An automatic submerged arc welding machine for the inner circumferential seam of a boiler

Abstract

The present invention discloses an automatic submerged arc welding machine for inner circumferential seams of boilers, which relates to the technical field of welding. It includes a wire feeding assembly, inside which there is a welding wire. At the lower end of the wire feeding assembly, there is a support frame. On both sides of the support frame, there are respectively a hopper and an air suction pipe. At the lower end of the hopper, there is a flux feeding mechanism for piling up the flux and changing the gap between flux particles. The vibration ring and vibration piece provided in the present invention adjust the gap between flux particles. The vibration piece that transmits small-amplitude vibration to the inside of the flux can adjust the gap between flux particles, forming a moderate porosity. The appropriate gap allows the gas generated during the welding process (such as moisture decomposition gas) to be discharged smoothly, reducing porosity defects. The optimized particle gap helps the heat to be evenly transferred to the flux and the workpiece surface. The vibration prevents the flux particles from adhering to each other due to static electricity or humidity, ensuring their loose state, which is convenient for subsequent recycling and reuse.

Description

Technical Field

[0001] The present invention relates to the field of welding technology, and particularly relates to an automatic submerged arc welding machine for the inner circumferential seam of a boiler. Background Art

[0002] For example, the publication number is CN110773849B, and the patent name is a gantry type tower pipe seam welding machine. Among them, the solution provided by the invention has a compact structure, can adjust the position of the seam pressure application point and the direction of the acting force on both sides of the tower pipe according to the change of the cross-sectional shape of the tower pipe, and can coarsely adjust and finely adjust the mechanism position in a timely manner according to the change of the straightness of the seam gap, so as to realize the automatic correction of the position of the submerged arc welding head.

[0003] In the submerged arc welding of the inner circumferential seam of a boiler, when the flux is unevenly distributed, it is easy to cause defects in the molten pool flow such as slag inclusion, lack of fusion and impurity mixing, which will exacerbate the risk of porosity. When the flux accumulates, the poor shape of the flux accumulation will cause problems such as oxidation, nitridation pollution and inconsistent forming of the weld edge. And when there is moisture and oxide layer on the surface of the welding wire, it is easy to produce hydrogen-induced cracks and unstable arcs. Therefore, the present application provides an automatic submerged arc welding machine for the inner circumferential seam of a boiler to meet the requirements. Summary of the Invention

[0004] The purpose of the present application is to provide an automatic submerged arc welding machine for the inner circumferential seam of a boiler, which can effectively solve the problems proposed in the above background art.

[0005] To achieve the above purpose, the present application provides the following technical solution: An automatic submerged arc welding machine for the inner circumferential seam of a boiler, including a wire feeding assembly. A welding wire is arranged inside the wire feeding assembly. A support frame is arranged at the lower end of the wire feeding assembly. A hopper and an air suction pipe are respectively arranged on both sides of the support frame. A flux feeding mechanism for accumulating flux and changing the gap between flux particles is arranged at the lower end of the hopper. A wire treatment mechanism for improving the arc starting performance of the welding wire is arranged in the middle of the support frame. A molten pool control mechanism for improving the arc stability is arranged on one side of the wire treatment mechanism. The molten pool control mechanism is located between the flux feeding mechanism and the wire treatment mechanism. A flux collecting mechanism for cleaning the flux and cooling the weld seam is arranged at the lower end of the air suction pipe.

[0006] Among them, the wire treatment mechanism includes a heating shell, which is installed in the middle of the lower end of the support frame. A heating coil is arranged inside the heating shell. An air hood is arranged at the lower end of the heating shell. A wire barrel is arranged in the middle of the air hood. A welding gun head is arranged inside the wire barrel. The welding wire passes through the heating coil and the wire barrel and extends into the inside of the welding gun head.

[0007] Among them, an air supply pipe is connected to the outer surface of the air hood, and a ring hood is arranged on the outer surface of the air hood and is communicated with the inside of the air hood.

[0008] Among them, the molten pool control mechanism includes a gas guide shell, which is installed on the outer surface of the ring cover and communicates with the inside of the ring cover. A conduit is provided at the bottom of the gas guide shell, and a material shell is installed at the bottom of the conduit. A push rib is provided on one side of the material shell.

[0009] Among them, the inner wall of the material shell is connected with a material stacking and shaping shell through a partition block. A baffle is installed on the inner wall of the push rib. A number of strip holes are formed in the inner wall of the material stacking and shaping shell. A guiding piece is installed between the material stacking and shaping shell and the material shell through the partition block.

[0010] Among them, both the material stacking and shaping shell and the material shell are in a shape conforming to "Ω".

[0011] Among them, the flux feeding mechanism includes a discharge pipe, which is installed at the lower end of the hopper. A vibration ring is provided on the outer surface of the discharge pipe. A vibration piece that penetrates into the flux is provided inside the vibration ring. A discharge nozzle is provided at the lower end of the discharge pipe, and the cross section of the discharge nozzle is in a streamlined water droplet shape.

[0012] Among them, the flux feeding mechanism further includes two guiding pieces. Mounting blocks are provided on the opposite surfaces of the two guiding pieces, and the two guiding pieces are respectively installed on both sides of the discharge nozzle through the mounting blocks for shaping the flux.

[0013] Among them, the flux collection mechanism includes a suction pipe, which is installed at the lower end of the suction air pipe. A suction nozzle is provided at the lower end of the suction pipe. A bronchus is communicated with the outer surface of the suction pipe. An elastic bracket for supporting the bronchus is provided between the suction pipe and the bronchus;

[0014] A cover shell is provided at the lower end of the bronchus. Mounting strips are provided on both sides of the cover shell, and skirt edges are sleeved on the outer surfaces of the two mounting strips.

[0015] Among them, a boiler frame is provided inside the wire feeding assembly, and a wire reel for winding the welding wire is provided on one side of the wire feeding assembly.

[0016] In summary, the technical effects and advantages of the present invention:

[0017] 1. In the present invention, the streamlined water-drop-shaped discharging nozzle can guide the flux to flow out at a stable flow rate, avoiding excessive or insufficient accumulation of the flux caused by uneven discharging. The special design of the front section of the discharging nozzle (such as a sharp or beveled structure) can scrape off the oxide scale, dust or other impurities on the weld surface, reducing inclusion defects (such as slag inclusions or lack of fusion) in the weld. Moreover, the vibration ring and vibration plate are provided to adjust the gaps between the flux particles. By transmitting small-amplitude vibrations to the vibration plate inside the flux, the gaps between the flux particles can be adjusted to form a moderate porosity. Appropriate gaps allow the gases generated during the welding process (such as moisture decomposition gases) to be discharged smoothly, reducing porosity defects. The optimized particle gaps contribute to uniform heat transfer to the flux and the workpiece surface. Vibration prevents the flux particles from adhering to each other due to static electricity or humidity, ensuring their loose state and facilitating subsequent recycling and reuse.

[0018] 2. In the present invention, the Ω-shaped design of the stockpiling shaping shell and the material shell guides the flux to accumulate into a trapezoidal cross-section, ensuring that a thicker protective layer is formed on both sides of the weld, reducing the risk of the edge area being exposed to air, and decreasing the probability of oxidation and nitridation defects. The inclined structure of the trapezoidal cross-section can guide the molten pool metal to flow along a predetermined path, avoiding overflow or uneven accumulation of the molten metal, and improving the consistency of the weld formation. The flux enters the shaping shell as the boiler welding part rotates, ensuring that the flux is always in the optimal accumulation form during the dynamic welding process. The baffle guides the gas to blow onto the surface of the flux, forming a continuous inert gas layer to isolate oxygen and nitrogen in the air. Moreover, the strip-shaped holes on the surface of the stockpiling shaping shell accelerate the entry of the gas into the gaps between the flux particles, ensuring that the internal pores of the flux are also filled with the inert gas to further isolate the air. Additionally, the gas introduced through the wire handling mechanism has a preheating temperature (from the wire cooling process), preheating the flux particles and reducing the moisture content on their surfaces. Preheating reduces the adsorption of hydrogen in the flux, avoiding porosity or cracks caused by hydrogen generated from the decomposition of moisture at high temperatures.

[0019] 3. In the present invention, the heating coil heats the wire, evaporating the moisture adsorbed on its surface, avoiding the decomposition of moisture to generate hydrogen at high temperatures, thereby reducing the formation of porosity and hydrogen-induced cracks and cleaning the surface. The heating process can remove the oil stain, oxide layer or other impurities on the wire surface, ensuring a pure contact between the wire and the molten pool, reducing slag inclusion or lack of fusion defects. After preheating, the surface temperature of the wire increases, reducing the difficulty of arc ignition and the risk of arc drift or extinction during starting, ensuring the continuity and stability of the welding process. Moreover, the preheated wire penetrates into the flux processed by the molten pool control mechanism, ensuring that the arc burns under a stable protective layer, reducing oxidation and nitridation caused by the intrusion of external air. The temperature matching between the wire and the flux can optimize the heat input distribution in the molten pool, reducing local overheating or uneven cooling and improving the consistency of the weld formation. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those skilled in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0021] Figure 1 It is a first perspective three-dimensional structural schematic diagram of an automatic submerged arc welding machine for the inner circumferential seam of a boiler;

[0022] Figure 2 It is a second perspective three-dimensional structural schematic diagram of an automatic submerged arc welding machine for the inner circumferential seam of a boiler;

[0023] Figure 3 It is a third perspective three-dimensional structural schematic diagram of an automatic submerged arc welding machine for the inner circumferential seam of a boiler;

[0024] Figure 4 It is a partial first perspective three-dimensional connection structural schematic diagram of an automatic submerged arc welding machine for the inner circumferential seam of a boiler;

[0025] Figure 5 It is a partial second perspective three-dimensional connection structural schematic diagram of an automatic submerged arc welding machine for the inner circumferential seam of a boiler;

[0026] Figure 6 It is a three-dimensional connection structural schematic diagram of a wire handling mechanism and a molten pool control mechanism;

[0027] Figure 7 It is a sectional view of the three-dimensional connection structure of the wire handling mechanism;

[0028] Figure 8 It is a three-dimensional connection structural schematic diagram of the molten pool control mechanism;

[0029] Figure 9 It is a partial three-dimensional connection structural schematic diagram of the molten pool control mechanism;

[0030] Figure 10 It is a three-dimensional connection structural schematic diagram of a stacking and shaping shell and a material shell;

[0031] Figure 11 It is a three-dimensional connection structural schematic diagram of the stacking and shaping shell;

[0032] Figure 12 It is a three-dimensional connection structural schematic diagram of a flux feeding mechanism;

[0033] Figure 13 It is a three-dimensional connection structural schematic diagram of a discharge nozzle and a discharge pipe;

[0034] Figure 14 It is a three-dimensional connection structural schematic diagram of a guide plate and a discharge pipe;

[0035] Figure 15 Schematic diagram of the first - perspective three - dimensional connection structure of the flux collection mechanism;

[0036] Figure 16 Schematic diagram of the second - perspective three - dimensional connection structure of the flux collection mechanism.

[0037] In the figure: 1. Boiler frame; 2. Wire spool; 3. Wire feeding assembly; 5. Flux feeding mechanism; 51. Discharge pipe; 52. Vibration ring; 53. Vibration piece; 54. Guide piece; 55. Discharge nozzle; 56. Installation block; 6. Molten pool control mechanism; 61. Air guide shell; 62. Conduit; 63. Material shell; 64. Push rib; 65. Baffle; 66. Stockpiling and shaping shell; 67. Strip - shaped hole; 68. Guide piece; 7. Wire processing mechanism; 71. Air hood; 72. Welding gun head; 73. Gas supply pipe; 74. Heating shell; 75. Bobbin; 76. Heating coil; 77. Ring hood; 8. Flux collection mechanism; 81. Suction pipe; 82. Suction nozzle; 83. Branch pipe; 84. Elastic bracket; 85. Cover shell; 86. Skirt; 87. Installation strip; 9. Suction air pipe; 10. Hopper; 11. Support frame; 12. Welding wire. Specific implementation mode

[0038] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0039] Embodiment 1. Refer to Figures 1 to 16 A kind of automatic submerged - arc welding machine for the inner - ring seam of a boiler shown in the figure, which includes a wire feeding assembly 3. Inside the wire feeding assembly 3, there is a welding wire 12. At the lower end of the wire feeding assembly 3, there is a support frame 11. On both sides of the support frame 11, there are respectively a hopper 10 and a suction air pipe 9. At the lower end of the hopper 10, there is a flux feeding mechanism 5 for piling up flux and changing the gap between flux particles. In the middle of the support frame 11, there is a wire processing mechanism 7 for improving the arc - starting performance of the welding wire 12. On one side of the wire processing mechanism 7, there is a molten pool control mechanism 6 for improving the arc stability. The molten pool control mechanism 6 is located between the flux feeding mechanism 5 and the wire processing mechanism 7. At the lower end of the suction air pipe 9, there is a flux collection mechanism 8 for cleaning the flux and cooling the weld seam.

[0040] Inside the wire feeding assembly 3, there is a boiler frame 1. On one side of the wire feeding assembly 3, there is a wire spool 2 for winding the welding wire 12.

[0041] It is worth noting that when the boiler welding part is used, the boiler welding part is placed under the boiler frame 1. When the boiler is welded, the flux feeding mechanism 5 deposits the flux inside the hopper 10 on the boiler welding part, and the transmission device arranged at the bottom of the boiler welding part drives the boiler welding part to rotate, and the flux feeding mechanism 5 leaks the material inside the hopper 10 and deposits it on the weld. When depositing the flux, the flux feeding mechanism 5 also performs preliminary shaping on the deposited flux, and changes the gap between the flux particles by vibrating with a small amplitude.

[0042] Among them, the flux feeding mechanism 5 controls the release amount and distribution of the flux to ensure that the flux evenly covers the welding area, avoids local excessive thickness or thinness, can form a stable arc environment, and reduce the uneven melting depth or arc drift caused by uneven flux.

[0043] Moreover, the initial shaping of the flux feeding mechanism 5 ensures that the flux accumulation shape meets the welding requirements, provides a stable combustion space for the arc, and reduces the risk of arc drift or extinction. Among them, the gap between the flux particles is adjusted by small vibrations to form an appropriate porosity, which helps the gas generated during the welding process (such as hydrogen and water decomposition gas) to be discharged smoothly and reduce the generation of pore defects. The flux accumulation shape after shaping can cover the molten pool area more tightly, reduce air intrusion, reduce the risk of oxidation and nitride contamination, and improve the purity of the weld.

[0044] In addition, the gap between flux particles is adjusted so that heat is evenly transferred to the flux and the workpiece surface, promoting the metallurgical reaction between the flux and the molten metal (such as deoxidation and desulfurization), thereby improving the chemical composition and mechanical properties of the weld. Vibration can prevent flux particles from sticking to each other due to static electricity or humidity, ensuring their loose state for subsequent recycling and reuse. By controlling the flux accumulation shape, optimizing the particle gap and uniform coverage, welding defects such as porosity, slag inclusions and incomplete fusion can be significantly reduced, thereby improving the mechanical properties and corrosion resistance of the weld.

[0045] When the flux feeding mechanism 5 has completed stacking the flux, the molten pool control mechanism 6 gathers the flux so that the cross-section of the flux is stacked in a trapezoidal shape, and the molten pool control mechanism 6 fills the interior of the flux with inert gas while gathering the welding, and the filled gas passes through the welding wire processing mechanism 7 and cools the welding wire processing mechanism 7 so that the gas filled in the gaps between the flux particles has a temperature, thereby being able to preheat the flux.

[0046] Among them, shaping the flux cross section into a trapezoidal shape can guide the molten pool metal to flow along a predetermined path during welding, avoiding overflow or uneven accumulation of molten metal. The inclined structure of the trapezoid helps to evenly distribute the molten pool, especially in circumferential welding, which can form a more stable penetration and weld formation. The trapezoidal cross section ensures that the flux forms a thicker protective layer on both sides of the weld, reducing the risk of the edge area being exposed to the air, thereby reducing the probability of oxidation and nitridation defects.

[0047] Inert gas is filled into the flux (such as argon or helium), further isolating air, preventing the molten metal from reacting with oxygen and nitrogen, reducing the formation of oxides and nitrides, and improving the purity and mechanical properties of the weld. Moreover, the heat carried by the inert gas preheats the flux, reducing the moisture content in the flux (especially in a humid environment), reducing the risk of hydrogen-induced cracks. At the same time, the combination of the preheated flux and the high-temperature arc can accelerate metallurgical reactions (such as deoxidation and desulfurization), optimizing the chemical composition of the weld metal.

[0048] Moreover, when the welding wire 12 passes through the wire processing mechanism 7, the moisture adsorbed on its surface is evaporated by the wire processing mechanism 7, avoiding the decomposition of moisture at high temperature to generate hydrogen, thereby reducing the formation of pores and hydrogen-induced cracks. The preheated flux combines with the surface-treated welding wire, making it easier to ignite and stably burn the arc. The drying treatment of the welding wire surface reduces the risk of drift or extinction during arc ignition.

[0049] The heat carried by the inert gas not only preheats the flux but also optimizes the heat input distribution in the molten pool, making the heat transfer to the workpiece and the flux more uniform, reducing defects caused by local overheating or uneven cooling. The filling and preheating of the inert gas work together to promote the rapid discharge of gases (such as moisture decomposition gases) generated during the welding process, reducing the formation of pores.

[0050] When the molten pool control mechanism 6 plastically processes the flux again, the wire processing mechanism 7 drives the welding wire 12 to penetrate into the flux and contact the boiler welding part. The set wire feeding assembly 3 continuously pushes the welding wire 12 into the wire processing mechanism 7. The welding wire 12 pushed by the wire feeding assembly 3 runs synchronously with the conveying device at the bottom of the boiler welding part. When the welding wire 12 passes through the wire processing mechanism 7, the wire processing mechanism 7 conducts preliminary heat treatment on the welding wire 12, raising the temperature of the welding wire 12 to evaporate the moisture on its surface, making the arc ignition of the welding wire 12 more stable in the flux, and combining with the flux processed by the molten pool control mechanism 6 to form a more stable molten pool.

[0051] Among them, the wire processing mechanism 7 conducts preliminary heat treatment on the welding wire 12, evaporating the moisture (such as hydrogen) adsorbed on its surface, avoiding the decomposition of moisture at high temperature to generate pores or trigger hydrogen-induced cracks. The surface temperature of the preheated welding wire 12 rises, reducing the difficulty of arc ignition and reducing problems such as arc drift or extinction caused by humidity or low temperature, ensuring the continuity and stability of the welding process. The preheated welding wire 12 combines with the pretreated flux, accelerating the metallurgical reactions (such as deoxidation and alloying) between the two, and improving the purity and mechanical properties of the weld metal.

[0052] The molten pool control mechanism 6 reshapes the flux again (such as a trapezoidal cross-section), guides the uniform distribution of the molten pool metal, avoids the overflow or uneven accumulation of the molten metal, and can form a more stable penetration depth and weld formation. It is especially suitable for welding complex structures (such as boiler circumferential seams). The reshaped flux accumulation form ensures the uniform coverage of the protective layer around the molten pool, reduces oxidation and nitridation caused by air intrusion, and improves the purity of the weld.

[0053] After the welding of the boiler weldment is completed using the flux, the flux collection mechanism 8 collects the flux that has passed through the wire processing mechanism 7 by suction, and the flux collection mechanism 8 also cools the weld during the collection of the flux.

[0054] Among them, the flux collection mechanism 8 can evenly take away the heat of the weld, avoid the concentration of thermal stress caused by local overheating or different cooling rates, reduce the risk of welding deformation and cracks. The slow and uniform cooling process helps to release the residual stress accumulated during the welding process. During the cooling process, the airflow can remove the oxide layer or residual flux on the weld surface, and the airflow during the cooling process can assist in discharging the oxides on the weld surface, reducing inclusion defects caused by oxidation.

[0055] Embodiment 2: Based on the flux feeding mechanism 5 proposed in Embodiment 1, this embodiment provides a further technical solution for the flux feeding mechanism 5.

[0056] The flux feeding mechanism 5 includes a discharge pipe 51, the discharge pipe 51 is installed at the lower end of the hopper 10, a vibration ring 52 is arranged on the outer surface of the discharge pipe 51, a vibration piece 53 extending into the flux is arranged inside the vibration ring 52, a discharge nozzle 55 is arranged at the lower end of the discharge pipe 51, and the cross-section of the discharge nozzle 55 is in a streamlined water droplet shape.

[0057] The flux feeding mechanism 5 further includes two guiding pieces 54, mounting blocks 56 are arranged on the opposite surfaces of the two guiding pieces 54, and the two guiding pieces 54 are respectively installed on both sides of the discharge nozzle 55 through the mounting blocks 56 for shaping the flux.

[0058] It should be noted that when the flux is accumulated, the flux falls into the inside of the discharge pipe 51 through the hopper 10, and the flux falls into the inside of the discharge nozzle 55 through the discharge pipe 51. The discharge nozzle 55 is in a streamlined water droplet shape, so that the front section of the discharge nozzle 55 can clean the sundries in the weld, and then the flux leaks through the discharge nozzle 55 and accumulates at the weld of the boiler part. The set discharge nozzle 55 is in Figure 12 and Figure 13In the shown shape, after the flux flows out from the discharge nozzle 55, the provided guide piece 54 preliminarily plastifies the flux, making the shape of the accumulated flux line consistent. The vibration ring 52 transmits force to the vibration piece 53 through the internal vibration motor, and the vibration piece 53 penetrates into the flux. By slightly vibrating the vibration piece 53, the gap between the particles in the flux is changed.

[0059] Among them, the streamlined water-drop-shaped discharge nozzle 55 can guide the flux to flow out at a stable flow rate, avoiding too thick or too thin accumulation of the flux caused by uneven discharging. The special design (such as a sharp or beveled structure) at the front section of the discharge nozzle 55 can scrape off the oxide scale, dust or other impurities on the weld surface, reducing inclusion defects (such as slag inclusion or lack of fusion) in the weld. And the provided vibration ring 52 and vibration piece 53 adjust the gap between the flux particles. The vibration piece 53 that transmits to the inside of the flux through slight vibration can adjust the gap between the flux particles, forming a moderate porosity. The appropriate gap allows the gas (such as moisture decomposition gas) generated during the welding process to be discharged smoothly, reducing porosity defects. The optimized particle gap helps the heat to be evenly transmitted to the flux and the workpiece surface. Vibration prevents the flux particles from adhering to each other due to static electricity or humidity, ensuring its loose state and facilitating subsequent recycling and reuse.

[0060] Embodiment 3: For the molten pool control mechanism 6 proposed in Embodiment 1, this embodiment provides a further technical solution for the molten pool control mechanism 6.

[0061] The molten pool control mechanism 6 includes a gas guide shell 61. The gas guide shell 61 is installed on the outer surface of the ring cover 77 and is communicated with the inside of the ring cover 77. A conduit 62 is provided at the bottom of the gas guide shell 61, and a material shell 63 is installed at the bottom of the conduit 62. A push rib 64 is provided on one side of the material shell 63.

[0062] The inner wall of the material shell 63 is connected with a material stacking and shaping shell 66 through a partition block. A stop piece 65 is installed on the inner wall of the push rib 64. A number of strip-shaped holes 67 are opened on the inner wall of the material stacking and shaping shell 66. A guide piece 68 is installed between the material stacking and shaping shell 66 and the material shell 63 through a partition block.

[0063] It should be noted that after the preliminary plastic treatment by the flux feeding mechanism 5, the flux will be fed into the interior of the stockpiling and shaping shell 66 as the boiler part rotates. The welding machine enters the interior of the stockpiling and shaping shell 66 through the baffle 65. The set stockpiling and shaping shell 66 and the material shell 63 are both in the shape of "Ω", so that the interface of the flux plasticized by the stockpiling and shaping shell 66 is trapezoidal. The inert gas fed into the interior of the gas guide shell 61 through the wire treatment mechanism 7 will be fed into the gap between the material shell 63 and the stockpiling and shaping shell 66 through the conduit 62. The baffle 65 first shapes the flux, and the baffle 65 will guide the gas between the stockpiling and shaping shell 66 and the material shell 63 to blow on the surface of the flux. Moreover, the strip-shaped holes 67 opened on the surface of the stockpiling and shaping shell 66 will also accelerate the gas to blow into the particle gaps between the fluxes;

[0064] Since the temperature for cooling the wire treatment mechanism 7 is attached to the gas blown into the gas guide shell 61 through the wire treatment mechanism 7, the gas blown into the flux gap will also carry a temperature to preheat the flux particles. The set guide piece 68 guides the gas to perform a secondary gas filling treatment on the flux particles plasticized by the stockpiling and shaping shell 66.

[0065] Among them, the Ω-shaped design of the stockpiling and shaping shell 66 and the material shell 63 guides the flux to accumulate into a trapezoidal cross-section, ensuring that a thicker protective layer is formed on both sides of the weld, reducing the risk of the edge area being exposed to the air, and reducing the probability of oxidation and nitridation defects. The inclined structure of the trapezoidal cross-section can guide the molten pool metal to flow along a predetermined path, avoiding the overflow or uneven accumulation of the molten metal, and improving the consistency of the weld formation. The flux enters the shaping shell as the boiler welding part rotates, ensuring that the flux is always in the best stockpiling form during the dynamic welding process. The baffle 65 guides the gas to blow on the surface of the flux, forming a continuous inert gas layer to isolate oxygen and nitrogen in the air. Moreover, the strip-shaped holes 67 on the surface of the stockpiling and shaping shell 66 accelerate the gas to enter the flux particle gaps, ensuring that the internal pores of the flux are also filled with inert gas to further isolate the air.

[0066] The gas introduced through the wire treatment mechanism 7 has a preheating temperature (from the wire cooling process), preheating the flux particles and reducing the moisture content on their surfaces. The preheating reduces the adsorption of hydrogen in the flux, avoiding the hydrogen generated by the decomposition of moisture at high temperatures from causing pores or cracks.

[0067] Example 4. According to the wire treatment mechanism 7 proposed in Example 1, this example provides a further technical solution for the wire treatment mechanism 7.

[0068] The wire electrode treatment mechanism 7 includes a heating shell 74, which is installed in the middle of the lower end of the support frame 11. A heating coil 76 is arranged inside the heating shell 74. A gas hood 71 is arranged at the lower end of the heating shell 74. A wire reel 75 is arranged in the middle of the gas hood 71. A welding torch head 72 is arranged inside the wire reel 75. The wire electrode 12 passes through the heating coil 76 and the wire reel 75 and extends into the inside of the welding torch head 72.

[0069] An air supply pipe 73 is connected to the outer surface of the gas hood 71. A ring hood 77 is arranged on the outer surface of the gas hood 71, and the ring hood 77 communicates with the inside of the gas hood 71.

[0070] It should be noted that when the wire electrode 12 is pushed by the wire feeding assembly 3, it will be sent into the inside of the wire reel 75. Before the wire electrode 12 passes through the wire reel 75, it will pass through the heating coil 76, and the heating coil 76 heats the passing wire electrode 12 to clean the moisture or debris on the surface of the wire electrode 12 and perform a temperature rise treatment on the wire electrode 12. The wire electrode 12 after the heating treatment will enter the inside of the welding torch head 72 through the wire reel 75. The wire electrode 12 after the temperature rise treatment penetrates into the welding flux processed by the molten pool control mechanism 6, making the wire electrode 12 strike an arc more stably. And after the gap of the welding machine is processed and combined with the inert gas at the gap of the welding flux, the control of the molten pool generated by the welding of the welding torch head 72 is optimized;

[0071] And the inert gas entering the inside of the gas hood 71 through the air supply pipe 73 will take away the temperature on the surface of the wire reel 75, thereby controlling the temperature transmitted from the welding torch head 72 to the wire reel 75. The gas that absorbs heat will be sent into the inside of the molten pool control mechanism 6 through the ring hood 77. And the gas flow rate inside the air supply pipe 73 is relatively low to ensure that the molten pool control mechanism 6 will not blow away the welding machine when filling the gas into the gaps between the welding flux particles.

[0072] Among them, the heating coil 76 heats the wire electrode 12 to evaporate the moisture adsorbed on its surface, avoiding the decomposition of moisture at high temperature to generate hydrogen, thereby reducing the formation of pores and hydrogen-induced cracks and cleaning the surface. The heating process can remove the oil stains, oxide layers or other impurities on the surface of the wire electrode 12, ensure the pure contact between the wire electrode 12 and the molten pool, reduce the defects of slag inclusion or lack of fusion. The surface temperature of the preheated wire electrode rises, reducing the difficulty of arc ignition and the risk of drift or extinction during arc striking, ensuring the continuity and stability of the welding process.

[0073] And the preheated wire electrode 12 penetrates into the welding flux processed by the molten pool control mechanism 6 to ensure that the arc burns under a stable protective layer, reducing oxidation and nitridation caused by the intrusion of external air. The temperature matching between the wire electrode 12 and the welding flux can optimize the distribution of the heat input to the molten pool, reduce local overheating or uneven cooling, and improve the consistency of the weld formation.

[0074] Example 5. The flux collection mechanism 8 proposed according to Example 1. This example provides a further technical solution for the flux collection mechanism 8.

[0075] The flux collection mechanism 8 includes a suction pipe 81, which is installed at the lower end of the suction air pipe 9. A suction nozzle 82 is provided at the lower end of the suction pipe 81. A bronchial tube 83 is communicated with the outer surface of the suction pipe 81. An elastic bracket 84 for supporting the bronchial tube 83 is provided between the suction pipe 81 and the bronchial tube 83.

[0076] The lower end of the bronchial tube 83 is provided with a cover shell 85. Installation strips 87 are provided on both sides of the cover shell 85. Skirts 86 are sleeved on the outer surfaces of the two installation strips 87.

[0077] It should be noted that when the flux passes through the flux treatment mechanism 7 for flux treatment, a small amount of flux particles do not participate in the welding process. At this time, the air extraction device at one end of the suction air pipe 9 extracts the air inside the suction pipe 81, and the suction pipe 81 extracts a small amount of flux particles at the weld through the suction nozzle 82. When the suction air pipe 9 extracts the air inside the suction pipe 81, part of the suction force will be dispersed in the bronchial tube 83, and the air at the bottom of the cover shell 85 is extracted through the bronchial tube 83. The provided cover shell 85 is attached to the weld on the surface of the boiler through the skirt 86, and the cover shell 85 can cool the weld during welding.

[0078] Among them, the small amount of flux particles that did not participate in the welding at the weld are accurately extracted through the suction nozzle 82, avoiding waste caused by scattering or residue. The recycled flux can be reused after screening and drying. And the cover shell 85 is closely attached to the weld surface through the skirt 86 to form a sealed space, cooperating with the bronchial tube 83 to extract the air at the bottom, accelerating the heat transfer from the weld to the outside, controlling the cooling rate, and forming a convection of air flow inside the cover shell 85, reducing local overheating or uneven cooling of the weld, and reducing welding deformation and residual stress.

[0079] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An automatic submerged arc welding machine for the inner circumferential seam of a boiler, comprising a wire feeding assembly (3), wherein a welding wire (12) is arranged inside the wire feeding assembly (3), and a support frame (11) is arranged at the lower end of the wire feeding assembly (3), and is characterized in that: On both sides of the support frame (11), a hopper (10) and an air suction pipe (9) are respectively arranged. At the lower end of the hopper (10), a flux feeding mechanism (5) is provided for accumulating the flux and changing the gaps between the flux particles. In the middle of the support frame (11), a wire processing mechanism (7) is provided for improving the starting arc performance of the welding wire (12). On one side of the wire processing mechanism (7), a molten pool control mechanism (6) is provided for improving the arc stability. The molten pool control mechanism (6) is located between the flux feeding mechanism (5) and the wire processing mechanism (7). At the lower end of the air suction pipe (9), a flux collecting mechanism (8) is provided for cleaning the flux and cooling the weld seam. The flux feeding mechanism (5) includes a discharge pipe (51). The discharge pipe (51) is installed at the lower end of the hopper (10). A vibration ring (52) is arranged on the outer surface of the discharge pipe (51). Inside the vibration ring (52), a vibration piece (53) extending into the flux is provided. At the lower end of the discharge pipe (51), a discharge nozzle (55) is provided. The cross-section of the discharge nozzle (55) is in the shape of a streamlined water droplet. The flux feeding mechanism (5) further includes two guiding pieces (54). On the opposite surfaces of the two guiding pieces (54), mounting blocks (56) are arranged. And the two guiding pieces (54) are respectively installed on both sides of the discharge nozzle (55) through the mounting blocks (56) for shaping the flux.

2. The automatic submerged arc welding machine for the inner circumferential seam of the boiler according to claim 1, characterized in that: The wire processing mechanism (7) includes a heating shell (74). The heating shell (74) is installed in the middle of the lower end of the support frame (11). Inside the heating shell (74), a heating coil (76) is provided. At the lower end of the heating shell (74), an air hood (71) is provided. In the middle of the air hood (71), a wire cylinder (75) is provided. Inside the wire cylinder (75), a welding gun head (72) is provided. The welding wire (12) passes through the heating coil (76) and the wire cylinder (75) and extends into the inside of the welding gun head (72).

3. The automatic submerged arc welding machine for the inner circumferential seam of the boiler according to claim 2, characterized in that: An air supply pipe (73) is connected to the outer surface of the air hood (71). A ring hood (77) is arranged on the outer surface of the air hood (71), and the ring hood (77) communicates with the inside of the air hood (71).

4. The automatic submerged arc welding machine for inner circumferential seams of a boiler according to claim 1, characterized in that: The molten pool control mechanism (6) includes a gas guiding shell (61). The gas guiding shell (61) is installed on the outer surface of the ring hood (77) and communicates with the inside of the ring hood (77). At the bottom of the gas guiding shell (61), a conduit (62) is provided. At the bottom of the conduit (62), a material shell (63) is installed. On one side of the material shell (63), a pushing rib (64) is provided.

5. The automatic submerged arc welding machine for the inner circumferential seam of a boiler according to claim 4, characterized in that: The inner wall of the material shell (63) is connected to a material stacking and shaping shell (66) through a partition block. A blocking piece (65) is installed on the inner wall of the pushing rib (64). A plurality of strip-shaped holes (67) are formed in the inner wall of the material stacking and shaping shell (66). A guiding piece (68) is installed between the material stacking and shaping shell (66) and the material shell (63) through a partition block.

6. The automatic submerged arc welding machine for the inner circumferential seam of a boiler according to claim 5, characterized in that: Both the material stacking and shaping shell (66) and the material shell (63) are in the shape of "Ω".

7. The automatic submerged arc welding machine for the inner circumferential seam of a boiler according to claim 1, wherein: The flux collecting mechanism (8) includes a suction pipe (81), the suction pipe (81) is installed at the lower end of the suction air pipe (9), a suction nozzle (82) is arranged at the lower end of the suction pipe (81), a bronchus (83) is communicated with the outer surface of the suction pipe (81), and an elastic bracket (84) for supporting the bronchus (83) is arranged between the suction pipe (81) and the bronchus (83); A cover shell (85) is arranged at the lower end of the bronchus (83), mounting strips (87) are arranged on both sides of the cover shell (85), and skirt edges (86) are sleeved on the outer surfaces of the two mounting strips (87).

8. The automatic submerged arc welding machine for the inner circumferential seam of a boiler according to claim 1, wherein: A boiler frame (1) is arranged inside the wire feeding assembly (3), and a wire reel (2) for winding a welding wire (12) is arranged on one side of the wire feeding assembly (3).

Images