Electroslag welding device and welding method thereof

Abstract

The invention provides an electroslag welding device and a welding method thereof.The electroslag welding device comprises a workpiece body and a power source, a slag pool is arranged in the workpiece body, a molten pool is arranged below the slag pool, and metal slag in the slag pool is accumulated below the molten pool to form a welding seam after passing through the molten pool; a liquid cooling forming sliding block is arranged on the periphery of the molten pool; wherein the height of the molten pool is increased along with accumulation of the weld joints, and the height of the liquid cooling forming sliding block is increased along with the molten pool; moreover, a first conductive path is arranged between the slag bath and the positive electrode of the power supply, a second conductive path is arranged between the welding seam and the negative electrode of the power supply, and a third conductive path is arranged between the liquid cooling forming sliding block and the negative electrode. According to the electroslag welding device, the problem that in the prior art, the welding seam forming quality is poor can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of building construction, and more specifically, to an electroslag welding device and a welding method thereof. Background Art

[0002] Traditional electroslag welding has only one current loop, and its current path is power supply-melting nozzle steel pipe-slag pool-metal molten pool-weld-workpiece-power supply. Generally, in order to ensure the surface quality of electroslag welding welds, a larger current and a higher melting rate are required for smelting; this method will cause the metal molten pool to become deeper, and the liquid-cooled forming slider has limited cooling capacity for the center of the weld, which can easily increase the local solidification time at the solidification front of the weld, accelerate the rising speed of the slag pool, and shorten the heat diffusion time. At the same time, it will cause defects such as unfusion and slag inclusion, resulting in insufficient melting of the edge of the parent material and an unformed weld.

[0003] On the contrary, if a smaller current and a lower melting rate are used, although a shallower molten pool can be obtained and the degree of component segregation in the weld can be reduced, it is easy to cause insufficient melting of the slag skin on the liquid-cooled forming slider, making the slag skin thicker and even causing slag grooves, ripples and other weld surface quality defects.

[0004] Based on the above technical problems, there is an urgent need for a solution that can ensure both the weld formation and the weld surface and internal quality. Summary of the invention

[0005] In view of the above problems, an object of the present invention is to provide an electroslag welding device and a welding method thereof to solve the problem of poor weld forming quality in the prior art.

[0006] The present invention provides an electroslag welding device, comprising a workpiece body and a power source, wherein a slag pool is arranged in the workpiece body, a molten pool is arranged below the slag pool, metal slag in the slag pool accumulates below the molten pool to form a weld after passing through the molten pool, and a liquid-cooled forming slider is arranged at the periphery of the molten pool; wherein the height of the molten pool increases with the accumulation of the weld, and the height of the liquid-cooled forming slider increases with the molten pool; and,

[0007] A first conductive path is provided between the slag pool and the positive electrode of the power supply, a second conductive path is provided between the weld and the negative electrode of the power supply, and a third conductive path is provided between the liquid-cooled forming slider and the negative electrode.

[0008] In addition, a preferred solution is that a first switch is provided on the first conductive path, a second switch is provided on the second conductive path, and a third switch is provided on the third conductive path.

[0009] In addition, a preferred solution is that a first ammeter is provided on the first conductive path, a second ammeter is provided on the second conductive path, and a third ammeter is provided on the third conductive path.

[0010] In addition, a preferred solution is that a circulating coolant is installed in the liquid-cooled forming slider; and,

[0011] A liquid inlet and a liquid outlet are provided on the liquid-cooled forming slider, and the liquid-cooled forming slider is connected to an external liquid supply device through the liquid inlet and the liquid outlet.

[0012] In addition, a preferred solution is that an adjustable resistor connected between the molten pool and the third conductive path is provided in the liquid-cooled forming slide.

[0013] In addition, a preferred solution is that the circulating coolant forms the adjustable resistor; and,

[0014] The volume and flow rate of the circulating coolant are adjusted by the liquid supply device in cooperation with the liquid inlet and the liquid outlet to adjust the resistance value of the adjustable resistor.

[0015] In addition, a preferred solution is that a nozzle pipe is provided in the slag hole of the slag pool, and the slag pool is connected to the first conductive path through the nozzle pipe.

[0016] In addition, a preferred solution is that a welding wire is arranged in the nozzle tube.

[0017] In addition, a preferred solution is that a welding groove is provided at the bottom of the workpiece body, and the weld is accumulated and formed in the welding groove.

[0018] On the other hand, the present invention also provides a welding method of the aforementioned electroslag welding device, the welding method comprising:

[0019] Turn on the power supply, close the first switch and the second switch, and after the arc is energized and slag is formed, the weld begins to form in the welding groove, the molten pool begins to rise with the accumulation of the weld, and the liquid-cooled forming slider begins to move upward with the molten pool;

[0020] The third switch is closed to form a first loop and a second loop; wherein the first loop sequentially includes the positive electrode of the power supply, the first conductive path, the nozzle tube, the slag pool, the molten pool, the weld, the welding groove, the second conductive path, and the negative electrode of the power supply; the second loop sequentially includes the positive electrode of the power supply, the first conductive path, the nozzle tube, the slag pool, the molten pool, the liquid-cooled forming slider, the second conductive path, and the negative electrode of the power supply;

[0021] The adjustable resistance of the liquid-cooled forming slider is adjusted to adjust the current and power ratio values ​​of the first circuit and the second circuit to follow the corresponding preset ratio values ​​until the welding is completed.

[0022] Compared with the prior art, the electroslag welding device and the welding method provided by the present invention, by adding a new current circuit (the second circuit, the second circuit sequentially includes the positive electrode of the power supply, the first conductive path, the nozzle tube, the slag pool, the molten pool, the liquid-cooled forming slider, the second conductive path, and the negative electrode of the power supply), can, during the actual welding process, adjust the current and power ratio values ​​of the first circuit and the second circuit so that the current and power ratio values ​​of the first circuit and the second circuit follow the corresponding preset ratio values, thereby optimizing the temperature distribution of heat in the molten pool and the slag pool, achieving uniform distribution of heat and temperature, and effectively improving the forming quality of the electroslag welding weld.

[0023] In order to achieve the above and related purposes, one or more aspects of the present invention include features that will be described in detail later and are particularly pointed out in the claims. The following description and the accompanying drawings describe some exemplary aspects of the present invention in detail. However, these aspects indicate only some of the various ways in which the principles of the present invention can be used. In addition, the present invention is intended to include all of these aspects and their equivalents. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] By referring to the following description and claims in conjunction with the accompanying drawings, and with a more comprehensive understanding of the present invention, other objects and results of the present invention will become more apparent and easier to understand. In the accompanying drawings:

[0025] Figure 1 is a structural principle diagram of an electroslag welding device provided by an embodiment of the present invention;

[0026] In the figure, welding wire 1, nozzle tube 2, workpiece body 3, liquid outlet 4, slag pool 5, molten pool 6, weld 7, welding groove 8, second conductive path 9, third conductive path 10, power supply 11, first conductive path 12, liquid-cooled forming slider 13, and liquid inlet 14.

[0027] The same reference numerals throughout the drawings indicate similar or corresponding features or functions. DETAILED DESCRIPTION

[0028] In the following description, for the purpose of illustration, in order to provide a comprehensive understanding of one or more embodiments, many specific details are set forth. However, it is apparent that these embodiments may also be implemented without these specific details. In other examples, for ease of describing one or more embodiments, known structures and devices are shown in the form of block diagrams.

[0029] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention; the terms "first", "second", and "third" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance; in addition, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] Figure 1 The structural principle of the electroslag welding device provided by the embodiment of the present invention is shown. Figure 1 It can be known that the electroslag welding device provided by the present invention includes a workpiece body 3 as the main body of the electroslag welding device and a power supply 11 for supplying power to the entire electroslag welding device.

[0031] Specifically, a slag pool 5 is provided in the workpiece body 3, and metal slag is contained in the slag pool 5. A molten pool 6 (metal molten pool 6) is provided below the slag pool 5. The metal slag in the slag pool 5 accumulates below the molten pool 6 to form a solid weld 7 after passing through the molten pool 6, and a liquid-cooled forming slider 13 is provided on the periphery of the molten pool 6. The molten metal slag flowing out of the molten pool 6 is cooled and formed by the liquid-cooled forming slider 13, and it is ensured that the welding gun guide tube is not overheated so that the molten metal slag forms a solid weld 7. It should be noted that the heights of the slag pool 5 and the molten pool 6 (the slag pool 5 and the molten pool 6 move synchronously) increase with the accumulation of the solid weld 7, and the height of the liquid-cooled forming slider 13 increases with the molten pool 6 (the liquid-cooled forming slider 13 moves upward driven by the slag pool 5 and the molten pool 6).

[0032] In order to improve the forming quality of the electroslag welding weld 7, a first conductive path 12 is arranged between the slag pool 5 and the positive pole of the power supply 11, a second conductive path 9 is arranged between the weld 7 and the negative pole of the power supply 11 (this path corresponds to the partial structure of the loop in the existing scheme), and a third conductive path 10 is arranged between the liquid-cooled forming slider 13 and the negative pole (this path corresponds to the partial structure of the newly added second loop provided by the present invention).

[0033] The electroslag welding device provided by the present invention, by newly adding a current circuit (second circuit), can, during the actual welding process, adjust the current and power ratio values ​​between the first circuit and the second circuit so that the current and power ratio values ​​between the first circuit and the second circuit follow the corresponding preset ratio values, thereby optimizing the temperature distribution of heat in the molten pool 6 and the slag pool 5, achieving uniform distribution of heat and temperature, and effectively improving the forming quality of the electroslag welding weld 7.

[0034] In addition, in order to realize switch control of each path, a first switch (not marked in the figure) is provided on the first conductive path 12, a second switch (not marked in the figure) is provided on the second conductive path 9, and a third switch (not marked in the figure) is provided on the third conductive path 10; and, in order to facilitate the observation of the current flowing through each path, a first ammeter (not marked in the figure) is provided on the first conductive path 12, a second ammeter (not marked in the figure) is provided on the second conductive path 9, and a third ammeter (not marked in the figure) is provided on the third conductive path 10.

[0035] In a specific embodiment of the present invention, in order to realize cooling and molding of molten metal slag by the liquid-cooled molding slider 13, a circulating coolant is installed in the liquid-cooled molding slider 13; and a liquid inlet 14 and a liquid outlet 4 are provided on the liquid-cooled molding slider 13, and the liquid-cooled molding slider 13 is connected to an external liquid supply device through the liquid inlet 14 and the liquid outlet 4, and the circulating coolant in the liquid-cooled molding slider 13 is circulated and cooled through the liquid supply device in cooperation with the liquid inlet 14 and the liquid outlet 4.

[0036] Furthermore, in order to adjust the ratio of the current and power between the first circuit and the second circuit, an adjustable resistor connected between the molten pool 6 and the third conductive path 10 is provided in the liquid-cooled forming slider 13. By adjusting the access resistance of the adjustable resistor, the ratio of the current and power between the first circuit and the second circuit can be adjusted.

[0037] In a preferred embodiment of the present invention, the adjustable resistor can be formed by the circulating coolant; the volume and flow rate of the circulating coolant are adjusted by the liquid supply device in cooperation with the liquid inlet 14 and the liquid outlet 4, and then the resistance of the circulating coolant in the liquid-cooled forming slider 13 is adjusted to achieve the adjustment of the resistance value of the adjustable resistor.

[0038] In addition, in order to realize the arc starting and slag forming of the electroslag welding device provided by the present invention, a nozzle tube 2 (i.e., an externally coated tube welding rod) can be arranged in the unobstructed slag hole in the middle of the slag pool 5, and the slag pool 5 is connected to the first conductive path 12 through the nozzle tube 2; and, a welding wire 1 is arranged in the nozzle tube 2, and the welding wire 1 passes through the externally coated tube welding rod) as a melting electrode, and the welding wire 1 cooperates with the externally coated tube welding rod to realize the arc starting and slag forming of the electroslag welding device provided by the present invention.

[0039] In addition, in order to facilitate the collection of the weld 7 in the workpiece body 3, a welding groove 8 can be provided at the bottom of the workpiece body 3, and the weld 7 is accumulated and formed in the welding groove 8 and rises until it enters the interior of the workpiece body 3 (such as Figure 1 shown).

[0040] On the other hand, in order to facilitate understanding of the working principle of the electroslag welding device provided by the present invention, the present invention also provides a welding method of the electroslag welding device, the welding method comprising:

[0041] The power supply 11 is turned on, and the first switch and the second switch are closed. After the arc is energized and slag is formed, the weld 7 begins to form in the welding groove 8, and the molten pool 6 begins to rise with the accumulation of the weld 7, and the liquid-cooled forming slider 13 begins to move upward with the molten pool 6;

[0042] The third switch is closed to form a first loop and a second loop; wherein the first loop sequentially includes the positive electrode of the power supply 11, the first conductive path 12, the nozzle tube 2, the slag pool 5, the molten pool 6, the weld 7, the welding groove 8, the second conductive path 9, and the negative electrode of the power supply 11; the second loop sequentially includes the positive electrode of the power supply 11, the first conductive path 12, the nozzle tube 2, the slag pool 5, the molten pool 6, the liquid-cooled forming slider 13, the second conductive path 9, and the negative electrode of the power supply 11;

[0043] The adjustable resistance of the liquid-cooled forming slider 13 is adjusted to adjust the current and power ratio values ​​of the first circuit and the second circuit to follow the corresponding preset ratio values ​​until the welding is completed.

[0044] It should be noted that, for the first circuit, as the height of the weld 7 continues to increase, the resistance connected to the first circuit will continue to increase (the resistance connected to the first circuit includes the resistance of the weld 7, the resistance of the welding groove 8, the resistance of the molten pool 6, the resistance of the slag pool 5, etc., among which, only the resistance of the weld 7 will continue to increase), resulting in the current and power of the first circuit constantly changing; for the second circuit, the resistance connected to the second circuit is adjusted by adjusting the resistance value of the adjustable resistor (the resistance connected to the second circuit includes the resistance of the molten pool 6, the resistance of the slag pool 5, the adjustable resistance of the liquid-cooled forming slider 13, etc., among which, only the resistance value of the adjustable resistor of the liquid-cooled forming slider 13 will be adjustable) to adjust the current of the second circuit, thereby balancing the current and power of the first circuit and the second circuit, so that the ratio values ​​of the current and power of the first circuit and the second circuit follow the corresponding preset ratio values.

[0045] In addition, it should be noted that the specific setting of the above-mentioned preset ratio (which may be a dynamic value) and how to adjust the adjustable resistance of the liquid-cooled forming slider 13 to achieve that the current and power ratio values ​​of the first circuit and the second circuit follow the corresponding preset ratio values ​​are all related to the parameters of the various components of the device in the actual production process. After the parameters of the various components of the device are determined, the specific setting of the preset ratio (which may be a dynamic value) and the specific adjustment method of adjusting the adjustable resistance of the liquid-cooled forming slider 13 to achieve that the current and power ratio values ​​of the first circuit and the second circuit follow the corresponding preset ratio values ​​can be determined through a large number of experiments; the innovation of the present invention is that by setting the second circuit and the adjustable resistance, the forming quality of the electroslag welding weld 7 can be improved. Therefore, the specific setting of the above-mentioned preset ratio (which may be a dynamic value) and how to adjust the adjustable resistance of the liquid-cooled forming slider 13 to achieve that the current and power ratio values ​​of the first circuit and the second circuit follow the corresponding preset ratio values ​​will not be repeated here.

[0046] As above Figure 1 The electroslag welding device and the welding method according to the present invention are described in an exemplary manner. However, those skilled in the art should understand that various improvements can be made to the electroslag welding device and the welding method proposed by the present invention without departing from the content of the present invention. Therefore, the protection scope of the present invention should be determined by the content of the attached claims.

Claims

1. An electroslag welding device, characterized in that: The invention comprises a workpiece body and a power source, wherein a slag pool is arranged in the workpiece body, a molten pool is arranged below the slag pool, metal slag in the slag pool accumulates below the molten pool to form a weld after passing through the molten pool, and a liquid-cooled forming slider is arranged at the periphery of the molten pool; wherein the height of the molten pool increases with the accumulation of the weld, and the height of the liquid-cooled forming slider increases with the molten pool; and, A first conductive path is provided between the slag pool and the positive electrode of the power supply, a second conductive path is provided between the weld and the negative electrode of the power supply, and a third conductive path is provided between the liquid-cooled forming slider and the negative electrode.

2. The electroslag welding device according to claim 1, characterized in that: A first switch is provided on the first conductive path, a second switch is provided on the second conductive path, and a third switch is provided on the third conductive path.

3. The electroslag welding device according to claim 2, characterized in that: A first ammeter is provided on the first conductive path, a second ammeter is provided on the second conductive path, and a third ammeter is provided on the third conductive path.

4. The electroslag welding device according to claim 3, characterized in that: A circulating coolant is installed in the liquid-cooled forming slide block; and, A liquid inlet and a liquid outlet are provided on the liquid-cooled forming slider, and the liquid-cooled forming slider is connected to an external liquid supply device through the liquid inlet and the liquid outlet.

5. The electroslag welding device according to claim 4, characterized in that: An adjustable resistor connected between the molten pool and the third conductive path is arranged in the liquid-cooled forming slide block.

6. The electroslag welding device according to claim 5, characterized in that: The circulating coolant forms the adjustable resistor; and, The volume and flow rate of the circulating coolant are adjusted by the liquid supply device in cooperation with the liquid inlet and the liquid outlet to adjust the resistance value of the adjustable resistor.

7. The electroslag welding device according to claim 1, characterized in that: A nozzle pipe is arranged in the slag hole of the slag pool, and the slag pool is connected to the first conductive path through the nozzle pipe.

8. The electroslag welding device according to claim 7, characterized in that: A welding wire is arranged in the nozzle tube.

9. The electroslag welding device according to claim 1, characterized in that: A welding groove is arranged at the bottom of the workpiece body, and the weld is accumulated and formed in the welding groove.

10. A welding method using the electroslag welding device according to any one of claims 1 to 9, characterized in that: The welding method comprises: Turn on the power supply, close the first switch and the second switch, and after the arc is energized and slag is formed, the weld begins to form in the welding groove, the molten pool begins to rise with the accumulation of the weld, and the liquid-cooled forming slider begins to move upward with the molten pool; The third switch is closed to form a first loop and a second loop; wherein the first loop sequentially includes the positive electrode of the power supply, the first conductive path, the nozzle tube, the slag pool, the molten pool, the weld, the welding groove, the second conductive path, and the negative electrode of the power supply; the second loop sequentially includes the positive electrode of the power supply, the first conductive path, the nozzle tube, the slag pool, the molten pool, the liquid-cooled forming slider, the second conductive path, and the negative electrode of the power supply; The adjustable resistance of the liquid-cooled forming slider is adjusted to adjust the current, voltage and power ratio values ​​of the first circuit and the second circuit to follow the corresponding preset ratio values ​​until the welding is completed.

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