阅读说明：本技术 一种mw级风电铜排的焊接工艺 (Welding process of MW-level wind power copper bar ) 是由 杨帆 庾高峰 马明月 宁超 靖林 曹延江 于 2021-07-09 设计创作，主要内容包括：本发明涉及风电铜排加工制造技术领域,具体是涉及一种MW级风电铜排的焊接工艺；具体包括以下步骤：制备石墨电极块：根据风电铜排和焊翅A焊接部位的形状、尺寸,制备两个石墨电极块A；采用两个石墨电极块从两侧对风电铜排和焊翅A焊接部位进行夹持；使得石墨电极块与风电铜排、焊翅A平面贴合；安装石墨电极块；装配焊翅：将风电铜排置于两个石墨电极块A之间,再通过焊翅A焊接定位工装,依次将焊片和焊翅A搭接在风电铜排上面；焊翅的电阻加热钎焊；能够有效解决现有技术在焊接过程中由于风电铜排受热不均导致变形量大,其焊缝质量差的问题。(The invention relates to the technical field of processing and manufacturing of wind power copper bars, in particular to a welding process of a MW-level wind power copper bar; the method specifically comprises the following steps: preparing a graphite electrode block: preparing two graphite electrode blocks A according to the shape and the size of the welding part of the wind power copper bar and the welding fin A; clamping the welding position of the wind power copper bar and the welding fin A from two sides by adopting two graphite electrode blocks; so that the graphite electrode block is attached to the planes of the wind power copper bar and the welding fin A; installing a graphite electrode block; assembling welding wings: placing the wind power copper bar between two graphite electrode blocks A, welding and positioning the tooling through a welding fin A, and overlapping a soldering lug and the welding fin A on the wind power copper bar in sequence; resistance heating brazing of the welding fin; the problem that the deformation is large and the quality of a welding seam is poor due to uneven heating of the wind power copper bar in the welding process in the prior art can be effectively solved.)

1. A welding process of a MW-level wind power copper bar is characterized in that a graphite electrode block is adopted to clamp and weld positions of the wind power copper bar and welding fins to be welded;

the method specifically comprises the following steps:

the method comprises the following steps: preparation of graphite electrode block

Preparing two graphite electrode blocks A according to the shape and the size of the welding part of the wind power copper bar and the welding fin A;

clamping the welding position of the wind power copper bar and the welding fin A from two sides by adopting two graphite electrode blocks; so that the graphite electrode block is attached to the planes of the wind power copper bar and the welding fin A;

step two: installing graphite electrode block

Respectively installing the two graphite electrode blocks A prepared in the step one on two conductive electrodes of resistance heating equipment; the two graphite electrode blocks A are correspondingly arranged; one graphite electrode block A is connected with an equipment power mechanism;

step three: assembly welding fin

Placing the wind power copper bar between two graphite electrode blocks A, welding and positioning the tooling through a welding fin A, overlapping a soldering lug and the welding fin A on the wind power copper bar in sequence, and applying pressure to the graphite electrode blocks A through a power mechanism to enable the graphite electrode blocks A to be attached to the welding fin A and the plane of a region to be welded of the wind power copper bar; after the graphite electrode block A is compressed, the welding positioning tool is taken out;

step four: resistance heating brazing of welded fins

Starting resistance heating equipment, and carrying out heating brazing under a certain current until the solder at the joint is completely melted to form a full weld joint;

step five: cooling and cleaning

And after welding the welding fin A, cooling by water at room temperature, and cleaning in a pickling solution.

2. The welding process of the MW-grade wind power copper bar according to claim 1, wherein the pickling solution in the fifth step comprises the following raw materials in parts by weight: 5-8 parts of hydrofluoric acid, 4-6 parts of oxidant, 3-5 parts of corrosion inhibitor, 0.5-0.8 part of sodium persulfate and 0.5-0.8 part of ammonium persulfate.

3. The welding process of the MW-grade wind power copper bar according to claim 1, wherein the cleaning process in the fifth step is: and soaking the whole workpiece welded with the wind power copper bar and the welding fin A in a pickling solution for 15-60 min, taking out, cleaning with a stainless steel wire brush, and wiping the surface of the workpiece with scouring cloth.

4. The welding process of the MW-grade wind power copper busbar according to claim 1, wherein when the welding fin B is welded on the wind power copper busbar obtained in the fifth step again, two graphite electrode blocks B are prepared according to the method for preparing the graphite electrode block A, and the graphite electrode block A in the second step is replaced;

the graphite electrode block B is provided with a sunken area in which the welding fin A can be embedded;

the welding fin B is lapped on the wind power copper bar by adopting a welding fin B welding positioning tool, the graphite electrode block B is pressed on a to-be-welded area of the welding fin B and is compressed by a power mechanism, and then the welding fin B welding positioning tool is pulled out; and sequentially carrying out resistance heating brazing, cooling and cleaning.

5. The welding process of the MW-grade wind power copper bar according to claim 4, wherein the graphite electrode block A and the graphite electrode block B are both subjected to antioxidant dipping treatment; the depressed areas on the graphite electrode block A and the graphite electrode block B are obtained by machining through a precise CNC machine tool;

the antioxidant comprises the following components in parts by weight: 26-30 parts of nano ceramic powder, 23-28 parts of nano aluminum oxide, 22-26 parts of nano silicon oxide, 6-9 parts of nano boron nitride, 2-3 parts of sodium oxide, 3-5 parts of calcium oxide, 10-15 parts of silicic acid and the balance of water;

the dipping treatment method comprises the following steps: soaking the graphite electrode block A and the graphite electrode block B in an antioxidant solution with the mass concentration of 10-15% for 50-80 min; the temperature condition is 150-180 ℃; carrying out ultrasonic continuous treatment for 30-60 min after soaking is started; and after the soaking is finished, drying at the temperature of 80-90 ℃.

6. The welding process of the MW-grade wind power copper bar according to claim 4, wherein the welding fin B welding positioning tool is assembled and connected with the fixed limiting cushion block through a sliding groove on the fixed limiting cushion block; the welding fin B welding positioning tool is provided with a positioning groove for placing a welding sheet and a welding fin B;

the fixed limiting cushion block comprises a cambered surface limiting block, two thickness limiting blocks and a bolt for connecting the cambered surface limiting block and the two thickness limiting blocks;

the arc radius of the cambered surface limiting block is the same as that of the wind power copper bar; the thickness of the two thickness limiting blocks is the same as that of the welding fin B;

and the two thickness limiting blocks are respectively provided with a sliding chute connected with the welding positioning tool for the welding fin B.

7. The welding process of the MW-grade wind power copper bar according to claim 6, wherein the welding fin B welding positioning tool, the cambered surface limiting block and the thickness limiting block are all stainless steel pieces.

8. The welding process of the MW-grade wind power copper busbar according to claim 1, wherein the soldering lug in the third step is a microcrystalline copper-based brazing alloy soldering lug.

9. The welding process of the MW-grade wind power copper bar according to claim 1, wherein the power mechanism in the second step is a hydraulic power system.

Technical Field

The invention relates to the technical field of processing and manufacturing of wind power copper bars, in particular to a welding process of a MW-level wind power copper bar.

Background

With the promotion of the global 'carbon peak reaching' and 'carbon neutralization' target plans, the clean and low-carbon development of an energy system is in the trend. Wind power is an important clean low-carbon energy system, and a new high tide of rapid development is about to be met. The wind power copper bar is used as a key electrical connection component in the wind generating set and generally plays the roles of converging, conducting and stabilizing current.

The commonly used MW-grade wind power row welding structure is as follows: the middle part of the main copper bar is a main copper bar, a large welding fin with larger dimension is welded on the upper part of the main copper bar at the same longitudinal position, and a small welding fin with smaller dimension is welded on the lower part of the main copper bar;

the wind power copper bar and the welding fin are usually welded on a welding platform directly in the prior art, the deformation is large due to uneven heating in the welding process, the quality of a welding seam is poor, the porosity in the metallographic phase of the welding seam is high, the conductivity is low, and the strength is greatly reduced.

Disclosure of Invention

The technical problem solved by the invention is as follows: the welding fins and the wind power copper bar are welded by the existing welding process to form welding seams with poor quality, and the deformation of the welding portions is large.

The technical scheme of the invention is as follows: a welding process of a MW-level wind power copper bar is characterized in that a graphite electrode block is adopted to clamp and weld positions of the wind power copper bar and welding wings to be welded;

the method specifically comprises the following steps:

the method comprises the following steps: preparation of graphite electrode block

Preparing two graphite electrode blocks according to the shape and the size of the welding part of the wind power copper bar and the welding fin A;

clamping the welding position of the wind power copper bar and the welding fin A from two sides by adopting two graphite electrode blocks; so that the graphite electrode block is attached to the planes of the wind power copper bar and the welding fin A;

step two: installing graphite electrode block

Respectively installing the two graphite electrode blocks A prepared in the step one on two conductive electrodes of resistance heating equipment; the two graphite electrode blocks A are correspondingly arranged; one graphite electrode block A is connected with an equipment power mechanism;

step three: assembly welding fin

Placing the wind power copper bar between two graphite electrode blocks A, welding and positioning the tooling through a welding fin A, overlapping a soldering lug and the welding fin A on the wind power copper bar in sequence, and applying pressure to the graphite electrode blocks A through a power mechanism to enable the graphite electrode blocks A to be attached to the welding fin A and the plane of a region to be welded of the wind power copper bar; after the graphite electrode block A is compressed, the welding positioning tool is taken out;

step four: resistance heating brazing of welded fins

Starting resistance heating equipment, and carrying out heating brazing under a certain current until the solder at the joint is completely melted to form a full weld joint;

step five: cooling and cleaning

And after welding the welding fin A, cooling by water at room temperature, and cleaning in a pickling solution.

Further, the pickling solution in the fifth step comprises the following raw material components in parts by weight: 5-8 parts of hydrofluoric acid, 4-6 parts of oxidant, 3-5 parts of corrosion inhibitor, 0.5-0.8 part of sodium persulfate and 0.5-0.8 part of ammonium persulfate. The components are mixed to obtain the efficient corrosion inhibition pickling cleaning solution, so that the oxide and various dirt on the surface of the welding line can be rapidly removed, the welding line can quickly present the natural color of metal, and the surface of a workpiece cannot be corroded and damaged in the cleaning process.

Further, the cleaning process in the fifth step is as follows: and soaking the whole workpiece welded with the wind power copper bar and the welding fins in a pickling solution for 15-60 min, taking out, cleaning with a stainless steel wire brush, and wiping the surface of the workpiece with scouring cloth. After the stainless steel wire brush is soaked in the acid liquor, oxides and various dirt on the surface of the welding line can be cleaned up by adopting the stainless steel wire brush for cleaning, so that the surface of the welding line is clean and bright.

Further, when the welding fins B are welded on the wind power copper bar obtained in the fifth step again, two graphite electrode blocks B are prepared according to the method for preparing the graphite electrode block A, and the graphite electrode block A in the second step is replaced;

the graphite electrode block B is provided with a sunken area in which the welding fin A can be embedded;

the welding fin B is lapped on the wind power copper bar by adopting a welding fin B welding positioning tool, the graphite electrode block B is pressed on a to-be-welded area of the welding fin B and is compressed by a power mechanism, and then the welding fin B welding positioning tool is pulled out; and sequentially carrying out resistance heating brazing, cooling and cleaning.

The welding sequence can ensure that the welding seams between the welding fin A and the wind power copper bar and between the welding fin B and the wind power copper bar are filled better and are fuller, and the welding seam quality is better; meanwhile, the total thickness change of the welding joint is effectively controllable after the wind power copper bar, the welding fin A and the welding fin B are heated and welded.

Further, the graphite electrode block A and the graphite electrode block B are subjected to antioxidant dipping treatment; the depressed areas on the graphite electrode block A and the graphite electrode block B are obtained by machining through a precise CNC machine tool;

the antioxidant comprises the following components in parts by weight: 26-30 parts of nano ceramic powder, 23-28 parts of nano aluminum oxide, 22-26 parts of nano silicon oxide, 6-9 parts of nano boron nitride, 2-3 parts of sodium oxide, 3-5 parts of calcium oxide, 10-15 parts of silicic acid and the balance of water;

the dipping treatment method comprises the following steps: soaking the graphite electrode block A and the graphite electrode block B in an antioxidant solution with the mass concentration of 10-15% for 50-80 min; the temperature condition is 150-180 ℃; carrying out ultrasonic continuous treatment for 30-60 min after soaking is started; and after the soaking is finished, drying at the temperature of 80-90 ℃.

The graphite electrode block A and the graphite electrode block B can be prevented from volatilizing easily in the continuous welding process through the treatment of the antioxidant, so that the surface of the graphite block is kept flat, and the workpiece is heated uniformly while the graphite block is repeatedly used.

Further, the welding fin B welding positioning tool is assembled and connected with the fixed limiting cushion block through a sliding groove in the fixed limiting cushion block; the welding fin B welding positioning tool is provided with a positioning groove for placing a welding sheet and a welding fin B;

the fixed limiting cushion block comprises a cambered surface limiting block, two thickness limiting blocks and a bolt for connecting the cambered surface limiting block and the two thickness limiting blocks;

the arc radius of the cambered surface limiting block is the same as that of the wind power copper bar; the thickness of the two thickness limiting blocks is the same as that of the welding fin B;

and the two thickness limiting blocks are respectively provided with a sliding chute connected with the welding positioning tool for the welding fin B.

Through the arrangement, two side edges of the welding wing B welding positioning tool can be inserted into the fixed limiting cushion blocks along two sliding grooves, and the fixing limiting cushion blocks can be rapidly pulled out before welding, so that the welding efficiency is improved.

Further, the welding wing B welding positioning tool, the cambered surface limiting block and the thickness limiting block are all stainless steel pieces. The stainless steel part is high in strength and convenient to process, can be repeatedly used, and is high in practicability.

Further, the soldering lug in the third step is a microcrystalline copper-based brazing alloy soldering lug; the micro-crystal copper-based brazing alloy soldering lug can ensure that a welding seam formed by the welded welding fin and the wind power copper bar is good in compactness and high in strength.

Furthermore, the power mechanism in the second step adopts a hydraulic power system; the graphite electrode block can be in close contact with the wind power copper bar through a hydraulic power system, so that the welding part can be effectively clamped; and the hydraulic power system is convenient to control and has strong operability.

The invention has the beneficial effects that: the application discloses a welding process of MW-level wind power copper bars, which is characterized in that graphite electrode blocks are adopted to clamp positions to be welded of the wind power copper bars and welding fins, and then resistance heating brazing is carried out; in the welding process, after a sunken area arranged in the graphite electrode block is in contact with the surface of a workpiece, the welding part is uniformly heated by utilizing the good heat conduction performance of the sunken area, the deformation of a wind power copper bar and a welding fin caused by welding is greatly reduced, and the welding positioning tool and the fixed limiting cushion block are combined to realize accurate welding; under the dual functions of pressure and temperature, the welding seam is effectively controllable, and the deformation is reduced; the welding method can ensure that the welding seam is even and full, so that the welding strength is greatly improved.

Drawings

FIG. 1 is a schematic view of a welding jig structure according to embodiment 1 of the present invention;

FIG. 2 is a schematic view of a welding jig structure according to embodiment 2 of the present invention;

FIG. 3 is a schematic structural diagram of the welding completion of the wind power copper bar in embodiment 2 of the invention;

Detailed Description

Example 1:

a welding process of a MW-level wind power copper bar specifically comprises the following steps:

the method comprises the following steps: preparation of graphite electrode block

Preparing two graphite electrode blocks A according to the shape and the size of the welding part of the wind power copper bar and the welding fin A;

clamping the welding position of the wind power copper bar and the welding fin A from two sides by adopting two graphite electrode blocks A; so that the graphite electrode block is attached to the planes of the wind power copper bar and the welding fin A;

the cross section of the wind power copper bar is 10mm in thickness and 40mm in width; the cross section size of the welding fin A is as follows: thickness 10mm and width 60 mm;

step two: installing graphite electrode block

Respectively installing the two graphite electrode blocks A prepared in the step one on two conductive electrodes of resistance heating equipment; the two graphite electrode blocks A are correspondingly arranged; one graphite electrode block A is connected with an equipment power mechanism;

step three: assembly welding fin

Placing the wind power copper bar between two graphite electrode blocks A, welding and positioning the tooling through a welding fin A, overlapping a soldering lug and the welding fin A on the wind power copper bar in sequence, and applying pressure to the graphite electrode blocks A through a power mechanism to enable the graphite electrode blocks A to be attached to the welding fin A and the plane of a region to be welded of the wind power copper bar; after the graphite electrode block A is compressed, the welding positioning tool is taken out;

step four: resistance heating brazing of welded fins

Starting resistance heating equipment, and carrying out heating brazing under the conditions of current 15KA and pressure 1MPa until the welding flux at the joint is completely melted to form a full welding seam;

step five: cooling and cleaning

And after welding the welding fin A, cooling by water at room temperature, and cleaning in a pickling solution.

The pickling solution comprises the following raw materials in parts by weight: 5 parts of hydrofluoric acid, 4 parts of oxidant, 3 parts of corrosion inhibitor, 0.5 part of sodium persulfate and 0.5 part of ammonium persulfate.

The cleaning process comprises the following steps: and soaking the whole workpiece welded with the wind power copper bar and the welding fin A in a pickling solution for 30min, taking out, cleaning with a stainless steel wire brush, and wiping the surface of the workpiece with scouring cloth.

Example 2:

a welding process of a MW-level wind power copper bar specifically comprises the following steps:

the method comprises the following steps: preparation of graphite electrode block

Preparing two graphite electrode blocks A according to the shape and the size of the welding part of the wind power copper bar and the welding fin A;

clamping the welding position of the wind power copper bar and the welding fin A from two sides by adopting two graphite electrode blocks A; so that the graphite electrode block is attached to the planes of the wind power copper bar and the welding fin A;

the cross section of the wind power copper bar is 10mm in thickness and 40mm in width; the cross section size of the welding fin A is as follows: thickness 10mm and width 60 mm;

step two: installing graphite electrode block

Respectively installing the two graphite electrode blocks A prepared in the step one on two conductive electrodes of resistance heating equipment; the two graphite electrode blocks A are correspondingly arranged; one graphite electrode block A is connected with an equipment power mechanism;

step three: assembly welding fin

Placing the wind power copper bar between two graphite electrode blocks A, welding and positioning the tooling through a welding fin A, overlapping a soldering lug and the welding fin A on the wind power copper bar in sequence, and applying pressure to the graphite electrode blocks A through a power mechanism to enable the graphite electrode blocks A to be attached to the welding fin A and the plane of a region to be welded of the wind power copper bar; after the graphite electrode block A is compressed, the welding positioning tool is taken out;

step four: resistance heating brazing of welded fins

Starting resistance heating equipment, and carrying out heating brazing under the conditions of current 14.8KA and pressure 1.1MPa until the solder at the joint is completely melted to form a full weld joint;

step five: cooling and cleaning

And after welding the welding fin A, cooling by water at room temperature, and cleaning in a pickling solution.

The pickling solution comprises the following raw materials in parts by weight: 8 parts of hydrofluoric acid, 6 parts of oxidant, 5 parts of corrosion inhibitor, 0.8 part of sodium persulfate and 0.8 part of ammonium persulfate.

The cleaning process comprises the following steps: and soaking the whole workpiece welded with the wind power copper bar and the welding fin A in a pickling solution for 25min, taking out, cleaning with a stainless steel wire brush, and wiping the surface of the workpiece with scouring cloth.

Step six: re-welding

When the welding fins B are welded on the wind power copper bar obtained in the fifth step again, two graphite electrode blocks B are prepared according to the method for preparing the graphite electrode block A, and the graphite electrode block A in the second step is replaced; the cross-sectional area of the welding fin B is as follows: thickness 5mm and width 12 mm;

the graphite electrode block B is provided with a sunken area in which the welding fin A can be embedded; the welding fin B is lapped on the wind power copper bar by adopting a welding fin B welding positioning tool;

the method comprises the following steps: the fixed limiting cushion block consists of a cambered surface limiting block, two thickness limiting blocks and a bolt for connecting the cambered surface limiting block and the two thickness limiting blocks; the thickness limiting blocks are respectively provided with a sliding chute;

the welding wing B welding positioning tool is assembled and connected with the fixed limiting cushion block through a sliding groove in the thickness limiting cushion block; placing the soldering lug and the soldering fin B into a positioning groove of a soldering fin B welding positioning tool;

the graphite electrode block B is pressed on the area to be welded of the welding fin B and is pressed tightly by a power mechanism,

then, the welding wing B is pulled out along the sliding groove to weld and position the tool; carrying out resistance heating brazing under the conditions of current 12KA and pressure of 0MPa, and finally cooling and cleaning.

Wherein, the graphite electrode block A and the graphite electrode block B are both subjected to antioxidant dipping treatment; the depressed areas on the graphite electrode block A and the graphite electrode block B are obtained by machining through a precise CNC machine tool;

the antioxidant comprises the following components in parts by weight: 26 parts of nano ceramic powder, 23 parts of nano aluminum oxide, 22 parts of nano silicon oxide, 6 parts of nano boron nitride, 2 parts of sodium oxide, 3 parts of calcium oxide, 10 parts of silicic acid and the balance of water;

the dipping treatment method comprises the following steps: soaking the graphite electrode block A and the graphite electrode block B in an antioxidant solution with the mass concentration of 10% for 50 min; the temperature condition is 150 ℃; continuously treating for 30min by using ultrasonic after soaking; after the soaking is finished, drying at the temperature of 80 ℃.

Example 3:

a welding process of a MW-level wind power copper bar specifically comprises the following steps:

the method comprises the following steps: preparation of graphite electrode block

Preparing two graphite electrode blocks A according to the shape and the size of the welding part of the wind power copper bar and the welding fin A;

clamping the welding position of the wind power copper bar and the welding fin A from two sides by adopting two graphite electrode blocks A; so that the graphite electrode block is attached to the planes of the wind power copper bar and the welding fin A;

the cross section of the wind power copper bar is 10mm in thickness and 40mm in width; the cross section size of the welding fin A is as follows: thickness 10mm and width 60 mm;

step two: installing graphite electrode block

Respectively installing the two graphite electrode blocks A prepared in the step one on two conductive electrodes of resistance heating equipment; the two graphite electrode blocks A are correspondingly arranged; one graphite electrode block A is connected with an equipment power mechanism;

step three: assembly welding fin

Placing the wind power copper bar between two graphite electrode blocks A, welding and positioning the tooling through a welding fin A, overlapping a soldering lug and the welding fin A on the wind power copper bar in sequence, and applying pressure to the graphite electrode blocks A through a power mechanism to enable the graphite electrode blocks A to be attached to the welding fin A and the plane of a region to be welded of the wind power copper bar; after the graphite electrode block A is compressed, the welding positioning tool is taken out;

step four: resistance heating brazing of welded fins

Starting resistance heating equipment, and carrying out heating brazing under the conditions of current 14.5KA and pressure 1.2MPa until the solder at the joint is completely melted to form a full weld joint;

step five: cooling and cleaning

And after welding the welding fin A, cooling by water at room temperature, and cleaning in a pickling solution.

The pickling solution comprises the following raw materials in parts by weight: 6 parts of hydrofluoric acid, 5 parts of oxidant, 4 parts of corrosion inhibitor, 0.68 part of sodium persulfate and 0.6 part of ammonium persulfate.

The cleaning process comprises the following steps: and soaking the whole workpiece welded with the wind power copper bar and the welding fin A in a pickling solution for 50min, taking out, cleaning with a stainless steel wire brush, and wiping the surface of the workpiece with scouring cloth.

Step six: re-welding

When the welding fins B are welded on the wind power copper bar obtained in the fifth step again, two graphite electrode blocks B are prepared according to the method for preparing the graphite electrode block A, and the graphite electrode block A in the second step is replaced; the size of the cross section area of the welding fin B is as follows: thickness 5mm and width 12 mm;

the graphite electrode block B is provided with a sunken area in which the welding fin A can be embedded;

the welding fin B is lapped on the wind power copper bar by adopting a welding fin B welding positioning tool;

the method comprises the following steps: the fixed limiting cushion block consists of a cambered surface limiting block, two thickness limiting blocks and a bolt for connecting the cambered surface limiting block and the two thickness limiting blocks; the thickness limiting blocks are respectively provided with a sliding chute;

the welding wing B welding positioning tool is assembled and connected with the fixed limiting cushion block through a sliding groove in the thickness limiting cushion block; placing the soldering lug and the soldering fin B into a positioning groove of a soldering fin B welding positioning tool;

the graphite electrode block B is pressed on the area to be welded of the welding fin B and is pressed tightly by a power mechanism,

then, the welding wing B is pulled out along the sliding groove to weld and position the tool; carrying out resistance heating brazing under the conditions of current of 12.2KA and pressure of 0.3MPa, and finally cooling and cleaning.

Wherein, the graphite electrode block A and the graphite electrode block B are both subjected to antioxidant dipping treatment; the depressed areas on the graphite electrode block A and the graphite electrode block B are obtained by machining through a precise CNC machine tool;

the antioxidant comprises the following components in parts by weight: 30 parts of nano ceramic powder, 28 parts of nano aluminum oxide, 26 parts of nano silicon oxide, 9 parts of nano boron nitride, 3 parts of sodium oxide, 5 parts of calcium oxide, 15 parts of silicic acid and the balance of water;

the dipping treatment method comprises the following steps: soaking the graphite electrode block A and the graphite electrode block B in an antioxidant solution with the mass concentration of 15% for 80 min; the temperature condition is 180 ℃; continuously treating for 60min with ultrasound after soaking; after the soaking is finished, drying at 90 ℃.

Experimental example: detecting the wind power copper bar obtained by welding in the embodiments 1-3, and specifically performing UT ultrasonic flaw detection, macroscopic metallographic detection and conductivity detection; the experimental data were recorded as follows in table 1:

table 1: embodiment 1-3 detection of performance of welded wind power copper bar

Examples	Interface wave (%)	Porosity (%)	Electrical conductivity (% IACS)
				Example 1	10	8	102
Example 2	9.5	7.6	103
				Example 3	9.3	7.5	105

According to the detection data, when UT ultrasonic flaw detection is carried out, the interfacial wave at the double-welding-fin joint is less than or equal to 10%; when macroscopic metallographic examination is carried out, the porosity in the welding seam is less than or equal to 8 percent; when the electric conductivity is detected, the electric conductivity of the double-welded-fin joint is more than or equal to 100% IACS; therefore, the welding process for welding the wind power copper bar and the welding fins can ensure the quality of welding seams and obtain the welded wind power copper bar with good quality and high strength.

The comparison shows that the embodiment 3 is the best embodiment of the above schemes; the porosity and the conductivity of the welding seam are the minimum and the highest, so that the quality of the welding seam is ensured.