Process for welding cylinder part and sheet metal part

Abstract

The technology comprises the following steps that S1, a Z-shaped sheet metal part is prepared, and an annular notch is formed in the upper surface, where a first table top is located, of the Z-shaped sheet metal part; s2, a first chamfer is formed in the outer edge of an annular notch of the Z-shaped sheet metal part, and meanwhile a second chamfer is formed in the outer edge of the bottom contact face where the cylinder part is located; s3, the Z-shaped sheet metal part and the cylinder part are subjected to surface treatment and then preheated at the temperature of 120-150 DEG C; s4, coating a material layer on the annular notch of the Z-shaped sheet metal part and the contact surface of the cylinder part, and then embedding the cylinder part into the annular notch in a laser electric welding mode and welding and fixing the cylinder part; and S4, the connecting positions of the inner side and the outer side where the column part and the Z-shaped sheet metal part are located are filled with Sn welding materials, and Sn welding operation is conducted. According to the Z-shaped sheet metal part welding structure, the annular notch of the Z-shaped sheet metal part is precisely designed to be matched with the cylinder part, effective fixing is achieved, space is reserved for Sn welding materials, and the stability and reliability of the welding structure are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of metal plate welding, and in particular relates to a process for welding a column part and a sheet metal part. Background Art

[0002] Shaft parts are one of the common rotating parts in motors. They play the role of supporting and transmitting torque in motors. The design and manufacturing quality of shaft parts directly affect the performance and life of the motor. They are usually used at the ends of motors to fix and connect other components. However, there are bottlenecks in the connection process of shaft parts, and it is difficult to ensure strength and dimensional stability. Although molecular diffusion welding can form a connection, the welding pressure, including the weight of the welder, is too high, which can easily cause product deformation; and the parallelism of the product surface is unstable during welding, so the dimensional quality cannot be guaranteed. Given that the requirements for pull-out strength of such products are relatively loose, more attention is paid to stable connections in the axial direction to fully guarantee the fixing performance of the entire product.

[0003] The traditional welding method uses Ag solder molecular diffusion welding. This silver-based solder has a relatively high melting point and is suitable for applications that require welding at higher temperatures.

[0004] In the Chinese patent application publication number CN111774940A, a metal sheet welding process is disclosed. The grinding equipment used in this process includes a support frame, on which a motor is installed, and a grinding roller is fixedly connected to the end of the output shaft of the motor; a support table is fixedly connected to the support frame at the bottom of the grinding roller, and a cylindrical groove is opened on the top of the support table; this method connects a push rod that can be pushed by a No. 1 hydraulic rod to the bottom of the workbench, but in actual use, after the above welding method is used, it is easy to fall off, the firmness is not strong, and the application scenarios of the welded products are limited. Summary of the invention

[0005] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a process for welding a column part to a sheet metal part, which solves the above-mentioned technical problems existing in the prior art.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] A process for welding a column part to a sheet metal part comprises the following steps:

[0008] S1. Prepare a Z-shaped sheet metal part, wherein the Z-shaped sheet metal part comprises a first table, a second table and a connector, wherein the first table and the second table are integrally formed by the connector, and the first table and the second table are arranged in parallel, and an annular notch is provided on the upper surface where the first table is located, so that the depth of the annular notch is 0.5-2 mm lower than the upper surface where the first table is located, and the width is 0.5-1 mm larger than the annular outer diameter of the column part to be welded;

[0009] S2. A first chamfer is formed on the outer edge of the annular notch of the Z-shaped sheet metal part, and a second chamfer is formed on the outer edge of the bottom contact surface where the column part is located;

[0010] S3, performing surface treatment on the Z-shaped sheet metal parts and the column parts, and then preheating them at a temperature of 120 to 150° C.;

[0011] S4, coating a material layer on the annular notch of the Z-shaped sheet metal and the contact surface of the column part, and then embedding the column part into the annular notch by laser welding and welding it to fix it;

[0012] S5. The inner and outer connecting parts between the column part and the Z-shaped sheet metal part are filled with Sn welding materials, and Sn welding operations are performed.

[0013] Furthermore, the angle between the first chamfer and the horizontal direction is 30-45 degrees;

[0014] The angle between the second chamfer and the horizontal direction is 45-60 degrees.

[0015] Furthermore, ribs protruding outwards in a plurality of groups are distributed along the radial direction where the first chamfer and the second chamfer are located, so that when the column part is embedded in the annular groove, the ribs on the first chamfer and the ribs on the second chamfer are distributed alternately.

[0016] Furthermore, the ribs protrude from the surface by 0.1 to 0.2 mm and are distributed in an oblique strip shape as a whole.

[0017] Furthermore, the surface pretreatment operation in S3 specifically includes:

[0018] S301, immersing the column parts and Z-shaped sheet metal parts in alkali solution, and performing ultrasonic vibration treatment, and controlling the frequency between 20kHz and 40kHz;

[0019] S302, placing the column parts and Z-shaped sheet metal parts immersed in the alkali solution in a pickling solution, and simultaneously performing ultrasonic vibration treatment, and controlling the frequency between 40kHz and 60kHz;

[0020] S303, placing the pickled column parts and Z-shaped sheet metal parts in a drying furnace as a whole, and controlling the temperature to 150-180°C.

[0021] Furthermore, in S301, the alkali solution used is 8% to 10% NaOH solution, the treatment temperature is 40 to 60° C., and the treatment time is 10 to 15 minutes.

[0022] Furthermore, in S302, the pickling solution used is pickled in two steps, and the two-step pickling process is acid solution A and acid solution B respectively, wherein the acid solution A includes 300 mL / L hydrochloric acid, 60 mL / L phosphoric acid, 80 mL / L stabilizer, and 2 mL / L surfactant in a molar ratio of 15:3:4:0.1, and the column parts and the Z-shaped sheet metal parts are immersed at a temperature of 30-50°C for 1-2 minutes;

[0023] The acid solution B includes 300 mL / L hydrofluoric acid, 200 mL / L sulfuric acid, 240 mL / L hydrogen peroxide, 0.5 g / L pickling corrosion inhibitor, and 2 mL / L surfactant in a substance amount ratio of 15:10:12:0.1:0.2, and the column parts and the Z-shaped sheet metal parts are immersed at a temperature of 30-50° C. for 2-3 minutes.

[0024] Furthermore, the coating material layer is in powder or paste form, and is evenly coated on the annular notch and the contact surface of the column part, and is cured and dried before welding.

[0025] Furthermore, in S5, the welding temperature is 180-200° C., and the welding time is 160-180 s.

[0026] Furthermore, in S5, after the welding is completed, it is placed in a constant temperature box at 80-100° C. and left to stand for 12-24 hours.

[0027] Beneficial effects of the present invention:

[0028] 1. This application achieves effective fixation and reserves space for Sn welding materials by accurately designing the annular notch and column parts of the Z-shaped sheet metal, thereby improving the stability and reliability of the welding structure.

[0029] 2. The chamfer and rib structure designed in this application helps to reduce the dislocation and instability during welding, and reduce welding defects such as pores and cracks. The chamfer design helps to improve the distribution of welding stress, reduce welding stress concentration, and increase the fatigue life of the welded joint. At the same time, the design and distribution of the ribs reduce the instability during welding in the circumferential direction and enhance the overall strength of the welded structure.

[0030] 3. This application performs surface pretreatment (including alkali washing and pickling) and high-temperature drying on Z-shaped sheet metal parts and column parts to effectively remove grease, dirt and oxide layer on the surface, provide a clean and dry welding surface, and thus improve welding quality. The treatment after pickling can prevent the metal surface from re-oxidation and enhance the corrosion resistance of the welded structure.

[0031] 4. The post-welding treatment of this application (such as placing it in a constant temperature box for static rest) helps to eliminate welding stress and improve the overall performance of the welded joint. The application of laser welding and Sn welding technology improves welding accuracy and efficiency and shortens the production cycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below.

[0033] Figure 1 It is a schematic diagram of the overall process of an embodiment of the present invention;

[0034] Figure 2 It is a schematic diagram of the overall structure of workpiece welding forming according to an embodiment of the present invention;

[0035] Figure 3 It is a schematic diagram of the structure of a column part according to an embodiment of the present invention;

[0036] Figure 4 is a schematic diagram of the structure of a Z-shaped sheet metal part according to an embodiment of the present invention;

[0037] Figure 5 2 is a schematic diagram of the structure of the column part and the Z-shaped sheet metal part combined in an embodiment of the present invention;

[0038] Figure 6 It is a schematic cross-sectional structure diagram of a workpiece welded and formed according to an embodiment of the present invention;

[0039] Figure 7 Embodiment of the present invention Figure 6 Schematic diagram of part of the structure at A in the middle. DETAILED DESCRIPTION

[0040] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] like Figure 1 ,like Figure 2 As shown, an embodiment of the present invention provides a process for welding a column part and a sheet metal part, comprising the following steps:

[0042] S1, such as Figure 4 As shown, a Z-shaped sheet metal part 2 is prepared. The Z-shaped sheet metal part 2 includes a first table top 21, a second table top 22 and a connector 23. The first table top 21 and the second table top 22 are formed as a whole through the connector 23, and the first table top 21 and the second table top 22 are arranged in parallel. An annular groove 201 is opened on the upper surface where the first table top 21 is located, so that the depth of the annular groove 201 is 0.5-2mm lower than the upper surface where the first table top 21 is located, and the width is 0.5-1mm larger than the annular outer diameter size of the column part 1 to be welded. This cutting method can effectively fix the Z-shaped sheet metal part 2 and the column part 1, and reserve space for the Sn welding material 3 to form a gap filling, thereby increasing the contact surface with the Z-shaped sheet metal part 2 and the column part 1 at the same time.

[0043] S2. A first chamfer 202 is provided on the outer edge of the annular notch 201 of the Z-shaped sheet metal part 2, and the angle between the first chamfer 202 and the horizontal direction is 30-45 degrees; at the same time, a second chamfer 101 is provided on the outer edge of the bottom contact surface where the column part 1 is located, and the angle between the second chamfer 101 and the horizontal direction is 45-60 degrees. This chamfer design method can facilitate the transfer of the column part 1 to the annular notch 201 of the Z-shaped sheet metal part 2 (there will be a gap at the connection), effectively match the connection, reduce misalignment, ensure accurate matching during welding, and when the designed first chamfer 202 and the second chamfer 101 match each other, the welding stress distribution and welding quality can be improved. These angles help distribute heat and stress during welding.

[0044] like Figure 3 As shown, of course, in order to achieve the bonding between the Z-shaped sheet metal part 2 and the column part 1, ribs 11 protruding outward are distributed along the radial direction of the first chamfer 202 and the second chamfer 101, so that when the column part 1 is embedded in the annular groove 201, the ribs 11 on the first chamfer 202 and the ribs 11 on the second chamfer 101 are staggered, and the height of the ribs 11 protrudes from the surface by 0.1 to 0.2 mm, and the whole is distributed in an oblique strip shape. This distribution method can reduce the instability during welding in the circumferential direction.

[0045] S3, performing surface treatment on the Z-shaped sheet metal part 2 and the column part 1, wherein the surface pretreatment operation specifically includes:

[0046] S301, immerse the column part 1 and the Z-shaped sheet metal part 2 in alkali solution, and perform ultrasonic vibration treatment, and control the frequency between 20kHz and 40kHz; the alkali solution used is 8% to 10% NaOH solution, the treatment temperature is 40 to 60°C, and the treatment time is 10 to 15 minutes. Alkali washing can effectively remove grease, dirt, oil stains and other organic pollutants on the metal surface, which may affect the welding quality, especially during the formation of the molten pool and the solidification of the weld metal. And alkali washing can remove these oxide layers, revealing a clean metal surface, which is conducive to the wetting and flow of the solder during welding, and can reduce welding defects such as pores, slag inclusions and unfusion, thereby improving the quality and performance of the welded joint. Alkali washing can provide a clean surface and enhance the adhesion of subsequent coatings.

[0047] S302, placing the column part 1 and the Z-shaped sheet metal part 2 immersed in the alkali solution in a pickling solution as a whole, and simultaneously performing ultrasonic vibration treatment, and controlling the frequency to be between 40kHz and 60kHz;

[0048] The pickling liquid used is pickled in two steps, and the two-step pickling process is acid A and acid B respectively. Acid A includes 300mL / L hydrochloric acid, 60mL / L phosphoric acid, 80mL / L stabilizer, and 2mL / L surfactant in a molar ratio of 15:3:4:0.1, and the column part 1 and the Z-shaped sheet metal part 2 are immersed at a temperature of 30-50°C for 1-2 minutes; the acid A used is used to remove black skin and inclusions and part of the oxide skin at the welding point and weld.

[0049] Acid B includes 300mL / L hydrofluoric acid, 200mL / L sulfuric acid, 240mL / L hydrogen peroxide, 0.5g / L pickling corrosion inhibitor, and 2mL / L surfactant in a mass ratio of 15:10:12:0.1:0.2, and the column part 1 and the Z-shaped sheet metal part 2 are immersed at a temperature of 30-50°C for 2-3min; it is used to remove the gray film on the surface to make it nearly mirror-like bright. According to the above process, it is used to ensure the pickling effect while controlling the corrosion rate, ensuring the surface quality of the workpiece and the performance of subsequent processing. After the pickling is completed, on the surface to be welded where the column part 1 and the Z-shaped sheet metal part 2 are located, pickling can make the metal surface reach a uniform state, provide a consistent surface condition for welding, and facilitate the control of the welding process. Pickling can provide a clean surface and enhance the adhesion of subsequent coatings.

[0050] S303. Place the pickled column parts 1 and Z-shaped sheet metal parts 2 in a drying furnace as a whole and control the temperature to be 150-180°C. High-temperature drying can completely remove the pickling liquid and moisture remaining on the metal surface, prevent these liquids from generating pores, slag inclusions or other welding defects during welding, and prevent the metal surface from being re-oxidized in the air, especially in a humid environment, as the metal surface is prone to absorb moisture and re-form an oxide film in the air.

[0051] Then preheating is carried out at a temperature of 120 to 150°C. Preheating at this time can reduce the cooling rate of the welding area, reduce the thermal stress caused by rapid heating and cooling, thereby reducing welding deformation, and can reduce the hardness of the weld and heat-affected zone, prevent the formation of brittle martensitic structure, and help reduce welding defects such as pores and cracks, because preheating can reduce the temperature difference between the weld metal and the parent material, reduce the cooling rate, and thus reduce the formation of pores. Preheating can also improve the microstructure of the weld joint, improve its toughness and plasticity, thereby improving the overall performance of the weld joint. In the present application, preheating can reduce the need for post-heat treatment (such as stress relief heat treatment) required after welding, save time and cost, and help prevent the occurrence of cold cracks, especially when welding high-carbon steel or other materials that are prone to cold cracks.

[0052] S4, coating the material layer 301 on the annular notch 201 of the Z-shaped sheet metal part 2 and the contact surface of the column part 1, and then embedding the column part 1 into the annular notch 201 by laser welding and welding it to fix it. Figure 5 As shown, at this time, only the column part 1 is integrally welded to the annular notch 201 of the Z-shaped sheet metal part 2, and there is still a gap at its edge.

[0053] like Figure 6 , Figure 7 As shown, the coating material layer 301 is in powder or paste form, and is evenly coated on the annular notch 201 and the contact surface of the column part 1, and is cured and dried before welding. This laser welding method is to increase welding strength or protection, and improve welding accuracy and efficiency.

[0054] S5. Sn welding material 3 is filled at the inner and outer joints of the column part 1 and the Z-shaped sheet metal part 2, and Sn welding is performed. The Sn welding material 3 filled on both the inside and outside (used to fill the gap between the annular notch 201 and the column part 1) improves the welding accuracy and efficiency. The welding temperature is 180-200°C, the welding time is 160-180s, the drying furnace temperature is controlled at 150-180°C, and the welding temperature is 180-200°C to ensure that the material will not be damaged due to overheating. After welding is completed, place it in a constant temperature box at 80-100°C for 12-24 hours to ensure that the welding is sufficient and uniform.

[0055]

[0056]

[0057] As shown in Table 1 above, the chamfering cutting and Sn welding process of the present application greatly improves the compressive strength and tensile strength of the welded parts.

[0058] That is, in the present application, the thermal stress and structural strength during the welding process are taken into consideration, and the performance and service life of the welded joint are improved through the optimization of the design and process.

[0059] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. A process for welding a column part to a sheet metal part, characterized in that: The following steps are involved: S1. Prepare a Z-shaped sheet metal part (2), wherein the Z-shaped sheet metal part (2) comprises a first table surface (21), a second table surface (22) and a connector (23), wherein the first table surface (21) and the second table surface (22) are integrally formed by the connector (23), and the first table surface (21) and the second table surface (22) are arranged in parallel, and an annular notch (201) is provided on the upper surface where the first table surface (21) is located, so that the depth of the annular notch (201) is 0.5-2 mm lower than the upper surface where the first table surface (21) is located, and the width is 0.5-1 mm larger than the annular outer diameter of the columnar part (1) to be welded; S2. A first chamfer (202) is provided on the outer edge of the annular notch (201) of the Z-shaped sheet metal part (2), and a second chamfer (101) is provided on the outer edge of the bottom contact surface where the column part (1) is located; S3, performing surface treatment on the Z-shaped sheet metal part (2) and the column part (1), and then preheating them at a temperature of 120 to 150° C.; S4, coating the annular notch (201) of the Z-shaped sheet metal part (2) and the contact surface of the column part (1) with a material layer (301), and then embedding the column part (1) into the annular notch (201) and welding it to fix it by laser welding; S5. Sn welding material (3) is filled at the inner and outer connecting parts of the column part (1) and the Z-shaped sheet metal part (2), and Sn welding operation is performed.

2. The process for welding a column part to a sheet metal part according to claim 1, characterized in that: The angle between the first chamfer (202) and the horizontal direction is 30-45 degrees; The angle between the second chamfer (101) and the horizontal direction is 45-60 degrees.

3. The process for welding a column part to a sheet metal part according to claim 2, characterized in that: Several groups of ribs (11) protruding outward are distributed along the radial direction where the first chamfer (202) and the second chamfer (101) are located, so that when the column part (1) is embedded in the annular groove (201), the ribs (11) on the first chamfer (202) and the ribs (11) on the second chamfer (101) are distributed alternately.

4. The process for welding a column part to a sheet metal part according to claim 3, characterized in that: The height of the ribs (11) protrudes from the surface by 0.1 to 0.2 mm, and is distributed in the shape of oblique strips as a whole.

5. The process for welding a column part to a sheet metal part according to claim 1, characterized in that: The surface pretreatment operation in S3 specifically includes: S301, immersing the columnar component (1) and the Z-shaped sheet metal component (2) in an alkaline solution, and subjecting them to ultrasonic vibration treatment, with the frequency controlled between 20 kHz and 40 kHz; S302, placing the column part (1) and the Z-shaped sheet metal part (2) immersed in the alkali solution in a pickling solution as a whole, and simultaneously performing ultrasonic vibration treatment, and controlling the frequency to be between 40 kHz and 60 kHz; S303, placing the pickled column part (1) and the Z-shaped sheet metal part (2) in a drying furnace as a whole, and controlling the temperature to be 150-180°C.

6. The process for welding a column part to a sheet metal part according to claim 5, characterized in that: In the S301, the alkali solution used is 8% to 10% NaOH solution, the treatment temperature is 40 to 60° C., and the treatment time is 10 to 15 minutes.

7. The process for welding a column part to a sheet metal part according to claim 5, characterized in that: In S302, the pickling solution used is pickled in two steps, and the two pickling processes are acid solution A and acid solution B respectively. The acid solution A includes 300 mL / L hydrochloric acid, 60 mL / L phosphoric acid, 80 mL / L stabilizer, and 2 mL / L surfactant in a molar ratio of 15:3:4:0.1, and the column part (1) and the Z-shaped sheet metal part (2) are immersed at a temperature of 30-50°C for 1-2 minutes; The acid solution B comprises 300 mL / L hydrofluoric acid, 200 mL / L sulfuric acid, 240 mL / L hydrogen peroxide, 0.5 g / L pickling corrosion inhibitor, and 2 mL / L surfactant in a molar ratio of 15:10:12:0.1:0.2, and the column part (1) and the Z-shaped sheet metal part (2) are immersed at a temperature of 30 to 50° C. for 2 to 3 minutes.

8. The process for welding a column part to a sheet metal part according to claim 1, characterized in that: The coating material layer (301) is in powder or paste form and is evenly coated on the annular notch (201) and the contact surface of the column part (1). After being cured and dried, welding is performed.

9. The process for welding a column part to a sheet metal part according to claim 1, characterized in that: In S5, the welding temperature is 180-200° C., and the welding time is 160-180 seconds.

10. The process for welding a column part to a sheet metal part according to claim 1, characterized in that: In S5, after welding is completed, the welding is placed in a constant temperature box at 80-100° C. and left to stand for 12-24 hours.

Images