Hydrolysis chemical reaction paint removing method for enameled copper wire with extremely small wire diameter and fixed length

Abstract

The invention relates to a hydrolytic chemical reaction depainting method for an enameled copper wire with an extremely small wire diameter and a fixed length, which comprises the following steps: preparing a latent solvent, and injecting the latent solvent into a depainting tank of a latent dissolving instrument; the product is loaded on a limiting tool, it is guaranteed that the depainting section of the product can be immersed in the latent solvent, and the non-depainting section of the product cannot be immersed in the latent solvent; starting a latent dissolving instrument to remove paint; after the paint removal reaction is finished, the product loaded on the limiting tool is taken down; and cleaning and drying the taken-down product. The problems of low mechanical polishing efficiency and high loss rate at present are solved, meanwhile, the hydrolytic chemical reaction is fast, the process is green and environmentally friendly, and adverse effects on the environment and occupational health cannot be caused; the paint removing length is guaranteed by the tool, the difference caused by personnel operation is reduced, and the quality consistency is improved.

Description

Technical Field

[0001] This invention belongs to the field of pyrotechnics design technology and relates to a method for removing the enamel coating from enameled copper wire with an extremely fine diameter (less than 1 mm) and a fixed length through a hydrolytic chemical reaction. Background Technology

[0002] In aerospace pyrotechnics manufacturing, QY-3 / 220 grade (indicating three layers of polyimide film plated onto the surface of copper conductors at 220℃) polyimide enameled copper wire is frequently used as a key electrical component in electric detonating tubes due to its excellent comprehensive properties, including high strength, light weight, good electrical performance, and good structural stability. In the production process of electric detonating tubes, the process of removing the enamel coating and tinning the enameled copper wire for the plug assembly is crucial for ensuring the subsequent soldering and electrical performance of the product; therefore, strict requirements are placed on the length and quality of the enamel removal and tinning process.

[0003] Currently, there are two main methods for removing the insulating varnish layer from the surface of enameled copper wire:

[0004] One method is to mechanically grind and scrape the enamel coating directly with a sharp blade. However, this method can only grind one enameled copper wire at a time, resulting in low enamel removal efficiency. When the wire diameter is less than 1mm and a fixed length of enamel layer needs to be removed, the physical grinding directly applies stress to the surface of the thin wire, making it very easy to break or scratch the wire during the grinding process, resulting in a high loss rate.

[0005] Another method involves preparing a paint remover, immersing the enameled copper wire in the remover to react and remove the enamel film from the copper wire. Currently, the commonly used paint remover is prepared by dichloromethane:formic acid = (70±2)%: (30±2)%. This type of paint remover is effective for removing the enamel from polyester enameled copper wire, but it is very difficult to remove the enamel from high-temperature 220 grade polyimide enameled copper wire, and the reaction effect is not ideal.

[0006] Furthermore, Article 38 of the "Prohibited Processes for Aerospace Model Products" list prohibits the use of steel brushes, scrapers, and other tools that are prone to generating sparks when removing old paint with organic solvents or solvent-based paint removers. The reason for the prohibition is that it may cause fire or explosion accidents. The recommended alternative process is to use tools made of aluminum, copper, or non-metallic materials.

[0007] Therefore, there is an urgent need to find a low-loss, high-efficiency method for removing the enamel layer from ultra-fine diameter (less than 1 mm) fixed-length polyimide enameled copper wires. Summary of the Invention

[0008] The technical problem solved by this invention is to overcome the shortcomings of the prior art and propose a hydrolytic chemical reaction method for removing enamel from enameled copper wire with an ultra-fine wire diameter (less than 1 mm) and a fixed length. This method solves the problems of low efficiency and high loss rate of current mechanical polishing. At the same time, the hydrolytic chemical reaction is fast, the process is green and environmentally friendly, and will not have adverse effects on the environment or occupational health.

[0009] The technical problem further solved by this invention is that the paint removal length is guaranteed by the tooling, which reduces the differences caused by human operation and is conducive to improving the consistency of quality.

[0010] The solution of the present invention is:

[0011] A method for removing the enamel coating from ultra-fine diameter, fixed-length enameled copper wire via hydrolysis chemical reaction, comprising:

[0012] The preparation process of the co-solvent is as follows: According to the required amount of co-solvent, measure 2,2′-dihydroxydiethylamine, ammonia-based organic compounds, alkane-ketone derivatives, surfactants, and copper corrosion inhibitors sequentially using a graduated cylinder; pour 2,2′-dihydroxydiethylamine into a beaker, and then add ammonia-based organic compounds, alkane-ketone derivatives, surfactants, and copper corrosion inhibitors sequentially, stirring slowly with a glass rod continuously during the addition process to ensure that all components are mixed evenly; after thorough stirring and uniform mixing of all components, pour the co-solvent into a plastic container, cover, and store.

[0013] Inject the latent solvent into the paint stripping tank of the latent solvent extractor;

[0014] The product is loaded onto a limiting fixture, which ensures that the paint stripping section of the product can be immersed in the latent solvent, while the non-paint stripping section is not immersed in the latent solvent.

[0015] Start the solvent remover to remove the paint;

[0016] After the paint stripping reaction is complete, remove the product loaded onto the limiting fixture;

[0017] The removed products are then cleaned and dried.

[0018] Preferably, the conditions for storing the latent solvent in a plastic bucket with a lid are: storing it in an environment with a relative temperature of (15-35)℃ and a relative humidity of no more than 65%, avoiding direct sunlight, and the shelf life is 180 days.

[0019] Preferably, the latent solvent is injected into the paint stripping tank of the latent solvent apparatus, and the steps are as follows:

[0020] (1) Click the power button on the dissolving agent;

[0021] (2) Insert the inlet hose of the liquid extractor into the plastic bucket containing the liquid extractor, click the "Add Liquid" button, and the liquid extractor will automatically draw the liquid extractor into the paint stripping tank. When the calibrated liquid level is reached, the drawing will automatically stop.

[0022] (3) Insert the liquid outlet hose of the liquid dissolving device into the plastic bucket for collecting waste liquid.

[0023] Preferably, before loading the product onto the limiting fixture, the enameled copper wires of the product should be straightened to prevent them from overlapping.

[0024] Preferably, the paint is removed by starting the solvent remover, and the steps are as follows:

[0025] (1) Set the paint removal time of the latent solvent remover and click the "automatic replenishment" button of the latent solvent remover;

[0026] (2) Click the "Exhaust" button on the paint stripper to promptly extract and exhaust the gas from the product during the paint stripping process;

[0027] (3) Click the “Start Paint Removal” button on the paint remover to remove the paint.

[0028] Preferably, if the level of the latent solvent falls below the initial level during the paint stripping process, the latent solvent apparatus will automatically replenish the solvent to maintain a constant liquid level.

[0029] Preferably, if the paint removal effect is poor and the paint layer is not completely removed, the solution needs to be changed. When changing the solution, click the "drain" button of the submersible solvent instrument to discharge the waste liquid into the waste liquid bucket for collection. Then, insert the liquid inlet hose of the submersible solvent instrument into the plastic bucket containing the submersible solvent and click the "add liquid" button. The submersible solvent instrument will draw the submersible solvent into the paint removal tank. When the calibrated liquid level is reached, the drawing will automatically stop.

[0030] Preferably, the removed products are cleaned and dried, as follows:

[0031] Soak the removed product in anhydrous ethanol solution for more than 20 minutes, then clean the enameled copper wire with a brush, air dry it, and then put it in a constant temperature water bath oven at (60±2)℃ to dry for 2 hours.

[0032] Preferably, the ultra-fine wire diameter refers to a diameter of less than 1 mm.

[0033] Preferably, the limiting fixture can load multiple products simultaneously, enabling simultaneous paint removal from multiple products.

[0034] The advantages of this invention compared to the prior art are:

[0035] (1) Compared to mechanical physical grinding and scraping, the method of this invention achieves the goal of removing paint from multiple wires simultaneously. For wires with a diameter (less than 1mm) and requiring the removal of a fixed length of paint layer, this method achieves the goal of paint removal without loss and with a fixed length. Mechanical physical grinding and scraping cannot effectively control the grinding dimensions, and the grinding quality varies for different operators, affecting the subsequent tinning quality of the copper wires. The main process of paint removal using a latent solvent is guaranteed by tooling, reducing the differences caused by human operation, which is conducive to improving the consistency of quality, greatly reducing the product loss rate, and effectively improving grinding efficiency.

[0036] (2) Compared with dichloromethane-formic acid paint remover, the method of the present invention can not only remove paint from polyester enameled copper wire, but also from polyimide enameled copper wire, which has a wider range of applications. Moreover, the paint removal process is safe and green, with no irritating odor release, which is beneficial to protecting occupational health.

[0037] (3) The principle of the present invention for removing paint with a latent solvent is to decompose the paint film in contact with the latent solvent. Therefore, the paint film interface is neater, cleaner and clearer than that of mechanical sanding.

[0038] (4) The latent solvent of the present invention can effectively remove polyimide paint film without damaging or corroding the non-painted section and the exposed copper core wire after paint removal, and the appearance after paint removal meets the requirements. Attached Figure Description

[0039] Figure 1 This is a process flow diagram of a hydrolytic chemical reaction method for removing enamel from enameled copper wire of extremely fine diameter (less than 1 mm) and fixed length, according to the present invention. Detailed Implementation

[0040] The present invention will be further described below with reference to the embodiments.

[0041] like Figure 1 As shown, the present invention discloses a method for removing enamel coating from ultra-fine diameter (less than 1 mm) and fixed-length enameled copper wire via hydrolysis chemical reaction. The method mainly includes preparing a latent solvent, injecting the latent solvent into the latent solvent bath, loading the product into the tooling, starting the latent solvent bath for enamel removal, removing the product, and cleaning and drying the product. In the latent solvent preparation step, a latent solvent formulation is used with ammonia-based organic compounds and alkane derivatives as solvents, and 2,2′-dihydroxydiethylamine as the solute. The components and their proportions are as follows: 2,2′-dihydroxydiethylamine (20%–35%), ammonia-based organic compounds (5%–10%), alkane derivatives (35%–50%), surfactant (5%–20%), and copper corrosion inhibitor (0.3%–1%).

[0042] The implementation steps of this invention are as follows:

[0043] 1. Preparation of co-solvent:

[0044] (1) According to the required amount of the latent solvent, measure 2,2′-dihydroxydiethylamine, ammonia organic compounds, alkane-ketone derivatives, surfactants and copper corrosion inhibitors in sequence using a graduated cylinder;

[0045] The composition of the copper corrosion inhibitor is as follows: 2,2′-dihydroxydiethylamine has a mass percentage of 20%–35%, ammonia-based organic compounds have a mass percentage of 5%–10%, alkane-ketone derivatives have a mass percentage of 35%–50%, surfactants have a mass percentage of 5%–20%, and copper corrosion inhibitors have a mass percentage of 0.3%–1%.

[0046] (2) Pour 2,2′-dihydroxydiethylamine into a beaker, and then add ammonia organic compounds, alkane derivatives, surfactants and copper corrosion inhibitors in sequence. Stir slowly with a glass rod throughout the addition process to ensure that the components are mixed evenly.

[0047] (3) Stir thoroughly for more than 15 minutes. After the components are mixed evenly, pour the latent solvent into a plastic bucket, cover it, and temporarily store it in an environment with a relative temperature of (15-35)℃ and a relative humidity of no more than 65%. Avoid direct sunlight. The shelf life is 180 days.

[0048] 2. Injecting the latent solvent into the paint stripping tank of the latent solvent apparatus:

[0049] (1) Click the power button on the dissolving agent;

[0050] (2) Insert the inlet hose of the liquid dissolving device into the plastic bucket containing the liquid dissolving agent, click the "Add Liquid" button, and the liquid dissolving device will automatically draw the liquid dissolving agent into the paint stripping tank. When the liquid level reaches the calibration level (the height of the liquid level from the opening of the paint stripping tank is 9mm), the pumping will automatically stop.

[0051] (3) Insert the liquid outlet hose of the liquid dissolving device into the plastic bucket for collecting waste liquid.

[0052] 3. Tooling for loading products:

[0053] (1) Before loading, straighten the enameled copper wires to avoid overlapping.

[0054] (2) Select a suitable limiting fixture. For example, the product requires a (14±0.5)mm unremoved paint section. It is known that the height from the surface of the latent solvent to the opening of the paint stripping tank of the latent solvent instrument is 9mm. Therefore, a limiting fixture with a height of 5mm is suitable.

[0055] (3) Load the product into the limiting fixture to ensure that the paint stripping section can be immersed in the latent solvent, while the non-paint stripping section is not immersed in the latent solvent.

[0056] 4. Start the solvent remover to remove the paint:

[0057] (1) Set the paint removal time of the latent solvent apparatus to 120s and click the "automatic replenishment" button of the latent solvent apparatus;

[0058] (2) Click the "Exhaust" button on the paint stripper to promptly extract and exhaust the gas from the product during the paint stripping process;

[0059] (3) Click the “Start Removing Paint” button of the latent solvent remover. The latent solvent remover uses a series resonant circuit inside. The inverter principle makes the AC power supply generate an alternating magnetic field, which ionizes the latent solvent molecules. At the same time, it uses the principle of magnetothermal reaction of metal in magnetic field to cause the polymer chain of organic paint film of enameled wire to break and dissolve, so as to remove the insulating paint.

[0060] (4) If the liquid level falls below the initial level during the paint stripping process, the liquid level absorber will automatically replenish the liquid to maintain the liquid level height.

[0061] (5) If the paint removal effect is poor and the paint layer is not completely removed, the liquid needs to be changed. Click the "drain" button of the liquid remover to discharge the waste liquid into the waste liquid bucket. Repeat step (2) in step 2 and inject new liquid remover to remove the paint.

[0062] 5. Remove the product: After the 120s paint stripping reaction is complete, remove the product loaded on the limiting fixture.

[0063] 6. Product cleaning and drying:

[0064] Soak the product in anhydrous ethanol solution for more than 20 minutes, then clean the enameled copper wire with a brush, air dry for 30 minutes, and then put it into a constant temperature water bath oven at (60±2)℃ to dry for 2 hours.

[0065] This invention provides a hydrolytic chemical reaction method for removing enamel from ultra-fine diameter (less than 1 mm) enameled copper wires of fixed length. This method enables simultaneous enamel removal from multiple wires. Specifically designed for wires with a diameter less than 1 mm requiring the removal of a fixed length of enamel layer, this method achieves lossless, fixed-length enamel removal. Mechanical physical grinding and scraping cannot effectively control the grinding dimensions, and the grinding quality varies depending on the operator, affecting the subsequent tinning quality of the copper wires. Using a latent solvent for enamel removal reduces variations caused by operator error, improves quality consistency, significantly reduces product loss, and effectively increases grinding efficiency.

[0066] The undisclosed technologies in this invention are common knowledge to those skilled in the art.

Claims

1. A method for removing the enamel coating from enameled copper wire of extremely fine diameter and fixed length via hydrolysis chemical reaction, characterized in that, include: The preparation process of the co-solvent is as follows: According to the required amount of co-solvent, measure 2,2′-dihydroxydiethylamine, ammonia-based organic compounds, alkane-ketone derivatives, surfactants, and copper corrosion inhibitors sequentially using a graduated cylinder; pour 2,2′-dihydroxydiethylamine into a beaker, and then add ammonia-based organic compounds, alkane-ketone derivatives, surfactants, and copper corrosion inhibitors sequentially, stirring slowly with a glass rod continuously during the addition process to ensure that all components are mixed evenly; after thorough stirring and uniform mixing of all components, pour the co-solvent into a plastic container, cover, and store. Inject the latent solvent into the paint stripping tank of the latent solvent extractor; The product is loaded onto a limiting fixture, which ensures that the paint stripping section of the product can be immersed in the latent solvent, while the non-paint stripping section is not immersed in the latent solvent. Start the solvent remover to remove the paint; After the paint stripping reaction is complete, remove the product loaded onto the limiting fixture; The removed products are then cleaned and dried.

2. The method for removing the enamel coating from ultra-fine diameter, fixed-length enameled copper wire via hydrolysis chemical reaction according to claim 1, characterized in that, The conditions for storing the latent solvent in a plastic container with a lid are: store it in an environment with a relative temperature of (15-35)℃ and a relative humidity of no more than 65%, avoid direct sunlight, and the shelf life is 180 days.

3. The method for removing the enamel coating from ultra-fine diameter, fixed-length enameled copper wire via hydrolysis chemical reaction according to claim 1, characterized in that, The following steps are taken to inject the latent solvent into the paint stripping tank of the latent solvent apparatus: (1) Click the power button on the dissolving agent; (2) Insert the inlet hose of the liquid extractor into the plastic bucket containing the liquid extractor, click the "Add Liquid" button, and the liquid extractor will automatically draw the liquid extractor into the paint stripping tank. When the calibrated liquid level is reached, the drawing will automatically stop. (3) Insert the liquid outlet hose of the liquid dissolving device into the plastic bucket for collecting waste liquid.

4. The method for removing the enamel coating from ultra-fine diameter, fixed-length enameled copper wire via hydrolysis chemical reaction according to claim 1, characterized in that, Before loading the product onto the limiting fixture, straighten the enameled copper wires of the product to prevent them from overlapping.

5. The method for removing the enamel coating from ultra-fine diameter, fixed-length enameled copper wire via hydrolysis chemical reaction according to claim 1, characterized in that, To use the paint remover, follow these steps: (1) Set the paint removal time of the latent solvent extractor and click the "automatic liquid replenishment" button of the latent solvent extractor; (2) Click the "Exhaust" button on the paint stripper to promptly extract and exhaust the gas from the product during the paint stripping process; (3) Click the "Start Paint Removal" button on the paint remover to remove the paint.

6. The method for removing the enamel coating from ultra-fine diameter, fixed-length enameled copper wire via hydrolysis chemical reaction according to claim 5, characterized in that, If the level of the latent solvent falls below the initial level during the paint stripping process, the latent solvent apparatus will automatically replenish the solvent to maintain a constant liquid level.

7. The method for removing the enamel coating from ultra-fine diameter, fixed-length enameled copper wire via hydrolysis chemical reaction according to claim 5, characterized in that, If the paint stripping effect is poor and the paint layer is not completely removed, the solution needs to be changed. When changing the solution, click the "drain" button of the submersible solvent instrument to discharge the waste liquid into the waste liquid bucket for collection. Then, insert the liquid inlet hose of the submersible solvent instrument into the plastic bucket containing the submersible solvent and click the "add liquid" button. The submersible solvent instrument will draw the submersible solvent into the paint stripping tank. When the calibrated liquid level is reached, the drawing will automatically stop.

8. The method for removing the enamel coating from ultra-fine diameter, fixed-length enameled copper wire via hydrolysis chemical reaction according to claim 1, characterized in that, The removed products are then cleaned and dried, as follows: Soak the removed product in anhydrous ethanol solution for more than 20 minutes, then clean the enameled copper wire with a brush, air dry it, and then put it in a constant temperature water bath oven at (60±2)℃ to dry for 2 hours.

9. The method for removing the enamel coating from ultra-fine diameter, fixed-length enameled copper wire via hydrolysis chemical reaction according to claim 1, characterized in that, The term "extremely fine wire diameter" refers to a diameter of less than 1 mm.

10. The method for removing the enamel coating from ultra-fine diameter, fixed-length enameled copper wire via hydrolysis chemical reaction according to claim 1, characterized in that, The limiting fixture can load multiple products at the same time, enabling simultaneous paint removal from multiple products.

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