Gas shielded laser welding device for niobium alloy in atmospheric environment

Abstract

The utility model relates to a gas-shielded laser welding device for niobium alloy in an atmospheric environment. The gas-shielded laser welding device comprises a shielding gas supporting cover, an adjusting mechanism and a gas spraying assembly, a to-be-welded workpiece is placed below the protective gas supporting cover, and a welding seam of the workpiece corresponds to the protective gas supporting cover; one end of the adjusting mechanism is installed on the shielding gas supporting cover, a laser welding gun of the laser welding device is installed at the other end of the adjusting mechanism, and a light emitting point of the laser welding gun corresponds to a welding seam of a workpiece. The air injection assembly is installed in the protective gas supporting cover, corresponds to a welding seam of the workpiece and is used for protecting molten metal in the welding process of the workpiece and welding seam metal in the high-temperature state in the welding process. According to the utility model, the niobium alloy can be welded at a smaller oxidation degree in an atmospheric environment, the cost of adopting a vacuum chamber is reduced, and the welding efficiency is improved.

Description

Technical Field

[0001] This utility model relates to the field of nozzle welding technology, and in particular to a gas-shielded laser welding device for niobium alloys in an atmospheric environment. Background Technology

[0002] The nozzle, a crucial component of a rocket engine, is a device that accelerates airflow by altering the geometry of its inner wall. In a rocket engine, the nozzle throat area controls the gas flow rate, maintaining a predetermined pressure within the combustion chamber. This allows the propellant combustion products to expand and accelerate through the nozzle, converting their thermal energy into kinetic energy, thus providing propulsion. Currently, most liquid rocket engine main unit nozzles in China employ a jacketed structure, which offers the advantage of mature manufacturing processes, typically using vacuum brazing, argon arc welding, and laser welding.

[0003] However, the manufacturing of jacketed nozzles has the following problems: 1. The structure itself is relatively heavy, which is not conducive to improving the thrust-to-weight ratio of the engine; 2. Vacuum brazing and laser welding have relatively strict requirements on the fitting gap between the inner and outer walls of the jacketed nozzle. The larger the nozzle size, the more difficult it is to control the fitting gap between the inner and outer walls in the pre-machining process, so it is difficult to manufacture large-diameter jacketed nozzles.

[0004] Therefore, single-wall nozzles have irreplaceable advantages, namely: 1. The overall weight of the single-layer structure is more advantageous, which is conducive to improving the thrust-to-weight ratio of the engine; 2. By using welding, a large-size nozzle can be obtained in the single-layer structure, thereby enabling the rocket to obtain a greater specific impulse.

[0005] Niobium alloys are the preferred material for single-wall nozzles due to their high melting point and good high-temperature performance. However, tests have shown that niobium alloys have poor oxidation resistance; once oxidized, the material's performance deteriorates sharply. When welded in an atmospheric environment, the weld area and heat-affected zone are very prone to oxidation, resulting in unsatisfactory welding results.

[0006] Currently, the optimal choice is to use vacuum electron beam welding of niobium alloys in a large-sized vacuum chamber, which can produce welds with excellent weld performance and superior mechanical properties. However, in practical engineering applications, large-sized vacuum chambers are very expensive, resulting in high costs and low vacuuming efficiency, leading to low welding efficiency, making them unsuitable for mass production.

[0007] Therefore, how to weld niobium alloys with a lower degree of oxidation in a non-vacuum (atmospheric environment) environment, thereby reducing the cost of using large-size vacuum chambers and improving welding efficiency, has become an urgent problem to be solved. Utility Model Content

[0008] The purpose of this invention is to provide a gas-shielded laser welding device for niobium alloys in an atmospheric environment, so as to solve the problems existing in the prior art.

[0009] To achieve the above objectives, this utility model provides the following solution:

[0010] This utility model provides a gas-shielded laser welding device for niobium alloys in an atmospheric environment, including a protective gas shield, an adjustment mechanism, and a jet assembly, wherein:

[0011] The workpiece to be welded is placed below the protective gas support, and the weld seam of the workpiece is set corresponding to the protective gas support.

[0012] One end of the adjustment mechanism is mounted on the protective gas support cover, and the other end of the adjustment mechanism is mounted on the laser welding gun of the laser welding device. The light emission point of the laser welding gun is set to correspond to the weld seam of the workpiece.

[0013] The jet assembly is installed inside the protective gas support cover. The jet assembly is configured to correspond to the weld seam of the workpiece. The jet assembly is used to protect the molten metal and the weld metal at high temperature during the welding process.

[0014] According to one embodiment of the present invention, the adjustment mechanism includes a height adjustment rod, which is vertically arranged. The bottom end of the height adjustment rod is installed on the top end of the protective gas support cover. A second adjustment block is bolted and slidably mounted on the top of the height adjustment rod. The relative sliding direction between the second adjustment block and the height adjustment rod is arranged along the length direction of the height adjustment rod. A first adjustment block is bolted and slidably mounted on the second adjustment block. The relative sliding direction between the first adjustment block and the second adjustment block is horizontal and arranged along the direction of the jet assembly towards or away from the light emission point of the laser welding gun. A second connecting block is bolted and slidably mounted on the first adjustment block. The relative sliding direction between the second connecting block and the first adjustment block is horizontal and perpendicular to the relative sliding direction of the first and second adjustment blocks. The laser welding gun of the laser welding device is detachably mounted on the end of the second connecting block.

[0015] According to one embodiment of the present invention, a first connecting block is rotatably mounted on the top of the protective air support cover, and the end of the first connecting block is rotatably connected to the bottom end of the height adjustment rod. The height adjustment rod is mounted on the top of the protective air support cover through the first connecting block.

[0016] According to one embodiment of the present invention, the height adjustment rod is a polygonal prism structure.

[0017] According to one embodiment of the present invention, the jet assembly includes a first jet mechanism and a second jet mechanism. The first jet mechanism is located between the light emission point of the laser welding gun and the second jet mechanism, and both the first jet mechanism and the second jet mechanism are correspondingly arranged to the weld seam of the workpiece. The first jet mechanism is used to protect the molten metal during the welding process of the workpiece, and the second jet mechanism is used to protect the weld metal at a high temperature during the welding process of the workpiece.

[0018] According to one embodiment of the present invention, the first jetting mechanism includes an oblique air outlet duct formed at the bottom end of the protective gas support cover, the oblique air outlet duct being located between the laser welding gun's emission point and the second jetting mechanism; the bottom end of the oblique air outlet duct is correspondingly arranged to the weld seam of the workpiece, a first ventilation component is installed on the protective gas support cover, the top end of the oblique air outlet duct is connected to one end of the first ventilation component, and the other end of the first ventilation component is connected to an external blower.

[0019] According to one embodiment of the present invention, the angle between the bottom end of the inclined air outlet and the bottom end of the protective air cover is or is substantially 45°.

[0020] According to one embodiment of the present invention, the second jet mechanism includes a third air pipe installed inside the protective air support cover. A second vent is installed on the protective air support cover. One end of the second vent is connected to one end of the third air pipe, and the other end of the second vent is connected to an external blower. A venting groove is provided at the bottom end of the protective air support cover. The inclined air outlet is located between the venting groove and the light emission point of the laser welding gun. The top end of the venting groove is connected to the third air pipe. A first perforated plate is fixedly installed on the inner wall of the bottom end of the venting groove. The first perforated plate is correspondingly arranged with the weld seam of the workpiece. The venting groove and the third air pipe are both independently arranged from the inclined air outlet.

[0021] According to one embodiment of the present invention, the third air pipe is located at the top of the ventilation groove, and a second perforated plate is provided between the third air pipe and the first perforated plate, and the inner wall of the ventilation groove is fixedly connected to the side wall of the second perforated plate.

[0022] According to one embodiment of the present invention, the third air pipe is connected to several branch air pipes at one end near the inclined air outlet, and the branch air pipes are independently set up with respect to the inclined air outlet; the third air pipe and the branch air pipes are each provided with several ventilation holes that correspond one-to-one with the holes on the second perforated plate, and a small tube is provided between each hole on the second perforated plate and its corresponding ventilation hole, and both ends of each small tube are fixedly connected to the second perforated plate and its corresponding ventilation hole, respectively; the third air pipe and the branch air pipes are all connected to the ventilation groove through the ventilation holes and the small tubes.

[0023] This utility model has at least the following technical effects:

[0024] This invention provides a gas-shielded laser welding device for niobium alloys in an atmospheric environment. By setting up an air jet assembly, this invention can spray air onto the molten metal and the weld metal at high temperature during the welding process of niobium alloys. This allows for welding of niobium alloys with a lower degree of oxidation in a non-vacuum (atmospheric environment) environment, so that the weld performance coefficient reaches more than 90% of the base material. This reduces the cost of using a large-size vacuum chamber and improves welding efficiency. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0027] Figure 2 for Figure 1 The front view;

[0028] Figure 3 for Figure 2 A cross-sectional view along the AA direction;

[0029] Figure 4 for Figure 3 A magnified view of a section at point B in the middle;

[0030] Figure 5 This is a schematic diagram of the overall structure of the protective air support cover from the top side in this utility model;

[0031] Figure 6 This is a schematic diagram of the overall structure of the protective air support cover from the lower side in this utility model;

[0032] Figure 7 for Figure 6 The front view;

[0033] Figure 8 for Figure 6 A cross-sectional view along the TT direction;

[0034] Figure 9 for Figure 7 Side view;

[0035] Figure 10 for Figure 9 A cross-sectional view along the FF direction;

[0036] Figure 11 for Figure 9 A cross-sectional view along the GG direction;

[0037] Figure 12 This is a schematic diagram of the overall structure of the first adjusting block and the second connecting block in this utility model;

[0038] Among them, 1. Protective air support cover; 2. First connecting block; 3. Height adjustment rod; 4. First adjustment block; 5. Second adjustment block; 6. Second connecting block; 7. First air pipe; 8. Second air pipe; 9. Workpiece; 10. First perforated plate; 11. Third air pipe; 12. Branch air pipe; 13. Second perforated plate; 14. Angled air outlet. Detailed Implementation

[0039] The features and exemplary embodiments of various aspects of this utility model will be described in detail below. To make the objectives, technical solutions, and advantages of this utility model clearer, the following detailed description is provided in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only configured to explain this utility model and to exemplarily illustrate the principles of this utility model, and are not configured to limit this utility model. In addition, the structural components in the drawings are not necessarily drawn to scale. For example, the dimensions of some structural components or regions in the drawings may be enlarged for other structural components or regions to aid in the understanding of the embodiments of this utility model.

[0040] The directional terms used in the following description refer to the directions shown in the figures and are not intended to limit the specific structure of the embodiments of this utility model. In the description of this utility model, it should be noted that, unless otherwise stated, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0041] Furthermore, the terms "comprising," "including," "having," or any other variations thereof are intended to cover non-exclusive inclusion, such that a structure or component that includes a list of elements includes not only those elements but also other structural elements that are not expressly listed or inherent to the structure or component. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the article or apparatus that includes the element.

[0042] Spatial relation terms such as "below," "under," "under," "low," "above," "on," and "high" are used for descriptive convenience to explain the positioning of one element relative to a second element, indicating that these terms are intended to cover different orientations of the device, in addition to those different from those shown in the figure. Furthermore, phrases such as "one element on / below another element" can indicate that two elements are in direct contact, or that there are other elements between the two elements. In addition, terms such as "first" and "second" are also used to describe individual elements, areas, parts, etc., without specifically indicating order or sequence, and should not be considered restrictive. Similar terms are used throughout the description to represent similar elements.

[0043] For those skilled in the art, this invention can be implemented without some of these specific details. The following description of the embodiments is merely intended to provide a better understanding of the invention by illustrating examples.

[0044] This utility model provides a gas-shielded laser welding device for niobium alloys in an atmospheric environment, including a protective gas shield 1, an adjustment mechanism, and a jet assembly, wherein:

[0045] The workpiece 9 to be welded is placed below the protective gas support 1. The weld seam of the workpiece 9 is set in correspondence with the protective gas support 1. Preferably, the weld seam of the workpiece 9 is set at the center position directly below the protective gas support 1.

[0046] In this embodiment, refer to Figure 1 The workpiece 9 is divided into two parts, left and right, and preferably, niobium alloy plates are used as the two workpieces 9 to be welded, with a thickness of 1mm-2mm. The shape of the weld can be a straight line. However, those skilled in the art can also use the laser welding device of this invention to weld niobium alloy plates of other shapes, such as curved welds, depending on the actual situation, and this is not particularly limited here.

[0047] In this embodiment, refer to Figure 9 The protective air shield 1 can be roughly shaped as a polygonal prism with a trapezoidal cross section, and its length is set along the weld of the workpiece 9.

[0048] One end of the adjustment mechanism is mounted on the protective gas support 1, preferably rotatably mounted on the top of the protective gas support 1. The adjustment mechanism can be used to precisely and quantitatively adjust the position of the protective gas support 1. The other end of the adjustment mechanism is equipped with a laser welding gun (not shown in the figure) of the laser welding device. The laser welding gun's light emission point (i.e., the laser welding gun head) is set to correspond to the weld seam of the workpiece 9. Preferably, the laser welding gun's light emission point is set directly above the weld seam of the workpiece 9, so that subsequent welding work can be carried out better.

[0049] Laser welding guns are existing technologies known to those skilled in the art, such as fiber laser welding guns and solid-state laser welding guns. Those skilled in the art can also select different types of laser welding guns according to the actual welding situation, and disassemble and install them on the adjustment mechanism; no particular limitations are made here.

[0050] The laser welding device disclosed in this utility model can be installed on a robot and welded to the workpiece 9 through the robot's automatic control. The use of robot automatic control for welding is a prior art known in the art. During welding, the robot can control the laser welding gun on this device to move along the weld of the workpiece 9, thereby achieving the welding of the workpiece 9 weld.

[0051] The jet assembly is installed inside the protective air support shroud 1, and the jet assembly is positioned corresponding to the weld of the workpiece 9. Preferably, the jet assembly is positioned directly above the weld of the workpiece 9.

[0052] In one embodiment of the present invention, the jet assembly includes a first jet mechanism and a second jet mechanism. The first jet mechanism is located between the light emission point of the laser welding gun and the second jet mechanism. Both the first jet mechanism and the second jet mechanism are arranged corresponding to the weld seam of the workpiece 9, and preferably both are arranged directly above the weld seam of the workpiece 9.

[0053] When the laser welding torch welds the weld seam of workpiece 9, the laser emitted by the laser welding torch melts the metal on both sides of the weld seam of workpiece 9 into a molten state, thereby achieving the welding of the weld seam of workpiece 9. In this process, since the first jet mechanism is located between the laser emission point of the laser welding torch and the second jet mechanism, after the weld seam of workpiece 9 becomes molten, it will first be below the first jet mechanism as the device moves. At this time, the metal near the weld seam of workpiece 9 has not yet cooled down and is still in a molten state (i.e., a molten pool). The first jet mechanism can spray air onto the weld seam of workpiece 9 to prevent the molten metal at the weld seam of workpiece 9 from oxidizing, thus achieving a protective effect. At the same time, the airflow can also be used to quickly cool down the molten metal at the weld seam of workpiece 9, accelerating the cooling rate of the molten metal.

[0054] Next, the second jetting mechanism moves to a position above the weld seam of workpiece 9 as the device moves. At this point, the metal at the weld seam of workpiece 9 is not in a molten state but in a solidified state, although the temperature is still high. The second jetting mechanism can then spray air onto the weld seam of workpiece 9 again, thus providing secondary protection for the high-temperature metal at the weld seam and preventing oxidation. This further accelerates the cooling rate of the metal at the weld seam of workpiece 9.

[0055] Furthermore, due to deviations in the preceding sheet metal and machining processes, gaps of 0.1mm-0.3mm or misalignments of 0.1mm-0.4mm may occur locally during the welding of the two niobium alloy workpieces 9. Therefore, a clamping method can be used during the welding process, i.e., simultaneously clamping the two niobium alloy workpieces 9 to reduce the misalignment to within 0.2mm, allowing the welding work to proceed more smoothly.

[0056] In this embodiment, when clamping the two niobium alloy workpieces 9 on the left and right sides to reduce misalignment, clamping components known to those skilled in the art can be used, such as C-clamps or F-clamps, etc., and are not particularly limited here.

[0057] According to one embodiment of the present invention, the adjusting mechanism includes a height adjusting rod 3. In this embodiment, referring to... Figure 1 Preferably, there is one height adjustment rod 3. The height adjustment rod 3 is vertically arranged, and its bottom end is installed on the top of the protective air support 1. Preferably, it is bolted and rotatably installed on the top of the protective air support 1. The operator can loosen the bolt connecting the height adjustment rod 3 and the protective air support 1 and adjust the tilt angle of the protective air support 1 according to the actual situation. After adjustment, tighten the bolt connecting the height adjustment rod 3 and the protective air support 1 to complete the adjustment of the tilt angle of the protective air support 1.

[0058] The top of the height adjustment rod 3 is bolted and slidably fitted with a second adjustment block 5; in this embodiment, refer to... Figure 1 The second adjusting block 5 is preferably of an I-shape. The relative sliding direction between the second adjusting block 5 and the height adjusting rod 3 is set along the length direction of the height adjusting rod 3. When it is necessary to adjust the height of the protective air support 1, loosen the bolts at the connection between the second adjusting block 5 and the height adjusting rod 3, and then let the height adjusting rod 3 slide up or down in the second adjusting block 5, thereby adjusting the height of the protective air support 1. After adjustment, tighten the bolts on the second adjusting block 5 to re-fix the second adjusting block 5 and the height adjusting rod 3.

[0059] The first adjusting block 4 is bolt-fixed and slidably mounted on the second adjusting block 5. In this embodiment, refer to... Figure 1or Figure 12 The first adjusting block 4 is preferably a U-shaped structure, and the second adjusting block 5, which is I-shaped, is placed vertically. The recessed parts on both sides of the second adjusting block 5 are respectively engaged with the outer wall inside the opening of the first adjusting block 4, thereby realizing the limiting sliding connection between the second adjusting block 5 and the first adjusting block 4. The relative sliding direction of the first adjusting block 4 and the second adjusting block 5 is set horizontally and along the direction of the first jet mechanism toward or away from the light emission point of the laser welding gun. That is, the opening of the U-shaped first adjusting block 4 is set parallel to the length direction of the protective gas support 1, so as to ensure that the second adjusting block 5 can slide on the first adjusting block 4 along the length direction of the protective gas support 1, thereby adjusting the distance between the first jet mechanism and the light emission point of the laser welding gun along the length direction of the protective gas support 1.

[0060] When it is necessary to adjust the distance between the first jet mechanism and the laser welding gun's emission point, loosen the bolt connecting the second adjusting block 5 and the first adjusting block 4, and the second adjusting block 5 can slide relative to the first adjusting block 4; after adjustment, tighten the bolt connecting the second adjusting block 5 and the first adjusting block 4 to re-fix them, thereby completing the adjustment of the distance between the first jet mechanism and the laser welding gun's emission point.

[0061] The first adjusting block 4 is bolted and slidably mounted with a second connecting block 6. In this embodiment, refer to... Figure 1 The second connecting block 6 is a bent L-shaped structure. One end of it is slidably connected to the first adjusting block 4, and the other end is detachably connected to the laser welding gun via two bolts. The relative sliding direction of the second connecting block 6 and the first adjusting block 4 is horizontal, and the relative sliding direction of the first adjusting block 4 and the second adjusting block 5 is perpendicular. That is, the relative sliding directions of the height adjusting rod 3, the first adjusting block 4, and the second adjusting block 5 are all perpendicular to each other, forming relative sliding directions in the XYZ axes. A sliding groove is provided on the second connecting block 6, and the end of the first adjusting block 4 near the second connecting block 6 extends into the sliding groove, thereby slidingly engaging with the second connecting block 6.

[0062] When it is necessary to adjust the left and right positions of the protective air support 1, refer to... Figure 12 Loosen the bolts (preferably two) at the bottom of the second connecting block 6 that connect to the first adjusting block 4, and then slide the first adjusting block 4 left and right in the sliding groove to adjust the left and right position of the protective air support 1. After adjustment, tighten the bolts at the bottom of the second connecting block 6 that connect to the first adjusting block 4 to complete the re-fixation of the two and the adjustment of the left and right position of the protective air support 1.

[0063] According to one embodiment of the present invention, a first connecting block 2 is rotatably mounted on the top of the protective air support 1 by bolts. In this embodiment, refer to... Figure 1The length direction of the first connecting block 2 is the same as the length direction of the protective air support 1 and is collinear with the center line of the protective air support 1. The end of the first connecting block 2 is fixedly and rotatably connected to the bottom end of the height adjustment rod 3 by bolts. Preferably, the end of the first connecting block 2 away from the first jet mechanism is fixedly and rotatably connected to the bottom end of the height adjustment rod 3 by bolts. The height adjustment rod 3 is installed on the top of the protective air support 1 through the first connecting block 2.

[0064] By setting the first connecting block 2, the degree of freedom between the height adjustment rod 3 and the protective air cover 1 can be increased, making their adjustment more flexible.

[0065] According to one embodiment of the present invention, the height adjustment rod 3 is a multi-faceted prism structure, preferably a quadrangular prism structure with adjacent sides perpendicular to each other. In this embodiment, referring to... Figure 1 The height adjustment rod 3 can be a cuboid structure, which allows it to act as a limit within the second adjustment block 5, preventing rotation. When adjusting the height of the protective gas support 1, the cuboid structure of the height adjustment rod 3 prevents rotation, ensuring that the weld between the protective gas support 1 and the workpiece 9 remains parallel, thus guaranteeing smooth welding operations.

[0066] According to one embodiment of the present invention, the first jetting mechanism includes an oblique air outlet 14 formed at the bottom end of the protective gas support 1. The oblique air outlet 14 is located between the laser welding gun's emission point and the second jetting mechanism. Preferably, the angle between the bottom end of the oblique air outlet 14 and the bottom end of the protective gas support 1 is 45° or substantially 45°, more preferably 45°. The bottom end of the oblique air outlet 14 corresponds to the weld seam of the workpiece 9. A first vent is installed on the protective gas support 1. The top end of the oblique air outlet 14 is connected to one end of the first vent, and the other end of the first vent is connected to an external blower. Preferably, see reference... Figure 4 The first ventilation component can be a first air tube 7 for ventilation.

[0067] In this embodiment, refer to Figure 4 and Figure 8An oblique air outlet 14 is formed on the centerline of the protective air support 1 along its length, with its bottom end located at the angle between the bottom and side ends of the protective air support 1. The inclination angle of the oblique air outlet 14 is also set along the centerline of the protective air support 1 along its length. The diameter of the opening at the bottom of the oblique air outlet 14 is preferably 4 mm. The first air pipe 7 can be vertically inserted into the top of the protective air support 1 and coaxially arranged with the top end of the oblique air outlet 14, with the bottom end of the first air pipe 7 connected to the top end of the oblique air outlet 14. The connection between the first air pipe 7 and the protective air support 1 can be a fixed connection or a detachable connection known in the art, such as connecting the first air pipe 7 and the protective air support 1 with an adhesive material, which is not particularly limited here.

[0068] When it is necessary to use the first jetting mechanism to spray air onto the molten metal at the weld of workpiece 9 to prevent oxidation, the top end of the first air pipe 7 is connected to an external blower. This allows air to be blown at a 45° angle through the oblique air outlet 14 onto the molten metal at the weld of workpiece 9, thus completing the anti-oxidation work on the molten metal. The blower is a prior art known in the art and will not be described in detail here.

[0069] According to one embodiment of the present invention, the second jet mechanism includes a third air pipe 11 installed inside a protective air support 1. A second vent is installed on the protective air support 1, one end of the second vent is connected to one end of the third air pipe 11, and the other end of the second vent is connected to an external blower. Preferably, see... Figure 4 The second ventilation component can be a second air pipe 8 for ventilation. A ventilation groove is provided at the bottom of the protective gas support shroud 1, and an oblique air outlet 14 is located between the ventilation groove and the laser welding gun's emission point. The top of the ventilation groove is connected to the third air pipe 11, and a first perforated plate 10 is fixedly installed on the inner wall of the bottom of the ventilation groove, corresponding to the weld seam of the workpiece 9. The ventilation groove and the third air pipe 11 are both independently configured from the oblique air outlet 14; that is, neither the ventilation groove nor the third air pipe 11 is connected to the oblique air outlet 14.

[0070] In this embodiment, refer to Figure 4 , Figure 6 and Figure 8 The third air pipe 11 is located on the center line of the protective air support 1 along its length and is arranged horizontally. The second air pipe 8 is inserted into the end of the protective air support 1 away from the oblique air outlet 14 and is coaxially arranged with the third air pipe 11. Its end inside the protective air support 1 is connected to the third air pipe 11. The first perforated plate 10 is fixedly installed horizontally on the inner wall of the bottom end of the ventilation groove. The fixing connection can be any method known in the art, such as fixing by welding. The diameter of the holes on the first perforated plate 10 can preferably be 1 mm.

[0071] When it is necessary to use the second jetting mechanism to spray air onto the high-temperature metal at the weld of workpiece 9 to prevent its oxidation, the end of the second air pipe 8 located outside the protective air support shroud 1 is connected to an external blower known in the art. This allows air to be blown onto the high-temperature metal at the weld of workpiece 9 through the ventilation groove and the first perforated plate 10, thereby completing the anti-oxidation work on the high-temperature metal. The holes on the first perforated plate 10 can evenly distribute the air blown from the ventilation groove to the outside of the protective air support shroud 1, thus improving the anti-oxidation effect on the high-temperature metal.

[0072] According to one embodiment of the present invention, a third air pipe 11 is located at the top of the ventilation groove, and a second perforated plate 13 is disposed between the third air pipe 11 and the first perforated plate 10. The inner wall of the ventilation groove is fixedly connected to the side wall of the second perforated plate 13. Preferably, see... Figure 4 The second perforated plate 13 is also disposed at the top of the venting groove and located below the third air pipe 11. The fixing connection can be made using methods known in the art, such as welding, and is not particularly limited here.

[0073] In this embodiment, refer to Figure 4 The diameter of the holes on the second perforated plate 13 is also preferably 1 mm. (Referring to...) Figure 10 The second perforated plate 13 directly below the third air pipe 11 can be bent upwards at both ends, thereby wrapping around the lower part of the third air pipe 11. By setting the first perforated plate 10 and the second perforated plate 13, the air blown out to the protective air support shroud 1 can be evenly distributed twice, making the even distribution effect better, and thus further improving the anti-oxidation effect on high-temperature metals.

[0074] According to one embodiment of the present invention, the end of the third air pipe 11 near the oblique air outlet 14 is connected to several branch air pipes 12. In this embodiment, refer to... Figure 8 There are two branch air pipes 12, symmetrically arranged on both sides of the inclined air outlet 14. The two branch air pipes 12 and the third air pipe 11 form a Y-shaped structure. The branch air pipes 12 and the inclined air outlet 14 are independently set, that is, the branch air pipes 12 are not connected to the inclined air outlet 14. The third air pipe 11 and the branch air pipes 12 are each provided with several ventilation holes that correspond one-to-one with the holes on the second orifice plate 13. The diameter of the ventilation holes is preferably 1 mm. A small tube (not shown in the figure) is provided between each hole on the second orifice plate 13 and its corresponding ventilation hole, and both ends of each small tube are fixedly connected to the second orifice plate 13 and its corresponding ventilation hole, respectively. The fixed connection can be made by welding or other methods known in the art. The third air pipe 11 and the branch air pipes 12 are connected to the ventilation groove through ventilation holes and small tubes.

[0075] In this embodiment, refer to Figure 10Only the portion of the second perforated plate 13 directly below the third trachea 11 will be bent, while the portion of the second perforated plate 13 directly below the branch trachea 12 will not be bent.

[0076] Since the third air pipe 11 is horizontal and collinear with the oblique air outlet 14, and the third air pipe 11 cannot be connected to the oblique air outlet 14, the end of the third air pipe 11 away from the second air pipe 8 can only be located on one side of the oblique air outlet 14, thus limiting the length of the third air pipe 11 within the protective air support 1. However, by setting the branch air pipe 12, the length of the third air pipe 11 within the protective air support 1 can be indirectly extended without being connected to the oblique air outlet 14 (i.e., the branch air pipe 12 compensates for the length of the third air pipe 11 within the protective air support 1), thereby increasing the air output of the third air pipe 11 within the protective air support 1.

[0077] Furthermore, the vent design allows for one initial airflow equalization of the air exiting the third air pipe 11, plus two additional equalizations from the first orifice plate 10 and the second orifice plate 13, resulting in a total of three airflow equalizations. This further enhances the airflow equalization effect and consequently improves the oxidation resistance of high-temperature metals. The small tubes also guide the air exiting the third air pipe 11 and the second orifice plate 13, increasing the airflow efficiency.

[0078] The welding process of this utility model can be roughly divided into the following steps:

[0079] First, install the laser welding gun on the second connecting block 6 of this device, and set the laser welding gun's output point directly downwards; then, combine the two workpieces 9 to be welded to form the weld seam, and place the weld seam of the two workpieces 9 directly below the laser welding gun's output point; after placement, install this device on the robot.

[0080] Next, the position of the protective air shield 1 needs to be adjusted, which preferably involves the following four steps:

[0081] First, loosen the bolts connecting the protective air support 1 to the first connecting block 2 and the first connecting block 2 to the height adjustment rod 3 in sequence to adjust the angle of the protective air support 1. After adjusting it to be level with the workpiece 9, tighten the bolts connecting the protective air support 1 to the first connecting block 2 and the first connecting block 2 to the height adjustment rod 3 in sequence to complete the adjustment of the level of the protective air support 1.

[0082] The second step involves using a robot to adjust the distance and position between the bottom of the laser welding gun's welding head and the weld seam at the top of the workpiece 9, ensuring that the distance and position are appropriate, and adjusting the vertical distance between the bottom of the laser welding gun's welding head and the top of the workpiece 9 is greater than 2.5mm.

[0083] Then, loosen the bolt connecting the second adjusting block 5 and the height adjusting rod 3. After loosening, pull the height adjusting rod 3 upward to move it upward within the second adjusting block 5. At this time, the upward movement of the height adjusting rod 3 will cause the protective air support 1 to move upward at the same time, and the movement distance will be greater than 2.5mm, preferably much greater than 2.5mm. After the movement is complete, retighten the bolt connecting the second adjusting block 5 and the height adjusting rod 3.

[0084] Next, according to the actual welding needs, the welding head of the laser welding gun is lowered by 1.5mm-2.5mm using a robot. Since the distance between the bottom of the laser welding gun's welding head and the top of the workpiece 9, and the distance between the bottom of the protective gas shield 1 and the top of the workpiece 9, are both greater than 2.5mm, the bottom of the laser welding gun's welding head and the bottom of the protective gas shield 1 will not collide with the workpiece 9 during the descent. After the descent is completed, the bolt connecting the second adjusting block 5 and the height adjusting rod 3 is loosened again, and the height adjusting rod 3 is moved downwards until the bottom of the protective gas shield 1 is in contact with the surface of the workpiece 9. After stopping, the bolt connecting the second adjusting block 5 and the height adjusting rod 3 is tightened again.

[0085] Finally, the welding head of the laser welding gun is adjusted by the robot to return it to its original position (i.e., the position before it dropped 1.5mm-2.5mm). At this time, the distance between the bottom of the protective gas support 1 and the top of the workpiece 9 is 1.5mm-2.5mm, thus completing the vertical adjustment of the protective gas support 1.

[0086] Third, loosen the bolts connecting the first adjusting block 4 and the second connecting block 6, and adjust the position of the protective air support 1 laterally so that both the first and second air jet mechanisms are centered with the weld seam of the workpiece 9. After adjustment, retighten the bolts connecting the first adjusting block 4 and the second connecting block 6 to complete the adjustment of the centering of the protective air support 1.

[0087] Fourth, loosen the bolt connecting the second adjusting block 5 and the first adjusting block 4, and adjust the position of the protective air support shroud 1 along the sliding direction of the second adjusting block 5 on the first adjusting block 4, thereby adjusting the distance between the bottom of the inclined air outlet 14 and the light emission point of the laser welding gun. The adjustment range for the distance between the bottom of the inclined air outlet 14 and the light emission point of the laser welding gun is 3mm-5mm.

[0088] Next, in this embodiment, the thickness of workpiece 9 is 1mm-2mm, which is suitable for large spot welding. Therefore, the focal height of the laser welding gun can be adjusted, and the focal point can be adjusted to be above the weld seam of workpiece 9, i.e., in a positive defocus mode. The distance between the focal point and the weld seam of workpiece 9 (i.e., the defocus amount) is in the range of 3mm-6mm. After adjustment, the ends of the first air pipe 7 and the second air pipe 8 outside the protective air support cover 1 are connected to the external blower, and the external blower is activated, so that air can be blown onto the weld seam of workpiece 9 through the first jet mechanism and the second jet mechanism respectively.

[0089] Finally, the laser welding gun is activated, and the robot simultaneously moves the device along the weld seam direction of workpiece 9 to perform the welding work on workpiece 9. During the welding process, the robot can oscillate the laser welding gun's output point at a frequency of 80Hz and an amplitude of 0.6mm-1mm, i.e., use laser oscillation welding to weld the weld seam of workpiece 9. This can accommodate a weld seam gap of 0.2mm and a weld seam misalignment of 0.2mm at the weld seam of workpiece 9.

[0090] In this embodiment, the oscillation mode of laser oscillation welding can preferably be circular oscillation, which can further adapt to the gap and misalignment at the weld seam of workpiece 9, and better ensure good welding effect.

[0091] The above embodiments of this utility model can be combined with each other and have corresponding technical effects.

[0092] The above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A gas-shielded laser welding apparatus for niobium alloys in an atmospheric environment, characterized in that, The protective gas cover (1), the adjusting mechanism and the air jet assembly are included, wherein: The workpiece (9) to be welded is placed below the protective gas cover (1), and the weld of the workpiece (9) is arranged correspondingly to the protective gas cover (1); One end of the adjusting mechanism is installed on the protective gas cover (1), and the other end of the adjusting mechanism is provided with a laser welding gun of the laser welding device, and the light emitting point of the laser welding gun is arranged correspondingly to the weld of the workpiece (9); The air jet assembly is installed in the protective gas cover (1), and the air jet assembly is arranged correspondingly to the weld of the workpiece (9), and the air jet assembly is used to protect the molten metal in the welding process of the workpiece (9) and the weld metal in the high-temperature state in the welding process.

2. The apparatus for laser welding of niobium alloy in a gas atmosphere according to claim 1, wherein The adjusting mechanism includes a height-adjusting rod (3), the height-adjusting rod (3) is vertically arranged, the bottom end of the height-adjusting rod (3) is installed on the top end of the protective gas cover (1), the top of the height-adjusting rod (3) is bolted and slidably installed with a second adjusting block (5), the relative sliding direction between the second adjusting block (5) and the height-adjusting rod (3) is arranged along the length direction of the height-adjusting rod (3); the first adjusting block (4) is bolted and slidably installed on the second adjusting block (5), the relative sliding direction between the first adjusting block (4) and the second adjusting block (5) is horizontally arranged and arranged along the direction that the air jet assembly approaches or moves away from the light emitting point of the laser welding gun; the second connecting block (6) is bolted and slidably installed on the first adjusting block (4), the relative sliding direction between the second connecting block (6) and the first adjusting block (4) is horizontally arranged and perpendicular to the relative sliding direction between the first adjusting block (4) and the second adjusting block (5), and the laser welding gun of the laser welding device is detachably installed at the end of the second connecting block (6).

3. The apparatus according to claim 2, wherein The top end of the protective gas cover (1) is rotatably installed with a first connecting block (2), the end of the first connecting block (2) is rotatably connected with the bottom end of the height-adjusting rod (3), and the height-adjusting rod (3) is installed on the top end of the protective gas cover (1) through the first connecting block (2).

4. The apparatus according to claim 2, wherein The height-adjusting rod (3) is a multi-prism structure.

5. The apparatus for laser welding of niobium alloy in an atmosphere according to claim 1, wherein The air jet assembly includes a first air jet mechanism and a second air jet mechanism, the first air jet mechanism is located between the light emitting point of the laser welding gun and the second air jet mechanism, and the first air jet mechanism and the second air jet mechanism are arranged correspondingly to the weld of the workpiece (9); the first air jet mechanism is used to protect the molten metal in the welding process of the workpiece (9), and the second air jet mechanism is used to protect the weld metal in the high-temperature state in the welding process of the workpiece (9).

6. The apparatus for laser welding of niobium alloy in a gas atmosphere according to claim 5, wherein The first air jet mechanism comprises an oblique air outlet hole (14) formed in the bottom end of the protective gas bell (1), which is located between the light emitting point of the laser welding gun and the second air jet mechanism; the bottom end of the oblique air outlet hole (14) is arranged corresponding to the weld of the workpiece (9), the protective gas bell (1) is provided with a first air passage, one end of the oblique air outlet hole (14) is communicated with one end of the first air passage, and the other end of the first air passage is communicated with the external air blowing device.

7. The apparatus according to claim 6, wherein The angle between the bottom end of the oblique air outlet hole (14) and the bottom end of the protective gas bell (1) is or basically is 45°.

8. The apparatus according to claim 6, wherein The second air jet mechanism comprises a third air pipe (11) installed in the protective gas bell (1), the protective gas bell (1) is provided with a second air passage, one end of the second air passage is communicated with one end of the third air pipe (11), and the other end of the second air passage is communicated with the external air blowing device; the bottom end of the protective gas bell (1) is provided with an air passage groove, the oblique air outlet hole (14) is located between the air passage groove and the light emitting point of the laser welding gun, the top end of the air passage groove is communicated with the third air pipe (11), the first hole plate (10) is fixedly installed on the inner wall of the bottom end of the air passage groove, the first hole plate (10) is arranged corresponding to the weld of the workpiece (9), and the air passage groove and the third air pipe (11) are independently arranged with the oblique air outlet hole (14).

9. The apparatus according to claim 8, wherein The third air pipe (11) is located at the top end of the air passage groove, and a second hole plate (13) is arranged between the third air pipe (11) and the first hole plate (10), and the inner wall of the air passage groove is fixedly connected with the side wall of the second hole plate (13).

10. The apparatus for laser welding of niobium alloy in a gas atmosphere according to claim 9, wherein The third air pipe (11) is communicated with a plurality of branch air pipes (12) near one end of the oblique air outlet hole (14), and the branch air pipes (12) are independently arranged with the oblique air outlet hole (14); a plurality of air holes corresponding to the holes in the second hole plate (13) are formed in the third air pipe (11) and the branch air pipes (12), a small pipe is arranged between each hole in the second hole plate (13) and the corresponding air hole, and both ends of each small pipe are fixedly connected with the second hole plate (13) and the corresponding air hole; the third air pipe (11) and the branch air pipes (12) are communicated with the air passage groove through the air holes and the small pipes.

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