Vacuum-pumping seamless flux-cored wire and filling process thereof

Abstract

The invention provides a vacuumizing seamless flux-cored wire and a filling process thereof, the vacuumizing seamless flux-cored wire comprises a seamless welding wire skin and a welding wire flux core, and the seamless welding wire skin is of an integrally formed hollow structure with the two ends open; the hollow part of the seamless welding wire skin is filled with the welding wire flux core in a vacuumizing mode; the welding wire flux core comprises, by weight, 30-35 parts of rutile, 12-16 parts of ferrosilicon powder, 4-6 parts of nickel powder, 5-8 parts of manganese-iron alloy, 2-4 parts of chromium powder, 3-6 parts of dolomite, 2-3 parts of fluorite, 0.5-1 part of niobium powder and 1-2 parts of titanium-boron alloy. The seamless welding wire outer skin can effectively block outside air and moisture, so that the welding wire flux core is not prone to being affected with damp, it is guaranteed that the flux-cored wire is reliably used and stored for a long time in various environments, the consistency and reliability of the welding quality are effectively improved, and the production cost and the maintenance difficulty are reduced.

Description

Technical Field

[0001] The invention relates to the technical field of welding materials, in particular to a vacuum seamless flux-cored welding wire and a filling process thereof. Background Art

[0002] With the continuous development of modern industry, the requirements for welding quality and efficiency are getting higher and higher. In many fields, such as aerospace, automobile manufacturing, shipbuilding, building structures, etc., welded structures need to have higher strength, better toughness and corrosion resistance to meet the requirements of use in complex working conditions and harsh environments. Traditional flux-cored welding wires are usually made by wrapping powder with steel strips, that is, the prepared steel strips are first passed through a forming device to form a U-shaped groove, and then a special filling device is used to fill the prepared powder into the U-shaped steel strip. After the powder is filled, the opening of the U-shaped steel strip is closed by another set of rollers, so that the powder is completely wrapped inside the steel strip. However, this production method still has the following defects: First, after the powder is filled, the opening of the U-shaped steel strip is closed by another set of rollers. The combination between the steel strip and the powder is not completely tight, and there are certain gaps and pores, which makes the welding wire susceptible to external environmental influences such as moisture and oxygen during storage and transportation, causing changes in the chemical composition of the flux core, thereby affecting the welding quality. Second, the powder filling process cannot ensure uniform filling, which will lead to unstable arc during welding and poor weld formation. In addition, the production process of traditional flux-cored welding wire is relatively complex and costly, and more welding smoke and spatter may be generated during the welding process, which has a certain impact on the environment and the health of operators. Summary of the invention

[0003] The purpose of the present invention is to provide a vacuum seamless flux-cored welding wire and a filling process thereof, which effectively solves the technical problems that the flux core of the traditional welding wire is easily affected by moisture and has uneven composition.

[0004] To solve the above technical problems, the present invention provides a first aspect, which provides a vacuum seamless flux-cored welding wire, including a seamless welding wire sheath and a welding wire core, wherein the seamless welding wire sheath is a hollow structure with openings at both ends and formed in one piece; the welding wire core is filled in the hollow part of the seamless welding wire sheath by vacuuming; the welding wire core includes the following components and the weight proportions of each component are respectively: 30-35 parts of rutile, 12-16 parts of ferrosilicon powder, 4-6 parts of nickel powder, 5-8 parts of ferromanganese alloy, 2-4 parts of chromium powder, 3-6 parts of dolomite, 2-3 parts of fluorite, 0.5-1 part of niobium powder, and 1-2 parts of titanium-boron alloy.

[0005] Preferably, the particle size of the welding wire core is 60-200 mesh.

[0006] Preferably, the outer sheath of the seamless welding wire is made of any one or more materials selected from the group consisting of copper, silver and nickel.

[0007] In a second aspect, the present invention further provides a filling process for the vacuum seamless flux-cored welding wire as described in the first aspect, comprising the following steps: Mixing raw materials of various components of welding wire core with liquid additives to obtain mud-like core blanks; Taking the mud-like core blank material and heating and melting it to obtain a molten core; Take the seamless welding wire outer skin prepared in advance, and connect the vacuum equipment to one end of the seamless welding wire outer skin for vacuum treatment; Pour the molten flux core into the hollow part of the seamless welding wire outer skin, while keeping the vacuum equipment running until the molten flux core fills the hollow part of the seamless welding wire outer skin to obtain welding wire blank; The welding wire blank is placed in a vacuum environment for cooling treatment, so that the molten core is solidified inside the hollow welding wire to obtain a vacuum seamless cored welding wire.

[0008] Preferably, the raw materials of each component of the welding wire core are mixed with the liquid additive to obtain a mud-like core blank, which specifically includes the following sub-steps: The raw materials of the welding wire core components are mixed with an appropriate amount of water in the following proportions: 30-35 parts of rutile, 12-16 parts of ferrosilicon powder, 4-6 parts of nickel powder, 5-8 parts of ferromanganese alloy, 2-4 parts of chromium powder, 3-6 parts of dolomite, 2-3 parts of fluorite, 0.5-1 part of niobium powder, and 1-2 parts of titanium-boron alloy, and placed in a vacuum stirring device for stirring until it becomes muddy to obtain a bubble-free muddy core blank.

[0009] Preferably, the raw materials of each component of the welding wire core are mixed with the liquid additive to obtain a mud-like core blank, which specifically includes the following sub-steps: The weighed raw materials of each component of the welding wire core are placed in a vacuum stirring device, and stirred at a stirring speed of 50-100 rpm for 3-5 min to obtain a preliminarily uniform mixed raw material; Take 20% to 30% of the total mass of the mixed raw materials and slowly add water to the mixed raw materials. Stir at the same time during the water addition process. Continue stirring for 2 to 3 minutes after the water is added, and stir at a stirring speed of 150 to 200 rpm for 10 to 15 minutes to obtain a uniformly mixed and bubble-free muddy core blank.

[0010] Preferably, the pre-prepared seamless welding wire sheath specifically comprises the following sub-steps: One or more materials of copper, silver and nickel prepared in advance are melted and cast to obtain a rod-shaped blank; Placing the rod-shaped blank in a heating furnace for preheating, and performing a perforation process on the preheated rod-shaped blank to obtain a first welding wire outer skin blank having a hollow structure; The first welding wire sheath blank is subjected to a first drawing and reducing process to obtain a second welding wire sheath blank; Annealing the second welding wire sheath blank to obtain a third welding wire sheath blank; The third welding wire sheath blank is subjected to a second drawing and diameter reduction to obtain a fourth welding wire sheath blank; The fourth welding wire sheath blank is cleaned and polished to obtain a seamless welding wire sheath.

[0011] Preferably, after one or more of the pre-prepared copper, silver and nickel materials are melted and cast, they are cooled and turned to obtain a rod-shaped outer skin blank without oxide scale.

[0012] Preferably, in the step of taking the rod-shaped outer skin blank and placing it in a heating furnace for preheating, the temperature is raised to 500-700° C. at a heating rate of 5-10° C. / min and kept warm for 15-30 minutes.

[0013] Preferably, the second welding wire outer sheath blank is subjected to annealing treatment, which specifically includes the following sub-steps: After cleaning the second welding wire sheath blank, the temperature in the annealing furnace is increased to 400-700°C at a heating rate of 5-10°C / min, and after being kept warm for 1-3 hours, the blank is cooled to room temperature along with the furnace to obtain the third welding wire sheath blank.

[0014] Compared with the prior art, the technical solution provided by the present invention has the following advantages: The vacuum seamless flux-cored welding wire provided by the present invention has a hollow structure formed in one piece because the seamless welding wire outer skin is an integrally formed structure, and the welding wire flux core is filled in the seamless welding wire outer skin by vacuuming. The seamless welding wire outer skin can effectively block the air and moisture outside, so that the welding wire flux core is not easy to be affected by moisture, and the vacuum seamless flux-cored welding wire is ensured to be used reliably and stored for a long time in various environments, and the consistency and reliability of welding quality are effectively improved, and the production cost and maintenance difficulty are reduced. The technical problems such as the traditional welding wire flux core being susceptible to moisture and the uneven composition are effectively solved, and the quality and stability of the weld are greatly improved. At the same time, by using the raw materials of the above components in the welding wire flux core material, the vacuum seamless flux-cored welding wire can play a good metallurgical role in the welding process, such as rutile helps to stabilize the arc and slag, ferrosilicon powder can be deoxidized, and nickel powder, ferromanganese alloy, chromium powder, etc. can improve the strength, toughness and corrosion resistance of the weld. The vacuum seamless flux-cored welding wire has stable arc, less spatter, and easy slag removal during welding, which greatly improves the efficiency and quality of welding. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the prior art and the embodiments of the present application, the drawings required for use in the description of the prior art and the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 The present invention is a filling process flow chart of a vacuum seamless flux-cored welding wire in an embodiment of the present invention.

[0017] Figure 2 The present invention is a flow chart of the preparation of the seamless welding wire sheath in an embodiment of the present invention. DETAILED DESCRIPTION

[0018] In order to better understand the purpose, structure and function of the present invention, the following is a further detailed description of a vacuum seamless flux-cored welding wire and its filling process provided by the present invention in conjunction with the accompanying drawings, so that technicians in the field can better understand the present invention and implement it, but the examples given are not intended to limit the present invention.

[0019] The present invention provides a vacuum seamless flux-cored welding wire, comprising a seamless welding wire outer skin and a welding wire flux core, wherein the seamless welding wire outer skin is a hollow structure with two ends opened and integrally formed; the welding wire flux core is filled in the hollow part of the seamless welding wire outer skin by vacuuming; the welding wire flux core comprises the following components and the weight proportions of each component are respectively: 30-35 parts of rutile, 12-16 parts of ferrosilicon powder, 4-6 parts of nickel powder, 5-8 parts of ferromanganese alloy, 2-4 parts of chromium powder, 3-6 parts of dolomite, 2-3 parts of fluorite, 0.5-1 parts of niobium powder, and 1-2 parts of titanium-boron alloy. Among them, the particle size of the welding wire flux core is 60-200 meshes. The seamless welding wire outer skin is made of any one or more materials of copper, silver, and nickel.

[0020] The functions of each component in the welding wire core are as follows: Rutile: slag protection weld, arc stabilization, and spatter reduction. During the welding process, rutile can form slag, cover the surface of the weld, and play a role in protecting the weld. Slag can prevent harmful gases such as oxygen and nitrogen in the air from reacting with molten metal, reducing the oxidation and nitridation of weld metal. At the same time, slag can also improve the forming of the weld and make the weld surface smoother. If its content is too low, it may not be able to completely cover the weld, resulting in gas intrusion; if the content is too high, there may be too much slag, affecting the welding operation and the appearance quality of the weld. The weight proportion of rutile in the welding wire core of the present invention is 30 to 35 parts. For example, the weight proportion of rutile in the welding wire core can be any value within the range of 30 to 35 parts, such as 30 parts, 32.5 parts, 35 parts, etc., which can ensure that enough slag is formed to effectively protect the weld while avoiding excessive slag affecting the welding operation and the appearance of the weld. At the same time, the coverage and fluidity of the slag can achieve a good balance, which is conducive to improving the quality of the weld.

[0021] Ferrosilicon powder: as a deoxidizer. During the welding process, ferrosilicon can react with oxygen in the weld to remove oxygen from the weld metal, thereby improving the quality of the weld. At the same time, silicon can be dissolved in the weld metal, play a role in solid solution strengthening, and improve the strength of the weld metal. If its content is too little, the deoxidation effect is not obvious; if the content is too much, it may cause the silicon content in the weld metal to be too high, making the weld metal brittle. The weight proportion of ferrosilicon powder in the welding wire core of the present invention is 12 to 16 parts. For example, the weight proportion of ferrosilicon powder in the welding wire core can be any value within the range of 12 to 16 parts, such as 12 parts, 14 parts, 16 parts, etc., which can effectively perform the deoxidation operation while providing an appropriate amount of silicon to strengthen the weld, which can ensure that the oxygen content in the weld metal is controlled at a low level, and the weld will not become brittle due to excessive silicon content, which helps to maintain good mechanical properties of the weld.

[0022] Nickel powder: used to improve the toughness and crack resistance of weld metal. Nickel can refine the grains of weld metal, improve the organizational structure of weld metal, and better resist the generation and expansion of cracks when subjected to external forces. If its content is too little, the improvement effect on toughness and crack resistance is not obvious; too much content may increase costs and may have an adverse effect on other properties. The weight proportion of nickel powder in the welding wire core of the present invention is 4 to 6 parts. For example, the weight proportion of nickel powder in the welding wire core can be any value within the range of 4 to 6 parts, such as 4 parts, 5 parts, 6 parts, etc., which can effectively play the role of refining grains and improving toughness. It can effectively improve the organizational structure of weld metal, making it more crack-resistant when subjected to external forces, and will not increase excessive costs or have an adverse effect on other properties due to excessive nickel content.

[0023] Manganese iron alloy: as a deoxidizer and alloying agent. As a deoxidizer, manganese iron alloy can react with oxygen in the weld to reduce the oxygen content in the weld metal. As an alloying agent, manganese can improve the strength and toughness of the weld metal. Manganese can form a solid solution with iron, strengthen the matrix of the weld metal, and improve the processing properties of the weld metal. If its content is too low, the deoxidation and strengthening effects are insufficient; if the content is too high, the manganese content of the weld metal may be too high, affecting other properties of the weld metal, such as corrosion resistance. The weight proportion of manganese iron alloy in the welding wire core of the present invention is 5 to 8 parts. For example, the weight proportion of manganese iron alloy in the welding wire core can be any value within the range of 5 to 8 parts, such as 5 parts, 6.5 parts, 8 parts, etc., which can more effectively improve the strength and toughness of the weld metal while ensuring a good deoxidation effect, and can better play the role of manganese and iron in forming a solid solution to strengthen the matrix, while not making the manganese content of the weld metal too high to affect other properties, such as corrosion resistance.

[0024] Chromium powder: used to improve the corrosion resistance of weld metal. Chromium can form a dense oxide film on the surface of weld metal, preventing external corrosive media from contacting weld metal, thereby improving the corrosion resistance of weld metal. At the same time, chromium can also improve the strength and hardness of weld metal. If its content is too low, the corrosion resistance and strengthening effects are not obvious; too high a content may increase the brittleness of weld metal. The weight proportion of chromium powder in the welding wire core of the present invention is 2 to 4 parts. For example, the weight proportion of chromium powder in the welding wire core can be any value within the range of 2 to 4 parts, such as 2 parts, 3 parts, 4 parts, etc., which can form an effective dense oxide film on the surface of weld metal, improve the corrosion resistance of weld metal, and moderately improve the strength and hardness of weld metal. While ensuring corrosion resistance and strengthening effects, it can avoid increasing the brittleness of weld metal due to excessive chromium content.

[0025] Dolomite: plays the role of slag formation and arc stabilization. Dolomite can improve the performance of slag, making it easier for the slag to cover the surface of the weld, and can adjust the stability of the welding arc, making the welding process smoother. If its content is too little, the improvement effect on the slag performance and arc stability is not good; too much content may affect other properties of the slag, such as fluidity. The weight proportion of dolomite in the welding wire core of the present invention is 3 to 6 parts. For example, the weight proportion of dolomite in the welding wire core can be any value within the range of 3 to 6 parts, such as 3 parts, 4.5 parts, 6 parts, etc., which can effectively play the dual role of slag formation and arc stabilization, can well improve the slag performance, make it easier to cover the weld surface, and can better adjust the stability of the welding arc, making the welding process smoother.

[0026] Fluorite: As a flux, it can reduce the melting point and viscosity of the slag. During the welding process, fluorite can make the slag flow more easily and cover the weld surface. It also helps to separate the weld metal from the slag and improve the quality of the weld. If its content is too little, the fluxing effect is not obvious; too much content may cause the slag to be too thin, affecting the protective effect of the slag on the weld. The weight proportion of fluorite in the welding wire core of the present invention is 2 to 3 parts. For example, the weight proportion of fluorite in the welding wire core can be any value within the range of 2 to 3 parts, such as 2 parts, 2.5 parts, 3 parts, etc., which can effectively reduce the melting point and viscosity of the slag, so that it can play a good fluxing role, and can make the slag flow more easily and cover the weld. It also helps to separate the weld metal from the slag and ensure the quality of the weld.

[0027] Niobium powder: plays a role in refining the grains. During the solidification process of the weld metal, niobium can prevent the growth of grains, making the grains of the weld metal finer, thereby improving the strength and toughness of the weld metal. If its content is too little, the effect on grain refinement is not obvious; too much content may cause the balance of other elements to be destroyed, affecting the performance of the weld metal. The weight proportion of niobium powder in the welding wire core of the present invention is 0.5 to 1 part. For example, the weight proportion of niobium powder in the welding wire core can be any value within the range of 0.5 to 1 part, such as 0.5 part, 0.75 part, 1 part, etc., which can effectively refine the grains of the weld metal, improve the strength and toughness of the weld metal, and can better play the role of niobium in preventing grain growth without destroying the balance of other elements.

[0028] Titanium-boron alloy: as a grain refiner. Titanium and boron can act as heterogeneous nuclei during the solidification process of the weld metal to promote grain refinement. At the same time, titanium can also react with harmful elements such as nitrogen in the weld to reduce its impact on the quality of the weld. Boron can improve the hardenability of the weld metal and improve the performance of the weld metal to a certain extent. If its content is too low, the effect of refining grains and purifying the weld is not good; if the content is too high, the titanium and boron content in the weld metal may be too high, which will have an adverse effect on other properties of the weld metal. The weight proportion of the titanium-boron alloy in the welding wire core of the present invention is 1 to 2 parts. For example, the weight proportion of the titanium-boron alloy in the welding wire core can be any value within the range of 1 to 2 parts, such as 1 part, 1.5 parts, 2 parts, etc., which can give full play to the role of grain refinement and removal of harmful elements, and can better utilize titanium and boron as heterogeneous nuclei to promote grain refinement, as well as the characteristics of titanium reacting with harmful elements, while avoiding the adverse effects of excessive titanium and boron content in the weld metal on other properties.

[0029] The vacuum seamless flux-cored welding wire provided by the present invention has a hollow structure formed in one piece because the seamless welding wire outer skin is an integrally formed structure, and the welding wire flux core is filled in the seamless welding wire outer skin by vacuuming. The seamless welding wire outer skin can effectively block the air and moisture outside, so that the welding wire flux core is not easy to be affected by moisture, and the vacuum seamless flux-cored welding wire is ensured to be used reliably and stored for a long time in various environments, and the consistency and reliability of welding quality are effectively improved, and the production cost and maintenance difficulty are reduced. The technical problems such as the traditional welding wire flux core being susceptible to moisture and the uneven composition are effectively solved, and the quality and stability of the weld are greatly improved. At the same time, by using the raw materials of the above components in the welding wire flux core material, the vacuum seamless flux-cored welding wire can play a good metallurgical role in the welding process, such as rutile helps to stabilize the arc and slag, ferrosilicon powder can be deoxidized, and nickel powder, ferromanganese alloy, chromium powder, etc. can improve the strength, toughness and corrosion resistance of the weld. The vacuum seamless flux-cored welding wire has stable arc, less spatter, and easy slag removal during welding, which greatly improves the efficiency and quality of welding.

[0030] See also Figure 1 As shown, the present invention provides a filling process for a vacuum seamless flux-cored welding wire, comprising the following steps: Step S1, mixing the raw materials of each component of the welding wire core with the liquid additive to obtain a mud-like core blank. Specifically comprising the following sub-steps: The raw materials of the welding wire core components are mixed with an appropriate amount of water according to the ratio of 30-35 parts of rutile, 12-16 parts of ferrosilicon powder, 4-6 parts of nickel powder, 5-8 parts of ferromanganese alloy, 2-4 parts of chromium powder, 3-6 parts of dolomite, 2-3 parts of fluorite, 0.5-1 parts of niobium powder, and 1-2 parts of titanium boron alloy, and placed in a vacuum stirring device for stirring until muddy, to obtain a bubble-free muddy core blank. Further, the following sub-steps are specifically included: The weighed raw materials of each component of the welding wire core are placed in a vacuum stirring device, and stirred at a stirring speed of 50-100 rpm for 3-5 min to obtain a preliminarily uniform mixed raw material; Take 20% to 30% of the total mass of the mixed raw materials and slowly add water to the mixed raw materials. Stir at the same time during the water addition process. Continue stirring for 2 to 3 minutes after the water is added, and stir at a stirring speed of 150 to 200 rpm for 10 to 15 minutes to obtain a uniformly mixed and bubble-free muddy core blank.

[0031] Specifically, in this step, the raw materials of each component of the welding wire core are mixed with an appropriate amount of water and stirred into a mud state under a vacuum environment. This not only allows the various raw materials to fully contact and achieve uniform mixing, but also removes bubbles generated during the stirring process. When the mud-like core blank is heated and melted in step S2, it is used to prevent bubbles from agglomerating or bursting, resulting in an uneven internal structure of the molten core.

[0032] Step S2: taking the mud-like core blank and heating and melting it to obtain a molten core.

[0033] Specifically, this step heats the muddy flux core blank to a molten state, which not only facilitates the subsequent pouring of the flux core into the hollow part of the seamless welding wire sheath, but also the flux core in a molten state can better fill the hollow part of the seamless welding wire sheath, and can be tightly combined with the seamless welding wire sheath after solidification to form an integral structure, thereby providing a stable flux core for subsequent welding work.

[0034] Step S3, taking the pre-prepared seamless welding wire outer skin, and connecting a vacuum device to one end of the seamless welding wire outer skin for vacuum treatment.

[0035] Specifically, this step can create an oxygen-free environment for the subsequent injection of the molten core by vacuuming, ensuring that the molten core fills the seamless welding wire sheath in a pure environment, thereby improving the quality of the vacuum seamless welding wire. Figure 2 As shown, the pre-prepared seamless welding wire sheath specifically includes the following sub-steps: Step S31: melt and cast one or more of the pre-prepared copper, silver and nickel materials to obtain a rod-shaped blank.

[0036] Specifically, in this step, one or more of the pre-prepared copper, silver, and nickel materials are melted and casted, and these metal raw materials can be preliminarily formed into a required shape (rod shape), providing basic materials for the subsequent production of seamless welding wire outer skin. After the pre-prepared one or more of the copper, silver, and nickel materials are melted and cast, they are cooled and turned to obtain a rod-shaped outer skin blank without oxide scale.

[0037] Step S32, placing the rod-shaped blank in a heating furnace for preheating, and performing a perforation process on the preheated rod-shaped blank to obtain a first welding wire sheath blank with a hollow structure.

[0038] Specifically, this step preheats the rod-shaped stock in a heating furnace so that the rod-shaped stock reaches a suitable temperature for easy perforation. At a suitable temperature, the ductility of the metal is better, which can reduce the deformation resistance during the perforation process, reduce the energy consumption during the processing process, and also reduce the stress concentration inside the material. The perforation process is to form a hollow structure inside the rod-shaped stock, thereby obtaining a first welding wire sheath stock with a hollow structure, providing a basis for subsequent filling of the welding wire core, so that the seamless welding wire sheath can accommodate the welding wire core.

[0039] Step S33, subjecting the first welding wire sheath blank to a first drawing and diameter reduction process to obtain a second welding wire sheath blank.

[0040] Specifically, this step is used to refine the size of the first welding wire sheath blank by performing the first drawing and reducing the diameter of the first welding wire sheath blank. During the drawing process, a tensile force is applied to the first welding wire sheath blank through a die to reduce its diameter. The dimensional accuracy of the first welding wire sheath can be improved, the diameter of the first welding wire sheath can be made more uniform, and the surface quality of the first welding wire sheath can be improved, and its mechanical properties can be enhanced, such as improving its strength and hardness, to provide a better performance basis for subsequent processing and use.

[0041] Step S34, annealing the second welding wire sheath blank to obtain a third welding wire sheath blank.

[0042] Specifically, this step is to eliminate the internal stress generated during the first drawing and reducing process by annealing the second welding wire sheath blank. During the drawing process, the first welding wire sheath blank will undergo work hardening due to external force, and a large amount of stress will accumulate inside. These stresses will make the material brittle and reduce its toughness and ductility. Through annealing, the crystal structure inside the material is restored and adjusted, the internal stress is eliminated, and the toughness and ductility of the second welding wire sheath blank are restored to facilitate subsequent processing steps. Among them, in the step of taking the rod-shaped sheath blank and placing it in a heating furnace for preheating, the temperature is raised to 500~700℃ at a heating rate of 5~10℃ / min, and kept warm for 15~30min.

[0043] Step S35, drawing and reducing the diameter of the third welding wire sheath blank for the second time to obtain a fourth welding wire sheath blank.

[0044] Specifically, this step is used to further refine the size of the third welding wire sheath stock by performing a second drawing and reducing the diameter of the third welding wire sheath stock, thereby improving the dimensional accuracy and surface quality of the third welding wire sheath stock. The third welding wire sheath stock obtained after annealing has better processing performance, and the size of the third welding wire sheath stock can be adjusted to a size specification closer to that required by the final seamless welding wire sheath through the second drawing, and the mechanical properties of the final seamless welding wire sheath can also be further enhanced.

[0045] Step S36, cleaning and polishing the fourth welding wire sheath blank to obtain a seamless welding wire sheath.

[0046] Specifically, this step is used to remove impurities, oil stains and oxide layers attached to the surface of the fourth welding wire sheath stock during processing by cleaning and polishing the fourth welding wire sheath stock. Chemical solvents or physical flushing methods can be used for cleaning to ensure the cleanliness of the outer skin surface. Polishing is used to make the surface of the fourth welding wire sheath stock smoother, improve its surface quality, and reduce surface roughness, so that the obtained seamless welding wire sheath is more beautiful in appearance, and can better play its function in the subsequent combination with the welding wire core and welding process, for example, it can reduce the friction between the welding wire core and the seamless welding wire sheath, so that the core filling is smoother, and it can also reduce the spatter and other problems caused by the rough surface during welding.

[0047] Step S4, pouring the molten flux core into the hollow part of the seamless welding wire outer skin, while keeping the vacuum equipment running, until the molten flux core fills the hollow part of the seamless welding wire outer skin to obtain a welding wire blank.

[0048] Specifically, this step is to allow the flux core to fully fill the outer skin of the seamless welding wire in an oxygen-free environment by pouring the molten flux core into the hollow part of the outer skin of the seamless welding wire and keeping the vacuum equipment running. Under the vacuum state, the molten flux core can flow smoothly into the hollow part to avoid air mixing. At the same time, the continuous vacuum environment can ensure that the molten flux core is not oxidized during the filling process, and can evenly fill the entire hollow part, so that the molten flux core is more evenly distributed inside the outer skin of the seamless welding wire, thereby making the molten flux core and the outer skin of the seamless welding wire more closely bonded, providing a good foundation for subsequent welding work and ensuring the stability of the weld quality.

[0049] Step S5, placing the welding wire blank in a vacuum environment for cooling treatment, so that the molten core solidifies inside the hollow welding wire, and obtains a vacuumized seamless cored welding wire.

[0050] Specifically, this step places the welding wire blank in a vacuum environment for cooling, firstly to ensure that the molten core will not be oxidized due to contact with air during the solidification process. Secondly, cooling in a vacuum environment can prevent the formation of bubbles during the solidification process of the molten core. Because there is no interference from external air in a vacuum environment, the molten core can smoothly transform from liquid to solid, making the structure of the molten core denser after solidification, and the fit with the seamless welding wire skin is also closer. The finally obtained vacuum seamless flux-cored welding wire is of higher quality and can better play its role in the welding process, thereby improving the quality of the weld.

[0051] The present invention is described in detail below through some specific examples. The drugs used in the following examples can all be obtained through common commercial means.

[0052] Example 1 The vacuumized seamless flux-cored welding wire of this embodiment includes a seamless welding wire outer skin and a welding wire flux core. The seamless welding wire outer skin is a hollow structure with openings at both ends and is integrally formed. The welding wire flux core is filled in the hollow part of the seamless welding wire outer skin by vacuuming. The welding wire flux core includes the following components and the weight proportions of each component are respectively: 30 parts of rutile, 12 parts of ferrosilicon powder, 4 parts of nickel powder, 5 parts of ferromanganese alloy, 2 parts of chromium powder, 3 parts of dolomite, 2 parts of fluorite, 0.5 parts of niobium powder, and 1 part of titanium-boron alloy.

[0053] Step 1: Place the weighed raw materials of each component of the welding wire core in a vacuum stirring device, stir at a stirring speed of 50 rpm for 3 minutes to obtain a preliminarily uniform mixed raw material.

[0054] Step 2: In a vacuum stirring device, mix the mixed raw materials with water in a ratio of 20% of the total weight of the welding wire core, stir while adding water, continue stirring for 2 minutes after the water is added, and then stir at a stirring speed of 150 rpm for 10 minutes to obtain a uniformly mixed and bubble-free mud core blank.

[0055] Step 3: first heat and melt the mud-like flux core blank to obtain a molten flux core, and then pour the molten flux core into the hollow part of the seamless welding wire outer skin, while keeping the vacuum equipment running until the molten flux core fills the hollow part of the seamless welding wire outer skin to obtain the welding wire blank.

[0056] Step 4: Place the welding wire blank in a vacuum environment for cooling treatment, so that the molten core solidifies in the outer skin of the hollow welding wire to obtain a vacuum seamless flux-cored welding wire.

[0057] Example 2 The vacuum seamless flux-cored welding wire of this embodiment includes a seamless welding wire outer skin and a welding wire flux core. The seamless welding wire outer skin is a hollow structure with openings at both ends and is integrally formed; the welding wire flux core is filled in the hollow part of the seamless welding wire outer skin by vacuum extraction; the welding wire flux core includes the following components and the weight proportions of each component are respectively: 32 parts of rutile, 14 parts of ferrosilicon powder, 5 parts of nickel powder, 6 parts of manganese iron alloy, 3 parts of chromium powder, 4 parts of dolomite, 2.5 parts of fluorite, 0.8 parts of niobium powder, and 1.5 parts of titanium-boron alloy.

[0058] Step 1: Place the weighed raw materials of each component of the welding wire core in a vacuum stirring device, stir at a stirring speed of 75 rpm for 4 minutes to obtain a preliminarily uniform mixed raw material.

[0059] Step 2: In a vacuum stirring device, mix the mixed raw materials with water in a ratio of 25% of the total weight of the welding wire core, stir while adding water, continue stirring for 2.5 minutes after the water is added, and then stir at a stirring speed of 175 rpm for 12.5 minutes to obtain a uniformly mixed and bubble-free mud core blank.

[0060] Step 3: first heat and melt the mud-like flux core blank to obtain a molten flux core, and then pour the molten flux core into the hollow part of the seamless welding wire outer skin, while keeping the vacuum equipment running until the molten flux core fills the hollow part of the seamless welding wire outer skin to obtain the welding wire blank.

[0061] Step 4: Place the welding wire blank in a vacuum environment for cooling treatment, so that the molten core solidifies in the outer skin of the hollow welding wire to obtain a vacuum seamless flux-cored welding wire.

[0062] Example 3 The vacuumized seamless flux-cored welding wire of this embodiment comprises a seamless welding wire sheath and a welding wire core, wherein the seamless welding wire sheath is a hollow structure with openings at both ends and formed in one piece; the welding wire core is filled in the hollow part of the seamless welding wire sheath by vacuuming; the welding wire core comprises the following components and the weight proportions of each component are respectively: 33 parts of rutile, 15 parts of ferrosilicon powder, 5.5 parts of nickel powder, 7 parts of ferromanganese alloy, 3.5 parts of chromium powder, 5 parts of dolomite, 2.8 parts of fluorite, 0.9 parts of niobium powder, and 1.8 parts of titanium-boron alloy.

[0063] Step 1: Place the weighed raw materials of each component of the welding wire core in a vacuum stirring device, stir at a stirring speed of 75 rpm for 4 minutes to obtain a preliminarily uniform mixed raw material.

[0064] Step 2: In a vacuum stirring device, mix the mixed raw materials with water in a ratio of 27% of the total weight of the welding wire core, stir while adding water, continue stirring for 2.5 minutes after the water is added, and then stir at a stirring speed of 175 rpm for 13 minutes to obtain a uniformly mixed and bubble-free mud core blank.

[0065] Step 3: first heat and melt the mud-like flux core blank to obtain a molten flux core, and then pour the molten flux core into the hollow part of the seamless welding wire outer skin, while keeping the vacuum equipment running until the molten flux core fills the hollow part of the seamless welding wire outer skin to obtain the welding wire blank.

[0066] Step 4: Place the welding wire blank in a vacuum environment for cooling treatment, so that the molten core solidifies in the outer skin of the hollow welding wire to obtain a vacuum seamless flux-cored welding wire.

[0067] Example 4 The vacuum seamless flux-cored welding wire of this embodiment includes a seamless welding wire outer skin and a welding wire flux core. The seamless welding wire outer skin is a hollow structure with openings at both ends and is integrally formed; the welding wire flux core is filled in the hollow part of the seamless welding wire outer skin by vacuum extraction; the welding wire flux core includes the following components and the weight proportions of each component are respectively: 35 parts of rutile, 16 parts of ferrosilicon powder, 6 parts of nickel powder, 8 parts of manganese iron alloy, 4 parts of chromium powder, 6 parts of dolomite, 3 parts of fluorite, 1 part of niobium powder, and 2 parts of titanium-boron alloy.

[0068] Step 1: Place the weighed raw materials of each component of the welding wire core in a vacuum stirring device, stir at a stirring speed of 75 rpm for 5 minutes to obtain a preliminarily uniform mixed raw material.

[0069] Step 2: In a vacuum stirring device, mix the mixed raw materials with water in a ratio of 30% of the total weight of the welding wire core, stir while adding water, continue stirring for 3 minutes after the water is added, and then stir at a stirring speed of 200 rpm for 15 minutes to obtain a uniformly mixed and bubble-free mud core blank.

[0070] Step 3: first heat and melt the mud-like flux core blank to obtain a molten flux core, and then pour the molten flux core into the hollow part of the seamless welding wire outer skin, while keeping the vacuum equipment running until the molten flux core fills the hollow part of the seamless welding wire outer skin to obtain the welding wire blank.

[0071] Step 4: Place the welding wire blank in a vacuum environment for cooling treatment, so that the molten core solidifies in the outer skin of the hollow welding wire to obtain a vacuum seamless flux-cored welding wire.

[0072] Comparative Example 1 Core material components: 32 parts of rutile, 14 parts of ferrosilicon powder, 5 parts of nickel powder, 6 parts of ferromanganese alloy, 3 parts of chromium powder, 4 parts of dolomite, 2.5 parts of fluorite, 0.8 parts of niobium powder, and 1.5 parts of titanium-boron alloy.

[0073] The production method of flux-cored welding wire is as follows: the steel strip is rolled into a U-shaped groove, and then the mixed flux core is filled into the U-shaped groove; then the flux-cored welding wire is obtained by closing, reducing the diameter, drawing and winding the wire.

[0074] Comparative Example 2 Core material components: 33 parts of rutile, 15 parts of ferrosilicon powder, 5.5 parts of nickel powder, 7 parts of ferromanganese alloy, 3.5 parts of chromium powder, 5 parts of dolomite, 2.8 parts of fluorite, 0.9 parts of niobium powder, and 1.8 parts of titanium-boron alloy.

[0075] The production method of flux-cored welding wire is as follows: the steel strip is rolled into a U-shaped groove, and then the mixed flux core is filled into the U-shaped groove; then the flux-cored welding wire is obtained by closing, reducing the diameter, drawing and winding the wire.

[0076] According to relevant standards and specifications, various welding tests were conducted on the vacuum seamless flux-cored welding wire and flux-cored welding wire provided in the above-mentioned Examples 1 to 4 and Comparative Examples 1 and 2. The welding current was 150A to 200A, and a mixed gas of argon and carbon dioxide was used as the shielding gas during welding. The gas flow rate was 10 to 15 L / min. The welding process performance is as follows: Table 1 Mechanical properties of weld Table 2 Stability of welding process Table 3 Core stability and moisture resistance test The test results of Examples 1 to 3 and Comparative Examples 1 and 2 show that during the welding process, the vacuum seamless flux-cored welding wire provided by the present invention has a stable arc, less spatter, and easy slag removal, has high tensile strength and yield strength, can provide a stronger bearing capacity for the welded structure, and has good moisture-proof properties.

[0077] It is to be understood that the present invention is described by some embodiments, and it is known to those skilled in the art that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the scope of protection of the present invention.

Claims

1. A vacuum seamless flux-cored welding wire, characterized in that: It includes a seamless welding wire sheath and a welding wire core, wherein the seamless welding wire sheath is a hollow structure with openings at both ends and formed in one piece; the welding wire core is filled in the hollow part of the seamless welding wire sheath by vacuuming; the welding wire core includes the following components and the weight proportions of each component are respectively: 30-35 parts of rutile, 12-16 parts of ferrosilicon powder, 4-6 parts of nickel powder, 5-8 parts of ferromanganese alloy, 2-4 parts of chromium powder, 3-6 parts of dolomite, 2-3 parts of fluorite, 0.5-1 part of niobium powder, and 1-2 parts of titanium-boron alloy.

2. The vacuum seamless flux-cored welding wire according to claim 1, characterized in that: The particle size of the welding wire core is 60-200 meshes.

3. The vacuum seamless flux-cored welding wire according to claim 1 or 2, characterized in that: The outer skin of the seamless welding wire is made of any one or more materials selected from the group consisting of copper, silver and nickel.

4. A filling process for a vacuum seamless flux-cored welding wire as claimed in any one of claims 1 to 3, characterized in that: The steps include: Mixing raw materials of various components of welding wire core with liquid additives to obtain mud-like core blanks; Taking the mud-like core blank material and heating and melting it to obtain a molten core; Take the seamless welding wire outer skin prepared in advance, and connect the vacuum equipment to one end of the seamless welding wire outer skin for vacuum treatment; Pouring the molten flux core into the hollow part of the seamless welding wire outer skin, while keeping the vacuum equipment running, until the molten flux core fills the hollow part of the seamless welding wire outer skin, to obtain a welding wire blank; The welding wire blank is placed in a vacuum environment for cooling treatment, so that the molten flux core is solidified inside the hollow welding wire to obtain a vacuumized seamless flux cored welding wire.

5. The filling process according to claim 4, characterized in that: The step of mixing the raw materials of the welding wire core components with the liquid additive to obtain a mud-like core blank specifically includes the following sub-steps: The raw materials of the welding wire core components are mixed with an appropriate amount of water in the following proportions: 30-35 parts of rutile, 12-16 parts of ferrosilicon powder, 4-6 parts of nickel powder, 5-8 parts of ferromanganese alloy, 2-4 parts of chromium powder, 3-6 parts of dolomite, 2-3 parts of fluorite, 0.5-1 part of niobium powder, and 1-2 parts of titanium-boron alloy, and placed in a vacuum stirring device for stirring until muddy to obtain a bubble-free muddy core blank.

6. The filling process according to claim 4, characterized in that: The step of mixing the raw materials of the welding wire core components with the liquid additive to obtain a mud-like core blank specifically includes the following sub-steps: The weighed raw materials of each component of the welding wire core are placed in a vacuum stirring device, and stirred at a stirring speed of 50-100 rpm for 3-5 min to obtain a preliminarily uniform mixed raw material; Take 20% to 30% of the total mass of the mixed raw material and slowly add water to the mixed raw material. Stirring is performed during the water addition process. After the water is added, stirring is continued for 2 to 3 minutes, and stirring is performed at a stirring speed of 150 to 200 rpm for 10 to 15 minutes to obtain a uniformly mixed and bubble-free muddy core blank.

7. The filling process according to claim 4, characterized in that: The pre-prepared seamless welding wire outer skin specifically comprises the following sub-steps: One or more materials of copper, silver and nickel prepared in advance are melted and cast to obtain a rod-shaped blank; The rod-shaped blank is placed in a heating furnace for preheating, and the preheated rod-shaped blank is subjected to a perforation process to obtain a first welding wire sheath blank having a hollow structure; The first welding wire sheath blank is subjected to a first drawing and reducing process to obtain a second welding wire sheath blank; Annealing the second welding wire sheath stock to obtain a third welding wire sheath stock; The third welding wire sheath blank is subjected to a second drawing and diameter reduction to obtain a fourth welding wire sheath blank; The fourth welding wire sheath blank is cleaned and polished to obtain a seamless welding wire sheath.

8. The filling process according to claim 7, characterized in that: After the pre-prepared one or more materials of copper, silver and nickel are melted and cast, they are cooled and turned to obtain a rod-shaped outer skin blank without oxide scale.

9. The filling process according to claim 7, characterized in that: In the step of placing the rod-shaped outer skin blank in a heating furnace for preheating, the temperature is raised to 500-700° C. at a heating rate of 5-10° C. / min and then kept warm for 15-30 minutes.

10. The filling process according to claim 7, characterized in that: The annealing of the second welding wire outer sheath blank specifically comprises the following sub-steps: After cleaning the second welding wire sheath blank, the temperature in the annealing furnace is increased to 400-700° C. at a heating rate of 5-10° C. / min, and after being kept warm for 1-3 hours, the blank is cooled to room temperature along with the furnace to obtain a third welding wire sheath blank.

Images