Production process of high-strength steel solid welding wire of 70 kg or below

Abstract

The invention relates to a production process of a high-strength steel solid welding wire with the weight of 70 kg or below, and the integrated production process is formed by integrating multiple procedures of paying off, mechanical husking, abrasive belt dephosphorization, first drawing, copper plating pretreatment, electric auxiliary copper plating, copper plating aftertreatment, second drawing and taking up. In addition, non-annealing drawing in production of solid welding wires of 70 kilograms or below is achieved, the original wire drawing process is improved and designed, and by means of roller die drawing and die drawing, the original area reduction rate is changed, and work hardening is reduced to the maximum extent. A chemical treatment mode of copper plating pretreatment is changed into a physical treatment mode, alkali electrolysis and acid electrolysis are omitted, the copper plating efficiency and the production efficiency are improved, meanwhile, the production cost is reduced, and the environment-friendly concept is implemented.

Description

Technical Field

[0001] The invention relates to the technical field of mechanical processing in the metallurgical industry, and in particular to a production process of high-strength steel solid welding wire below 70 kilograms. Background Art

[0002] It promotes the development of metal materials towards higher strength and higher performance. This trend not only promotes the lightweight process of many industries such as building structures, engineering equipment, automobiles, bridges, shipbuilding, and transportation, but also helps to reduce the use of steel materials and reduce energy consumption. The matching of welding materials is one of the key conditions for the application of high-strength steel. Due to the difficulty of research and development and production, it has become an important research topic in the field of materials and welding.

[0003] High-strength steel solid welding wire is quite difficult to produce due to its high strength and more complex chemical composition than ordinary solid welding wire. There is no unified chemical composition standard and each manufacturer has certain differences, resulting in large differences in the drawing properties of the raw materials produced.

[0004] The original production process includes the following five steps: 1. Annealing - pay-off - dephosphorization - die drawing - wire taking-up; 2. Pay-off - die drawing - water washing - wire taking-up; 3. Pay-off - water washing - alkaline electrolysis - acid electrolysis - chemical copper plating - water washing - neutralization - water washing - drying - fine drawing - wire taking-up; 4. Pay-off - layer winding; 5. Packaging. However, the above-mentioned production process has a high wire breakage rate and low production efficiency, which is not suitable for industrial production. Summary of the invention

[0005] The purpose of the present invention is to provide a production process for high-strength steel solid welding wire below 70 kg, so as to solve the problems of high wire breakage rate and low production efficiency in the production process of high-strength steel solid welding wire in the prior art.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is: The present invention provides a production process for high-strength steel solid welding wire below 70 kg, comprising the following steps: S1 Pay-off: Use double-station hydraulic pay-off stand to pay-off the welding wire raw materials; S2 Mechanical Shelling: Send the welding wire raw material after wire laying into a mechanical shelling machine for mechanical shelling, pretreat the oxide scale on the surface of the welding wire, and straighten the welding wire raw material synchronously; S3 abrasive belt dephosphorization: sending the welding wire raw material after mechanical shelling into the abrasive belt machine for dephosphorization to remove the oxide scale on the surface of the welding wire raw material; S4 first drawing: roller die drawing and die drawing are performed on the dephosphorized welding wire raw material in sequence to obtain a welding wire semi-finished product; S5 copper plating pretreatment: washing the semi-finished welding wire after the first drawing with hot water and high-pressure water in sequence; S6: electro-assisted copper plating: electro-assisted copper plating is performed on the semi-finished welding wire after the copper plating pre-treatment; S7 copper plating post-treatment: washing, neutralizing and secondary washing the welding wire semi-finished product after the electric assisted copper plating in sequence to remove residual acid and impurities on the surface of the welding wire semi-finished product; S8 second drawing: fine drawing the semi-finished welding wire after copper plating treatment to obtain the high-strength steel solid welding wire; S9: feeding the high-strength steel solid welding wire into a double-reel wire take-up machine for wire take-up.

[0007] Furthermore, the chemical composition of the applicable high-strength steel solid welding wire is calculated by weight percentage as follows: C≤0.11%, Mn: 1.4~1.8%, Si: 0.5~1%, P≤0.025%, S≤0.025%, Cr: 0.1~0.6%; Ni≤0.4%, Mo≤0.25%; Ti: ≤0.12%, the balance being Fe and unavoidable impurities.

[0008] Furthermore, in step S3, the mesh number of the sanding belt is 60 meshes, and the rotation speed of the sanding belt is 1200-2400 r / min.

[0009] Furthermore, in step S4, the roller die pulling speed is 12-15 m / min; the die pulling speed is 6-8 m / min.

[0010] Furthermore, in step S4, the average surface reduction rate of the roller die drawing is 25%, and the average surface reduction rate of the die drawing is 10%.

[0011] Furthermore, in step S5, the hot water washing temperature is above 80°C, and the high-pressure water washing pressure is 0.25 MPa.

[0012] Further, in step S6, the electroplating solution includes 20-250 g / L sulfuric acid and 30-350 g / L copper sulfate, and the electroplating temperature is 10-70°C.

[0013] Furthermore, in step S7, during neutralization, a sodium carbonate solution is selected for neutralization, and the pH value of the sodium carbonate solution is 8-10.

[0014] Furthermore, in step S8, the finishing speed is 8-12 m / min.

[0015] Furthermore, the method also includes sequentially paying out, layering and packaging the finished welding wire.

[0016] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art: The present invention designs the drawing process of high-strength steel welding wire, combines roller die drawing with die drawing, reduces the influence of work hardening on wire breakage, realizes non-annealing drawing below 70 kg, and simplifies the production process; simultaneously uses electric assisted copper plating to optimize the copper plating process, correspondingly improves production efficiency and reduces production costs.

[0017] Furthermore, in the present invention, the average reduction rate of roller die drawing is increased to 25%, and the average reduction rate of die drawing is reduced to 10%. In the pre-treatment of copper plating, the chemical treatment is changed to physical treatment, alkaline electrolysis and acid electrolysis are cancelled, and hot water and high-pressure water washing degreasing are replaced, and chemical copper plating is changed to electric-assisted copper plating to achieve green and efficient production. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Hereinafter, some specific embodiments of the present invention will be described in detail in an exemplary and non-limiting manner with reference to the accompanying drawings. The same reference numerals in the accompanying drawings indicate the same or similar components or parts. It should be understood by those skilled in the art that these drawings are not necessarily drawn to scale. In the accompanying drawings: Figure 1 The present invention is a process flow chart of a production process of a high-strength steel solid welding wire below 70 kg. DETAILED DESCRIPTION

[0019] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] The present invention provides a production process for a high-strength steel solid welding wire below 70 kg, see Figure 1 , including wire laying, mechanical shelling, abrasive belt dephosphorization, first drawing, copper plating pre-treatment, electric assisted copper plating, copper plating post-treatment, second drawing and wire taking-up.

[0021] The above process is further described below by way of examples.

[0022] Example 1 This embodiment provides a production process for high-strength steel solid welding wire below 70 kg, including the following steps: S1 Pay-off: A double-station hydraulic pay-off stand is used to pay-off the welding wire raw material; and the size of the welding wire raw material is Φ5.5mm; S2 Mechanical Shelling: The wire raw material after pay-off is sent to the mechanical shelling machine for mechanical shelling, which serves to pre-treat the oxide scale on the surface of the wire, peel off 70% to 80% of the oxide on the surface of the wire, and straighten the wire at the same time; S3 abrasive belt dephosphorization: the welding wire raw material after mechanical shelling is sent to the abrasive belt machine for mechanical abrasive belt dephosphorization to remove the oxide skin on the surface of the welding wire raw material; the mesh number of the abrasive belt is 60 mesh, and the abrasive belt speed is set at 2400r / min; S4 first drawing: the dephosphorized welding wire raw material is sequentially subjected to roller die drawing and die drawing, the roller die drawing speed is controlled at 15 m / min, and the die drawing speed is controlled at 8 m / min, thereby obtaining a welding wire semi-finished product; S5 Copper plating pretreatment: After the welding wire is drawn, it is first cleaned with hot water heated by steam (the water temperature is 80°C) to remove the grease lubricant on the surface of the welding wire (because a small amount of lubricant will be applied to the surface of the welding wire during the aforementioned drawing process); then it is cleaned with high-pressure water to remove the impurities remaining on the surface of the welding wire; S6 electric assisted copper plating: the plating solution in the copper plating tank is heated to 60°C by steam, wherein the plating solution includes 50g / L copper sulfate and 25g / L sulfuric acid solution, and the copper ions in the plating solution are reduced to metallic copper atoms through electrode reaction under the action of the external electric field, and metallic copper is deposited on the cathode, so that the copper element is attached to the surface of the welding wire; S7 copper plating post-treatment: first use water to remove a large amount of acidic impurities on the surface of the welding wire; then use a sodium carbonate solution with a pH of 10 to neutralize the acidity and impurity ions on the surface of the welding wire; finally, use water to wash the impurity ions on the surface of the welding wire, and use a dryer to heat to 200°C to dry the residual moisture on the surface of the welding wire; and the washing water generated in this process is recycled to the front-end water washing process for recycling; S8 Second drawing: The copper-plated semi-finished welding wire is finely drawn, and the fine drawing speed is controlled at 10 m / min to obtain a high-strength steel solid welding wire product; S9 wire taking-up: The finished welding wire is taken up by a wire taking-up machine.

[0023] Comparative Example 1 The present embodiment provides an original production process of high-strength steel solid welding wire below 70 kg, including mechanical shelling, primary water washing, chemical descaling, secondary water washing, surface coating (boration), drying, rough drawing, fine drawing, tertiary water washing, chemical copper plating, fine drawing, wire taking-up, layer winding and packaging steps in sequence.

[0024] Among them, mechanical shelling, primary water washing, secondary water washing, tertiary water washing, drying, rough drawing, fine drawing, precision drawing, wire winding, layer winding and packaging processes are all conventional technologies and will not be described in detail here. In addition, the primary water washing is to remove the oxide scale on the surface of the welding wire raw material; the secondary water washing is to remove the acid and other impurities remaining on the surface of the welding wire raw material after chemical descaling; the tertiary water washing is to remove the oxide scale on the surface of the welding wire after fine drawing. The corresponding drawing processes all directly use molds to draw the welding wire.

[0025] For the above chemical descaling process, the sulfuric acid concentration is controlled at 150±20g / L and the electrolysis current is maintained at above 500A to remove the oxide scale on the surface of the welding wire; For the above-mentioned surface coating borax process, borax is used for boronization, and the boronization temperature is guaranteed to be above 80 degrees; The chemical copper plating process includes the following steps: alkaline washing → air blowing → neutralization washing → air blowing → acid washing → air blowing → activation → air blowing → cold water washing → air blowing → copper plating → air blowing → cold water washing → neutralization washing → cold water washing → hot water washing → high pressure air blowing → drying.

[0026] Specifically, during alkaline washing, the solution temperature is maintained above 100°C; the electrolysis current is maintained between 1000A and 1500A; and the solution concentration is controlled at 300-400g / L. During acid washing, the electrolysis current is maintained between 1000A and 1500A; and the solution concentration is maintained at 500-650 g / L. During activation acid washing, the solution concentration is controlled at 300-400 g / L.

[0027] When copper plating, the solution temperature is kept above 40℃; the solution concentration is kept at 200~400 g / L; the sulfuric acid concentration in the solution is kept at 150~250 g / L. When neutralizing and washing, the solution pH value is kept at 13~15. The hot water washing temperature is kept above 80 degrees and the pH value is kept at 9~11. When high-pressure air blowing, the air blowing pressure must be kept above 0.6Mpa.

[0028] The present invention conducted performance tests on the above-mentioned Example 1 and Comparative Example 1, and the specific test results are as follows: Tensile strength / MPa Yield strength / MPa Elongation after break / % Sectional shrinkage / % Example 1 780 569 24.5 73 Comparative Example 1 764 558 24 69 In summary, the present invention discloses a production process for high-strength steel solid welding wire below 70 kg. In the rough drawing process, roller die drawing combined with die drawing is used to reduce the influence of work hardening on wire breakage, while realizing non-annealing drawing below 70 kg, simplifying the production process. Electrically assisted copper plating is used simultaneously to optimize the copper plating process, thereby correspondingly improving production efficiency and reducing production costs.

[0029] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with this technology to understand the contents of the present invention and implement them accordingly. They cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A production process for high-strength steel solid welding wire below 70 kg, characterized in that: The steps include: S1 Pay-off: Use double-station hydraulic pay-off stand to pay-off the welding wire raw materials; S2 Mechanical Shelling: Send the welding wire raw material after wire laying into a mechanical shelling machine for mechanical shelling, pretreat the oxide scale on the surface of the welding wire, and straighten the welding wire raw material synchronously; S3 abrasive belt dephosphorization: sending the welding wire raw material after mechanical shelling into the abrasive belt machine for dephosphorization to remove the oxide scale on the surface of the welding wire raw material; S4 first drawing: roller die drawing and die drawing are performed on the dephosphorized welding wire raw material in sequence to obtain a welding wire semi-finished product; S5 copper plating pretreatment: washing the semi-finished welding wire after the first drawing with hot water and high-pressure water in sequence; S6: electro-assisted copper plating: electro-assisted copper plating is performed on the semi-finished welding wire after the copper plating pre-treatment; S7 copper plating post-treatment: washing, neutralizing and secondary washing the welding wire semi-finished product after the electric assisted copper plating in sequence to remove residual acid and impurities on the surface of the welding wire semi-finished product; S8 second drawing: fine drawing the semi-finished welding wire after copper plating treatment to obtain the high-strength steel solid welding wire; S9: feeding the high-strength steel solid welding wire into a double-reel wire take-up machine for wire take-up.

2. The process for producing high-strength steel solid welding wire below 70 kg according to claim 1, characterized in that: The chemical composition of the applicable high-strength steel solid welding wire below 70 kg is as follows by weight percentage: C≤0.11%, Mn: 1.4~1.8%, Si: 0.5~1%, P≤0.025%, S≤0.025%, Cr: 0.1~0.6%; Ni≤0.4%, Mo≤0.25%; Ti: ≤0.12%, the balance is Fe and unavoidable impurities.

3. The production process of a high-strength steel solid welding wire below 70 kg according to claim 1, characterized in that: In step S3, the mesh number of the sanding belt is 60 meshes, and the rotation speed of the sanding belt is 1200-2400 r / min.

4. The process for producing high-strength steel solid welding wire below 70 kg according to claim 1, characterized in that: In step S4, the roller die pulling speed is 12-15 m / min; the die pulling speed is 6-8 m / min.

5. The production process of a high-strength steel solid welding wire below 70 kg according to claim 1, characterized in that: In step S4, the average reduction ratio of the roller die drawing is 25%, and the average reduction ratio of the die drawing is 10%.

6. The process for producing high-strength steel solid welding wire below 70 kg according to claim 5, characterized in that: In step S5, the hot water washing temperature is above 80°C, and the high-pressure water washing pressure is 0.25 MPa.

7. The process for producing high-strength steel solid welding wire below 70 kg according to claim 1, characterized in that: In step S6, the electroplating solution includes 20-250 g / L sulfuric acid and 30-350 g / L copper sulfate, and the electroplating temperature is 10-70°C.

8. The process for producing high-strength steel solid welding wire below 70 kg according to claim 1, characterized in that: In step S7, during the neutralization, a sodium carbonate solution is selected for neutralization, and the pH value of the sodium carbonate solution is 8-10.

9. The process for producing high-strength steel solid welding wire below 70 kg according to claim 1, characterized in that: In step S8, the finishing speed is 8-12 m / min.

10. The process for producing high-strength steel solid welding wire below 70 kg according to claim 1, characterized in that: The method also includes sequentially paying out, layer winding and packaging the finished welding wire product.

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