Manufacturing method and manufacturing system for short-process high-temperature alloy welding wire

Abstract

The invention discloses a short-process high-temperature alloy welding wire manufacturing method and system, and relates to the field of high-temperature alloy welding wire manufacturing. The short-process high-temperature alloy welding wire manufacturing method comprises the following steps: 1, medium-frequency smelting in a vacuum environment: A, feeding raw materials and vacuumizing; b, smelting: starting a medium-frequency smelting furnace, and gradually raising the temperature to a smelting temperature; the method comprises the following steps: (1) smelting a high-temperature alloy raw material into molten steel; (2) oxygen in the molten steel is replaced by carbon, and oxycarbide gas is generated; (3) nitrogen and hydrogen in the molten steel are separated out as gas; (4) burning out and vaporizing sulfides in the molten steel; c, refining; 2, horizontal continuous casting under inert gas protection; and 3, post-treatment. A short-process high-temperature alloy welding wire manufacturing system comprises a vacuum chamber, a vacuum lock, a medium-frequency smelting furnace, a crystallizer, a throwing machine, a bottom blowing device and an inner hole gas injection device. On the basis of the technology of'intermediate-frequency smelting in the vacuum environment and horizontal continuous casting under inert gas protection ', short-process, continuous and low-cost production of the high-temperature alloy welding wire is achieved, and the product purity is high.

Description

Technical Field

[0001] The present invention relates to the field of manufacturing superalloy welding wires, in particular to a manufacturing method and a manufacturing system for superalloy welding wires with a short process. Background Art

[0002] Due to their characteristics such as high temperature resistance, corrosion resistance, and high strength, superalloy welding wires are widely used in many fields. For example: I. In the aerospace field, they are used for the connection and repair of engine components, key components such as turbine blades and combustion chambers, to meet the working requirements of aircraft in extreme environments; II. In the petrochemical field, they are used for the connection and repair of equipment such as pipelines, valves, and reactors, and can withstand high temperatures, high pressures, and corrosive media; III. In the power industry field, they are used for the connection and repair of key components of equipment such as gas turbines, steam turbines, and generators to ensure the stable operation of power equipment.

[0003] As Figure 4 shown, the current production process of superalloy welding wires mainly includes the following key steps: S01, Vacuum Induction Melting: The raw materials are introduced into a vacuum induction melting furnace, and the furnace is evacuated for melting. Since the pressure decreases, the solubility of oxygen in the molten steel decreases, and then oxygen precipitates to achieve deoxidation; then the molten steel is discharged into a mold, and after the molten steel is completely solidified, a primary melting ingot is obtained; due to the inherent defects such as rough surface (pits), shrinkage cavities, segregation, and slag entrainment in the primary melting ingot, subsequent electroslag remelting process is required to eliminate them.

[0004] S02, Electroslag Remelting: An electroslag remelting furnace (the structure of a typical electroslag remelting furnace can refer to CN207016840U: Single-column double-conductive cross-arm ingot-pulling type electroslag remelting furnace device) is used to remelt the primary melting ingot to manufacture a secondary remelting ingot. The secondary remelting ingot basically eliminates several inherent defects existing in the primary melting ingot, and a small part of the remaining defects need to be eliminated through subsequent forging processes; Introduction to the equipment structure of electroslag remelting: The single-column double-conductive cross-arm ingot-pulling type electroslag remelting furnace device includes a workbench erected above the bottom plate, an upper column located at the upper end of the workbench, a lower column located at the lower end of the workbench, and a mold located on the side of the workbench; a first electrode feeding arm and a second electrode feeding arm are provided on the upper column; both the first electrode feeding arm and the second electrode feeding arm move up and down along the upper column; a first slag ingot feeding arm and a second slag ingot feeding arm are provided on the ingot-pulling column, and both the first slag ingot feeding arm and the second slag ingot feeding arm move up and down along the ingot-pulling column; Introduction to the operation process of electroslag remelting: Place the arc starter on the dummy bar inserted from the bottom of the mold, and switch on the high voltage to strike an arc. Control the first and second electrode feeding arms to be alternately energized to clamp the consumable electrode (ingot of the first melting) and move it continuously downward. At the same time, the first and second slag ingot feeding arms are alternately energized to clamp the electroslag ingot (ingot of the second melting) and move it downward, and discharge it through the groove on the bottom plate. Introduction to the working principle of electroslag remelting: When the equipment is working, the operator prepares for remelting according to the process regulations. After striking the arc for slagging, the consumable electrode (ingot of the first melting), slag pool, metal molten pool, electroslag ingot, and dummy bar cross arm form a circuit through the short-circuit wire and transformer. During the power-on process, the slag pool releases Joule heat, gradually melting the end of the consumable electrode. The molten metal converges into droplets, passes through the slag pool, and falls into the crystallization pool to form a metal molten pool. Under the action of water cooling, it quickly solidifies to form an electroslag ingot (ingot of the second melting).

[0005] S03, Forging: Forge the ingot of the second melting at a specific temperature condition into a square billet of a specific size. This process includes steps such as annealing and grinding. This process is used to eliminate inherent defects such as porosity and segregation in the ingot of the second melting, and improve the tissue density and refine the grains, providing a good foundation for subsequent hot rolling.

[0006] S04, Post-treatment: The square billet is processed into a wire rod that meets the requirements of subsequent drawing through hot continuous rolling. The wire rod goes through solution treatment, pickling, rough drawing, and finish drawing processes in sequence, gradually reducing the wire diameter of the welding wire to the process requirements, and then the finished product of the superalloy welding wire is obtained.

[0007] Thus, the current production process of superalloy welding wire has the following deficiencies: 1. Long process flow: The core processes before post-treatment include two meltings and one forging and shaping, and the two meltings are completed in different equipment, making the process flow long.

[0008] 2. High production cost: The core processes before post-treatment include two meltings and one forging and shaping. Scrap, losses, and labor costs will be generated during the transfer of each process, ultimately resulting in high production costs.

[0009] 3. Poor continuity: The core processes before post-treatment include two meltings and one forging and shaping. The ingot cannot be seamlessly connected between any two adjacent processes, but requires manual transfer.

[0010] 4. High raw material requirements; It is difficult to remove sulfur elements in the raw materials in the above process. Sulfur in the raw materials will be carried into the final product with each process. Therefore, it can only be controlled at the source, and only raw materials with sulfur content within the required range of the finished product can be purchased.

[0011] In summary, on the premise of ensuring the product quality of superalloy welding wires, simplifying the process flow, reducing production costs, and lowering raw material requirements have always been the key research directions for related enterprises. Summary of the Invention

[0012] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a manufacturing method and system for short-process superalloy welding wires. It solves the problems of long production process flow, high production cost, poor continuity, and high raw material requirements of existing superalloy welding wires.

[0013] The technical solution of the present invention is as follows: The manufacturing method of short-process superalloy welding wires includes the following steps: S01, intermediate frequency melting in a vacuum environment: A. Feeding raw materials and evacuating: Put superalloy raw materials and carbon for deoxidation into the intermediate frequency melting furnace, and evacuate the inner cavity of the vacuum chamber where the intermediate frequency melting furnace is located; B. Melting: Start the intermediate frequency melting furnace, and gradually increase to the melting temperature in the way of "raising power - maintaining power" with a stepped increase. The melting process lasts for at least 190 minutes, and it is ensured that all the alloy materials are liquefied within the first 40 minutes of the melting process; C. Refining: Adjust the power of the intermediate frequency melting furnace to make the molten steel reach the preset refining temperature; then perform the following operations simultaneously: ①. Keep warm for at least 15 minutes to further discharge oxygen, nitrogen, hydrogen, and sulfur elements in the molten steel; ②. Blow inert gas from the bottom into the inner cavity of the intermediate frequency melting furnace through the bottom blowing device. The generated bubbles absorb the precipitated gas during the upward floating process. When the bubbles reach the molten steel surface, they are discharged into the inner cavity of the vacuum chamber and evacuated by the vacuum pump; S02, horizontal continuous casting under inert gas protection: Adjust the power of the intermediate frequency melting furnace. After the molten steel temperature reaches the starting casting temperature, stop evacuating, and perform the following operations simultaneously: ①. Keep blowing inert gas from the bottom to cover the molten steel surface with a protective gas; ②. The refined molten steel is discharged from the nozzle of the intermediate frequency melting furnace and flows into the inside of the mold to form the shell of the billet; The billet is continuously pulled out of the inside of the mold to the outside of the vacuum chamber by the billet pulling machine located outside the vacuum chamber; Cut the pulled billet to the required length to obtain the semi-finished product of the superalloy welding wire; S03, post-treatment: The semi-finished product of the superalloy welding wire is peeled by a lathe to remove the surface defects on its outer cylindrical surface; Then, a wire rod that meets the subsequent drawing requirements is prepared through a hot continuous rolling process; The wire rod undergoes solution treatment, pickling, rough drawing, and finish drawing processes in sequence to gradually reduce the wire diameter to the process requirements, and the finished product of the superalloy welding wire is obtained.

[0014] A further technical solution of the present invention is: in step S02, the operations performed simultaneously also include: ③. The ingot guide rod and the billet are respectively passed through the vacuum lock on the outer wall of the vacuum chamber, and inert gas is injected into the inner hole of the vacuum lock through the inner hole gas injection device to prevent external air from entering the inner cavity of the vacuum chamber through the gap between the ingot guide rod and the vacuum lock or the billet and the vacuum lock.

[0015] A further technical solution of the present invention is: in step S02, one end of the initial position of the dummy rod is located outside the vacuum chamber, and the other end passes through the vacuum lock and is located in the inner cavity of the vacuum chamber and extends into the crystallizer; during the horizontal continuous casting process, one end of the billet passes through the vacuum lock and is located in the inner cavity of the vacuum chamber, and the other end is located outside the vacuum chamber; when the dummy rod moves in the vacuum lock, an annular sealing surface is formed between the dummy rod and the vacuum lock, and when the billet passes through the vacuum lock and moves, an annular sealing surface is formed between the billet and the vacuum lock.

[0016] A further technical solution of the present invention is: in step S01, the carbon used for deoxidation is carbon powder, and the addition amount thereof is 0.015%-0.025% of the weight of the high-temperature alloy raw material.

[0017] A further technical solution of the present invention is: in step S01, the vacuum degree in the inner cavity of the vacuum chamber is maintained below 10Pa by evacuating the vacuum chamber.

[0018] A further technical solution of the present invention is: in steps S01-S02, the inert gas is argon with a purity of more than 99.99%, krypton with a purity of more than 99.99%, or helium with a purity of more than 99.99%.

[0019] A further technical solution of the present invention is: in steps S01-S02, the amount of bottom-blown inert gas is based on the fluctuation of the molten steel level and the fact that the molten steel does not leak out.

[0020] The technical solution of the present invention is: a short process high temperature alloy welding wire manufacturing system, which is matched with the above-mentioned short process high temperature alloy welding wire manufacturing method, and includes a vacuum chamber, a vacuum lock, a medium frequency melting furnace, a crystallizer, a billet drawing machine, a bottom blowing device and an inner hole gas injection device; The vacuum chamber comprises a chamber body with an open upper end and an upper cover sealed and installed at the upper open end of the chamber body. The chamber body is provided with an inner cavity for accommodating the medium frequency melting furnace and the crystallizer. The chamber body is provided with a negative pressure exhaust port connected to the inner cavity. The upper cover is provided with an operation port for adding materials and measuring temperature and sampling. A balancing valve is provided inside the operation port. The vacuum lock is fixedly mounted on the side wall of the vacuum chamber, and is provided with an inner hole for the ingot and the dummy rod to pass through in a sealed manner, and the two ends of the inner hole are respectively connected to the inner cavity of the vacuum chamber and the outside of the vacuum chamber, and the outside is provided with an air injection hole connected to the inner hole and an air outlet hole connected to the inner hole; The intermediate frequency melting furnace is arranged in the inner cavity of the vacuum chamber. The upper end of the intermediate frequency melting furnace is provided with an open mouth, the lower end is provided with a water outlet, and the bottom is provided with an installation opening. The open mouth of the intermediate frequency melting furnace is open in the inner cavity of the vacuum chamber; The mold is arranged in the inner cavity of the vacuum chamber. The two ends of the mold are respectively provided with an inlet and an outlet. The inlet of the mold is communicated with the water outlet of the intermediate frequency melting furnace; the mold is a water-cooled horizontal continuous casting mold; The billet pulling machine is arranged outside the vacuum chamber. One end of the billet pulling machine is provided with a dummy bar. The axis line of the dummy bar coincides with the axis line of the inner hole of the vacuum lock. The dummy bar is opposite to the outlet of the mold and is used to pull out the cast billet; The bottom blowing device is installed on the installation opening of the intermediate frequency melting furnace and is used to blow inert gas into the inner cavity of the intermediate frequency melting furnace; The inner hole gas injection device is connected to the gas injection port of the vacuum lock and is used to inject inert gas into the inner hole of the vacuum lock.

[0021] A further technical solution of the present invention is that the bottom blowing device includes a porous plug, a steel pipe and an air inlet pipe A; the porous plug is hermetically and fixedly installed in the installation opening of the intermediate frequency melting furnace. The porous plug has the characteristics of isolating molten steel and permeating gas. The upper end of the porous plug is located in the inner cavity of the intermediate frequency melting furnace, and the lower end of the porous plug is located outside the intermediate frequency melting furnace; the upper port of the steel pipe is fixedly connected to the lower end of the porous plug; one end of the air inlet pipe A is connected to the lower port of the steel pipe, and the other end is communicated with the gas source for providing inert gas.

[0022] A further technical solution of the present invention is that the inner hole gas injection device includes an exhaust pipe and an air inlet pipe B; one end of the exhaust pipe is hermetically and fixedly installed on the exhaust hole of the vacuum lock, and the other end is communicated with the atmosphere; one end of the air inlet pipe B is hermetically and fixedly installed on the gas injection hole of the vacuum lock, and the other end is communicated with the gas source for providing inert gas.

[0023] A further technical solution of the present invention is that the vacuum lock includes a first sleeve, an expansion ring, a sealing ring, and a pressing assembly; the first sleeve is in the shape of a sleeve with both ends open, and its inner hole includes an intermediate hole section and end hole sections provided on both sides of the intermediate hole section. Annular step surfaces are respectively provided between the intermediate hole section and the two end hole sections. The aperture of the intermediate hole section is smaller than that of the two end hole sections. An air injection hole communicating with the intermediate hole section and an exhaust hole communicating with the intermediate hole section are provided on the outer surface of the first sleeve. Flange disks A are welded to both end faces of the first sleeve respectively, and a plurality of threaded holes evenly distributed in a ring are provided on the flange disks A; at least three expansion rings are stacked with their end faces in contact to form a group, and two groups of expansion rings are respectively installed in the two end hole sections of the first sleeve. The inner holes of all the expansion rings in each group of expansion rings are sequentially communicated to form a billet sealing section; two sealing rings are respectively installed in the two end hole sections of the first sleeve, and the end face of the sealing ring contacts the outermost expansion ring in the end hole section. Two groups of pressing assemblies are respectively installed in the end hole sections at both ends of the first sleeve, and are used to press the sealing ring and a group of expansion rings in the end hole section against the annular step surface; the pressing assembly includes a second sleeve, a screw rod, and a nut; the front end of the second sleeve is inserted into the end hole section of the first sleeve, and the end face of its front end contacts the end face of the sealing ring. A flange disk B is welded to the end face of the rear end of the second sleeve, and through holes for the rod are provided on the flange disk B at positions corresponding to and having the same number as the threaded holes on the flange disk A; the number of screw rods and nuts is the same as the number of through holes for the rod on the flange disk B; all the screw rods respectively pass through the respective through holes for the rod on the second sleeve and are screwed into the threaded holes at the corresponding positions of the first sleeve, and a plurality of nuts are respectively threadedly connected to the respective screw rods and are all abutted against the flange disk B; by adjusting the nuts, the front end of the second sleeve presses the sealing ring and a group of expansion rings in the end hole section against the annular step surface.

[0024] The present invention has the following advantages compared with the prior art: 1. Based on the original "medium-frequency melting in a vacuum environment + horizontal continuous casting under inert gas protection" process, it realizes the short-process, continuous, and low-cost production of superalloy welding wires. The products have high purity, good compactness, uniform crystal structure, and low center crack and shrinkage porosity. The short process is reflected in: eliminating the electroslag remelting and forging processes, which is equivalent to shortening the core processes before post-treatment. The continuity is reflected in: seamless docking and continuous discharging are achieved in the core processes before post-treatment. The low cost is reflected in: the shortening of the process flow and the continuity of the process flow reduce the labor cost, waste, and losses.

[0025] 2. During the intermediate frequency melting process, the gas elements (O, N, and H) and S element in the molten steel are effectively reduced, significantly improving the purity of the molten steel. As a result, the indicators of the billets obtained by subsequent horizontal continuous casting are equivalent to those of the ingots manufactured by the traditional "vacuum induction melting + electroslag remelting" process. The principle of improving the purity of molten steel is as follows: In a vacuum environment, a. The solubility of dissolved oxygen, dissolved nitrogen, and dissolved hydrogen in the molten steel decreases and precipitates. During the process of the bubbles generated by bottom blowing inert gas (argon gas is blown upward from the bottom of the intermediate frequency melting furnace) floating in the molten steel, the above-precipitated gases are absorbed, causing the bubbles to grow. When the bubbles reach the liquid surface of the molten steel, they are discharged into the inner cavity of the vacuum chamber and evacuated by the vacuum pump. b. The bubbles generated by bottom blowing inert gas (argon gas is blown upward from the bottom of the intermediate frequency melting furnace) form a local vacuum in the molten steel, creating a pressure difference at the interface between the bubbles and the molten steel, causing the dissolved oxygen and dissolved nitrogen dissolved in the molten steel to be continuously sucked into the bubbles, making the bubbles grow continuously. When the bubbles reach the liquid surface of the molten steel, they are discharged into the inner cavity of the vacuum chamber and evacuated by the vacuum pump. c. There are some suspended inclusions in the molten steel. When the above bubbles come into contact with the inclusions, the inclusions are adsorbed on the bubble wall and finally transferred to the liquid surface of the molten steel as the bubbles float upward. d. The S element in the molten steel is burned and vaporized during the melting process and discharged into the inner cavity of the vacuum chamber and evacuated by the vacuum pump.

[0026] 3. It adopts measures such as argon stirring at the furnace bottom and creating a vacuum environment to ensure the high purity of the molten steel. Moreover, both melting and horizontal continuous casting are completed in the vacuum chamber (under a vacuum environment), effectively solving the problem of secondary oxidation of the molten steel. The vacuum chamber realizes the construction of a vacuum environment at the structural design level: a. The upper end of the vacuum chamber is provided with an operation port for temperature measurement, sampling, or adding materials. When no material addition or temperature measurement and sampling operations are performed, the balance valve is in a closed state to ensure the sealing of the entire vacuum chamber 1. When performing material addition or temperature measurement and sampling operations, after a sealed feeder (the sealed feeder is an existing technology and is not shown in the figure) or a temperature measurement and sampling device (the temperature measurement and sampling device is an existing technology and is not shown in the figure) is hermetically docked with the operation port, the balance valve is then opened. b. Sealing rings and expansion rings are provided in the inner hole of the vacuum lock. The sealing ring matches the dummy bar and is used for sealing when the dummy bar passes through the inner hole of the vacuum lock. The expansion ring matches the billet and is used for sealing when the billet passes through the inner hole of the vacuum lock. When the billet has not entered the inner hole of the vacuum lock, the expansion ring is at room temperature, and the inner diameter size of the expansion ring is larger than the outer diameter sizes of the billet and the dummy bar, so it will not interfere with the movement of the dummy bar. When the billet enters the inner hole of the vacuum lock, the sealing ring is burned and vaporized, and the heat is transferred to the expansion ring, causing the expansion ring to expand due to heat, and then the inner diameter of the expansion ring shrinks to match the outer diameter size of the billet. At this time, a dynamic sealing fit relationship is formed between the inner hole of the expansion ring and the outer circular surface of the billet.

[0027] 5. During the horizontal continuous casting process, an inner hole gas injection device is used to inject inert gas into the inner hole of the vacuum lock to prevent external air from entering the inner cavity of the vacuum chamber through the gap between the ingot guide rod and the inner hole of the vacuum lock or between the ingot and the inner hole of the vacuum lock, thereby oxidizing the molten steel.

[0028] The present invention is further described below in conjunction with the figures and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a process flow chart of the present invention; Figure 2 It is a structural schematic diagram of a short process high temperature alloy welding wire manufacturing system; Figure 3 It is a schematic diagram of the structure of the vacuum lock; Figure 4 The figure is a flow chart of the existing high-temperature alloy welding wire production process.

[0030] Legend: vacuum chamber 1; chamber body 11; upper cover 12; operating port 13; balancing valve 14; negative pressure exhaust port 15; vacuum lock 2; first sleeve 21; gas injection hole 211; exhaust hole 212; flange A213; expansion ring 22; sealing ring 23; second sleeve 24; flange B241; screw 25; nut 26; medium frequency melting furnace 3; opening 31; water inlet 32; crystallizer 4; throwing machine 5; air-permeable brick 61; steel pipe 62; air inlet pipe A63; exhaust pipe 71; air inlet pipe B72. DETAILED DESCRIPTION Example 1

[0031] This embodiment takes the high temperature alloy welding wire made of the high temperature alloy grade K418 as an example. Figure 1 As shown, the short process high temperature alloy welding wire manufacturing method has the following steps: S01, frequency melting in vacuum environment: A. Raw material feeding and vacuuming: Before the high-temperature alloy raw materials are fed into the furnace, they are weighed again, the proportion of the ingredients is re-checked, and finally the alloy materials are selected and added according to the proportion of the finished product; the high-temperature alloy raw materials and carbon for deoxidation are fed into the medium frequency melting furnace, and the vacuum chamber of the medium frequency melting furnace is vacuumed; B. Melting: Start the intermediate frequency melting furnace and gradually increase the temperature to the melting temperature (the melting temperature is 1560 ± 5 °C) in the way of "raising power - maintaining power" with a stepped increase. The melting process lasts for at least 190 minutes, and ensure that all the alloy materials are liquefied within the first 40 minutes of the melting process. The following things happen during the above process: ①. The superalloy raw materials are melted into molten steel; ②. The oxygen in the molten steel is replaced by carbon, generating carbon oxide gas, which is discharged into the inner cavity of the vacuum chamber and evacuated by the vacuum pump; ③. The solubility of nitrogen and hydrogen in the molten steel decreases in the vacuum environment and precipitates as gas, which is discharged into the inner cavity of the vacuum chamber and evacuated by the vacuum pump; ④. The sulfides in the molten steel are burned and vaporized during the melting process and discharged into the inner cavity of the vacuum chamber and evacuated by the vacuum pump; C. Refining: Adjust the power of the intermediate frequency melting furnace. When the temperature of the molten steel reaches the preset refining temperature of 1580 ± 5 °C, perform the following operations simultaneously: ①. Keep warm for 15 minutes to further discharge the oxygen, nitrogen, hydrogen, and sulfur elements in the molten steel; ②. Blow inert gas from the bottom into the inner cavity of the intermediate frequency melting furnace through the bottom blowing device. During the upward floating process of the generated bubbles, the bubbles absorb the precipitated gas and grow. When the bubbles reach the liquid surface of the molten steel, they are discharged into the inner cavity of the vacuum chamber and evacuated by the vacuum pump.

[0032] S02, Inert gas protection level continuous casting: Reduce the power of the intermediate frequency melting furnace. After the temperature of the molten steel reaches the casting start temperature of 1500 ± 10 °C, stop vacuum pumping. At the same time, perform the following operations: ①. Bottom blow inert gas: Keep blowing inert gas to cover the molten steel surface with protective gas, avoiding the air that penetrates into the inner cavity of the vacuum chamber through the gap from contacting with the molten steel and oxidizing the molten steel; ②. Ingot drawing and billet casting: The intermediate frequency melting furnace discharges the refined molten steel through the nozzle. The molten steel flows into the inside of the mold located in the inner cavity of the vacuum chamber to form the billet shell of the casting; The ingot drawing machine located outside the vacuum chamber drives the ingot rod to move horizontally, continuously pulling the casting out of the inside of the mold to the outside of the vacuum chamber, which is called ingot drawing and billet casting. Cut the drawn casting to the required length (i.e., the length required by the process) to obtain the semi-finished product of the superalloy welding wire.

[0033] S03, Post-treatment: The semi-finished product of the superalloy welding wire is peeled by a lathe to remove the surface defects (inherent defect of horizontal continuous casting: cold lattice) on its outer cylindrical surface; Then, prepare the wire rod that meets the subsequent drawing requirements through the hot continuous rolling process; The wire rod goes through the solution treatment, pickling, rough drawing, and finish drawing processes in sequence, gradually reducing the diameter of the welding wire to the process requirements to obtain the finished product of the superalloy welding wire.

[0034] Preferably, in step S01, keep the vacuum degree in the inner cavity of the vacuum chamber below 8 Pa.

[0035] Preferably, in step S01, the static head height during melting the molten steel ≥ 20 cm to ensure that the molten steel does not overflow when stirred and fluctuated by the inert gas.

[0036] Preferably, under the premise that the finished high-temperature alloy welding wire contains active elements (including Al, Ti, Zr or Hf), step S01 also includes sub-step D following sub-step C; D, replenishing material: shut down the medium frequency melting furnace and cool it to 1380°C, and then replenish the material of the active elements by vacuum feeding (using a vacuum feeder to achieve vacuum feeding, the structure and principle of the vacuum feeder are the existing technology).

[0037] Preferably, in step S02, the billet pulling speed is 0.5-1.5 m / min.

[0038] Preferably, in step S02, the vacuum degree in the inner cavity of the vacuum chamber is maintained below 65000 Pa.

[0039] Preferably, in step S02, the operations performed simultaneously also include: ③. Injecting inert gas into the inner hole of the vacuum lock: the ingot guide rod and the cast billet respectively pass through the inner hole of the vacuum lock located on the outer wall of the vacuum chamber, and the ingot guide rod and the cast billet respectively form annular sealing surfaces with the vacuum lock, and inert gas is injected into the inner hole of the vacuum lock through the inner hole gas injection device to prevent external air from entering the inner cavity of the vacuum chamber through the gap between the ingot guide rod and the inner hole of the vacuum lock or the gap between the cast billet and the inner hole of the vacuum lock, and oxidizing the molten steel.

[0040] Preferably, in step S02, one end of the initial position of the ingot guide rod is located outside the vacuum chamber, and the other end passes through the vacuum lock on the outer wall of the vacuum chamber and is located in the inner cavity of the vacuum chamber and extends into the interior of the crystallizer; during the horizontal continuous casting process, one end of the billet passes through the vacuum lock on the outer wall of the vacuum chamber and is located in the inner cavity of the vacuum chamber, and the other end is located outside the vacuum chamber; when the ingot guide rod moves in the vacuum lock, an annular sealing surface is formed between the ingot guide rod and the vacuum lock, and when the billet moves through the vacuum lock, an annular sealing surface is formed between the billet and the vacuum lock.

[0041] Preferably, in step S03, the peeling depth is based on the removal of defects on the outer circumferential surface of the semi-finished high-temperature alloy welding wire.

[0042] Preferably, in steps S01-S02, the inert gas is argon with a purity of more than 99.99%, krypton with a purity of more than 99.99%, or helium with a purity of more than 99.99%.

[0043] Preferably, in steps S01-S02, the amount of bottom-blown inert gas is based on the fact that the molten steel level fluctuates and the molten steel does not leak.

[0044] like Figures 2-3 As shown, the short process high temperature alloy welding wire manufacturing system is matched with the above-mentioned short process high temperature alloy welding wire manufacturing method, which includes a vacuum chamber 1, a vacuum lock 2, a medium frequency melting furnace 3, a crystallizer 4, a billet drawing machine 5, a bottom blowing device and an inner hole gas injection device.

[0045] The vacuum chamber 1 includes a chamber body 11 with an open upper end and an upper cover 12 hermetically installed at the open upper end of the chamber body 11. An inner cavity for accommodating an intermediate frequency melting furnace and a crystallizer is provided inside the chamber body 11. A negative pressure air extraction port 15 communicating with the inner cavity is provided on the chamber body 11. The negative pressure air extraction port 15 is communicated with a vacuum pump (not shown in the figure) located outside the vacuum chamber 1 through an air pipeline. An operation port 13 for adding materials and measuring temperature and sampling is provided on the upper cover 12, and a balance valve 14 (for balancing the pressures on both sides of the valve) is provided inside the operation port 13.

[0046] The vacuum lock 2 is fixedly installed on the side wall of the vacuum chamber 1. It has an inner hole through which the cast slab and the dummy bar pass through in a sealed manner. The two ends of the inner hole are respectively communicated with the inner cavity of the vacuum chamber 1 and the outside of the vacuum chamber 1. Its outside is provided with an air injection hole communicated with the inner hole and an exhaust hole communicated with the inner hole. The vacuum lock 2 includes a first sleeve 21, an expansion ring 22 (packing), a sealing ring 23 and a pressing assembly. The first sleeve 21 is in the shape of a sleeve with both ends open. Its inner hole includes a middle hole section and end hole sections arranged on both sides of the middle hole section. There are annular stepped surfaces respectively between the middle hole section and the two end hole sections. The aperture of the middle hole section is smaller than that of the two end hole sections. The air injection hole 211 communicated with the middle hole section and the exhaust hole 212 communicated with the middle hole section are provided on the outer surface of the first sleeve 21. Flange plates A 213 are welded on the two end faces of the first sleeve 21 respectively. A plurality of threaded holes are arranged in a circular pattern on the flange plates A 213. At least three expansion rings 22 are stacked with their end faces in contact to form a group. Two groups of expansion rings 22 are respectively installed in the two end hole sections of the first sleeve 21. The inner holes of all the expansion rings 22 in each group of expansion rings 22 are sequentially communicated to form a cast slab sealing section. Two sealing rings 23 are respectively installed in the two end hole sections of the first sleeve 21. And the end face of the sealing ring 23 contacts the outermost expansion ring 22 in the end hole section (the outermost expansion ring 22 is the one farthest from the annular stepped surface). The inner hole of the sealing ring 23 forms a dummy bar sealing section. Two groups of pressing assemblies are respectively installed in the end hole sections at both ends of the first sleeve 21. They are used to press the sealing ring 23 and a group of expansion rings 22 in the end hole section against the annular stepped surface. The pressing assembly includes a second sleeve 24, a screw 25 and a nut 26. The front end of the second sleeve 24 is inserted into the end hole section of the first sleeve 21. Its front end face contacts the end face of the sealing ring 23. A flange plate B 241 is welded on the end face at the rear end of the second sleeve 24. Through holes for the rods are provided on the flange plate B 241 at positions corresponding to and having the same number as the threaded holes on the flange plate A 213. The numbers of the screws 25 and the nuts 26 are both the same as the number of the through holes for the rods on the flange plate B 241. All the screws 25 respectively pass through the respective through holes on the second sleeve 24 and are screwed into the threaded holes at the corresponding positions of the first sleeve 21. A plurality of nuts 26 are respectively threadedly connected to the respective screws 25 and are all abutted against the flange plate B 241. By adjusting the nuts 26, the front end of the second sleeve 24 presses the sealing ring 23 and a group of expansion rings 22 in the end hole section against the annular stepped surface.

[0047] The intermediate frequency melting furnace 3 is arranged in the inner cavity of the vacuum chamber 1. The upper end of the intermediate frequency melting furnace 3 is provided with an open mouth 31, the lower end is provided with a water outlet 32, and the bottom is provided with an installation opening. The open mouth 31 of the intermediate frequency melting furnace 3 is open in the inner cavity of the vacuum chamber 1.

[0048] The crystallizer 4 is arranged in the inner cavity of the vacuum chamber 1. An inlet and an outlet are respectively arranged at both ends of the crystallizer 4. The inlet of the crystallizer 4 is communicated with the water outlet of the intermediate frequency melting furnace 3. The crystallizer 4 is a water-cooled horizontal continuous casting crystallizer.

[0049] The billet drawing machine 5 is arranged outside the vacuum chamber 1. An ingot guide is arranged at one end of the billet drawing machine 5. The axis line of the ingot guide coincides with the axis line of the inner hole of the vacuum lock 2, and the ingot guide is opposite to the outlet of the crystallizer 4 for pulling out the cast billet.

[0050] The bottom gas blowing device is installed on the installation port of the intermediate frequency melting furnace for blowing inert gas into the inner cavity of the intermediate frequency melting furnace. The bottom gas blowing device includes a porous plug 61, a steel pipe 62 and an inlet pipe A63. The porous plug 61 is hermetically and fixedly installed in the installation port of the intermediate frequency melting furnace 3. The porous plug has the characteristics of isolating molten steel and permeating gas. The upper end of the porous plug is located in the inner cavity of the intermediate frequency melting furnace, and the lower end of the porous plug is located outside the intermediate frequency melting furnace. The upper port of the steel pipe 62 is fixedly connected to the lower end of the porous plug 61. One end of the inlet pipe A61 is connected to the lower port of the steel pipe 62, and the other end is communicated with the gas source for providing inert gas.

[0051] The inner hole gas injection device is connected to the gas injection port 21 of the vacuum lock 2 for injecting inert gas into the inner hole of the vacuum lock 2. The inner hole gas injection device includes an exhaust pipe 71 and an inlet pipe B72. One end of the exhaust pipe 71 is hermetically and fixedly installed on the exhaust hole 212 of the vacuum lock 2, and the other end is communicated with the atmosphere; one end of the inlet pipe B72 is hermetically and fixedly installed on the gas injection hole 211 of the vacuum lock 2, and the other end is communicated with the gas source for providing inert gas.

[0052] Preferably, the material of the vacuum lock 2 is a composite material with expanded graphite (flexible graphite) as the main body, supplemented by metal wires or ceramic fibers to enhance the mechanical strength and wear resistance. The metal wires (stainless steel wires or nickel-based alloy wires) are embedded in the expanded graphite base material in the form of spiral winding or weaving. The metal wires form a framework structure to provide tensile strength and compressive capacity, and the expanded graphite fills the voids and undertakes the sealing function. The ceramic fibers (aluminum oxide or silicon carbide fibers) are mixed into the expanded graphite matrix in the form of short cut fibers, or woven into a mesh layer and alternately laminated with graphite. The ceramic fibers are combined with the expanded graphite base material through mechanical interlocking and high-temperature sintering.

[0053] The following events occur during the dummy bar drawing process in step S02: First, during the process of the dummy bar passing through the inner hole of the first sleeve 21, a seal is formed between the inner hole of the dummy bar and the inner holes of the two sealing rings 23. Then, after the billet enters the inner hole of the first sleeve 21, the part of the sealing ring that interferes with the billet (i.e., the circumference of the central hole of the sealing ring) is burned and vaporized by the high temperature of the billet. The billet transfers heat to the expansion ring 22, causing the expansion ring 22 to expand due to heat and the inner hole size to shrink. After the inner hole size of the expansion ring 23 shrinks, it fits the outer diameter size of the billet to ensure the dynamic sealing effect during the billet drawing process. Moreover, since the expansion ring 22 is compressed by the pressing component in the thickness direction (axial direction) and there is no expansion margin left, the expansion ring 22 can only expand in the radial direction, making the shrinkage amplitude of the inner hole size of the expansion ring 22 even greater.

[0054] Verification of the technical effects of the present invention: Take a sample of the molten steel when step S01 is completed, detect the contents of O, N, H, and S elements, and compare the detection results with the contents of O, N, H, and S elements in the raw materials. The comparison results show that this process can effectively remove the gas elements and S element in the raw materials.

[0055] Conduct creep life, room temperature tensile, and 800°C tensile tests on the semi-finished high-temperature alloy welding wire obtained when step S02 is completed. Conduct creep life, room temperature tensile, and 800°C tensile tests on the standard specimen cast by the mold (with the same shape and size as the semi-finished high-temperature alloy welding wire). Compare the test results of the two (specimen 1 is the control specimen cast by the mold, and specimen 2 is the semi-finished high-temperature alloy welding wire). The comparison results show that the billet produced by this process has good mechanical properties and creep life.

Claims

1. A short process high temperature alloy welding wire manufacturing method, characterized by: steps as follows: S01, frequency melting in vacuum environment: A. Raw material feeding and vacuuming: Firstly, the high temperature alloy raw material and carbon for deoxidation are put into the medium frequency melting furnace, and then the inner cavity of the vacuum chamber where the medium frequency melting furnace is located is vacuumed; B. Melting: Start the medium frequency melting furnace and gradually increase the power to the melting temperature in a step-by-step manner. The melting process should last at least 190 minutes, and ensure that the alloy material is fully liquefied within the first 40 minutes of the melting process. C. Refining: Adjust the power of the medium frequency melting furnace to make the molten steel reach the preset refining temperature; then perform the following operations simultaneously: ①. Keep warm for at least 15 minutes to further discharge the oxygen, nitrogen, hydrogen and sulfur elements in the molten steel; ②. Blow inert gas into the bottom of the inner cavity of the medium frequency melting furnace through the bottom blowing device. The bubbles generated absorb the precipitated gas during the floating process. When the bubbles reach the surface of the molten steel, they are discharged into the inner cavity of the vacuum chamber and are vacuumed away; S02, inert gas protection horizontal continuous casting: Adjust the power of the medium frequency melting furnace, and stop vacuuming after the temperature of the molten steel reaches the casting start temperature, and perform the following operations at the same time: ①. Keep blowing inert gas at the bottom to cover the surface of the molten steel with protective gas; ②. The refined molten steel is discharged from the water outlet of the medium frequency melting furnace, and the molten steel flows into the inside of the crystallizer to form the shell of the ingot; the ingot drawing machine located outside the vacuum chamber drives the ingot rod to move horizontally, and the ingot is continuously pulled out from the inside of the crystallizer to the outside of the vacuum chamber; the pulled ingot is cut into the required length to obtain the semi-finished high-temperature alloy welding wire; S03, post-processing: The semi-finished high-temperature alloy welding wire is peeled on a lathe to remove surface defects on its outer cylindrical surface; then it is prepared into a wire rod that meets the subsequent drawing requirements through a hot rolling process; the wire rod is successively subjected to solution treatment, pickling, rough drawing and fine drawing processes to gradually reduce the diameter of the welding wire to the process requirements, thus obtaining a finished high-temperature alloy welding wire.

2. The short process high temperature alloy welding wire manufacturing method according to claim 1, characterized in that: In step S02, the operations performed simultaneously also include: ③. The ingot guide rod and the billet are respectively passed through the vacuum lock on the outer wall of the vacuum chamber, and inert gas is injected into the inner hole of the vacuum lock through the inner hole gas injection device to prevent external air from entering the inner cavity of the vacuum chamber through the gap between the ingot guide rod and the vacuum lock or the billet and the vacuum lock.

3. The short process high temperature alloy welding wire manufacturing method according to claim 2, characterized in that: In step S02, one end of the initial position of the dummy rod is located outside the vacuum chamber, and the other end passes through the vacuum lock and is located in the inner cavity of the vacuum chamber and extends into the crystallizer; during the horizontal continuous casting process, one end of the billet passes through the vacuum lock and is located in the inner cavity of the vacuum chamber, and the other end is located outside the vacuum chamber; when the dummy rod moves in the vacuum lock, an annular sealing surface is formed between the dummy rod and the vacuum lock, and when the billet moves through the vacuum lock, an annular sealing surface is formed between the billet and the vacuum lock.

4. The short process high temperature alloy welding wire manufacturing method according to claim 3, characterized in that: In step S01, the carbon used for deoxidation is carbon powder, and the added amount thereof is 0.015%-0.025% of the weight of the high-temperature alloy raw material.

5. The short process high temperature alloy welding wire manufacturing method according to claim 4, characterized in that: In step S01, the vacuum degree in the inner cavity of the vacuum chamber is maintained below 10 Pa by evacuating the vacuum chamber.

6. The short process high temperature alloy welding wire manufacturing method according to claim 5, characterized in that: In steps S01-S02, the inert gas is argon with a purity of more than 99.99%, krypton with a purity of more than 99.99%, or helium with a purity of more than 99.99%; in steps S01-S02, the amount of bottom-blown inert gas is based on the fluctuation of the molten steel level and the lack of leakage of the molten steel.

7. A short-process high-temperature alloy welding wire manufacturing system, which is used in conjunction with the short-process high-temperature alloy welding wire manufacturing method according to any one of claims 1 to 6, characterized in that: It includes a vacuum chamber, a vacuum lock, a medium frequency melting furnace, a crystallizer, a casting machine, a bottom blowing device and an inner hole gas injection device; The vacuum chamber comprises a chamber body with an open upper end and an upper cover sealed and installed at the upper open end of the chamber body. The chamber body is provided with an inner cavity for accommodating the medium frequency melting furnace and the crystallizer. The chamber body is provided with a negative pressure exhaust port connected to the inner cavity. The upper cover is provided with an operation port for adding materials and measuring temperature and sampling. A balancing valve is provided inside the operation port. The vacuum lock is fixedly mounted on the side wall of the vacuum chamber, and is provided with an inner hole for the casting billet and the dummy rod to pass through in a sealed manner, and the two ends of the inner hole are respectively connected to the inner cavity of the vacuum chamber and the outside of the vacuum chamber, and the outside is provided with an air injection hole connected to the inner hole and an exhaust hole connected to the inner hole; The medium frequency melting furnace is arranged in the inner cavity of the vacuum chamber, the upper end of the medium frequency melting furnace is provided with an opening, the lower end is provided with a water outlet, the bottom is provided with a mounting opening, and the opening of the medium frequency melting furnace is open in the inner cavity of the vacuum chamber; The crystallizer is arranged in the inner cavity of the vacuum chamber, and an inlet and an outlet are respectively arranged at both ends of the crystallizer, and the inlet of the crystallizer is connected with the water inlet of the medium frequency smelting furnace; the crystallizer is a water-cooled horizontal continuous casting crystallizer; The billet drawing machine is arranged outside the vacuum chamber. A dummy bar is arranged at one end of the billet drawing machine. The axis of the dummy bar coincides with the axis of the inner hole of the vacuum lock. The dummy bar faces the outlet of the crystallizer and is used to pull out the billet. The bottom blowing device is installed on the installation port of the medium frequency melting furnace and is used to blow inert gas into the inner cavity of the medium frequency melting furnace; The inner hole gas injection device is connected to the gas injection port of the vacuum lock and is used for injecting inert gas into the inner hole of the vacuum lock.

8. The short process high temperature alloy welding wire manufacturing system as claimed in claim 7, characterized in that: The bottom blowing device includes a breathable brick, a steel pipe and an air inlet pipe A; the breathable brick is sealed and fixedly installed in the installation port of the medium frequency melting furnace, the breathable brick has the characteristics of isolating molten steel and being breathable, the upper end of the breathable brick is located in the inner cavity of the medium frequency melting furnace, and the lower end of the breathable brick is located outside the medium frequency melting furnace; the upper end of the steel pipe is fixedly connected to the lower end of the breathable brick; one end of the air inlet pipe A is connected to the lower end of the steel pipe, and the other end is connected to a gas source for providing inert gas.

9. The short process high temperature alloy welding wire manufacturing system as claimed in claim 8, characterized in that: The inner hole gas injection device includes an exhaust pipe and an air inlet pipe B; one end of the exhaust pipe is sealed and fixedly installed on the exhaust hole of the vacuum lock, and the other end is connected to the atmosphere; one end of the air inlet pipe B is sealed and fixedly installed on the air injection hole of the vacuum lock, and the other end is connected to a gas source for providing inert gas.

10. The short process high temperature alloy welding wire manufacturing system according to claim 9, characterized in that: The vacuum lock includes a first sleeve, an expansion ring, a sealing ring and a clamping assembly; the first sleeve is in the shape of a sleeve with two ends open, and its inner hole includes a middle hole section and end hole sections arranged on both sides of the middle hole section, and an annular step surface is respectively provided between the middle hole section and the two end hole sections, and the aperture of the middle hole section is smaller than the two end hole sections, and the outer surface of the first sleeve is provided with the injection hole connected to the middle hole section and the exhaust hole connected to the middle hole section, and flanges A are respectively welded on the two end surfaces of the first sleeve, and the flange A is provided with a plurality of threaded holes evenly distributed in an annular shape; at least three expansion rings are stacked with their end faces to form a group, and the two groups of expansion rings are respectively installed in the two end hole sections of the first sleeve, and the inner holes of all the expansion rings in each group of expansion rings are connected in sequence to form a casting blank sealing section; two sealing rings are respectively installed in the two end hole sections of the first sleeve, and the end faces of the sealing rings are in contact with the outermost expansion rings in the end hole sections, and the sealing rings The inner hole forms a sealing section for the dummy rod; two sets of clamping assemblies are respectively installed in the end hole sections at both ends of the first sleeve, which are used to clamp the sealing ring and a group of expansion rings in the end hole sections onto the annular step surface; the clamping assembly includes a second sleeve, a screw and a nut; the front end of the second sleeve is inserted into the end hole section of the first sleeve, and the end face of its front end contacts the end face of the sealing ring, and a flange B is welded on the end face of the rear end of the second sleeve, and the flange B is provided with through-rod holes corresponding to the positions of the threaded holes on the flange A and the same number; the number of screws and nuts is consistent with the number of through-rod holes on the flange B; all the screws pass through the through-rod holes on the second sleeve respectively and are screwed into the threaded holes at the corresponding positions of the first sleeve, and a plurality of nuts are respectively threadedly connected to the screws and abut against the flange B; the front end of the second sleeve is adjusted to compress the sealing ring and a group of expansion rings in the end hole section onto the annular step surface.

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