistance R of the heating wire can be adjusted by controlling the conductivity ρ1 and cross-sectional area S1 of the self-limiting temperature electric heating layer 2 总 And power P.
[0057] Preferably, the electrical conductivity ρ1 of the core wire 1 is 75-90% IACS, and the core wire 1 is a high-strength and high-conductivity aluminum alloy wire with a diameter of 80-120 microns.
[0058] The elements in the aluminum alloy wire by mass percentage are as follows: 0.40-1.2wt% of nano-aluminum clusters @ single-walled carbon nanotubes, 0.10-0.30wt% of Mg, 0.05-0.30wt% of Fe, 0.10-0.30wt% of Cu, 0.10-0.20wt% of Si, 0.05-0.20wt% of Mn, 0.05-0.20wt% of Zr, 0.004-0.012wt% of La, 0.004-0.008 of Y, 0.01-0.04wt% of Ag, the total content of unavoidable impurities is <0.10%, and the balance is Al.
[0059] The electric heating material with intelligent temperature control function is prepared from the following raw materials in the following mass percentages: the electric heating material with intelligent temperature control function is prepared from the following raw materials in the following mass percentages: 10.0-40.0% of a conductive composition, 6.0-12.0% of a reinforcing agent for silk thread, 1.20-1.80% of an antioxidant composition, 0.20-0.40% of an anti-ultraviolet agent, 0.10-0.30% of a dispersant, and the remainder is a base resin.
[0060] The matrix resin is composed of PP resin, HDPE resin and EVA resin. Preferably, the matrix resin is composed of PP resin, EVA resin and HDPE resin in a mass ratio of (78-82):(18-22):(36-44).
[0061] The conductivity ρ2 of the self-limiting temperature electric heating layer 2 prepared by the electric heating material with intelligent temperature control function is 44.27~2.27*104 Ω*mm 2 / m, the cross-sectional area S2 of the self-limiting temperature electric heating layer 2 is 0.8~3.2mm 2 .
[0062] The conductive composition is composed of the following raw materials in percentage by mass: 5.0-20wt% of nano titanium diboride, 1.0-10wt% of multi-walled carbon nanotubes, 1.0-10wt% of highly conductive graphene, 0.5-5wt% of titanium nitride whiskers, and the balance is nano carbon black.
[0063] The average particle size of nano titanium diboride is 0.05-30 μm, and it has a hexagonal crystal form.
[0064] Nano graphite powder is flaky graphite powder with an average particle size of 0.2-1.0μm.
[0065] The diameter of multi-walled carbon nanotubes is 5-50μm, purity>95w%, SSA>110m 2 / g, ash content <5.0wt%.
[0066] The number of layers of highly conductive graphene is <5, purity is >99w%, sheet diameter is 0.2-0.5μm, SSA>300m 2 / g, ash content <1wt%.
[0067] The reinforcing auxiliary agent for silk thread is composed of nano zinc oxide, nano zirconium oxide, nano silicon nitride and boron nitride nano sheets in a mass ratio of (55-90):(5-20):(5-20):(0.5-5).
[0068] A method for preparing a heating wire comprises the following steps: Step 1: Preparation of electric heating materials with intelligent temperature control function; Step 2, placing the spinning masterbatch in a twin-screw extruder for melt extrusion, and the resulting extruded molten material is attached to the outer surface of the core wire 1, and water-cooling, heat treatment, and drying are performed to obtain a semi-finished heating wire; Step three, placing the polymer insulating resin in a twin-screw extruder for melt extrusion, and the resulting extruded molten material is attached to the outer surface of the semi-finished heating wire, and the finished heating wire is obtained by water cooling, heat treatment, drying, and winding.
[0069] refer to Figure 2 In order to improve the heating performance of the heating wire, the heating wire also includes a reinforced alloy wire 4 spirally wound around the outer wall of the self-limiting temperature electric heating layer 2, and the reinforced alloy wire 4 is located between the self-limiting temperature electric heating layer 2 and the cable insulation layer 3.
[0070] The resistance R3 of the reinforcement alloy wire 4 is R3=ρ3*L3 / S3, where ρ3 is the electrical conductivity of the reinforcement alloy wire 4, L3 is the length of the reinforcement alloy wire 4, and S3 is the cross-sectional area of the reinforcement alloy wire 4.
[0071] The pitch of the reinforcing alloy wire 4 is D, and the length L3 of the reinforcing alloy wire 4 is 2 =D 2 +S4 2 , S4 is the circumference of the self-limiting temperature electric heating layer 2, that is, S4=2πr, r is the outer diameter of the self-limiting temperature electric heating layer 2.
[0072] The resistance R of the heating wire can be adjusted by controlling the conductivity ρ1 and the cross-sectional area S1 of the core wire 1. 总 and power P, and the resistance R of the heating wire can be adjusted by controlling the conductivity ρ1 and cross-sectional area S1 of the self-limiting temperature electric heating layer 2 总 and power P. In addition, the resistance R of the heating wire can be adjusted by controlling the conductivity ρ3 and cross-sectional area S3 of the enhanced alloy wire 4. 总 and power P.
[0073] A method for preparing a heating wire comprises the following steps: Step 1: Preparation of electric heating materials with intelligent temperature control function; Step 2, placing the spinning masterbatch in a twin-screw extruder for melt extrusion, and the resulting extruded molten material is attached to the outer surface of the core wire 1, and water-cooling, heat treatment, and drying are performed to obtain a semi-finished heating wire; Step 3, spirally winding the reinforced alloy wire around the outer wall of the semi-finished heating wire to obtain the primary heating wire; Step 4: Place the polymer insulating resin in a twin-screw extruder for melt extrusion, and the resulting extruded molten material is attached to the outer surface of the primary heating wire. The finished heating wire can be obtained by water cooling, heat treatment, drying, and winding.
[0074] Embodiment 1: A heating wire comprises a core wire 1 , a self-limiting temperature electric heating layer 2 coated on the outer wall of the core wire 1 , and a cable insulation layer 3 coated on the outer wall of the self-limiting temperature electric heating layer 2 .
[0075] Core wire 1 is pure copper wire, diameter 0.50mm, conductivity ρ1=1.72414*10 -8 Ω*mm 2 / m.
[0076] The self-limiting temperature electric heating layer 2 is prepared from the electric heating masterbatch with intelligent temperature control function in Preparation Example 4, and the prepared self-limiting temperature electric heating layer 2 has an outer diameter of 1.5 mm.
[0077] The cable insulation layer 3 is a PVC insulation layer with an outer diameter of 2.5 mm.
[0078] A method for preparing a heating wire comprises the following steps: Step 1: Preparation of an electric heating material with intelligent temperature control function, see Preparation Example 4; Step 2: Use pure copper wire (diameter 0.50mm, conductivity ρ1=1.72414*10 -8 Ω*mm 2 / m) as the core wire, the spinning masterbatch is placed in a twin-screw extruder, the extrusion temperature is 175-195℃, and it is specifically divided into five heating temperature zones, the first temperature zone is 170℃±0.5℃, the second temperature zone is 180℃±0.5℃, the third temperature zone is 190℃±0.5℃, the fourth temperature zone is 195℃±0.5℃, the fifth temperature zone is 195℃±0.5℃, the screw speed is 38r / min, the die head temperature is 193.5℃, the extruded molten material is attached to the outer surface of the pure copper wire, the traction speed is 6.4cm / s, water cooling and heat treatment: the semi-finished yarn after water cooling is placed in a 60℃ oven for a stroke of 3.6m, enters an 80℃ oven for a stroke of 5.4m, enters a 60℃ oven for a stroke of 3.6m, and air-cooled at room temperature for a stroke of 5.4m to obtain a semi-finished electric heating wire, and the outer diameter of the self-limiting temperature electric heating layer 2 is 1.5mm; Step three, placing the PVC resin in a twin-screw extruder for melt extrude, the extrusion temperature is 185-215°C, specifically divided into five heating temperature zones, the first temperature zone is 185°C±0.5°C, the second temperature zone is 195°C±0.5°C, the third temperature zone is 210°C±0.5°C, the fourth temperature zone is 215°C±0.5°C, the fifth temperature zone is 215°C±0.5°C, the screw speed is 42r / min, the die head temperature is 209.8°C, the obtained extruded molten material is attached to the outer surface of the semi-finished heating wire, and the finished heating wire can be obtained by water cooling, heat treatment, drying and winding.
[0079] The difference between Example 2 and Example 1 is that the core wire 1 is the aluminum alloy wire in Preparation Example 1, with a diameter of 0.50 mm and a conductivity of ρ1=2.26265*10 -8 Ω*mm 2 / m.
[0080] The difference between Example 3 and Example 1 is that the core wire 1 is the aluminum alloy wire in Preparation Example 2, with a diameter of 0.50 mm and a conductivity of ρ1=2.07211*10 -8 Ω*mm 2 / m.
[0081] The difference between Example 4 and Example 1 is that the core wire 1 is the aluminum alloy wire in Preparation Example 3, with a diameter of 0.50 mm and a conductivity of ρ1=1.92641*10 -8 Ω*mm 2 / m.
[0082] The difference between Example 5 and Example 4 is that the self-limiting temperature electric heating layer 2 is prepared from the electric heating masterbatch with intelligent temperature control function in Preparation Example 5, and the prepared self-limiting temperature electric heating layer 2 has an outer diameter of 1.5 mm.
[0083] The difference between Example 6 and Example 1 is that the self-limiting temperature electric heating layer 2 is prepared from the electric heating masterbatch with intelligent temperature control function in Preparation Example 6, and the prepared self-limiting temperature electric heating layer 2 has an outer diameter of 1.5 mm.
[0084] The difference between Example 7 and Example 1 is that the self-limiting temperature electric heating layer 2 is prepared from the electric heating masterbatch with intelligent temperature control function in Preparation Example 7, and the prepared self-limiting temperature electric heating layer 2 has an outer diameter of 1.5 mm.
[0085] The difference between Example 8 and Example 1 is that the self-limiting temperature electric heating layer 2 is prepared from the electric heating masterbatch with intelligent temperature control function in Preparation Example 8, and the prepared self-limiting temperature electric heating layer 2 has an outer diameter of 1.5 mm.
[0086] The difference between Example 9 and Example 1 is that the self-limiting temperature electric heating layer 2 is prepared from the electric heating masterbatch with intelligent temperature control function in Preparation Example 9, and the prepared self-limiting temperature electric heating layer 2 has an outer diameter of 1.5 mm.
[0087] The difference between Example 10 and Example 9 is that a heating wire includes a core wire 1, a self-limiting temperature electric heating layer 2 wrapped on the outer wall of the core wire 1, a reinforced alloy wire 4 spirally wound on the outer wall of the self-limiting temperature electric heating layer 2, and a cable insulation layer 3 wrapped on the outer wall of the self-limiting temperature electric heating layer 2. It should be noted that the reinforced alloy wire 4 is located between the self-limiting temperature electric heating layer 2 and the cable insulation layer 3, and the pitch is 3mm. The core wire 1 is the aluminum alloy wire in Preparation Example 3, with a diameter of 0.50mm and a conductivity of ρ1=1.92641*10 -8 Ω*mm 2 / m. The reinforced alloy wire 4 is a pure copper wire with a diameter of 0.15 mm and a conductivity of ρ1 = 1.72414*10 -8 Ω*mm 2 / m. The self-limiting temperature electric heating layer 2 is prepared from the electric heating masterbatch with intelligent temperature control function in Preparation Example 4, and the prepared self-limiting temperature electric heating layer 2 has an outer diameter of 1.5mm. The cable insulation layer 3 is a PVC insulation layer with an outer diameter of 2.5mm.
[0088] The difference between Comparative Example 1 and Example 1 is that the core wire 1 is a carbon fiber wire of Toray T300 1K. The difference in the preparation method of the heating wire is: Step 2, using Toray T300 1K carbon fiber wire as the core wire, placing the spinning masterbatch in a twin-screw extruder, the extrusion temperature is 175-195°C, specifically divided into five heating temperature zones, the first temperature zone is 170°C ± 0.5°C, the second temperature zone is 180°C ± 0.5°C, the third temperature zone is 190°C ± 0.5°C, the fourth temperature zone is 195°C ± 0.5°C, the fifth temperature zone is 195°C ± 0.5°C, the screw speed is 38r / min, the die temperature is 192.8°C, the obtained extruded molten material is attached to the outer surface of the core wire, the traction speed is 6.4cm / s, water cooling and heat treatment: the semi-finished yarn after water cooling is placed in a 60°C oven for a stroke of 3.6m, enters an 80°C oven for a stroke of 5.4m, enters a 60°C oven for a stroke of 3.6m, and air-cooled at room temperature for a stroke of 5.4m to obtain the finished electric heating wire.
[0089] Table 2: Test parameters of the heating wire in Examples 1-10 and Comparative Example 1
[0090] Note 1: Bending resistance test method: The TH-8506 wire bending tester is used to carry out repeated bending tests on finished cables. The test is carried out in accordance with EN50396:2005+A1:2011(E). The cable transmission performance requirements refer to IEC61156-5:2020. The relevant test conditions and requirements refer to the implementation issued by the PI Association. The repeated bending radius is 7 times the outer diameter of the cable, and the hanging weight is 300g. The transmission performance is tested online when the repeated bending test reaches the set number of times. The number of bends that pass the transmission performance for the last time is the test result. When the number of bends of the sample is ≥10,000 times, it is recorded as qualified, and when the number of bends is <10,000 times, it is recorded as unqualified.
[0091] Note 2: The wiring position in the heating wire is the self-limiting temperature electric heating layer. Copper wire is used to connect the two ends of the self-limiting temperature electric heating layer on the heating wire. The resistance of the connecting copper wire is 0.1Ω. The XR-1A fiber resistivity tester of Shanghai Xinxian Instrument Co., Ltd. is used for testing.
[0092] From the comparison between Example 1 and Example 10 and the test parameters in Table 2, it can be seen that the reinforced alloy wire in the heating wire that is spirally wound around the outer wall of the self-limiting temperature electric heating layer can effectively reduce the wire resistance of the heating wire, that is, effectively improve the conductivity of the heating wire, expand the application range and application field of the heating wire, and does not affect the self-limiting temperature performance of the heating wire. It can also enhance the overall tensile strength of the heating wire and improve the mechanical properties.
[0093] By comparing Example 1 with Comparative Example 1 and the test parameters in Table 2, it can be seen that the heating wire prepared by using any one of pure copper wire, copper alloy wire, nickel-plated copper wire, aluminum alloy wire, aluminum / copper / aluminum composite wire, and copper-plated aluminum alloy wire as the core wire is compared with the heating wire prepared by using carbon fiber wire as the core wire. It can be seen that: the heating wire prepared in the present invention has smaller resistance and better conductivity, and the cost of the core wire used in the present invention is lower than that of the carbon fiber wire, that is, the heating wire provided in the present invention has a cost advantage.
[0094] Table 3: Intelligent control performance test table of the electric heating wire in Example 8
[0095] Note: The test voltage is 72.0V and the test length is 18.0m.
[0096] Power test of electric heating wire at different temperatures: resistance is the test conditions: -40℃ to 85℃, 65%RH; power supply voltage is 36-220V (select the test voltage 72V according to the needs); the test length is 18m (select the test length according to the needs, that is, the heating wire length required to simulate the electric blanket), and the copper wire is used to connect the two ends of the heating wire. The resistance of the connecting copper wire is 0.1Ω. Power test: The multi-channel power analyzer 8962A1 measuring instrument of Qingzhi Instrument is used for testing. Resistance test: The XR-1A fiber specific resistance tester of Shanghai Xinxian Instrument Co., Ltd. is used for testing. The electric heating wire is continuously powered on to test and record the changes in the resistance and power of the electric heating wire at different temperatures.
[0097] Table 4: Intelligent control performance test table of the electric heating wire in Example 9
[0098] Note: The test voltage is 12.0V and the test length is 5.0m.
[0099] Power test of electric heating wire at different temperatures: resistance is the test conditions: -40℃ to 85℃, 65%RH; power supply voltage is 36-220V (select test voltage 12V according to needs); test length is 5m (select test length according to needs, that is, simulate the heating wire length required for electric blanket), copper wire is used to connect the two ends of the heating wire, and the resistance of the connecting copper wire is 0.1Ω.
[0100] Table 5: Intelligent control performance test table of the electric heating wire in Example 7
[0101] Power test of electric heating wire at different temperatures: resistance is the test conditions: -40℃ to 85℃, 65%RH; power supply voltage is 36-220V (select test voltage 110V according to needs); test length is 5m (select test length according to needs, that is, simulate the heating wire length required for electric blanket), copper wire is used to connect the two ends of the heating wire, and the resistance of the connecting copper wire is 0.1Ω.
[0102] It can be seen from Examples 1-10 and Comparative Example 1 and Tables 2-5 that the heating wire provided in the present invention not only has a relatively low production cost but also has better safety performance compared to the existing soft copper wire and nickel-plated copper wire. At the same time, the self-limiting temperature electric heating layer emits far-infrared heating, which can act as a shielding layer, greatly weakening the electromagnetic radiation generated by the core wire, reducing the overall production cost, and meeting the lightweight design requirements.
[0103] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.
Claims
1. A heating wire, characterized in that: The heating wire comprises a core wire (1), a self-limiting temperature electric heating layer (2) coated on the outer wall of the core wire (1), and a cable insulation layer (3) coated on the outer wall of the self-limiting temperature electric heating layer (2), wherein the core wire (1) is any one of pure copper wire, copper alloy wire, nickel-plated copper wire, aluminum alloy wire, aluminum / copper / aluminum composite wire, and copper-plated aluminum alloy wire; the self-limiting temperature electric heating layer (2) is made of an electric heating material with an intelligent temperature control function; the cable insulation layer (3) is any one of a PVC insulation layer, a TPU insulation layer, and a TPEE insulation layer; the electrical conductivity ρ1 of the core wire (1) is 75-102% IACS; The resistance R1 of the core wire (1) is R1*L1 / S1, where R1 is the electrical conductivity of the core wire (1), L1 is the length of the core wire (1), and S1 is the cross-sectional area of the core wire (1); the resistance R2 of the self-limiting temperature electric heating layer (2) is R2*L2 / S2, where R2 is the electrical conductivity of the self-limiting temperature electric heating layer (2), L2 is the length of the self-limiting temperature electric heating layer (2), and S2 is the cross-sectional area of the self-limiting temperature electric heating layer (2); the resistance R1 of the heating wire can be adjusted by controlling the electrical conductivity R1 and the cross-sectional area S1 of the core wire (1). 总 and power P, and the resistance R of the heating wire can be adjusted by controlling the conductivity ρ1 and the cross-sectional area S1 of the self-limiting temperature electric heating layer (2). 总 and power P.
2. A heating wire according to claim 1, characterized in that: The electrical conductivity ρ1 of the core wire (1) is 75-90% IACS, and the core wire (1) is a high-strength and high-conductivity aluminum alloy wire with a diameter of 80-120 microns.
3. A heating wire according to claim 2, characterized in that: The mass percentages of the elements in the aluminum alloy wire are as follows: 0.40-1.2wt% of nano-aluminum clusters @ single-walled carbon nanotubes, 0.10-0.30wt% of Mg, 0.05-0.30wt% of Fe, 0.10-0.30wt% of Cu, 0.10-0.20wt% of Si, 0.05-0.20wt% of Mn, 0.05-0.20wt% of Zr, 0.004-0.012wt% of La, 0.004-0.008 of Y, 0.01-0.04wt% of Ag, the total content of unavoidable impurities is <0.10%, and the balance is Al.
4. The heating wire according to claim 1, characterized in that: The electric heating material with intelligent temperature control function is prepared from the following raw materials in percentage by mass: 10.0-40.0% of a conductive composition, 6.0-12.0% of a reinforcing agent for silk thread, 1.20-1.80% of an antioxidant composition, 0.20-0.40% of an anti-ultraviolet agent, 0.10-0.30% of a dispersant, and the remainder being a base resin; the base resin is composed of PP resin, HDPE resin, and EVA resin; the conductivity ρ2 of the self-limiting temperature electric heating layer (2) prepared from the electric heating material with intelligent temperature control function is 44.27-2.27*10 4 Ω*mm 2 / m, the cross-sectional area S2 of the self-limiting temperature electric heating layer (2) is 0.8-3.2 mm 2 .
5. A heating wire according to claim 4, characterized in that: The matrix resin is composed of PP resin, EVA resin and HDPE resin in a mass ratio of (78-82):(18-22):(36-44).
6. A heating wire according to claim 5, characterized in that: The conductive composition is composed of the following raw materials in percentage by weight: 5.0-20wt% of nano titanium diboride, 1.0-10wt% of multi-walled carbon nanotubes, 1.0-10wt% of highly conductive graphene, 0.5-5wt% of titanium nitride whiskers, and the balance is nano carbon black; the nano titanium diboride has an average particle size of 0.05-30μm and a hexagonal crystal form; the multi-walled carbon nanotube has a diameter of 5-50μm, a purity of >95w%, and a SSA of >110m 2 / g, ash content <5.0wt%; the number of layers of the highly conductive graphene is <5, purity >99w%, sheet diameter 0.2-0.5μm, SSA>300m 2 / g, ash content <1wt%.
7. A heating wire according to claim 6, characterized in that: The reinforcing auxiliary agent for silk thread is composed of nano zinc oxide, nano zirconium oxide, nano silicon nitride and boron nitride nano sheets in a mass ratio of (55-90):(5-20):(5-20):(0.5-5).
8. The heating wire according to claim 1, characterized in that: It also includes a reinforced alloy wire (4) spirally wound around the outer wall of the self-limiting temperature electric heating layer (2), wherein the reinforced alloy wire (4) is located between the self-limiting temperature electric heating layer (2) and the cable insulation layer (3); The resistance R3 of the reinforced alloy wire (4) is R3=ρ3*L3 / S3, where ρ3 is the electrical conductivity of the reinforced alloy wire (4), L3 is the length of the reinforced alloy wire (4), and S3 is the cross-sectional area of the reinforced alloy wire (4); The pitch of the reinforcing alloy wire (4) is D, and the length of the reinforcing alloy wire (4) is L3 2 =D 2 +S4 2 , S4 is the circumference of the self-limiting temperature electric heating layer (2), that is, S4=2πr, r is the outer diameter of the self-limiting temperature electric heating layer (2); The resistance R of the heating wire can be adjusted by controlling the conductivity ρ1 and the cross-sectional area S1 of the core wire (1). 总 and power P, and the resistance R of the heating wire can be adjusted by controlling the conductivity ρ1 and the cross-sectional area S1 of the self-limiting temperature electric heating layer (2). 总 and power P. In addition, the resistance R of the heating wire can be adjusted by controlling the conductivity ρ3 and cross-sectional area S3 of the enhanced alloy wire (4). 总 and power P.
9. A method for preparing a heating wire according to any one of claims 1 to 8, characterized in that: The method comprises the following steps: step 1, preparing an electric heating material with an intelligent temperature control function; step 2, placing a spinning masterbatch in a twin-screw extruder for melt extrusion, attaching the obtained extruded molten material to the outer surface of a core wire (1), water cooling, heat treatment, and drying to obtain a semi-finished heating wire; step 3, placing a polymer insulating resin in a twin-screw extruder for melt extrusion, attaching the obtained extruded molten material to the outer surface of the semi-finished heating wire, water cooling, heat treatment, drying, and winding to obtain a finished heating wire.
10. The method for preparing a heating wire according to claim 9, characterized in that: The method comprises the following steps: step 1, preparing an electric heating material with an intelligent temperature control function; step 2, placing a spinning masterbatch in a twin-screw extruder for melt extrusion, attaching the obtained extruded molten material to the outer surface of a core wire (1), water cooling, heat treatment, and drying to obtain a semi-finished heating wire; step 3, spirally winding a reinforcing alloy wire (4) around the outer wall of the semi-finished heating wire to obtain a primary heating wire; step 4, placing a polymer insulating resin in a twin-screw extruder for melt extrusion, attaching the obtained extruded molten material to the outer surface of the primary heating wire, water cooling, heat treatment, drying, and winding to obtain a finished heating wire.