A method for manufacturing high temperature resistant and puncture resistant enameled square wire

Abstract

The present invention discloses a method for making a high temperature resistant and puncture resistant enameled square wire, which comprises the following steps: laying off wire; drawing wire to obtain round wire; rolling to preliminarily shape the round wire into a flat wire with a semicircular cross-sectional R angle; first shaping to obtain a flat wire with an octagonal cross-sectional area; second shaping to obtain a square wire with a cross-sectional R angle radius of 0.015±0.005mm; cleaning; annealing; first painting, first baking, first cooling; second painting, second baking and second cooling to obtain an enameled square wire; wherein the paint for the first painting is PAI, and the paint for the second painting is PI; the ratio of PI to PAI is 1:9. The present invention can make the product have good high temperature resistance and puncture resistance, and the cost is low; in the mold shaping process, the stress of each part of the conductor is uniform, the processing amount of the conductor cross-sectional R angle is increased, and the uniformity of subsequent paint film coating is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of enameled wire production, and in particular relates to a method for manufacturing a high-temperature resistant and puncture resistant enameled square wire. Background Art

[0002] The existing enameled square wire is composed of paint film and square conductor, and is widely used in various inductors, electrical appliances, motors, voice coils, car multimedia and other products. In particular, in recent years, 5G mobile phones, 5G equipment, artificial intelligence machines, new energy and intelligent electrical appliances and automobiles have grown rapidly and demand has increased. These high-end products have extremely high added value, which brings a broader application field and bright prospects for the enameled wire. However, the high temperature resistance and puncture resistance of existing enameled square wire products are still poor.

[0003] In addition, in the production process of enameled square wire, the conductor is first drawn into a round wire by a wire drawing device, and then the round wire is pressed into a flat wire by a calendering process, and then the flat wire is shaped into a square wire by a mold. However, in the existing production process of enameled square wire, in order to improve production efficiency, usually only one mold shaping process is performed, that is, the conductor is shaped into a square shape by hard drawing, resulting in uneven force on various parts of the conductor, which is prone to wire breakage in the subsequent production process, and the overall performance is poor; at the same time, because the conductor is only subjected to one mold shaping process, the processing amount of the conductor cross-section R angle is not reasonable and sufficient, making the conductor cross-section R angle not smooth enough, which is not conducive to the uniformity of subsequent paint film coating. Summary of the invention

[0004] The purpose of the present invention is to provide a low-cost method for producing high-temperature resistant and puncture-resistant enameled square wire. During the mold shaping process, the stress on each part of the conductor is uniform, the processing amount of the R angle of the conductor cross section is increased, and the uniformity of subsequent paint film coating is improved.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] A method for manufacturing high temperature resistant and puncture resistant enameled square wire, comprising the following steps:

[0007] Step S1: Leading the conductor out of the wire-paying device and drawing it into a round wire through a wire drawing device;

[0008] Step S2: rolling the round wire to preliminarily shape the round wire into a flat wire with a semicircular cross-sectional R angle;

[0009] Step S3: using a first mold to perform a first shaping process on the flat wire obtained after the process in step S2, to obtain a flat wire with a cross section of a substantially octagonal shape;

[0010] Step S4: using a second die to perform a second shaping process on the flat wire obtained after the process in step S3, to obtain a square wire with a cross-sectional R angle radius of 0.015±0.005mm; the cross-sectional area of ​​the wire passage in the second die is 5%±3% smaller than the cross-sectional area of ​​the wire passage in the first die;

[0011] Step S5: cleaning the square wire;

[0012] Step S6: performing annealing treatment on the square wire after the cleaning treatment;

[0013] Step S7: performing a first painting process, a first baking process and a first cooling process on the square wire after the annealing process in sequence; wherein the paint for the first painting process is PAI;

[0014] Step S8: performing a second painting treatment, a second baking treatment and a second cooling treatment on the square wire after the treatment in step S7 in sequence to obtain an enameled square wire; wherein the paint for the second painting treatment is PI; and the ratio of the paint for the second painting treatment to the paint for the first painting treatment is 1:9.

[0015] As a preferred solution of the present invention, arc transitions are provided at the tangent points of the straight edge of the first mold and the R-angle arc line and at the tangent points of the straight edge of the second mold and the R-angle arc line.

[0016] As a preferred embodiment of the present invention, step S9 is also included. When the enameled square wire needs to be coated with a self-adhesive paint layer, the enameled square wire is sequentially subjected to a third painting treatment, a third baking treatment, a third cooling treatment, a lubrication treatment and a wire winding treatment to obtain a finished enameled square wire.

[0017] As a preferred embodiment of the present invention, step S9 is further included, in which when the enameled square wire does not need to be coated with a self-adhesive paint layer, the enameled square wire is lubricated and wound up in sequence to obtain a finished enameled square wire.

[0018] As a preferred embodiment of the present invention, the paint in the third painting process is one of HB, SB or SV.

[0019] As a preferred embodiment of the present invention, in step S7, the first painting treatment is performed by applying one or more coats of paint to the square wire using a high-pressure sealed spray so that the thickness of the single-side paint film is 0.3 μm to 6 μm.

[0020] As a preferred embodiment of the present invention, in step S8, the second painting treatment is performed by applying one or more coats of paint to the square wire using a high-pressure sealed spray so that the thickness of the single-side paint film is 0.3 μm to 6 μm.

[0021] As a preferred embodiment of the present invention, in step S1, the conductor is one of copper, silver, aluminum, aluminum alloy, copper-clad aluminum and tinned copper.

[0022] As a preferred embodiment of the present invention, the annealing temperature of the square wire in step S6 is: copper: 400-550°C; silver: 500-650°C; aluminum: 350-450°C; aluminum alloy: 400-500°C; aluminum-clad copper: 300-400°C; tin-plated copper: 600-700°C.

[0023] The method for manufacturing a high temperature resistant and puncture resistant enameled square wire provided by the present invention has the following beneficial effects compared with the prior art:

[0024] 1. After the conductor is drawn into a round wire by the wire drawing equipment, it is subjected to calendering treatment, the first shaping treatment and the second shaping treatment in sequence, and the conductor is gradually shaped into a flat wire with a semicircular cross-sectional R angle, a flat wire with an octagonal cross-sectional area and a square wire with a cross-sectional R angle radius of 0.015±0.005mm. Thus, by gradually shaping the conductor, compared with the prior art method of shaping the conductor into a square shape by hard drawing, the stress on each part of the conductor can be uniform, and the wire is not easy to break in the subsequent production process; at the same time, the processing amount of the conductor cross-sectional R angle can be reasonably and fully increased, so that the conductor cross-sectional R angle is smoother, which is more conducive to the uniformity of subsequent paint film coating.

[0025] 2. After annealing, the square wire was painted twice. The paint for the first painting was PAI, which gave the product better puncture resistance; the paint for the second painting was PI, which gave the product better high temperature resistance. Since PI-based materials are expensive, coating uniformity is difficult, storage conditions are harsh and the shelf life is short, PAI and PI are combined in this embodiment. After processing, the insulation layer of the finished wire is a combination of PAI and PI, and the ratio of PI to PAI is 1:9. The cost of this product is lower than that of simply coating PI insulation material, and the heat resistance is higher than that of coating PAI insulation material alone. The softening breakdown test by the temperature rise method is at least 100°C higher, and it can withstand higher temperature and high pressure harsh operating conditions. DETAILED DESCRIPTION

[0026] The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0027] In the description of the present invention, it should be understood that the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", etc. indicate positions or positional relationships based on the shown positions or positional relationships, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. It should be understood that the terms "first", "second", etc. are used in the present invention to describe various information, but such information should not be limited to these terms, which are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present invention, "first" information may also be referred to as "second" information, and similarly, "second" information may also be referred to as "first" information.

[0028] A preferred embodiment of the present invention provides a method for manufacturing a high temperature resistant and puncture resistant enameled square wire, which comprises the following steps:

[0029] Step S1: Lead the conductor out of the wire-laying device and draw it into a round wire through a wire-drawing device. It should be noted that the conductor used in this step is one of copper, silver, aluminum, aluminum alloy, copper-clad aluminum and tinned copper.

[0030] Step S2: rolling the round wire to preliminarily shape the round wire into a flat wire with a semicircular R angle. It should be noted that in this step, using at least two rollers to roll the round wire multiple times can make the force more uniform and prevent the wire from breaking.

[0031] Step S3: Use the first mold to perform the first shaping process on the flat wire obtained after the step S2 to obtain a flat wire with an octagonal cross section. It should be noted that in this step, using the first mold to shape the wire into a flat wire with an octagonal cross section is a better choice. If the deformation of the flat wire is small (such as shaping into a flat wire with a decagonal cross section), it is close to a round wire, which is not conducive to subsequent processing; if the deformation of the flat wire is large (such as shaping into a flat wire with a hexagonal cross section), it is easy to damage the flat wire and cause wire breakage.

[0032] Step S4: Use a second die to perform a second shaping process on the flat wire obtained after the process in step S3, and obtain a square wire with an R corner radius of 0.015±0.005mm; the cross-sectional area of ​​the wire passage in the second die is 5%±3% smaller than the cross-sectional area of ​​the wire passage in the first die. It should be noted that in this step, it is a better choice that the cross-sectional area of ​​the wire passage in the second die is 5%±3% smaller than the cross-sectional area of ​​the wire passage in the first die. If it is greater than 5%±3%, it will lead to insufficient processing and it will be difficult to obtain a wire with a square cross-section; if it is less than 5%±3%, it is easy to damage the flat wire and affect the service life of the die.

[0033] Step S5: Clean the square wire to clean the oil and powder on the conductor surface. Generally, ultrasonic cleaning can make the conductor surface smoother and the product more adherent, which is convenient for the subsequent painting step.

[0034] Step S6: Annealing the square wire after cleaning can eliminate the structural defects and internal stress caused to the wire in the previous steps, making the R angle of the conductor smoother and flatter. It should be noted that in this step, the annealing temperature corresponding to each conductor is: copper: 400-550°C; silver: 500-650°C; aluminum: 350-450°C; aluminum alloy: 400-500°C; aluminum-clad copper: 300-400°C; tinned copper: 600-700°C.

[0035] Step S7: The square wire after annealing is subjected to a first painting treatment, a first baking treatment and a first cooling treatment in sequence; wherein the paint of the first painting treatment is PAI. It should be noted that the first painting treatment is carried out by using a high-pressure sealed spray to coat the square wire once or multiple times, so that the thickness of the single-side paint film is 0.3 μm to 6 μm.

[0036] Step S8: The square wire after the step S7 is subjected to a second painting treatment, a second baking treatment and a second cooling treatment in sequence to obtain an enameled square wire. The paint for the second painting treatment is PI; the ratio of the paint for the second painting treatment to the paint for the first painting treatment is 1:9. It should be noted that the second painting treatment is preferably carried out by using a high-pressure sealed spray to coat the square wire once or multiple times, so that the thickness of the single-side paint film is 0.3μm to 6μm.

[0037] According to the method for making high temperature resistant and puncture resistant enameled square wire of the present invention, after the conductor is drawn into a round wire by the wire drawing equipment, it is successively subjected to calendering treatment, first shaping treatment and second shaping treatment, and the conductor is gradually shaped into a flat wire with a semicircular R angle, a flat wire with an octagonal cross section and a square wire with a cross section R angle radius of 0.015±0.005mm. Thus, by gradually shaping the conductor, compared with the method of shaping the conductor into a square shape by hard drawing in the prior art, the stress on each part of the conductor can be uniform, and it is not easy to break the wire in the subsequent production process; at the same time, it can also reasonably and fully increase the processing amount of the conductor cross section R angle, so that the conductor cross section R angle is smoother, which is more conducive to the uniformity of the subsequent paint film coating. In addition, after the annealing treatment, the square wire was painted twice, the paint for the first painting treatment was PAI, so that the product has better puncture resistance; the paint for the second painting treatment was PI, so that the product has better high temperature resistance. Since PI-based materials are expensive, coating uniformity is difficult, storage conditions are harsh and the shelf life is short, PAI and PI are combined in this embodiment. After processing, the insulation layer of the finished wire is a combination of PAI and PI, and the ratio of PI to PAI is 1:9. This product has lower costs than simply coating PI insulation material and higher heat resistance than simply coating PAI insulation material. The softening breakdown test by the temperature rise method is at least 100°C higher, and it can withstand higher temperature and high pressure harsh operating conditions.

[0038] Exemplarily, arc transitions are provided at the tangent points of the straight edge of the first mold and the R-angle arc line and at the tangent points of the straight edge of the second mold and the R-angle arc line, so that the cross-sectional R angle of the conductor can be smoother, which is beneficial to uniform coating of the paint film and improves the overall performance of the product.

[0039] Exemplarily, this embodiment also includes step S9, when the enameled square wire needs to be coated with a self-adhesive paint layer, the enameled square wire is sequentially subjected to a third painting treatment, a third baking treatment, a third cooling treatment, a lubrication treatment and a wire winding treatment to obtain a finished enameled square wire, wherein the paint in the third painting treatment is preferably one of HB, SB or SV; when the enameled square wire does not need to be coated with a self-adhesive paint layer, the enameled square wire is sequentially subjected to a lubrication treatment and a wire winding treatment to obtain a finished enameled square wire.

[0040] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A method for producing high temperature resistant and puncture resistant enameled square wire, characterized in that: The steps include: Step S1: Leading the conductor out of the wire-paying device and drawing it into a round wire through a wire drawing device; Step S2: rolling the round wire to preliminarily shape the round wire into a flat wire with a semicircular cross-sectional R angle; Step S3: using a first mold to perform a first shaping process on the flat wire obtained after the process in step S2, to obtain a flat wire with a cross section of a substantially octagonal shape; Step S4: using a second die to perform a second shaping process on the flat wire obtained after the process in step S3, to obtain a square wire with a cross-sectional R angle radius of 0.015±0.005mm; the cross-sectional area of ​​the wire passage in the second die is 5%±3% smaller than the cross-sectional area of ​​the wire passage in the first die; Step S5: cleaning the square wire; Step S6: performing annealing treatment on the square wire after the cleaning treatment; Step S7: sequentially performing a first painting treatment, a first baking treatment and a first cooling treatment on the square wire after the annealing treatment; wherein the paint of the first painting treatment is PAI; the first painting treatment is performed by: using a high-pressure sealed spray to perform one or more multi-pass coating on the square wire, so that the thickness of the single-side paint film is 0.3μm to 6μm; Step S8: The square wire after the treatment in step S7 is subjected to a second painting treatment, a second baking treatment and a second cooling treatment in sequence to obtain an enameled square wire; wherein the paint for the second painting treatment is PI; the ratio of the paint for the second painting treatment to the paint for the first painting treatment is 1:9; the second painting treatment is carried out by using a high-pressure sealed spray to apply one or more coats of the square wire so that the thickness of the single-side paint film is 0.3μm to 6μm.

2. The method for producing high temperature resistant and puncture resistant enameled square wire according to claim 1, characterized in that: Arc transitions are provided at the tangent points between the straight edge of the first mold and the R-angle arc line and at the tangent points between the straight edge of the second mold and the R-angle arc line.

3. The method for producing high temperature resistant and puncture resistant enameled square wire according to claim 2, characterized in that: The method further includes step S9, in which, when the enameled square wire needs to be coated with a self-adhesive paint layer, the enameled square wire is sequentially subjected to a third painting treatment, a third baking treatment, a third cooling treatment, a lubrication treatment and a wire winding treatment to obtain a finished enameled square wire.

4. The method for producing high temperature resistant and puncture resistant enameled square wire according to claim 2, characterized in that: The method further includes step S9, when the enameled square wire does not need to be coated with a self-adhesive paint layer, lubricating and winding the enameled square wire in sequence to obtain a finished enameled square wire.

5. The method for producing high temperature resistant and puncture resistant enameled square wire according to claim 3, characterized in that: The paint in the third painting process is one of HB, SB or SV.

6. The method for producing high temperature resistant and puncture resistant enameled square wire according to claim 1, characterized in that: In the step S1, the conductor is one of copper, silver, aluminum, aluminum alloy, copper-clad aluminum and tinned copper.

7. The method for producing high temperature resistant and puncture resistant enameled square wire according to claim 1, characterized in that: The annealing temperature of the square wire in step S6 is: copper: 400-550°C; Silver: 500-650°C; Aluminum: 350-450°C; Aluminum alloy: 400~500℃; aluminum clad copper: 300~400℃; tinned copper: 600~700℃.