Method for removing surface oxide layer of ground wire and controller

Abstract

The application provides a method for removing surface oxide layer of a ground wire, comprising determining a laser and a ground wire corresponding to a surface oxide layer to be removed; driving the laser to emit pulsed laser with a first specified spot coverage and energy density to remove the surface oxide layer of the ground wire until the proportion of the area not removed is less than or equal to a first percentage; then, driving the laser to emit continuous laser with a predetermined process parameter combination to remove the surface oxide layer of the ground wire until the proportion of the area not removed is less than or equal to a second percentage; finally, driving the laser to emit pulsed laser with a second specified spot coverage and energy density to remove the surface oxide layer of the ground wire until the proportion of the area not removed is less than or equal to a third percentage. The application can solve the problems of time-consuming, labor-consuming and incomplete cleaning caused by the traditional cleaning methods of steel brush, sandpaper and gasoline, and reduce the probability of the ground wire breakage.

Description

Technical Field

[0001] This invention relates to the field of power maintenance technology, and in particular to a method and controller for removing oxide layers from the surface of conductors and ground wires. Background Technology

[0002] In the construction of overhead transmission lines, the connection between two adjacent conductors is achieved by a hydraulically driven clamp that moves up and down to crimp the sleeves covering the two conductors together. However, the quality of conductor crimping is a crucial aspect of the overhead line construction, directly impacting the stability and safe operation of the power grid. Therefore, during conductor crimping, it is essential to thoroughly clean any adhering substances and oxide layers from the conductor surface to reduce the contact resistance between the conductor and the splice sleeve and tension sleeve. This prevents excessive energy consumption during line operation due to high contact resistance of the splice sleeve, thereby improving power supply stability and continuity.

[0003] Currently, conductors and ground wires are cleaned using steel brushes, sandpaper, or gasoline to remove surface deposits and oxide layers. For example, for old conductors and ground wires in operation, a fine steel wire brush is used to remove black deposits until the aluminum strands and steel core surfaces have a metallic luster; or, if the conductors and ground wires are free of oil, they are wiped clean with cotton yarn; or, before connecting conductors and ground wires, gasoline is used to clean the surface of the connection parts, the inner wall of the connecting pipe, and the surface of the conductors that the connecting pipe may come into contact with during pipe installation.

[0004] However, the traditional cleaning methods mentioned above, such as using steel brushes, sandpaper, and gasoline, are all time-consuming, labor-intensive, and not thorough enough, which can easily lead to the ground wire breaking. Summary of the Invention

[0005] The technical problem to be solved by the embodiments of the present invention is to provide a method and controller for removing the oxide layer on the surface of the ground wire, which can solve the problems of time-consuming, labor-intensive and incomplete cleaning caused by traditional cleaning methods such as steel brushes, sandpaper and gasoline, and reduce the probability of ground wire breakage.

[0006] To address the aforementioned technical problems, embodiments of the present invention provide a method for removing the oxide layer from the surface of a ground wire, the method comprising the following steps:

[0007] Determine the ground wire of the laser and its corresponding surface oxide layer to be removed;

[0008] The laser is driven to emit pulsed laser with a first specified spot coverage and a first specified energy density to remove the surface oxide layer from the ground wire until the proportion of the area on the ground wire where the surface oxide layer has not been completely removed is less than or equal to a preset first percentage.

[0009] If the proportion of the area where the surface oxide layer has not been removed is less than or equal to the first percentage value, the laser is driven to emit a continuous laser using a predetermined combination of process parameters to remove the surface oxide layer from the ground wire until the proportion of the area on the ground wire where the surface oxide layer has not been removed is less than or equal to the preset second percentage.

[0010] If the proportion of the area where the surface oxide layer has not been removed is less than or equal to the second percentage value, the laser is driven to emit pulsed laser with a second specified spot coverage and a second specified energy density to remove the surface oxide layer from the ground wire until the proportion of the area on the ground wire where the surface oxide layer has not been removed is less than or equal to the preset third percentage.

[0011] Wherein, the second percentage is less than the first percentage and greater than the third percentage; the second specified spot coverage is less than the first specified spot coverage; and the second specified energy density is less than the first specified energy density.

[0012] The process parameter combination includes a laser power of 75W / cm². 2 The pulse repetition frequency was 0.4MHz, the spot overlap rate and the scan trajectory overlap rate were both 35%, and the number of cyclic scans was 15.

[0013] Wherein, the first percentage is 10%; the second percentage is 5%; and the third percentage is 1%.

[0014] Wherein, the first specified spot coverage is such that the spot diameter is between 6mm and 7mm, and the first specified energy density is 1.1J / cm². 2 The second specified spot coverage is a spot diameter between 5mm and 6mm, and the first specified energy density is 0.8J / cm². 2 .

[0015] This invention also provides a controller, comprising:

[0016] The target determination unit is used to determine the laser and its corresponding ground wire for the oxide layer on the surface to be removed;

[0017] The high-density mode oxide removal unit is used to drive the laser to emit pulsed laser with a first specified spot coverage and a first specified energy density to remove the surface oxide layer on the ground wire until the proportion of the area on the ground wire where the surface oxide layer has not been completely removed is less than or equal to a preset first percentage.

[0018] The medium-density mode oxide removal unit is used to drive the laser to emit continuous laser using a predetermined process parameter combination if the proportion of the area of ​​the uncleaned surface oxide layer detected is less than or equal to the first percentage value, so as to remove the surface oxide layer by aligning it with the ground wire until the proportion of the area of ​​the uncleaned surface oxide layer on the ground wire is less than or equal to the preset second percentage.

[0019] The low-density mode oxide removal unit is used to drive the laser to emit pulsed laser with a second specified spot coverage and a second specified energy density if the proportion of the area on the ground wire where the surface oxide layer is not removed is less than or equal to the second percentage value. This pulsed laser is then directed to remove the surface oxide layer from the ground wire until the proportion of the area on the ground wire where the surface oxide layer is not removed is less than or equal to the preset third percentage.

[0020] Wherein, the second percentage is less than the first percentage and greater than the third percentage; the second specified spot coverage is less than the first specified spot coverage; and the second specified energy density is less than the first specified energy density.

[0021] The process parameter combination includes a laser power of 75W / cm². 2 The pulse repetition frequency was 0.4MHz, the spot overlap rate and the scan trajectory overlap rate were both 35%, and the number of cyclic scans was 15.

[0022] Wherein, the first percentage is 10%; the second percentage is 5%; and the third percentage is 1%.

[0023] Wherein, the first specified spot coverage is such that the spot diameter is between 6mm and 7mm, and the first specified energy density is 1.1J / cm². 2 The second specified spot coverage is a spot diameter between 5mm and 6mm, and the first specified energy density is 0.8J / cm². 2 .

[0024] Implementing the embodiments of the present invention has the following beneficial effects:

[0025] This invention employs a laser with a first specified spot coverage and a first specified energy density (i.e., high spot coverage and high energy density) to remove most of the rust layer. Then, it uses the optimal combination of process parameters obtained from single-factor experiments to remove most of the remaining oxide layer. Finally, it uses a second specified spot coverage and a second specified energy density (i.e., low spot coverage and low energy density) to perform a final finishing rust removal strategy on the conductor surface. This not only yields a more refined surface morphology but also improves the efficiency of oxide layer removal. This solves the problems of time-consuming, labor-intensive, and incomplete cleaning caused by traditional cleaning methods such as steel brushes, sandpaper, and gasoline, and reduces the probability of conductor breakage. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, obtaining other drawings based on these drawings without creative effort still falls within the scope of the present invention.

[0027] Figure 1 A flowchart of a method for removing the oxide layer on the surface of a ground wire, provided in an embodiment of the present invention;

[0028] Figure 2 This is a schematic diagram of the structure of a controller provided in an embodiment of the present invention. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings.

[0030] like Figure 1 As shown in the figure, a method for removing the oxide layer on the surface of a ground wire is proposed in an embodiment of the present invention. This method is implemented on a controller and includes the following steps:

[0031] Step S1: Determine the laser and its corresponding ground wire for the oxide layer on the surface to be removed;

[0032] Step S2: Drive the laser to emit pulsed laser with a first specified spot coverage and a first specified energy density to remove the surface oxide layer of the ground wire until the proportion of the area on the ground wire where the surface oxide layer has not been completely removed is less than or equal to a preset first percentage.

[0033] Step S3: If the proportion of the area where the surface oxide layer has not been removed is less than or equal to the first percentage value, then drive the laser to emit continuous laser using a predetermined combination of process parameters to remove the surface oxide layer from the ground wire until the proportion of the area on the ground wire where the surface oxide layer has not been removed is less than or equal to a preset second percentage; wherein the second percentage is less than the first percentage.

[0034] Step S4: If the proportion of the area where the surface oxide layer has not been removed is less than or equal to the second percentage value, then drive the laser to emit pulsed laser with the second specified spot coverage and the second specified energy density to remove the surface oxide layer on the ground wire until the proportion of the area where the surface oxide layer has not been removed on the ground wire is less than or equal to the preset third percentage.

[0035] Wherein, the second percentage is less than the first percentage and greater than the third percentage; the second specified spot coverage is less than the first specified spot coverage; and the second specified energy density is less than the first specified energy density.

[0036] The specific process is as follows: in step S1, the controller selects the driving laser and further determines the ground wire of the laser corresponding to the surface oxide layer to be removed.

[0037] In step S2, the laser is modulated by the controller to achieve a first specified spot coverage (e.g., spot diameter between 6mm and 7mm) and a first specified energy density (e.g., 1.1J / cm²). 2 The laser emits a pulsed laser and directs the modulated laser at the ground wire to remove the surface oxide layer until the proportion of the area on the ground wire where the surface oxide layer has not been completely removed is less than or equal to a preset first percentage (e.g., 10%). It should be noted that the laser uses a high spot coverage and high specified energy density. While this will completely remove the rust layer, it may also cause secondary oxidation on the workpiece surface, resulting in over-cleaning. Therefore, this high spot coverage and high specified energy density pulsed laser can remove most of the rust layer and allows for a certain degree of secondary oxidation, thus it cannot achieve a final smooth finish. Further detailed cleaning steps are required to improve the surface oxide layer removal efficiency.

[0038] Understandably, the areas on the conductor with clean surface oxide layer removed and the areas with unclean surface oxide layer removed can be obtained and judged by scanning with the laser front-end galvanometer and fed back to the controller, or obtained and fed back to the controller by other scanning equipment.

[0039] In step S3, it is considered that different process parameters (laser spot overlap rate and scanning trajectory overlap rate, average laser power, number of cycle scans, laser repetition frequency, etc.) have different influence patterns on the test results after rust removal when removing the oxide layer on the surface of the conductor ground wire by laser.

[0040] Therefore, after most of the oxide layer on the surface of the conductor is removed in step S2, the laser is modulated by the controller using a combination of process parameters, including a laser power of 75 W / cm². 2 The pulse repetition frequency is 0.4MHz, the spot overlap rate and the scanning trajectory overlap rate are both 35%, and the number of cyclic scans is 15. The continuous laser is emitted to aim at the ground wire to remove the surface oxide layer until the proportion of the area on the ground wire where the surface oxide layer has not been removed is less than or equal to a preset second percentage (such as 5%), so as to further enhance the efficiency of removing the surface oxide layer.

[0041] It should be noted that during laser rust removal, to ensure the oxide layer is removed uniformly, the surface must be evenly covered by the laser spot. To remove the rust layer evenly and efficiently without causing insufficient cleaning or secondary oxidation, appropriate laser spot overlap rates (the overlap rate of two adjacent laser spots on the same laser scanning trajectory) and laser scanning trajectory overlap rates (the overlap rate of two adjacent laser scanning trajectories on the circumferential surface of the grinding wheel) must be selected to ensure the pulsed laser spots are evenly distributed on the workpiece surface. In this case, both the laser spot overlap rate and the laser scanning trajectory overlap rate are selected between 30% and 40%.

[0042] Laser power density directly determines the removal effect and efficiency of the oxide layer through the laser energy deposited on it. Insufficient power density leads to incomplete rust removal, requiring multiple layers to completely remove the rust, resulting in low efficiency. While excessive power density removes the rust completely, it may also cause secondary oxidation on the workpiece surface, leading to over-cleaning. Therefore, when the average laser power is 75 W / cm²... 2 At this time, the rust layer on the workpiece surface can be completely removed without damaging the base material or causing secondary oxidation, leaving the surface bright and without obvious protrusions. However, the average power density is less than or greater than this power density of 75W / cm³. 2 In some cases, this can lead to incomplete rust removal or secondary oxidation on the workpiece surface.

[0043] When the number of scans is 4–12, the removal depth increases rapidly with the increase of the number of scans. This is because the laser is always removing the oxide layer on the workpiece surface without touching the metal substrate. The oxide layer is loose and porous and has a high absorption rate of laser light. Most of the laser energy is absorbed by the oxide layer, which expands due to heat and flies away from the workpiece surface. The resulting molten metal slag and metal alteration layer are relatively thin and have a limited impact on the material removal rate. However, when the number of scans is 16–24, the oxide layer has been basically removed, exposing a large area of ​​the metal substrate. When irradiated by high-energy laser, most of the energy generates a thicker, dense metal alteration layer, and molten droplets cover the substrate surface, forming surface defects. This hinders the removal depth of a single scan, and the increase in removal depth slows down with the continued increase of the number of scans. At this point, the number of scans is selected to be 12–16.

[0044] In step S4, considering that step S3 did not achieve the final smoothing effect of the conductor ground wire, it is also necessary to modulate the laser using a second specified spot coverage (e.g., spot diameter between 5mm and 6mm) and a second specified energy density (e.g., 0.8J / cm²). 2 The laser emits pulsed laser light and modulates it to remove the surface oxide layer from the ground wire until the proportion of the ground wire with incompletely removed surface oxide layer is less than or equal to a preset third percentage (e.g., 1%), thus achieving the final finishing effect on the ground wire. It should be noted that the second specified spot coverage and second specified energy density used by the laser are low spot coverage and low specified energy density, which can achieve the final finishing of the ground wire surface to meet the surface quality requirements of the workpiece.

[0045] At this point, the workpiece treated with laser rust removal has stronger corrosion resistance than the workpiece treated with sandpaper. This is because the dense altered layer on the surface of the workpiece after laser treatment prevents the metal substrate from contacting the corrosive air, while the metal marks left by the sandpaper on the metal substrate provide a larger contact area for the water film in the air, accelerating the corrosion rate of the substrate.

[0046] like Figure 2 As shown in the figure, a controller is provided in an embodiment of the present invention, comprising:

[0047] The target object determination unit 110 is used to determine the laser and its corresponding ground wire of the oxide layer to be removed from the surface;

[0048] The high-density mode oxide removal unit 120 is used to drive the laser to emit pulsed laser with a first specified spot coverage and a first specified energy density to remove the surface oxide layer on the ground wire until the proportion of the area on the ground wire where the surface oxide layer has not been completely removed is less than or equal to a preset first percentage.

[0049] The medium-density mode oxide removal unit 130 is used to drive the laser to emit continuous laser using a predetermined process parameter combination if the proportion of the area on the ground wire that has not been cleaned is less than or equal to the first percentage value, so as to remove the surface oxide layer by aligning it with the ground wire until the proportion of the area on the ground wire that has not been cleaned is less than or equal to the preset second percentage.

[0050] The low-density mode oxide removal unit 140 is used to drive the laser to emit pulsed laser with a second specified spot coverage and a second specified energy density if the proportion of the area on the ground wire that has not been cleaned is less than or equal to the second percentage value, so as to remove the surface oxide layer by aligning it with the ground wire until the proportion of the area on the ground wire that has not been cleaned is less than or equal to the preset third percentage.

[0051] Wherein, the second percentage is less than the first percentage and greater than the third percentage; the second specified spot coverage is less than the first specified spot coverage; and the second specified energy density is less than the first specified energy density.

[0052] The process parameter combination includes a laser power of 75W / cm². 2 The pulse repetition frequency was 0.4MHz, the spot overlap rate and the scan trajectory overlap rate were both 35%, and the number of cyclic scans was 15.

[0053] Wherein, the first percentage is 10%; the second percentage is 5%; and the third percentage is 1%.

[0054] Wherein, the first specified spot coverage is such that the spot diameter is between 6mm and 7mm, and the first specified energy density is 1.1J / cm². 2 The second specified spot coverage is a spot diameter between 5mm and 6mm, and the first specified energy density is 0.8J / cm². 2 .

[0055] Implementing the embodiments of the present invention has the following beneficial effects:

[0056] This invention employs a laser with a first specified spot coverage and a first specified energy density (i.e., high spot coverage and high energy density) to remove most of the rust layer. Then, it uses the optimal combination of process parameters obtained from single-factor experiments to remove most of the remaining oxide layer. Finally, it uses a second specified spot coverage and a second specified energy density (i.e., low spot coverage and low energy density) to perform a final finishing rust removal strategy on the conductor surface. This not only yields a more refined surface morphology but also improves the efficiency of oxide layer removal. This solves the problems of time-consuming, labor-intensive, and incomplete cleaning caused by traditional cleaning methods such as steel brushes, sandpaper, and gasoline, and reduces the probability of conductor breakage.

[0057] It is worth noting that in the above device embodiments, the various device modules are divided according to functional logic, but are not limited to the above division, as long as the corresponding functions can be achieved; in addition, the specific names of each functional module are only for easy differentiation and are not used to limit the scope of protection of the present invention.

[0058] Those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, such as ROM / RAM, disk, optical disk, etc.

[0059] The above description discloses only preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. Therefore, equivalent variations made in accordance with the claims of the present invention are still within the scope of the present invention.

Claims

1. A method of removing the surface oxide layer from a ground wire, comprising: The method comprises the following steps: determining a laser and a corresponding ground trace of a surface oxide layer to be removed; driving the laser to emit pulsed laser with a first specified spot coverage and a first specified energy density to remove the surface oxide layer of the ground trace until the proportion of the area of the ground trace where the surface oxide layer is not removed is less than or equal to a first preset percentage; if it is detected that the proportion of the area of the ground trace where the surface oxide layer is not removed is less than or equal to the first percentage, driving the laser to emit continuous laser with a predetermined process parameter combination to remove the surface oxide layer of the ground trace until the proportion of the area of the ground trace where the surface oxide layer is not removed is less than or equal to a second preset percentage; if it is detected that the proportion of the area of the ground trace where the surface oxide layer is not removed is less than or equal to the second percentage, driving the laser to emit pulsed laser with a second specified spot coverage and a second specified energy density to remove the surface oxide layer of the ground trace until the proportion of the area of the ground trace where the surface oxide layer is not removed is less than or equal to a third preset percentage; wherein the second percentage is less than the first percentage and greater than the third percentage; the second specified spot coverage is less than the first specified spot coverage; and the second specified energy density is less than the first specified energy density.

2. The method of claim 1, wherein the step of removing the oxide layer is performed by a method selected from the group consisting of: grinding, sanding, and polishing. The process parameter combination includes that the laser power is 75 W / cm 2 , the pulse repetition frequency is 0.4 MHz, the light spot overlap rate and the scanning track overlap rate are both 35%, and the cyclic scanning times are 15.

3. The method of claim 1, wherein the step of removing the oxide layer is performed by a method selected from the group consisting of: chemical etching, mechanical abrasion, and a combination thereof. The first percentage is 10%; the second percentage is 5%; and the third percentage is 1%.

4. The method of claim 1, wherein the step of removing the oxide layer is performed by a method selected from the group consisting of: chemical etching, mechanical abrasion, and a combination thereof. said first specified spot coverage is a spot diameter between 6 mm and 7 mm, said first specified fluence is 1.1 J / cm 2 ; said second specified spot coverage is a spot diameter between 5 mm and 6 mm, said first specified fluence is 0.8 J / cm 2 .

5. A controller characterized by comprising: It comprises: a target determination unit configured to determine a laser and a corresponding ground trace of a surface oxide layer to be removed; a high-density mode oxide layer removal unit configured to drive the laser to emit pulsed laser with a first specified spot coverage and a first specified energy density to remove the surface oxide layer of the ground trace until the proportion of the area of the ground trace where the surface oxide layer is not removed is less than or equal to a first preset percentage; a medium-density mode oxide layer removal unit configured to, if it is detected that the proportion of the area of the ground trace where the surface oxide layer is not removed is less than or equal to the first percentage, drive the laser to emit continuous laser with a predetermined process parameter combination to remove the surface oxide layer of the ground trace until the proportion of the area of the ground trace where the surface oxide layer is not removed is less than or equal to a second preset percentage; a low-density mode oxide layer removal unit configured to, if it is detected that the proportion of the area of the ground trace where the surface oxide layer is not removed is less than or equal to the second percentage, drive the laser to emit pulsed laser with a second specified spot coverage and a second specified energy density to remove the surface oxide layer of the ground trace until the proportion of the area of the ground trace where the surface oxide layer is not removed is less than or equal to a third preset percentage; wherein the second percentage is less than the first percentage and greater than the third percentage; the second specified spot coverage is less than the first specified spot coverage; and the second specified energy density is less than the first specified energy density.

6. The controller of claim 5, wherein, The process parameter combination includes that the laser power is 75 W / cm 2 , the pulse repetition frequency is 0.4 MHz, the light spot overlap rate and the scanning track overlap rate are both 35%, and the cyclic scanning times are 15.

7. The controller of claim 5, wherein, The first percentage is 10%; the second percentage is 5%; and the third percentage is 1%. The first percentage is 10%; the second percentage is 5%; and the third percentage is 1%. The first percentage is 10%; the second percentage is 5%; and the third percentage 8. The controller of claim 5, wherein, said first specified spot coverage is a spot diameter between 6 mm and 7 mm, said first specified fluence is 1.1 J / cm 2 said second specified spot coverage is a spot diameter between 5 mm and 6 mm, said first specified fluence is 0.8 J / cm 2 .

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