A continuous welding device and welding process for a petrochemical hydrogenation reactor

Abstract

This invention relates to the field of submerged arc welding equipment technology, specifically providing a continuous welding device and welding process for a petrochemical hydrogenation reactor. The device includes a worktable on which a circular workpiece is rotatably mounted. A moving platform is located on one side of the worktable, and a welding head is movably mounted on the moving platform. The welding head contains two parallel welding strips, a first welding strip and a second welding strip, replacing the traditional wide welding strip. The first welding strip is fed at a slower speed than the second welding strip. This addresses the characteristic of high outer linear velocity and slow inner linear velocity during welding of a circular workpiece. The slower inner welding strip feeding reduces inner molten pool buildup, while the faster outer welding strip feeding replenishes material in the outer molten pool, resulting in a more uniform radial thickness of the molten pool. Furthermore, the narrower width of the first and second welding strips allows for a more uniform current distribution on either strip, significantly reducing magnetic blow, arc deviation, and the incidence of defects such as undercut, thus improving the welding quality.

Description

Technical Field

[0001] This invention relates to the field of submerged arc welding equipment technology, and in particular to a continuous welding device and welding process for a petrochemical hydrogenation reactor. Background Technology

[0002] Hardfacing equipment is a specialized piece of equipment for hardfacing workpieces. Its core function is to fuse the welding strip (or other welding materials) with the base material to form a weld layer on the workpiece surface that meets the requirements of wear resistance and corrosion resistance. It is widely used in the manufacture and repair of workpieces such as end caps of hydrogenation reactors, valves, and molds.

[0003] For example, Chinese patent CN115815744A discloses an automatic electrode-mounted welding equipment for end caps. The solution includes a worktable for clamping products, a rotating base, a column vertically connected to the rotating base at its lower end, a crossbeam horizontally connected to the column, and a welding machine body set at the end of the crossbeam. The crossbeam can move up and down relative to the column and can also extend and retract laterally relative to the column. The worktable can rotate and flip about a certain horizontal axis. This solution sets the welding machine body at the end of the crossbeam, aligns the welding body with the workpiece, and the worktable rotates to continuously build up the weld.

[0004] However, when the aforementioned welding equipment processes round workpieces, especially when welding on the surface of round workpieces, such as welding the end cap of a round hydrogenation reactor, the welding head needs to make a circular motion relative to the end cap. In order to ensure processing efficiency, a wider welding strip is generally used. However, the linear velocity of the inner and outer sides of the wider welding strip is different on the radial direction of the end cap during welding. Especially when using a wide welding strip to weld a small diameter, the speed difference between the inner and outer sides of the welding strip is even greater. This can easily lead to a thinner weld on the outer side of the molten pool due to the faster speed, and a thicker weld on the inner side due to the faster speed, thus affecting the welding quality. Summary of the Invention

[0005] Therefore, it is necessary to provide a continuous welding device and welding process for a petrochemical hydrogenation reactor to address the problem of poor welding quality of current welding equipment when welding circular workpieces.

[0006] The above objectives are achieved through the following technical solutions: A continuous welding apparatus for a petrochemical hydrogenation reactor, comprising: A frame, on which a worktable is provided, and a circular workpiece is rotatably connected to the worktable; A mobile platform is located close to the frame. A support arm is vertically fixed on the mobile platform, and a cantilever extending laterally is vertically slidably mounted on the support arm. The welding body is laterally slidably mounted on the cantilever. The welding body includes a welding head and a material conveying bin. The welding head conveys two parallel and relatively sliding first and second welding strips. The first welding strip is located inside the second welding strip and the conveying speed of the first welding strip is less than that of the second welding strip. The material conveying bin is filled with flux. The flux is discharged from the outer periphery of the welding head and falls onto a circular workpiece to cover the electric arc.

[0007] Furthermore, the welding head is provided with a first roll and a second roll, the axes of the first roll and the second roll are parallel to each other, and the end faces of the first roll and the second roll that are close to each other are on the same plane. The first welding strip is wound on the first roll and the second welding strip is wound on the second roll. The welding head is provided with a first drive roller and a second drive roller. There are two first drive rollers that hold the first welding strip and two second drive rollers that hold the second welding strip. The rotation speed of the first drive roller is less than the rotation speed of the second drive roller.

[0008] Furthermore, clamping components are provided on both sides of the first and second welding strips. The clamping components are used to slide and clamp the first and second welding strips so that they are placed side by side. The clamping force of the clamping components on the first and second welding strips is positively correlated with the conveying time of the first and second welding strips.

[0009] Furthermore, the clamping assembly includes multiple elastic top blocks and two inclined plates. The two inclined plates are vertically slidably connected inside the weld head, and the sides of the two inclined plates that are close to each other are inclined surfaces. The multiple elastic top blocks are horizontally slidably disposed on the side where the first weld strip and the second weld strip are far apart from each other. One end of the multiple elastic top blocks makes rolling contact with the side where the first weld strip and the second weld strip are far apart from each other, and the other end of the multiple elastic top blocks slides against the inclined surfaces of the two inclined plates. The two inclined plates are configured to move upward as the first weld strip and the second weld strip are conveyed for longer periods. The two inclined plates push the multiple elastic top blocks toward the first weld strip and the second weld strip.

[0010] Furthermore, the upper ends of the two inclined plates are fixedly connected and equipped with vertically extending racks. The upper end of the welding head is rotatably equipped with a gear that meshes with the rack. A detection rod extending radially along the gear is fixedly installed at the axis of the gear. One end of the detection rod is fixed to the gear, and the other end of the detection rod slides in contact with the top of the first roller on which the first welding strip is wound or the second roller on which the second welding strip is wound. An elastic element is provided at the rotatable connection position between the gear and the welding head. The elastic element causes the detection rod to have a tendency to rotate downward around the rotation center.

[0011] Furthermore, a triangular protrusion is provided on the side of the first welding strip near the second welding strip, and a triangular groove is provided on the side of the second welding strip near the first welding strip, with the triangular protrusion slidingly engaging with the triangular groove.

[0012] Furthermore, the welding head has an inner layer and an outer layer, with a cavity between the inner and outer layers, the cavity being connected to the material conveying bin, and the inner layer of the welding head being used to convey the first welding strip and the second welding strip.

[0013] Furthermore, a collection pipe is provided on one side of the welding head, and the opening of the collection pipe is located on the rear side of the welding head relative to the direction of movement of the circular workpiece.

[0014] Furthermore, a vacuum pump is connected to the collection pipe.

[0015] This invention also provides a continuous welding process for a petrochemical hydrogenation reactor, comprising the following steps: Step S100: Adjust the conveying speed of the first and second welding strips according to the processing parameters of the circular workpiece, so that the conveying speed of the first welding strip is less than the conveying speed of the second welding strip. Step S200: Adjust the first or second welding strip to be close to the surface of the circular workpiece; Step S300: After each round of welding is completed, adjust the welding head to move inward a preset distance along the radial direction of the circular workpiece.

[0016] The beneficial effects of this invention are: This invention replaces the traditional wide welding strip by setting two parallel welding strips, the first and second, inside the welding head. The first welding strip is fed at a slower speed than the second welding strip. This addresses the characteristic of high outer linear velocity and slow inner linear velocity when welding circular workpieces. The slower inner welding strip feeding reduces the accumulation of material in the inner molten pool, while the faster outer welding strip feeding replenishes the material in the outer molten pool, making the molten pool uniform in thickness along the radial direction. This avoids the defect of traditional wide welding strips being thin on the outside and thick on the inside, meeting the high requirement of consistent weld layer thickness for hydrogenation reactor end caps. Furthermore, the narrower width of the first and second welding strips allows for a more uniform current distribution on either the first or second welding strip, significantly reducing magnetic blow, arc deviation, and the incidence of defects such as undercut and irregular weld beads, thus improving the weld quality.

[0017] This invention uses a first welding strip and a second welding strip to adjust the first welding strip or the second welding strip closer to the surface of the circular workpiece before the welding process begins. This makes it easier to initiate the arc when the first welding strip and the second welding strip are used together, avoiding the need to trim the wide welding strip before each welding process in the prior art, and simplifying the welding process.

[0018] This invention provides a clamping component for slidably clamping the first and second welding strips, thereby reducing the gap between the first and second welding strips when they are side by side. At the same time, the triangular protrusion and triangular groove are provided for sliding cooperation to cancel out the forces of the same magnitude but opposite direction on the first and second welding strips, thereby improving the flatness of the first and second welding strips when they are transported. Attached Figure Description

[0019] Figure 1 A schematic diagram of the structure of a continuous welding device for a petrochemical hydrogenation reactor provided in an embodiment of the present invention; Figure 2 for Figure 1 A left view of a continuous welding apparatus for a petrochemical hydrogenation reactor provided in one embodiment; Figure 3 A schematic diagram of the weld head structure of a continuous welding device for a petrochemical hydrogenation reactor provided in an embodiment of the present invention; Figure 4 for Figure 3 A left view of the weld head of a continuous welding apparatus for a petrochemical hydrogenation reactor provided in one embodiment; Figure 5 for Figure 3 A front view of the weld overlay head of a continuous welding apparatus for a petrochemical hydrogenation reactor provided in one embodiment; Figure 6 for Figure 5 A cross-sectional view along AA of the weld overlay head of the continuous welding apparatus for a petrochemical hydrogenation reactor provided in one embodiment. Figure 7 for Figure 5 A cross-sectional view along BB of the weld overlay head of the continuous welding apparatus for a petrochemical hydrogenation reactor provided in one embodiment; Figure 8 for Figure 7 A partially enlarged view of the weld head X portion of the continuous welding apparatus for a petrochemical hydrogenation reactor provided in one embodiment; Figure 9 for Figure 3 A top view of the weld overlay head of a continuous welding apparatus for a petrochemical hydrogenation reactor provided in one embodiment; Figure 10 for Figure 9 A cross-sectional view along CC of the weld overlay head of a continuous welding apparatus for a petrochemical hydrogenation reactor provided in one embodiment. Figure 11 for Figure 10 A partially enlarged view of the weld head Y portion of the continuous welding apparatus for a petrochemical hydrogenation reactor provided in one embodiment; Figure 12This is an exploded view of the weld head of a continuous welding apparatus for a petrochemical hydrogenation reactor according to an embodiment of the present invention.

[0020] in: 100. Frame; 110. Workbench; 120. Rotary disk; 130. Moving platform; 140. Support arm; 150. Cantilever; 200, Welding head; 201, Inner layer; 202, Outer layer; 203, First support; 204, Second support; 210, First welding strip; 211, Triangular protrusion; 220, Second welding strip; 221, Triangular groove; 230, First winding roller; 240, Second winding roller; 250, First drive roller; 260, Second drive roller; 270, First drive motor; 280, Second drive motor; 290, Conveying bin; 300, Inclined plate; 310, Elastic top block; 320, Slide rod; 330, Roller; 340, Compression spring; 350, Rack; 360, Gear; 370, Detection rod; 380, Elastic element; 400. Collection pipe; 410. Vacuum pump; 500. Circular workpiece. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0022] The component designations used in this document, such as "first" and "second," are merely for distinguishing the described objects and do not have any sequential or technical meaning. The terms "connection" and "linkage" used in this invention, unless otherwise specified, include both direct and indirect connections (linkages). It should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are used only for the convenience of describing the invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the invention.

[0023] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0024] The following reference Figures 1-12 This invention describes a continuous welding apparatus for a petrochemical hydrogenation reactor.

[0025] A continuous welding apparatus for a petrochemical hydrogenation reactor, suitable for submerged arc welding of the reactor end cap, includes a frame 100, a worktable 110 mounted on the frame 100, and a rotating disk 120 mounted on the worktable 110. The rotating disk 120 is used to clamp the reactor end cap, which is a circular workpiece 500, and its surface requires submerged arc welding. A movable platform 130 is mounted on one side of the frame 100, with a vertically fixed support arm 140. A horizontally extending cantilever 150 is vertically slidably mounted on the support arm 140, and a welding body is horizontally slidably mounted on the cantilever 150. The welding body is used for submerged arc welding of the inner surface of the reactor end cap. The position of the welding body can be adjusted by the height of the vertically slidable cantilever 150. A drive wheel (not shown in the figure) is mounted at the bottom of the movable platform 130, which can move the movable platform 130 to adjust the horizontal position of the welding body. After the position is adjusted, the welding body and rotating disk 120 are started. The rotating disk 120 rotates relative to the welding body, thereby automatically performing submerged arc welding. The welding body includes a welding head 200 and a material conveying bin 290. The material conveying bin 290 is filled with flux. The flux is discharged from the outer periphery of the welding head 200 and falls onto the circular workpiece 500 (hydrogenation reactor end cover). The welding head 200 is equipped with a welding strip. Due to the large size of the circular workpiece 500, in order to ensure a certain welding efficiency, the welding strip width used in the prior art is relatively wide. However, when the wider welding strip is welded on the surface of the circular workpiece 500, the linear velocity of the welding strip on the inner and outer sides of the circular workpiece 500 along the radial direction is different. Especially when using a wide welding strip to weld a small-diameter circular workpiece 500, the speed difference between the inner and outer sides of the welding strip is even greater. Since the overall conveying speed of a welding strip is the same, it is easy for the outer side of the weld pool generated by the welding strip to be thinner due to the faster speed and the inner side to be thicker due to the slower speed, thus affecting the overall welding quality.

[0026] Based on this, the present invention replaces the wider welding strip in the prior art with two welding strips. The sum of the widths of the two welding strips is the same as the width of the wider welding strip in the prior art. The two welding strips are arranged side by side on the same plane and can slide relative to each other. For ease of description, the welding strip located inside the circular workpiece 500 in the radial direction is named the first welding strip 210, and the welding strip located outside the circular workpiece 500 in the radial direction is named the second welding strip 220. The first welding strip 210 and the second welding strip 220 are conveyed at different speeds within the welding head 200. In order to increase the thickness of the outer molten pool, the second welding strip can be improved. The conveying speed of the first welding strip 220 allows for the conveying of more second welding strips 220 within the same time period, thereby increasing the thickness of the outer molten pool and making the overall thickness of the molten pool uniform. Alternatively, the conveying speed of the first welding strip 210 can be reduced, allowing for the conveying of fewer first welding strips 210 within the same time period, thereby reducing the thickness of the inner molten pool and making the overall thickness of the molten pool similar. In other words, the conveying speed of the first welding strip 210 is less than the conveying speed of the second welding strip 220, thereby reducing the uneven molten pool thickness caused by welding wider welding strips in the prior art, and improving the welding quality as much as possible while ensuring the overall welding efficiency.

[0027] At the same time, it is understandable that when using a wider welding strip for overlay welding in the existing technology, especially when using a welding strip with a width of 60mm or more, the uneven distribution of current on the wide welding strip disrupts the uniformity of the magnetic field around the arc, which in turn causes magnetic blow problem, thus easily leading to problems such as undercut and uneven weld bead.

[0028] Magnetic blow refers to the phenomenon where, during welding, the uniformity of the magnetic field distribution around the electric arc is disrupted due to various reasons, causing the arc to deviate from the center of the weld strip and blow in a certain direction. Direct current (DC) welding produces severe magnetic blow, while alternating current (AC) welding is much weaker. For wide weld strips, especially those wider than 60mm, the uneven current distribution is more pronounced. Because of the width of the weld strip, the connection between different parts and the welding power source and workpiece varies, leading to inconsistent current magnitude and direction across different parts of the weld strip. This, in turn, results in an uneven magnetic field distribution around the weld strip, triggering magnetic blow. Magnetic blow leads to arc instability and irregular droplet transition, making defects such as undercut (a depression or groove formed along the weld toe in the base metal, reducing the effective load-bearing area of ​​the weld and lowering the strength of the weld joint) and uneven weld bead development more likely.

[0029] Specifically, to ensure that the conveying speed of the first welding strip 210 is less than the conveying speed of the second welding strip 220, the welding head 200 in this embodiment of the invention is provided with a first roller 230 and a second roller 240, such as... Figure 3 and Figure 4As shown, two first supports 203 are fixedly installed at the upper end of the welding head 200. A first roll 230 and a second roll 240 are rotatably mounted on the two first supports 203, respectively. The axes of the first roll 230 and the second roll 240 are parallel to each other. A first welding strip 210 is wound around the first roll 230, and a second welding strip 220 is wound around the second roll 240. The first roll 230 and the second roll 240 are not on the same plane, but their approaching end faces are on the same plane. When the first welding strip 210 and the second welding strip 220 are unwound from the first roll 230 and the second roll 240, respectively, they can be inserted into the welding head 200. Furthermore, the first welding strip 210 and the second welding strip 220... The two welding strips 220 can be arranged side by side and on the same plane. In this embodiment, the welding head 200 is provided with a first drive roller 250 and a second drive roller 260. There are two first drive rollers 250 and they clamp the first welding strip 210. The first drive rollers 250 rotate to transport the first welding strip 210 to the lower end of the welding head 200. There are also two second drive rollers 260. The two second drive rollers 260 clamp the second welding strip 220. The second drive rollers 260 rotate to transport the second welding strip 220 to the lower end of the welding head 200. The rotation speed of the second drive rollers 260 is greater than the rotation speed of the first drive rollers 250, so that the conveying speed of the first welding strip 210 is less than the conveying speed of the second welding strip 220.

[0030] It should be noted that in this embodiment, the first drive roller 250 and the second drive roller 260 are each driven by a drive motor. For ease of description, the drive motor that drives the first drive roller 250 to rotate is named the first drive motor 270, and the drive motor that drives the second drive roller 260 to rotate is named the second drive motor 280. The first drive motor 270 is fixedly disposed on the outside of the welding head 200, and the rotating shaft of the first drive motor 270 is coaxial and fixedly connected to the first drive roller 250. The second drive motor 280 is fixedly disposed on the other side of the outside of the welding head 200, and the rotating shaft of the second drive motor 280 is coaxial and fixedly connected to the second drive roller 260.

[0031] In a further embodiment, since the first welding strip 210 and the second welding strip 220 in this invention are slidably arranged side by side, in order to reduce the gap when the first welding strip 210 and the second welding strip 220 are arranged side by side, this embodiment provides a clamping component on the two sides of the first welding strip 210 and the second welding strip 220 that are far apart from each other. The clamping component can slidably clamp the two sides of the first welding strip 210 and the second welding strip 220 that are far apart from each other, and apply a certain force so that the sides of the first welding strip 210 and the second welding strip 220 that are sliding together can slide and fit together, thereby reducing the gap between the first welding strip 210 and the second welding strip 220, improving the quality of submerged arc welding, and the clamping component does not affect the conveying of the first welding strip 210 and the second welding strip 220 when clamping.

[0032] Specifically, the clamping assembly in this embodiment includes multiple elastic top blocks 310 and two inclined plates 300, such as... Figure 10 and Figure 11 As shown, two inclined plates 300 are vertically slidably connected inside the weld overlay head 200. Each of the two inclined plates 300 has an inclined surface on its side closest to each other, and these inclined surfaces are symmetrical. Multiple elastic top blocks 310 are horizontally slidably disposed on the side of the first weld strip 210 and the second weld strip 220 away from each other. The weld overlay head 200 has multiple horizontally extending through slots inside, and the multiple elastic top blocks 310 are slidably disposed within these slots. One end of each elastic top block 310 rolls in contact with the side of the first weld strip 210 and the second weld strip 220 away from each other, while the other end slides against the inclined surfaces of the two inclined plates 300 that are close to each other. Figure 11 As shown, in this embodiment, a sliding rod 320 is horizontally slidably disposed at one end of a plurality of elastic top blocks 310 near the first welding strip 210 and the second welding strip 220. A roller 330 is rotatably disposed on one end of the sliding rod 320, and the roller 330 rolls in contact with the first welding strip 210 or the second welding strip 220. The other end of the sliding rod 320 is inserted into the elastic top block 310, and a compression spring 340 is sleeved on the outer periphery of the sliding rod 320, providing elasticity. In this embodiment, two inclined plates 300 are configured to move upward as the conveying time of the first welding strip 210 and the second welding strip 220 increases. When the two inclined plates 300 move upward, they can push the plurality of elastic top blocks 310 toward the first welding strip 210 and the second welding strip 220 through the inclined surface, thereby causing the plurality of elastic top blocks 310 to be pushed. The force exerted by the plurality of elastic top blocks 310 on the first welding strip 210 and the second welding strip 220 increases, thereby reducing the gap between the first welding strip 210 and the second welding strip 220.

[0033] It should be noted that since the first welding strip 210 is wound on the first winding roller 230 and the second welding strip 220 is wound on the second winding roller 240, the first welding strip 210 and the second welding strip 220 will still have a tendency to bend when they are stretched and unwound. At this time, the pressure exerted by the multiple elastic top blocks 310 on the first welding strip 210 and the second welding strip 220 can keep the first welding strip 210 and the second welding strip 220 in a straight state when they are conveyed by the welding head 200. As the unwinding time of the first welding strip 210 and the second welding strip 220 increases, the bending tendency of the first welding strip 210 and the second welding strip 220 becomes greater (this is because the diameter of the first welding strip 210 or the second welding strip 220 is smaller when it is closer to the inside of the winding, and the degree of bending of the first welding strip 210 or the second welding strip 220 during winding is greater). Therefore, the pressure exerted by the multiple elastic top blocks 310 on the first welding strip 210 and the second welding strip 220 gradually increases.

[0034] Specifically, to ensure that the two inclined plates 300 move upwards as the unwinding time of the first welding strip 210 and the second welding strip 220 increases, in this embodiment, the upper ends of the two inclined plates 300 are fixedly connected and equipped with vertically extending racks 350, such as... Figure 3 and Figure 12 As shown, a gear 360 is rotatably connected to the upper end of the welding head 200. Specifically, a second bracket 204 is fixedly installed on the upper end of the welding head 200, and the gear 360 is rotatably mounted on the second fixed bracket. The gear 360 meshes with a rack 350, and when the gear 360 rotates, it can drive the rack 350 to move. A detection rod 370 is fixedly installed at the axial position of the gear 360. In this embodiment, there are two racks 350 and two gears 360. A detection rod 370 is fixedly installed at the axial position of both gears 360. The other ends of the two detection rods 370 slide in contact with the upper part of the first roller 230 on which the first welding strip 210 is wound and the upper part of the second roller 240 on which the second welding strip 220 is wound, respectively. A detection rod 370 is provided at the rotatable connection position between the gear 360 and the welding head 200. There is an elastic element 380, which is a torsion spring. The elastic element 380 causes the detection rod 370 to tend to rotate downward around the rotation center. Under the action of the elastic element 380, the detection rod 370 can contact the first welding strip 210 wound on the first roller 230 and the second welding strip 220 wound on the second roller 240. As the first welding strip 210 and the second welding strip 220 are continuously conveyed, the remaining amount of the first welding strip 210 and the second welding strip 220 on the first roller 230 and the second roller 240 becomes less and less. Therefore, under the action of the elastic element 380, the detection rod 370 will rotate downward around the rotation center, thereby driving the two inclined plates 300 to move upward through the gear 360 to increase the force on the first welding strip 210 and the second welding strip 220 that are side by side.

[0035] In a further embodiment, in order to make the gap smaller when the first welding strip 210 and the second welding strip 220 are side by side, a triangular protrusion 211 is provided on the side of the first welding strip 210 near the second welding strip 220, and a triangular groove 221 is provided on the side of the second welding strip 220 near the first welding strip 210, with the triangular protrusion 211 and the triangular groove 221 slidingly engaged.

[0036] It should be noted that, since the first roller 230 and the second roller 240 in this embodiment only have their end faces close to each other on the same plane, and the first welding strip 210 and the second welding strip 220 on the first roller 230 and the second roller 240 are both fed into the welding head 200, the first roller 230 and the second roller 240 rotate in opposite directions, which makes the first welding strip 210 and the second welding strip 220 bend in different directions and in opposite directions. When the triangular protrusion 211 and the triangular groove 221 are provided, the opposite bending directions and forces of the first welding strip 210 and the second welding strip 220 can cancel each other out, so that the first welding strip 210 and the second welding strip 220 can be better aligned side by side.

[0037] It should also be noted that in the existing technology, when using a wider welding strip to start welding a circular workpiece 500, because the welding strip is wider, it is necessary to manually cut the end of the welding strip into a pointed shape first, so that it is easier to start the arc at the beginning. However, the cutting operation is required every time welding begins, which is too cumbersome and complicated.

[0038] Therefore, to overcome the above problems, the welding head 200 in this embodiment needs to adjust the positions of the first welding strip 210 and the second welding strip 220 when welding begins. At the start of welding, the initial length of the first welding strip 210 is longer than the initial length of the second welding strip 220, or the initial length of the second welding strip 220 is longer than the initial length of the first welding strip 210. That is, the first welding strip 210 or the second welding strip 220 is closer to the surface of the circular workpiece 500, so that the overall width of the portion of the first welding strip 210 and the second welding strip 220 close to the circular workpiece 500 before welding begins is narrower. A narrower width makes it easier to ignite an arc. The sum of the widths of the first welding strip 210 and the second welding strip 220 in this invention is the same as that of the wider welding strips in the prior art. However, it is not necessary to trim the first welding strip 210 or the second welding strip 220 during welding to easily ignite an arc, simplifying the process.

[0039] Specifically, when one round of welding on the surface of the circular workpiece 500 is almost finished, the first welding strip 210 or the second welding strip 220 will stop feeding prematurely, allowing the second welding strip 220 or the first welding strip 210 to continue feeding and thus coincide with the position at the beginning of the welding process, ensuring the connection quality of the start and end of each round of welding. For example, if the first welding strip 210 is closer to the surface of the circular workpiece 500 at the start of welding, the first welding strip 210 will form a molten pool on the inner side first, and the second welding strip 220 will subsequently form a molten pool on the outer side, resulting in a gap between the start ends of the first welding strip 210 and the second welding strip 220. Their start ends are not flush. When one round of welding is almost finished, the first welding strip 210 will stop feeding prematurely (the advance time is calculated based on the radius of the circular workpiece 500 to ensure a seamless connection between the end and the start end), and the end of the first welding strip 210 will seamlessly connect with the start end before the second welding strip 220 stops feeding, ensuring the connection quality of the start and end of each round of welding. The end of the welding strip 220 is seamlessly connected to the beginning end. If the second welding strip 220 is closer to the surface of the circular workpiece 500 when the welding begins, the second welding strip 220 will form a molten pool on the outer side first, and the first welding strip 210 will then form a molten pool on the inner side, so that there is a gap between the beginning end of the first welding strip 210 and the beginning end of the second welding strip 220. The beginning ends of the two are not flush. When the welding is about to end, the second welding strip 220 will stop feeding in advance, and the end of the second welding strip 220 will be seamlessly connected to the beginning end in advance. Then the feeding of the first welding strip 210 will stop, so that the end of the first welding strip 210 is seamlessly connected to the beginning end.

[0040] In a further embodiment, the weld overlay head 200 of the present invention has an inner layer 201 and an outer layer 202, such as Figure 6 As shown, the inner layer 201 of the welding head 200 is used to convey the first welding strip 210 and the second welding strip 220. There is a cavity between the inner layer 201 and the outer layer 202 of the welding head 200. This cavity is connected to the material conveying bin 290. The material conveying bin 290 is filled with flux, and the flux in the material conveying bin 290 will be output from the outer periphery of the first welding strip 210 and the second welding strip 220 through the cavity between the inner layer 201 and the outer layer 202 of the welding head 200, thereby covering the electric arc generated by the first welding strip 210 and the second welding strip 220 and realizing the submerged arc function.

[0041] In a further embodiment, a collection pipe 400 is also provided on one side of the welding head 200 of the present invention. The opening of the collection pipe 400 is on the rear side of the welding head 200 relative to the circular workpiece 500 in the direction of movement. A vacuum pump 410 is connected to the collection pipe 400. The vacuum pump 410 makes the collection pipe 400 negative pressure, and the collection pipe 400 can collect the excess flux after the welding is completed.

[0042] The specific working process of the continuous welding device for a petrochemical hydrogenation reactor provided by the present invention will be described in conjunction with the above embodiments: After adjusting the position of the welding head 200, the operator drives the rotating disk 120 to rotate. The rotating disk 120 drives the circular workpiece 500 to rotate around its own axis. The rotation parameters of the first drive motor 270 and the second drive motor 280 on the welding head 200 are adjusted so that the conveying speed of the first welding strip 210 is less than the conveying speed of the second welding strip 220, and the first welding strip 210 is brought closer to the surface of the circular workpiece 500. The welding power is then turned on, so that the first welding strip 210, the second welding strip 220 and the circular workpiece 500 form an electrical circuit. The inner layer 201 of the welding head 200 is then opened. The cavity between the outer layers 202 allows flux to fall. The electric arc generated between the first welding strip 210 and the second welding strip 220 and the surface of the circular workpiece 500 gradually melts the first welding strip 210 and the second welding strip 220 to form a molten pool. The flux falling into the cavity covers the electric arc. The rotating disk 120 slowly rotates to gradually build up a circle of welding on the surface of the circular workpiece 500. During the welding process, the vacuum pump 410 is started. The vacuum pump 410 makes the collection pipe 400 negative pressure. The opening of the collection pipe 400 is located on one side of the welding head 200 to collect the residual flux after the welding is completed.

[0043] When one round of welding is about to be completed, the first welding strip 210 will stop feeding first, and the end of the first welding strip 210 will approach the beginning of the first welding strip 210. Then the second welding strip 220 will stop feeding, and the end of the second welding strip 220 will approach the beginning of the second welding strip 220 before stopping. Then the welding head 200 will be driven to move radially inward along the circular workpiece 500 to start welding the second round. When starting welding the second round, the first welding strip 210 or the second welding strip 220 will be adjusted to be closer to the surface of the circular workpiece 500. Then the welding of the second round will begin, and so on, until the surface of the circular workpiece 500 is welded round by round, and the welding process of the circular workpiece 500 is completed.

[0044] This invention also provides a continuous welding process for a petrochemical hydrogenation reactor, comprising the following steps: Step S100: Adjust the conveying speed of the first welding strip 210 and the second welding strip 220 according to the processing parameters of the circular workpiece 500, so that the conveying speed of the first welding strip 210 is less than the conveying speed of the second welding strip 220.

[0045] Step S200: Adjust the first welding strip 210 or the second welding strip 220 to be close to the surface of the circular workpiece 500.

[0046] Specifically, adjusting the first welding strip 210 or the second welding strip 220 to be closer to the surface of the circular workpiece 500 makes the first welding strip 210 and the second welding strip 220 easier to ignite an arc.

[0047] Step S300: After each weld is completed, adjust the weld head 200 to move radially inward along the circular workpiece 500 by a preset distance.

[0048] The preset distance refers to the sum of the widths of the first welding strip 210 and the second welding strip 220. After each round of welding is completed, the workpiece moves radially inward by the preset distance to start the second round of welding, and so on, until the entire surface of the circular workpiece 500 is welded.

[0049] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0050] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. A continuous welding device for a petrochemical hydrogenation reactor, characterized in that, include: A frame, on which a worktable is provided, and a circular workpiece is rotatably connected to the worktable; A mobile platform is located close to the frame. A support arm is vertically fixed on the mobile platform, and a cantilever extending laterally is vertically slidably mounted on the support arm. The welding body is laterally slidably mounted on the cantilever. The welding body includes a welding head and a material conveying bin. The welding head conveys two parallel and relatively sliding first and second welding strips. The first welding strip is located inside the second welding strip and the conveying speed of the first welding strip is less than that of the second welding strip. The material conveying bin is filled with flux. The flux is discharged from the outer periphery of the welding head and falls onto a circular workpiece to cover the electric arc.

2. The continuous welding apparatus for a petrochemical hydrogenation reactor according to claim 1, characterized in that, The welding head is provided with a first roll and a second roll, the axes of the first roll and the second roll are parallel to each other, and the end faces of the first roll and the second roll that are close to each other are on the same plane. The first welding strip is wound on the first roll and the second welding strip is wound on the second roll. The welding head is provided with a first drive roller and a second drive roller. There are two first drive rollers that hold the first welding strip and two second drive rollers that hold the second welding strip. The rotation speed of the first drive roller is less than the rotation speed of the second drive roller.

3. The continuous welding apparatus for a petrochemical hydrogenation reactor according to claim 2, characterized in that, Clamping components are provided on both sides of the first and second welding strips. The clamping components are used to slide and clamp the first and second welding strips so that they are placed side by side. The clamping force of the clamping components on the first and second welding strips is positively correlated with the conveying time of the first and second welding strips.

4. The continuous welding apparatus for a petrochemical hydrogenation reactor according to claim 3, characterized in that, The clamping assembly includes multiple elastic top blocks and two inclined plates. The two inclined plates are vertically slidably connected inside the weld head. The sides of the two inclined plates that are close to each other are inclined surfaces. The multiple elastic top blocks are horizontally slidably disposed on the side where the first weld strip and the second weld strip are far apart. One end of the multiple elastic top blocks makes rolling contact with the side where the first weld strip and the second weld strip are far apart, and the other end of the multiple elastic top blocks slides against the inclined surfaces of the two inclined plates. The two inclined plates are configured to move upward as the first weld strip and the second weld strip are conveyed for longer periods. The two inclined plates push the multiple elastic top blocks toward the first weld strip and the second weld strip.

5. The continuous welding apparatus for a petrochemical hydrogenation reactor according to claim 4, characterized in that, Two inclined plates are fixedly connected at their upper ends and are provided with vertically extending racks. A gear is rotatably provided at the upper end of the welding head. The gear meshes with the rack. A detection rod extending radially along the gear is fixedly provided at the center of the gear shaft. One end of the detection rod is fixed to the gear, and the other end of the detection rod slides in contact with the top of the first roller on which the first welding strip is wound or the second roller on which the second welding strip is wound. An elastic element is provided at the rotatable connection position between the gear and the welding head. The elastic element causes the detection rod to have a tendency to rotate downward around the rotation center.

6. The continuous welding apparatus for a petrochemical hydrogenation reactor according to claim 1, characterized in that, The first welding strip has a triangular protrusion on the side near the second welding strip, and the second welding strip has a triangular groove on the side near the first welding strip. The triangular protrusion and the triangular groove are slidably engaged.

7. The continuous welding apparatus for a petrochemical hydrogenation reactor according to claim 1, characterized in that, The welding head has an inner layer and an outer layer, with a cavity between the inner and outer layers. The cavity is connected to the material conveying bin, and the inner layer of the welding head is used to convey the first welding strip and the second welding strip.

8. The continuous welding apparatus for a petrochemical hydrogenation reactor according to claim 1, characterized in that, A collection pipe is also provided on one side of the welding head, and the opening of the collection pipe is located on the rear side of the welding head relative to the direction of movement of the circular workpiece.

9. The continuous welding apparatus for a petrochemical hydrogenation reactor according to claim 8, characterized in that, A vacuum pump is connected to the collection pipe.

10. A continuous welding process for a petrochemical hydrogenation reactor, applicable to the continuous welding apparatus for the petrochemical hydrogenation reactor described in any one of claims 1-9, characterized in that, Includes the following steps: Step S100: Adjust the conveying speed of the first and second welding strips according to the processing parameters of the circular workpiece, so that the conveying speed of the first welding strip is less than the conveying speed of the second welding strip. Step S200: Adjust the first or second welding strip to be close to the surface of the circular workpiece; Step S300: After each round of welding is completed, adjust the welding head to move inward a preset distance along the radial direction of the circular workpiece.

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