Welding method for plug-in type shaft plate structure

Abstract

The invention provides a welding method for a plug-in type shaft plate structure, which is used for connecting a plate and a shaft, and comprises the following steps of: 1, forming a groove on the plate; secondly, the shaft is inserted into the groove; thirdly, laser welding equipment is provided, a single wire feeding mode is adopted, and spot welding is conducted on at least one position on the circumference of the bottom of the groove; fourthly, the laser welding equipment is utilized, a double-wire-feeding mode is adopted, welding operation is conducted around the shaft at the bottom of the groove, and therefore a bottoming welding seam is formed at the bottom of the groove; and fifthly, welding is conducted on the bottoming weld joint formed in the fourth step through the laser welding equipment in a double-wire-feeding mode and a swing mode, and therefore a filling layer and a covering layer of the weld joint are formed. A high-quality shaft plate welding structure can be achieved.

Description

Technical Field

[0001] The invention relates to the field of welding, in particular to the welding of an inserted shaft plate structure. Background Art

[0002] At present, thick plate high-strength steel welding structures are widely used in large equipment such as engineering machinery, ships, and heavy machinery. The main forms of steel plate welding are plate-to-plate butt joints and corner joints. Inserted shaft plate welding structures also have many applications in industrial production, such as shaft sleeve through-plate in engineering machinery. The inserted shaft plate welding structure is the same as the thick plate high-strength steel welding structure, and also needs to achieve a high welding strength. However, due to its unique structure, it is more difficult than the thick plate high-strength steel welding structure. In addition, due to the uneven assembly gap between the plate and the shaft, and the small welding space, there are problems such as difficulty in grinding welds and welds, incomplete root penetration, and back weld undercutting, which seriously affect the quality of welded structural parts and the progress of engineering production.

[0003] In the prior art, patent document CN202110283924.7 relates to a welding method and device for a single-sided V-groove weldment with uneven groove gap, and discloses a welding machine, a welding gun, and a welding gun tracking device, which is characterized in that a welding gun A and a welding gun B are installed on the welding gun tracking device, the molten pools of the welding gun A and the welding gun B are fused together, and the distance between the welding wire end A of the welding gun A and the welding wire end B of the welding gun B is adjustable; a flexible welding pad is attached to the back of the welding surface; the position of the welding wire contact point on the weldment is determined, and the angle between the welding wire of the welding gun A and the weldment is adjusted by the A fine-tuning mechanism, and the welding wire is aligned with the position of the welding wire contact point; the angle between the welding wire of the welding gun B and the weldment is adjusted by the B fine-tuning mechanism, and the welding wire is aligned with the position of the welding wire contact point. The present invention enables automatic welding to be used for base welding, and is cheap and improves welding efficiency. This patent installs two guns on the welding gun tracking device to adjust the welding gun angle according to different gaps. However, in actual application, this method is easily limited in the welding gun position due to the difference in groove angles and structural parts, and can only be used for welding special structural parts.

[0004] Patent document CN201910469271.4 proposes a single-sided V-groove multi-layer multi-pass welding path planning method and system, including: modeling the weld arrangement of the single-sided V-groove angle joint on the right side; the weld planning adopts an equal height filling strategy, the cross-section of the base weld is fitted with a right-angled triangle, the first weld of each layer of the second layer and above is fitted with a right-angled trapezoid, the last weld is fitted with a trapezoid, and the remaining welds are fitted with a rhombus; determine the number of layers and passes, welding gun position, welding gun inclination and welding gun swing of the single-sided V-groove welding; perform path planning based on the determined welding gun posture to achieve single-sided V-groove multi-layer multi-pass welding. The present disclosure establishes a multi-layer multi-pass welding path planning model for single-sided V-groove, which requires the user to determine the height of the base weld and the filling weld, and the model can be used to calculate the position, posture, swing, welding process parameters and other results of the welding gun. This patent carries out path planning for single-sided V-groove welds. Although the model can be used to calculate the welding gun's position, posture, swing, welding process parameters and other results, it cannot solve welding defects such as incomplete root penetration and back undercut.

[0005] Patent document CN202211059368.6 provides a method for welding medium and thick plates, which includes opening a single-sided V-shaped groove on the medium and thick plate structural member to be welded, removing the single-sided V-shaped groove surface of the medium and thick plate structural member to be welded and impurities within the range of 20mm-30mm around the single-sided V-shaped groove; setting a pad on the back of the plate to be welded, and preheating the medium and thick plate structural member to the first set temperature; performing deep penetration base welding; according to the construction convenience of the medium and thick plate structural member to be welded, at least one of submerged arc welding and CO2 gas shielded welding is selected to perform the filling and capping welding of the medium and thick plate structural member to be welded, and after welding is completed, the medium and thick plates to be welded of different materials are subjected to post-weld treatment. The technical solution of the present invention, aimed at the welding amount and the efficiency problem of base welding of a certain type of medium and thick plate, can reduce the welding amount and the number of welds, perform single-sided welding and double-sided forming, and improve the efficiency of base welding and overall welding. This patent provides a V-shaped butt weld for plate-to-plate butt welding, and the welding method provided is to achieve welding with a gasket on the back side, but there is no introduction to the annular weld for the shaft-plate combination.

[0006] Therefore, there is a need for an improved technique for achieving high quality welding of axle plates. Summary of the invention

[0007] The object of the present invention is to solve the above technical problems and provide a welding method for an inserted shaft plate structure, which can adapt to the uneven assembly gap between the plate and the shaft and achieve high-quality welding of the shaft plate.

[0008] Another object of the present invention is to provide a welding method for an inserted shaft-plate structure, which is suitable for a smaller welding space between the plate and the shaft.

[0009] Another object of the present invention is to provide a welding method for an inserted shaft plate structure, which does not require grinding after welding.

[0010] Another object of the present invention is to provide a welding method for an inserted shaft plate structure, which achieves a wide molten pool and high penetration effect, and improves weld quality and welding efficiency.

[0011] The present invention provides a welding method for an inserted shaft-plate structure, which is used to connect a plate and a shaft, and the welding method comprises the following steps: a first step, opening a groove on the plate, the diameter of the groove being larger than the diameter of the shaft to be connected; a second step, inserting the shaft into the groove and keeping the position of the shaft in the groove unchanged; a third step, providing laser welding equipment, adopting a single wire feeding mode, spot welding at at least one position on the circumference of the bottom of the groove, thereby fixing the position of the shaft in the groove; a fourth step, using the laser welding equipment, adopting a double wire feeding mode, performing a welding operation around the shaft at the bottom of the groove, thereby forming a base weld at the bottom of the groove; and a fifth step, using the laser welding equipment, adopting a double wire feeding mode, and adopting a swinging method, welding on the base weld formed in the fourth step, thereby forming a filling layer and a cover layer of the weld.

[0012] In the third step, the laser single wire spot welding method can well adapt to the uneven narrow gap between the blunt edge of the shaft and the groove. In addition, due to the large penetration depth of laser welding, the weld spot formed is small and the connection strength is large, and no subsequent grinding process is required. This avoids the problem of subsequent direct welding at the large weld spot position and poor weld quality in the traditional shaft-plate welding method because the grinder cannot penetrate into the small groove position to grind the weld spot.

[0013] In the fourth step, the laser double-wire welding method is used to effectively solve the problems of poor root penetration and poor back weld formation caused by uneven assembly gaps. By adjusting the laser welding parameters, a full-penetration fillet weld without a backing can be achieved on the back, and the effect of single-sided welding and double-sided forming can be achieved. The double-wire diameter coverage range is used to solve defects such as weld leakage caused by large gaps.

[0014] In the five steps, the oscillating laser double-wire welding filling and capping technology is used to achieve a wide molten pool and high penetration effect, effectively reducing the number of welding times and ensuring 100% penetration of the weld. Compared with traditional welding processes, the weld quality and welding efficiency are greatly improved.

[0015] Preferably, the plate is a metal plate, and the thickness of the plate is not greater than 20 mm.

[0016] Preferably, in a cross section along the axis of the shaft, the boundary of the groove on one side forms a single-sided V-shape with the corresponding side edge of the shaft, preferably, the angle α of the single-sided V-shape is between 30°-40°, preferably, the groove includes a blunt edge at its lower end, preferably, the height of the blunt edge is between 0-1mm, preferably, the spot welding is performed at the blunt edge, preferably, the minimum diameter of the groove is 0-1mm larger than the diameter of the shaft.

[0017] Preferably, in the second step, the surface of the plate is processed to remove surface oil, dirt, impurities, etc. Preferably, in the second step, the position of the shaft in the groove is maintained by mechanical clamping.

[0018] Preferably, the following welding parameters are used in the third step: laser power 0.8 to 1 kW, defocusing amount -1 to +1, wire feeding speed 70 to 100 mm / s.

[0019] Preferably, in the third step, spot welding is performed at two, three or four positions equidistantly distributed on the circumference of the bottom of the groove.

[0020] Preferably, in the fourth step, a circle of welding is performed around the shaft to form a circle of base weld.

[0021] Preferably, the bottom weld fills the gap between the blunt edge and the shaft and is higher than the height of the blunt edge.

[0022] Preferably, the diameter of the welding wire used in the fourth step is larger than the gap between the shaft and the bottom of the groove, for example, the diameter of the welding wire is 1.0-1.6 mm. Preferably, the welding wires of the same diameter are used in the third, fourth and fifth steps.

[0023] Preferably, in the fourth step, the angle of the laser welding equipment is adjusted so that the double welding wire is located at the center of the gap between the shaft and the groove.

[0024] Preferably, in the fourth step, the laser welding adopts the following parameters: laser power 1.5 to 2.5 kW, defocusing amount -1 to +1, wire feeding speed 70 to 100 mm / s.

[0025] Preferably, in the fifth step, the filling layer and the covering layer are formed by a linear swing method or a circular swing method. Preferably, the swing frequency is 1 to 5 Hz and the swing amplitude is 2 to 3 mm.

[0026] Preferably, the following welding parameters are used in the fifth step: laser power 2 to 3 kW, defocusing amount -1 to +1, wire feeding speed 80 to 120 mm / s.

[0027] Preferably, laser arc hybrid welding equipment is used instead of the laser welding equipment.

[0028] Preferably, a protective gas is used in the third to fifth steps, preferably pure argon is used as the protective gas, and preferably, the flow rate of the protective gas is 12 to 20 L / min. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings illustrate preferred embodiments of the present invention, in which:

[0030] Figure 1 A schematic cross-sectional view of an inserted shaft-plate structure to be welded together is shown, showing the uneven gap between the shaft and the plate hole;

[0031] Figure 2 yes Figure 1 A top view of the inserted shaft plate structure, showing the offset position of the shaft in the plate hole;

[0032] Figure 3 A schematic diagram of implementing a welding method according to the present application is shown;

[0033] Figure 4 A schematic cross-sectional view of the axle plate structure after the third and fourth steps are completed according to the welding method of the present application is shown;

[0034] Figure 5 A schematic cross-sectional view showing the shaft plate structure obtained after the fifth step is completed according to the welding method of the present application; and

[0035] Figure 6 The welding tracks without swinging and the swinging tracks in different ways in the fifth step of the welding method according to the present application are respectively shown. DETAILED DESCRIPTION

[0036] The present application will be described below with reference to the accompanying drawings, wherein the accompanying drawings illustrate several embodiments of the present application. However, it should be understood that the present application can be presented in a variety of different ways and is not limited to the embodiments described below; in fact, the embodiments described below are intended to make the disclosure of the present application more complete and fully explain the scope of protection of the present application to those skilled in the art. It should also be understood that the embodiments disclosed herein can be combined in various ways to provide more additional embodiments.

[0037] Welding method of the present application

[0038] The present application provides a welding method for an inserted shaft plate structure, which is used to connect the structure with sufficient strength. Figure 1The schematic diagram shows a plate 1 and a shaft 2, wherein the plate 1 has a thickness of no more than 20 mm and is generally made of metal material, such as a steel plate, and the shaft 2 can be hollow or solid. In the case of a hollow shaft, the wall thickness of the hollow shaft should be thick enough to meet the requirements of welding operation and weld strength, etc. The various steps of the welding method are described in detail below.

[0039] See first Figure 1 , shows a cross-sectional schematic diagram of an inserted shaft plate structure to be welded. According to the welding method of the present application, in the first step, a groove 3 is formed on the plate 1, the minimum diameter of which is larger than the diameter of the shaft 2 to be connected, so as to allow the shaft 2 to pass through the groove 3.

[0040] In one embodiment, Figure 1 In the cross section along the axis of the shaft 2 shown, the groove 3 is shown as a single-sided V-shaped groove on one side of the shaft 2, that is, Figure 1 As shown, the groove 3 forms a V-shape at the boundary of one side with the corresponding side of the shaft 2. In one embodiment, the groove 3 includes a blunt edge 5 at its lower end. In one embodiment, the height of the blunt edge 5 of the groove 3 is between 0-1 mm. In one embodiment, the groove angle α of the single-sided V-shaped groove 3 is between 30°-40°. In one embodiment, the minimum diameter of the single-sided V-shaped groove 3 (i.e., the diameter at the blunt edge 5) is 0-1 mm larger than the diameter of the shaft 2.

[0041] In the second step, the surface of the plate 1 is processed to remove surface oil, dirt and impurities, and the shaft 2 can be inserted into the groove 3 by, for example, mechanical clamping, and the position of the shaft 2 in the groove 3 is kept unchanged.

[0042] like Figure 2 As shown, in actual operation, the position of the shaft 2 in the groove 3 is usually offset, that is, the shaft 2 and the groove 3 are not concentric, so the gap between the shaft 2 and the groove 3 is usually not evenly distributed. Figure 1 and 2 As described above, when the groove 3 is formed, since the diameter of the blunt edge 5 of the groove 3 is set to be 0-1 mm larger than the diameter of the shaft 2, the gap between the narrowest boundary of the groove 3 (the blunt edge 5) and the shaft 2 usually varies in the range of 0-1 mm. As described above, this variable narrow gap makes it difficult to weld the shaft plate structure.

[0043] In order to overcome the difficulties caused by the changing narrow gap between the shaft and the groove, the present application uses laser welding equipment and welding wire to achieve the welding of the shaft-plate structure. Laser welding uses high-energy laser pulses to highly concentrate light energy and heat energy in a very small spot, instantly melting the welding wire and the parts to be welded. The energy of the laser radiation diffuses to the inside of the material through heat conduction, and the material is melted to form a specific molten pool. Laser welding is mainly aimed at the welding of thin-walled materials and precision parts. In the present application, laser welding equipment is used to weld the shaft-plate structure, thereby utilizing the above-mentioned characteristics of laser welding to solve the problem of welding connection caused by the changing narrow gap of the shaft-plate structure.

[0044] According to the welding method of the present application, in the third step, laser welding equipment is used in a single wire feeding mode to perform spot welding at the bottom of the groove 3 (the blunt edge 5), and spot welding is performed at at least one position on the circumference of the bottom of the groove 3, thereby fixing the position of the shaft 2 in the groove 3.

[0045] In this step, the laser single wire spot welding method can well adapt to the uneven narrow gap between the blunt edge of the shaft and the groove, and because the laser welding has a large penetration depth, the weld spot formed is small and the connection strength is large, and no subsequent grinding process is required, thus avoiding the problem of subsequent direct welding at the large weld spot position and resulting in poor weld quality due to the inability of the grinder to penetrate into the small groove position to grind the weld spot in the traditional shaft-plate welding method.

[0046] In one embodiment, the spot welding laser power is 0.8-1KW, the defocusing amount is -1-+1, the wire feeding speed is 70-100mm / s, and the diameter of the welding wire is 1.0-1.6mm. In one embodiment, spot welding is performed at two, three or four positions equidistant on the circumference of the bottom of the groove 3.

[0047] In the fourth step, the laser welding equipment is used to perform welding operation around the shaft 2 at the bottom of the groove 3 in a double wire feeding mode, so as to form a groove at the bottom of the groove 3 as shown in FIG. Figure 4 The bottoming weld 7 shown covers the welding spot formed in the third step.

[0048] In this step, the laser double-wire welding method is used to effectively solve the problems of poor root penetration and poor back weld formation caused by uneven assembly gaps. By adjusting the laser welding parameters, a full penetration fillet weld without a backing can be achieved on the back, and the effect of single-sided welding and double-sided forming can be achieved. The double-wire diameter coverage range is used to solve defects such as weld leakage caused by large gaps.

[0049] In one embodiment, a circle is welded around the shaft 2 to form a circle of backing weld 7. In one embodiment, the backing weld 7 fills the groove 5 and is higher than the height of the groove 5. In one embodiment, the diameter of each welding wire used is larger than the gap between the shaft 2 and the bottom of the groove 3, for example, the diameter of each welding wire is 1.0-1.6 mm. Figure 3 FIG. 4 is a schematic diagram showing a laser welding device 4 and a double welding wire 6. In one embodiment, by adjusting the angle of the laser welding device 4, the double welding wire 6 is located at the center of the gap between the shaft 2 and the groove 3. Figure 3 In one embodiment, the laser welding adopts the following parameters: laser power 1.5-2.5KW, defocusing amount -1-+1, wire feeding speed 70-100mm / s.

[0050] In the fifth step, the laser welding equipment is used in a double wire feeding mode and a swinging manner to perform welding on the base weld 7 formed in the fourth step, thereby forming a filler layer 8 and a cover layer 9 of the weld. The swinging manner is used to achieve a wide molten pool effect, effectively reducing the number of welding times.

[0051] In this step, the oscillating laser double-wire welding filling and capping technology is used to achieve a wide molten pool and high penetration effect, effectively reducing the number of welding times and ensuring 100% penetration of the weld, greatly improving the weld quality and welding efficiency compared to traditional welding processes.

[0052] Figure 6 A welding path 10 without oscillation, a welding path 11 with a linear oscillation and a welding path 12 with a circular oscillation are shown.

[0053] In one embodiment, a linear swing method is used (see Figure 6 The filling layer 8 and the cover layer 9 are formed by welding the welding track 11. In one embodiment, a circular swing method (see Figure 6 The filling layer 8 and the capping layer 9 are formed by welding the track 12 in the middle. In one embodiment, the oscillation frequency is 1 to 5 Hz, and the oscillation amplitude is 2 to 3 mm. In one embodiment, the diameter of each welding wire is 1.0-1.6 mm. In one embodiment, the following welding parameters are used: laser power 2 to 3 KW, defocusing amount -1 to +1, and wire feeding speed 80 to 120 mm / s.

[0054] In this step, laser arc hybrid welding equipment can be used instead of laser welding equipment, and the stability of the arc can be improved by using the laser induction principle, thereby improving the quality of the interlayer weld. At the same time, the arc swing method can also be used to weld the machine, thereby improving the welding efficiency.

[0055] In the third to fifth steps of the above welding method, a shielding gas is used. In one embodiment, the flow rate of the shielding gas used is set to 12 to 20 L / min. In one embodiment, pure argon is used as the shielding gas.

[0056] In one embodiment, the welding wires used in the third step, the fourth step, and the fifth step have the same diameter.

[0057] Table 1 gives examples of ranges for some welding parameters for the welding method described above.

[0058] Table 1

[0059]

[0060] Beneficial effects of this application

[0061] Compared with traditional welding, spot welding has large weld spots, small penetration, low connection strength, and the grinder cannot penetrate into the small groove position to grind the weld spots, which leads to subsequent direct welding at the large weld spot position, resulting in poor weld quality, and poor penetration during base welding, resulting in incomplete penetration and poor forming on the back side. The welding method described in the present application uses highly penetrating laser welding for spot welding, which has a large penetration depth and small weld spots. No grinding is required after spot welding, and single-sided welding and double-sided forming effects are achieved through laser double-wire welding during the base welding process. At the same time, a laser double-wire welding method with swinging technology is used for filling and capping welding, which achieves a wide molten pool and high penetration effects, effectively reduces the number of welding times, ensures 100% penetration of the weld, and greatly improves the weld quality and welding efficiency compared to traditional welding processes.

[0062] Having provided the description of the preferred embodiments, it will be apparent that modifications may be made by a person skilled in the art without thereby departing from the scope of the invention as defined by the following claims.

Claims

1. A welding method for an inserted shaft-plate structure, used for connecting a plate (1) and a shaft (2), the welding method comprising the following steps: The first step is to open a groove (3) on the plate (1), wherein the diameter of the groove (3) is larger than the diameter of the shaft (2) to be connected; The second step is to insert the shaft (2) into the groove (3) and keep the position of the shaft (2) in the groove (3) unchanged; The third step is to provide a laser welding device, adopt a single wire feeding mode, and perform spot welding at at least one position on the circumference of the bottom of the groove (3); The fourth step is to use the laser welding equipment in a double wire feeding mode to perform a welding operation around the shaft (2) at the bottom of the groove (3), thereby forming a base weld (7) at the bottom of the groove (3); as well as In the fifth step, the laser welding equipment is used in a double wire feeding mode and an oscillating manner to perform welding on the base weld (7) formed in the fourth step, thereby forming a filling layer (8) and a cover layer (9) of the weld.

2. The welding method according to claim 1, characterized in that: The plate (1) is a metal plate, and the thickness of the plate is not greater than 20 mm.

3. The welding method according to claim 1 or 2, characterized in that: In a cross section along the axis of the shaft (2), the boundary of the groove (3) on one side forms a single-sided V-shape with the corresponding side of the shaft, Preferably, the angle (α) of the single-sided V-shape is between 30° and 40°. Preferably, the groove (3) comprises a blunt edge (5) at its lower end, preferably, the height of the blunt edge is between 0 and 1 mm, preferably, the spot welding is performed at the blunt edge (5), Preferably, the minimum diameter of the groove (3) is 0-1 mm larger than the diameter of the shaft (2).

4. The welding method according to any one of claims 1 to 3, characterized in that: In the second step, the surface of the plate (1) is treated to remove surface oil, dirt, and impurities. Preferably, in the second step, the position of the shaft (2) in the groove (3) is maintained by mechanical clamping.

5. The welding method according to any one of claims 1 to 4, characterized in that: In the third step, the following welding parameters are used: laser power 0.8 to 1 KW, defocusing amount -1 to +1, and wire feeding speed 70 to 100 mm / s.

6. The welding method according to any one of claims 1 to 5, characterized in that: In the third step, spot welding is performed at two, three or four positions equidistantly distributed on the circumference of the bottom of the groove (3).

7. The welding method according to any one of claims 1 to 6, characterized in that: In the fourth step, a circle of welding is performed around the shaft (2) to form a circle of base weld (7).

8. The welding method according to any one of claims 1 to 7, characterized in that: The bottom weld (7) fills the gap between the blunt edge (5) and the shaft (2) and is higher than the height of the blunt edge (5).

9. The welding method according to any one of claims 1 to 8, characterized in that: The diameter of the welding wire used in the fourth step is larger than the gap between the shaft (2) and the bottom of the groove (3). For example, the diameter of the welding wire is 1.0-1.6 mm. Preferably, the welding wire of the same diameter is used in the third, fourth and fifth steps.

10. The welding method according to any one of claims 1 to 9, characterized in that: In the fourth step, the angle of the laser welding device (4) is adjusted so that the double welding wire (6) is located at the center of the gap between the shaft (2) and the groove (3).

11. The welding method according to any one of claims 1 to 10, characterized in that: In the fourth step, the laser welding adopts the following parameters: laser power 1.5 to 2.5 KW, defocusing amount -1 to +1, wire feeding speed 70 to 100 mm / s.

12. The welding method according to any one of claims 1 to 11, characterized in that: In the fifth step, the filling layer and the covering layer are formed by a linear swing method or a circular swing method. Preferably, the swing frequency is 1 to 5 Hz and the swing amplitude is 2 to 3 mm.

13. The welding method according to any one of claims 1 to 12, characterized in that: In the fifth step, the following welding parameters are used: laser power 2 to 3 KW, defocusing amount -1 to +1, and wire feeding speed 80 to 120 mm / s.

14. The welding method according to any one of claims 1 to 13, characterized in that: A laser arc hybrid welding device is used to replace the laser welding device.

15. The welding method according to any one of claims 1 to 14, characterized in that: In the third to fifth steps, a protective gas is used, preferably pure argon gas is used as the protective gas, and preferably, the flow rate of the protective gas is 12 to 20 L / min.

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