A system and method for underwater local dry laser filler wire welding

Abstract

This disclosure provides an underwater localized dry laser wire-filled welding system and method, belonging to the field of underwater welding technology. It includes a drainage hood, an air supply device, a wire feeding device, a laser welding device, and a control system. The drainage hood is installed underwater, covering the underwater area to be welded. The control system is electrically connected to the air supply device, the wire feeding device, and the laser welding device. It also includes an underwater drive device, with the drainage hood fixed to it. The underwater drive device is electrically connected to the control system. After underwater localized dry welding is completed, this disclosure uses a laser beam to remelt the weld, improving the weld surface microstructure, optimizing weld formation performance, and solving problems such as accelerated weld cooling rate, incomplete spread, poor fusion, and intergranular corrosion in the underwater environment. This effectively improves the quality of the underwater weld and meets engineering requirements.

Description

Technical Field

[0001] This disclosure belongs to the field of underwater welding technology, and particularly relates to an underwater local dry laser filler wire welding method and system. Background Technology

[0002] Underwater welding has been widely used in the manufacture and maintenance of offshore engineering structures, such as pipelines and nuclear power plants. In recent years, the rapid development of the marine industry has further promoted the application of underwater welding technology. Underwater welding is generally divided into dry welding, wet welding, and partially dry welding. Partially dry underwater welding mainly uses aeration and dewatering to provide a localized dry environment for underwater laser welding. Laser energy is used to melt the metal in the area to be welded. However, the weld pool in a water environment is prone to problems such as accelerated cooling, poor spread, poor fusion, and intergranular corrosion, which cannot meet the high requirements of engineering projects with demanding weld quality. Summary of the Invention

[0003] To address the deficiencies or shortcomings in existing technologies, this disclosure provides an underwater local dry laser wire-filled welding method and system, which can effectively improve the weld quality of underwater local dry welding and meet engineering application requirements.

[0004] To achieve the above objectives, the present disclosure adopts the following technical solution:

[0005] In a first aspect, embodiments of this disclosure provide an underwater local dry laser wire-filling welding system, including a drainage hood, an air supply device, a wire feeding device, a laser welding device, and a control system. The drainage hood is installed underwater and covers the underwater area to be welded. The control system is electrically connected to the air supply device, the wire feeding device, and the laser welding device, respectively.

[0006] It also includes an underwater drive unit, the drainage hood is fixed on the underwater drive unit, and the underwater drive unit is electrically connected to the control system.

[0007] Furthermore, the gas supply device is connected to the drain gas cover via a gas supply pipeline, and is used to introduce protective gas into the drain gas cover.

[0008] Furthermore, a wire feeding conduit is provided inside the drainage hood, and the wire feeding device is connected to the wire feeding conduit via a wire feeding pipeline.

[0009] Furthermore, the angle between the wire feeding guide and the base material is 30° to 60°.

[0010] Furthermore, the laser welding device includes a laser and an underwater welding device, with the laser connected to the underwater welding device via an optical fiber.

[0011] Furthermore, the underwater welding device is equipped with a laser welding head at its bottom end, which is used to adjust the angle between the center line of the laser beam and the base material.

[0012] Furthermore, the angle between the center line of the laser beam and the base material is 85° to 95°.

[0013] Furthermore, the laser welding device is also equipped with a water-cooling pipeline, which is used to cool the underwater welding device.

[0014] Secondly, embodiments of this disclosure provide an underwater localized dry laser wire filler welding method, utilizing the underwater localized dry laser wire filler welding system described above, including the following steps:

[0015] Cover the underwater welding area with a drainage gas cover, start the gas supply device to fill the drainage gas cover with protective gas, and wait for the water in the drainage gas cover to drain out to form a local dry area.

[0016] Start the wire feeding device and the laser welding device. The wire feeding device delivers the welding wire to the surface to be welded. The welding wire is irradiated by the laser beam and melts, forming a cladding layer on the surface to be welded.

[0017] The underwater drive device moves the drainage hood along the weld seam to perform cladding welding. After completing the cladding welding of the specified length, the laser welding device is turned off and the wire feeding is stopped. The underwater welding device is then moved back to the welding starting point.

[0018] Turn on the laser welding device and use the laser beam to irradiate the completed weld seam to remelt it.

[0019] Furthermore, during the remelting of the weld, the gas supply device continuously fills the drainage hood with gas to provide a localized dry environment.

[0020] Compared with the prior art, the beneficial effects of this disclosure are as follows:

[0021] This disclosure describes a process where, after underwater local dry welding is completed, a laser beam is used to remelt the weld, improving the surface microstructure of the weld, optimizing the weld forming performance, and solving problems such as accelerated weld cooling rate, poor spread, poor fusion, and intergranular corrosion in the underwater environment. This effectively improves the quality of the underwater weld and meets the requirements of engineering applications. Attached Figure Description

[0022] Figure 1 This is a connection diagram of the underwater local dry laser filler wire welding system device in Embodiment 1 of this disclosure;

[0023] Figure 2 This is a flowchart of the underwater local dry laser filler wire welding method in Embodiment 2 of this disclosure;

[0024] Among them, 1. Underwater surface to be welded; 2. Laser beam; 3. Welding wire; 4. Wire feeding conduit; 5. Shielding gas; 6. Drainage hood; 7. Underwater welding device; 8. Wire feeding pipeline; 9. Wire feeding device; 10. Gas supply pipeline; 11. Gas supply device; 12. Control system; 13. Laser; 14. Optical fiber; 15. Water cooling pipeline. Detailed Implementation

[0025] The present disclosure will be further described below with reference to the accompanying drawings and embodiments.

[0026] Terminology Explanation: The terms “installation,” “connection,” “linking,” and “fixing” in this disclosure should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to an internal connection between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.

[0027] Example 1

[0028] One typical implementation of this disclosure is as follows: Figure 1 As shown, an underwater local dry laser wire-filling welding system includes a drainage gas hood 6, a gas supply device 11, a wire feeding device 9, a laser welding device, and a control system 12. The drainage gas hood 6 is installed underwater and covers the underwater area to be welded. The control system 12 is electrically connected to the gas supply device 11, the wire feeding device 9, and the laser welding device. The control system 12 can adjust the laser power, wire feed speed, welding travel speed, and shielding gas flow rate according to the welding process requirements.

[0029] The gas supply device 11 is connected to the drainage gas cover 6 via the gas supply pipeline 10. It is used to introduce protective gas 5 into the drainage gas cover 6. The gas supply device 11 delivers gas from the gas supply pipeline 10 to the inside of the drainage gas cover 6 to fill and drain the gas, forming a local dry area. After the drainage is completed, the protective gas 5 fills the inside of the drainage gas cover 6, forming an effective gas protection for the surface 1 to be welded, effectively reducing the influence of hydrogen atoms in the water on the weld, and preventing oxidation during the welding process.

[0030] Furthermore, the protective gas 5 can be pure argon or pure nitrogen, or a mixture of argon and nitrogen.

[0031] The drainage hood 6 is equipped with a wire feeding guide 4, and the angle between the wire feeding guide 4 and the base material is 30° to 60°. The wire feeding device 9 is connected to the wire feeding guide 4 through the wire feeding pipeline 8, and is used to convey the welding wire 3 to the underwater surface to be welded 1.

[0032] Furthermore, the wire feeding device 9 can be an underwater wire feeder, or it can be located on the water with a wire feeding pipeline and an auxiliary wire feeding motor configured underwater for long-distance wire feeding.

[0033] The laser welding device is used to emit a laser beam towards the surface 1 to be welded, melting the welding wire 3 to form a cladding layer. The laser welding device includes a laser 13 and an underwater welding device 7. The laser 13 is connected to the underwater welding device 7 via an optical fiber 14. The underwater welding device 7 is fixed on a drainage hood 6, with its bottom end located inside the drainage hood 6. A laser welding head is provided at the bottom end of the underwater welding device 7, and the laser welding head is used to adjust the angle between the center line of the laser beam 2 and the base material.

[0034] Furthermore, the angle between the center line of the laser beam 2 and the base material is 85° to 95°.

[0035] The laser welding device is also equipped with a water cooling pipeline 15, which is used to cool the underwater welding device 7. The underwater welding device 7 irradiates the laser beam 2 generated by the laser 13 onto the surface 1 to be welded. The welding wire 3 located on the surface 1 to be welded is irradiated by the laser beam 2 and melts to form a cladding layer.

[0036] The underwater local dry laser filler wire welding system also includes an underwater drive device, which is electrically connected to the control system 12. The underwater drive device can drive the underwater welding device 7 and the drainage hood 6 to move along the weld seam.

[0037] Specifically, the underwater drive device includes an X-axis displacement mechanism, a Y-axis displacement mechanism, and a Z-axis displacement mechanism. All three displacement mechanisms are driven by servo motors that drive lead screws and nuts, and are equipped with good waterproofing measures. The servo motors are connected to the control system, thereby using the control system to control the movement of the three-axis displacement mechanisms. The drainage hood and the underwater welding device are both fixed on the Z-axis displacement mechanism to drive the movement of the drainage hood and the underwater welding device.

[0038] The Z-axis displacement mechanism is also equipped with a laser distance sensor and a camera. Both the laser distance sensor and the camera are electrically connected to the control system. The laser distance sensor is used to detect the distance between itself and the underwater surface to be welded, and the camera is used to observe the underwater welding process.

[0039] Example 2

[0040] This embodiment provides an underwater localized dry laser wire welding method, utilizing an underwater localized dry laser welding system as described in Embodiment 1, such as... Figure 2 As shown, it includes the following steps:

[0041] Cover the underwater welding area with a drainage gas cover, start the gas supply device to fill the drainage gas cover with protective gas, and wait for the water in the drainage gas cover to drain out to form a local dry area; after the drainage is completed, the protective gas fills the inside of the drainage gas cover, forming an effective gas protection for the surface to be welded.

[0042] Start the wire feeding device and the laser welding device. The wire feeding device feeds the welding wire to the surface to be welded. The welding wire is irradiated by the laser beam and melts, forming a cladding layer on the surface to be welded.

[0043] The underwater drive device moves the drainage hood along the weld seam to perform cladding welding. After completing the cladding welding of the specified length, the laser welding device is turned off and the wire feeding is stopped. The underwater welding device is then moved back to the welding starting point.

[0044] The laser welding device is turned on, and the completed weld is irradiated with laser light to remelt the weld, thereby improving the bonding between the weld and the base material and optimizing the weld performance. During the remelting process, the gas supply device continuously fills and drains the drainage hood to provide a local dry environment.

[0045] When multiple layers or multiple passes of weld are required, a laser beam is irradiated between each layer or pass of weld to perform remelting, thereby improving the bonding between the multiple welds and the base material.

[0046] The above description is merely a preferred embodiment of this disclosure and is not intended to limit this disclosure. Various modifications and variations can be made to this disclosure by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the scope of protection of this disclosure.

Claims

1. An underwater localized dry laser filler wire welding system, characterized in that, It includes a drainage hood, an air supply device, a wire feeding device, a laser welding device, and a control system. The drainage hood is installed underwater and covers the underwater area to be welded. The control system is electrically connected to the air supply device, the wire feeding device, and the laser welding device. Turn on the laser welding device and use the laser beam to irradiate the completed weld to remelt the weld, thereby improving the bonding between the weld and the base material and optimizing the weld performance. During the remelting process, the gas supply device continuously fills and drains the drainage hood to provide a local dry environment. When multiple layers or multiple passes of weld are required, a laser beam is irradiated between each layer or pass of weld to perform remelting, thereby improving the bonding between the multiple welds or multiple passes of weld and the base material. It also includes an underwater drive device, on which the drainage hood is fixed. The underwater drive device is electrically connected to the control system. The underwater drive device drives the drainage hood to move along the weld seam and performs cladding welding on the weld seam. After completing the cladding welding of the specified length, the laser welding device is turned off and the wire feeding is stopped. The underwater welding device is then moved back to the welding starting point.

2. The underwater local dry laser filler wire welding system as described in claim 1, characterized in that, The gas supply device is connected to the drain gas cover via a gas supply pipeline and is used to introduce protective gas into the drain gas cover.

3. The underwater local dry laser filler wire welding system as described in claim 1, characterized in that, The drain hood is equipped with a wire feeding conduit, and the wire feeding device is connected to the wire feeding conduit via a wire feeding pipeline.

4. The underwater local dry laser filler wire welding system as described in claim 3, characterized in that, The angle between the wire feeding guide and the base material is 30°~60°.

5. The underwater local dry laser filler wire welding system as described in claim 1, characterized in that, The laser welding device includes a laser and an underwater welding device, with the laser connected to the underwater welding device via an optical fiber.

6. The underwater local dry laser filler wire welding system as described in claim 5, characterized in that, The underwater welding device is equipped with a laser welding head at its bottom end, which is used to adjust the angle between the center line of the laser beam and the base material.

7. The underwater local dry laser filler wire welding system as described in claim 6, characterized in that, The angle between the center line of the laser beam and the base material is 85°~95°.

8. The underwater local dry laser filler wire welding system as described in claim 5, characterized in that, The laser welding device is also equipped with a water-cooling pipeline, which is used to cool the underwater welding device.

9. An underwater localized dry laser filler wire welding method, utilizing an underwater localized dry laser filler wire welding system as described in any one of claims 1-8, characterized in that, Includes the following steps: Cover the underwater welding area with a drainage gas cover, start the gas supply device to fill the drainage gas cover with protective gas, and wait for the water in the drainage gas cover to drain out to form a local dry area. Start the wire feeding device and the laser welding device. The wire feeding device delivers the welding wire to the surface to be welded. The welding wire is irradiated by the laser beam and melts, forming a cladding layer on the surface to be welded. The underwater drive device moves the drainage hood along the weld seam to perform cladding welding. After completing the cladding welding of the specified length, the laser welding device is turned off and the wire feeding is stopped. The underwater welding device is then moved back to the welding starting point. Turn on the laser welding device and use the laser beam to irradiate the completed weld seam to remelt it.

10. The underwater local dry laser filler wire welding method as described in claim 9, characterized in that, During the remelting of the weld, the gas supply device continuously fills the drainage hood with air to provide a localized dry environment.

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