An underwater welding seam detection and laser repair integrated device and method thereof

Abstract

This invention discloses an integrated device and method for underwater weld inspection and laser repair, relating to the field of underwater welding processing technology. The device includes an ultrasonic inspection system, a laser repair system, a drainage system, an inflation system, and a working sealed chamber. The device uses a flexible coupling lip to tightly adhere to the weld surface and maintain the stability of the sealed dry chamber during movement. A miniature suction pump discharges seawater while simultaneously filling the chamber with protective gas to maintain pressure and dryness, providing a dry, oxygen-free environment for laser cladding. The ultrasonic inspection system employs an elastic sliding device to effectively conform to the weld. Integrated intelligent control and underwater visual monitoring enable fully automated operation. A dual-independent, time-sharing collaborative structure allows for physical separation of the inspection and repair mechanisms. This invention effectively improves the accuracy and efficiency of underwater weld inspection and repair, reduces operational risks, and is suitable for weld maintenance of underwater steel structures such as subsea pipelines and offshore platforms, showing broad application prospects.

Description

Technical Field

[0001] This invention relates to the field of underwater welding processing technology, specifically to an integrated device and method for underwater weld inspection and laser repair. Background Technology

[0002] Underwater steel structures are subjected to complex marine environments characterized by high salinity, high pressure, and alternating loads. Their welds are prone to various defects such as cracks, porosity, incomplete penetration, and corrosion pits, seriously threatening structural safety and service life. Traditional maintenance methods primarily rely on manual diving operations. This is not only high-risk and inefficient, but also limited by the diver's subjective judgment and operating conditions, making it difficult to guarantee inspection accuracy and repair quality.

[0003] Existing underwater operation equipment is mostly designed for a single function, such as separating inspection equipment from repair equipment. This "separate equipment, separate stages" operation mode is prone to deviations in defect location and repair position, making it impossible to achieve in-situ re-inspection and closed-loop repair, resulting in low operation efficiency and reliability, and insufficient adaptability of weld morphology.

[0004] Furthermore, most equipment lacks the ability to adapt to complex weld morphologies. Conventional rigid contact or sealing mechanisms are difficult to achieve stable, follow-up contact underwater, which can easily lead to poor coupling or partial detachment of the ultrasonic testing probe, severely affecting the stability and accuracy of the detection signal.

[0005] Even with preliminary measures such as localized drainage, moisture and air may still remain in the work chamber during the repair process. Under the high temperatures generated during subsequent welding repair, these residues will decompose and produce harmful gases, which can easily lead to new defects such as porosity and inclusions in the cladding layer, making it difficult to control the repair quality. Summary of the Invention

[0006] The purpose of this invention is to provide an integrated device and method for underwater weld inspection and laser repair, so as to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: an integrated device for underwater weld inspection and laser repair, comprising a working sealed cavity, an upper sealing box and a lower sealing box respectively provided above and below the working sealed cavity, an upper robotic arm provided on the upper sealing box, and a lower robotic arm provided on the lower sealing box, wherein the upper robotic arm and the lower robotic arm are capable of gripping the side wall of the underwater weld structure. An ultrasonic testing system is installed inside the working sealed cavity. The ultrasonic testing system includes an underwater ultra-high-definition camera and an ultrasonic testing probe, which are used to inspect the underwater weld structure through vision and ultrasound. A laser repair system is installed above the ultrasonic testing system, and the laser repair system repairs the weld seam through laser cladding. The upper sealing box is equipped with an inflation system, and the lower sealing box is equipped with a drainage system. The inflation system discharges water from the drainage system by inflating air into the working sealing cavity.

[0008] Preferably, the ultrasonic detection system further includes a mounting plate, a lighting lamp, and a pressure sensor. The lighting lamp, underwater ultra-high-definition camera, ultrasonic detection probe, and pressure sensor are all fixed on the mounting plate from top to bottom. The mounting plate is connected to a lead screw drive shaft. The root of the lead screw drive shaft is connected to a sliding block. The sliding block is slidably connected to a vertical sliding seat. The vertical sliding seat is installed in the working sealed cavity. The lead screw drive shaft is also provided with a lead screw nut and a spring. Symmetrical guide optical shafts are provided on the upper and lower sides of the lead screw drive shaft. The guide optical shafts pass through a sleeve, which is installed on the sliding seat. The limiting block is fixed to the end of the guide optical shaft.

[0009] Preferably, the laser repair system further includes a laser head and a powder spraying pipe. The laser head is provided with a protective cover on its outer side. The laser head is fixed on a horizontal telescopic rod. The other end of the horizontal telescopic rod is connected to a vertical telescopic rod. The vertical telescopic rod is fixed on a slide rail. The powder spraying pipe is connected between the laser head and the powder spraying box. The side of the powder spraying box is provided with a laser, and both are fixed inside the upper sealed box.

[0010] Preferably, the front end of the working sealing cavity is connected to a flexible coupling lip, which flexibly fits against the sidewall of the underwater weld structure.

[0011] Preferably, the upper and lower robotic arms are telescopic and extendable, and both are equipped with suction cups at their ends.

[0012] Preferably, the drainage system includes a drainage pipe, a one-way valve, and a micro suction pump. One end of the drainage pipe is connected to the working sealing chamber, and the other end is connected to the micro suction pump. The micro suction pump is fixed in the lower sealing box, and a one-way valve is connected below its drain outlet.

[0013] Preferably, the inflation system includes a protective gas sealed container, a connecting pipe, and an inflation pump. The protective gas sealed container and the inflation pump are fixed in the upper sealed box and are connected to each other for air supply through the connecting pipe, which is equipped with an electric valve.

[0014] Preferably, a motor is installed inside the lower sealing box, and the motor is fixed inside the lower sealing box by a connecting plate. The motor is connected to the lead screw drive shaft for transmission.

[0015] Preferably, a central control panel is provided inside the lower sealed box.

[0016] A method for integrating underwater weld inspection and laser repair includes the following steps: Step S1: Positioning, sealing, and dry cavity formation The device is moved to the weld seam, and the flexible coupling lip fits against the sidewall of the underwater weld structure. High-purity protective gas is then introduced to drain the water, creating a dry, oxygen-free, sealed working space. Step S2: Ultrasonic Testing and Data Upload The ultrasonic testing system scans along the weld seam, and combined with an underwater ultra-high-definition camera, visually assists in locating defects and measuring their dimensions. The data is then uploaded to the central control station in real time. Step S3: Laser Repair and Positioning After a defect is detected, the ultrasonic detection system is retracted, and the central control unit drives the laser repair system to precisely align the laser head with the defect area based on the defect information. Step S4: Laser Cladding Repair The laser is activated, powder is fed synchronously, and laser cladding repair is performed on the defects under the protection of protective gas. Step S5: Re-inspection and Cyclic Operation The repaired area was subjected to ultrasonic testing again to confirm that the quality was up to standard. The dry cavity environment was continuously maintained during the movement of the device, and the above steps were repeated until all welds were treated.

[0017] Compared with the prior art, the beneficial effects of the present invention are: This invention uses an inflation system to fill the working sealed cavity with protective gas, which helps to drain water from the cavity, maintains a dry working environment, and creates a protective atmosphere to provide gas protection for the repair process. Simultaneously, during welding, protective gas is continuously introduced from above and discharged from below, effectively removing water vapor and waste gas caused by the high temperature of laser repair, preventing these substances from affecting the repair site. Finally, the continuously introduced protective gas removes the high temperature of the laser repair, preventing the working sealed cavity from detaching from the underwater weld structure due to increased gas pressure caused by the high temperature. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the ultrasonic testing system of the present invention; Figure 3 This is a schematic diagram of the laser repair system of the present invention; Figure 4 This is a flowchart of the implementation method of the present invention.

[0019] In the diagram: 1-Underwater weld structure; 2-Upper robotic arm; 3-Suction cup; 4-Flexible coupling lip; 5-Laser repair system; 501-Protective cover; 502-Laser head; 503-Powder spraying pipe; 504-Horizontal telescopic rod; 505-Vertical telescopic rod; 506-Slide rail; 507-Laser; 508-Powder spraying tank; 6-Ultrasonic testing system; 601-Mounting plate; 602-Lighting lamp; 603-Underwater ultra-high-definition camera; 604-Ultrasonic testing probe; 605-Pressure sensor; 606-Spring; 607-Lead screw nut; 608-Lead screw drive shaft; 609-Sleeve; 610-Sliding seat; 611-Guide optical axis; 612-Vertical sliding seat; 613-Sliding block; 614-Limit block; 7-Lower robotic arm; 8-Drainage system; 801-Drainage pipe; 802-Check valve; 803-Miniature suction pump; 9-Lower sealing box; 10-Central control panel; 11-Motor; 12-Connecting plate; 13-Working sealing cavity; 14-Upper sealing box; 15-Inflation system; 151-Protective gas sealing tank; 152-Connecting pipe; 153-Inflation pump. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0021] In existing technologies, the detection and repair processes are fragmented. Most current underwater equipment is single-function, with detection and repair performed separately by different devices and in different stages. This leads to errors in defect location and repair position, making in-situ re-inspection and closed-loop repair impossible. Operational efficiency and reliability are low, and the weld morphology self-adaptation capability is insufficient. Conventional rigid mechanisms cannot achieve dynamic fit, easily causing ultrasonic probe coupling failure. Therefore, there is an urgent need for an integrated underwater weld detection and laser repair device and method that integrates non-destructive testing, laser cladding repair, dynamic dry cavity environment protection, and adaptive contouring into a unified underwater operation. Please see Figure 1The present invention provides a technical solution: an integrated underwater weld inspection and laser repair device, comprising an underwater weld structure 1, including an ultrasonic inspection system 6, a laser repair system 5, a drainage system 8, an air inflation system 15, a working sealed cavity 13, a motor 11, and a central control panel 10. An upper sealed box 14 and a lower sealed box 9 are respectively fixed above and below the working sealed cavity 13 by bolt connection. The bases of the upper robotic arm 2 and the lower robotic arm 7 are fixed on the upper sealed box 14 and the lower sealed box 9 by bolt connection. A suction cup 3 is installed at the end of the upper robotic arm 2 and the lower robotic arm 7.

[0022] The drainage system 8 includes a drainage pipe 801, a one-way valve 802, and a micro suction pump 803. The drain outlet of the working sealed chamber 13 is connected to the inlet of the micro suction pump 803 by the drainage pipe 801. The micro suction pump 803 is fixed in the lower sealed box 9 and the one-way valve 802 is connected below the drain outlet. The inflation system 15 includes a protective gas sealed tank 151, a connecting pipe 152, and an inflation pump 153. The protective gas sealed tank 151 and the inflation pump 153 are fixed in the upper sealed box 14 and are connected to each other for ventilation through the connecting pipe 152. An electric valve is installed on the pipe. The motor 11 is fixed above the lower sealed box 9 through the connecting plate 12. The central control panel 10 is connected below the lower sealed box 9.

[0023] The gas filling system 15 introduces protective gas into the working sealing cavity 13. This serves two purposes: firstly, it helps to drain water from the working sealing cavity 13, maintaining a dry working environment; secondly, it creates a protective atmosphere to provide gas protection for the repair; and thirdly, it continuously introduces protective gas from above and discharges it from below during welding, effectively removing water vapor and exhaust gas caused by the high temperature generated during laser repair, preventing these water vapor and exhaust gases from affecting the repair site. Finally, the continuously introduced protective gas removes the high temperature of the laser repair, preventing the high temperature from causing an increase in gas pressure and causing the working sealing cavity 13 to detach from the underwater weld structure 1.

[0024] The front end of the working sealing cavity 13 is connected to a flexible coupling lip 4 made of rubber, such as... Figure 1 As shown, the flexible coupling lip 4 flexibly fits the surface of the underwater weld structure 1 under test. Together with the adsorption of the upper robotic arm 2, the lower robotic arm 7, and the suction cup 3 on them, a local sealing area is formed to prevent external water from entering the working sealing cavity 13 and to ensure a dry testing environment. At the same time, after the inflation system 15 inflates the working sealing cavity 13, the pressure generated by the inflation is kept below the water pressure. The water pressure causes the working sealing cavity 13 to be pressed against the side wall of the underwater weld structure 1.

[0025] like Figure 2As shown, the ultrasonic testing system 6 includes a mounting plate 601, a lighting lamp 602, an underwater ultra-high-definition camera 603, an ultrasonic testing probe 604, a pressure sensor 605, a spring 606, a lead screw nut 607, a lead screw drive shaft 608, a sleeve 609, a sliding seat 610, a guide optical shaft 611, a vertical sliding seat 612, a sliding block 613, and a limiting block 614. The vertical sliding seat 612 is connected to a transverse sliding seat built into the sealed chamber. The sliding block 613 is embedded in the vertical sliding seat 612 and slides. The lead screw drive shaft 608 is connected to the sliding block 613. The lead screw nut 607 and the spring 606 are sleeved on the lead screw drive shaft 608. The guide optical shaft 611 is parallel to the lead screw drive shaft. The upper and lower sides of shaft 608 are arranged, passing through sleeve 609 and connected to the mounting plate. Limiting block 614 is fixed to the end of guide optical shaft 611. Lighting lamp 602, underwater ultra-high-definition camera 603, ultrasonic detection probe 604, and pressure sensor 605 are all fixed on mounting plate 601 from top to bottom. Motor 11 drives lead screw transmission shaft 608 to make ultrasonic detection probe 604 stably coupled with weld surface. Lead screw nut 607 moves compression spring 606 to maintain constant contact pressure through pressure sensor 605. Lighting lamp 602 and underwater ultra-high-definition camera 603 assist in detecting surface quality of weld, complete weld defect location and size detection, and transmit data to central control console 10.

[0026] like Figure 3 As shown, the laser repair system 5 includes a protective cover 501, a laser head 502, a powder spraying pipe 503, a horizontal telescopic rod 504, a vertical telescopic rod 505, a slide rail 506, a laser 507, and a powder spraying tank 508. The protective cover 501 is installed on the upper part of the laser head 502. The laser head 502 is fixed on the horizontal telescopic rod 504. The other end of the horizontal telescopic rod 504 is connected to the vertical telescopic rod 505. The vertical telescopic rod 505 is fixed on the slide rail 506. The laser 507 and the powder spraying tank 508 are fixed in the upper sealed box 14. The powder spraying tank 508 is connected to the laser head 502 through the powder spraying pipe 503. According to the defect information, the central control console 10 controls the horizontal telescopic rod 504 and the vertical telescopic rod 505 of the laser repair system 5 to adjust the position of the laser head 502 and align it with the defect area. The laser 507 is started, and the powder spraying device 508 simultaneously delivers powder. Under the protection of the protective gas, the weld defect is repaired by laser cladding, realizing material filling and defect elimination. After the repair is completed, the laser repair system 5 is reset.

[0027] The laser 507 is a carbon dioxide laser with a wavelength of 10.6 μm and an output power that is continuously adjustable from 800 W to 3000 W; the powder spraying can 508 uses nickel-based alloy powder with a particle size of 50 μm to 120 μm and a powder feeding rate of 6 g / min to 28 g / min; the ultrasonic detection probe 604 includes a 2.5 MHz to 5 MHz straight probe and a K2 to K3 angled probe, which are maintained at a coupling pressure of 0.1 MPa to 0.3 MPa by a spring 606.

[0028] A method for integrating underwater weld inspection and laser repair includes the following steps: Step S1: Positioning, draining, and inflating. The entire device is moved to the underwater weld position by the power unit, so that the flexible coupling lip 4 fits against the weld surface. At the same time, the two robotic arms are firmly attached to the surface to be inspected by the suction cups 3 at the ends to prevent lateral displacement that could cause the flexible coupling lip 4 to partially detach. The central control panel 10 controls the micro suction pump 151 to start, and drains the water from the working sealing chamber 13 through the drainage pipe 152. The one-way valve 802 prevents backflow, forming a dry working space. At the same time, the air pump 151 starts, filling the working sealing chamber 13 with high-purity protective gas to maintain the pressure inside the sealing chamber and discharge residual air, forming an oxygen-free protective atmosphere to prepare for laser repair. Step S2: Ultrasonic inspection of the weld. The ultrasonic inspection system 6 moves to detect via the slide rail 506. The motor 11 drives the lead screw drive shaft 608 to stably couple the ultrasonic inspection probe 604 with the weld surface. The lead screw nut 607 moves the compression spring 606 to maintain a constant contact pressure through the pressure sensor 605. The lighting lamp 602 and the underwater ultra-high-definition camera 603 assist in detecting the surface quality of the weld, completing the location of weld defects and size detection, and transmitting the data to the central control console 10. Step S3: The laser repair system is in place. When a defect is detected, the ultrasonic detection system 6 moves into the working sealed cavity 13, the lead screw drive shaft 608 retracts, and the central control console 10 controls the horizontal telescopic rod 504 and the vertical telescopic rod 505 of the laser repair system 5 to adjust the position of the laser head 502 and align it with the defect area according to the defect information. Step S4: Laser repair of weld defects. Laser 507 is activated, and powder spraying device 508 simultaneously feeds powder. Under the protection of shielding gas, laser cladding repair is performed on the weld defects to achieve material filling and defect elimination. After repair, the laser repair system 5 is reset. Step S5: The repaired weld area is inspected again. The ultrasonic testing system 6 inspects the repaired area again to confirm that the defects have been eliminated and the cladding layer is of qualified quality. The underwater weld is then inspected again. The device maintains a dry chamber during movement. The micro suction pump 803 continuously pumps out the small amount of seawater that has seeped in, and the air pump 153 simultaneously fills in dry inert gas. The above steps are repeated until the underwater weld inspection and repair are completed.

[0029] As is known from common technical knowledge, this invention can be implemented through other embodiments that do not depart from its spirit or essential characteristics. Therefore, the disclosed embodiments described above are merely illustrative and not exhaustive. All modifications within the scope of this invention or its equivalents are included in this invention.

Claims

1. An integrated device for underwater weld inspection and laser repair, characterized in that: The structure includes a working sealing cavity (13), with an upper sealing box (14) and a lower sealing box (9) respectively located above and below the working sealing cavity (13). An upper robotic arm (2) is provided on the upper sealing box (14), and a lower robotic arm (7) is provided on the lower sealing box (9). The upper robotic arm (2) and the lower robotic arm (7) can be attached to the side wall of the underwater weld structure (1). The working sealed cavity (13) is equipped with an ultrasonic detection system (6), which includes an underwater ultra-high-definition camera (603) and an ultrasonic detection probe (604) for detecting the underwater weld structure (1) through vision and ultrasound. A laser repair system (5) is provided above the ultrasonic testing system (6), and the laser repair system (5) repairs the weld seam by laser cladding; The upper sealing box (14) is equipped with an inflation system (15), and the lower sealing box (9) is equipped with a drainage system (8). The inflation system (15) discharges water from the drainage system (8) by inflating air into the working sealing cavity (13).

2. The integrated underwater weld inspection and laser repair device according to claim 1, characterized in that: The ultrasonic detection system (6) further includes a mounting plate (601), a lighting lamp (602), and a pressure sensor (605). The lighting lamp (602), the underwater ultra-high-definition camera (603), the ultrasonic detection probe (604), and the pressure sensor (605) are all fixed on the mounting plate (601) from top to bottom. The mounting plate (601) is connected to the lead screw drive shaft (608). The root of the lead screw drive shaft (608) is connected to the sliding block (613). The vertical sliding seat (612) is slidably connected to the vertical sliding seat (612), which is installed in the working sealing cavity (13). The screw drive shaft (608) is also provided with a screw nut (607) and a spring (606). Symmetrical guide shafts (611) are provided on the upper and lower sides of the screw drive shaft (608). The guide shafts (611) pass through the sleeve (609), which is installed on the sliding seat (610). The limiting block (614) is fixed at the end of the guide shaft (611).

3. The integrated underwater weld inspection and laser repair device according to claim 1, characterized in that: The laser repair system (5) also includes a laser head (502) and a powder spraying pipe (503). The laser head (502) is provided with a protective cover (501) on its outer side. The laser head (502) is fixed on a horizontal telescopic rod (504). The other end of the horizontal telescopic rod (504) is connected to a vertical telescopic rod (505). The vertical telescopic rod (505) is fixed on a slide rail (506). The powder spraying pipe (503) is connected between the laser head (502) and the powder spraying box (508). The side of the powder spraying box (508) is provided with a laser (507), and both are fixed inside the upper sealed box (14).

4. The integrated underwater weld inspection and laser repair device according to claim 1, characterized in that: The front end of the working sealing cavity (13) is connected to a flexible coupling lip (4), which flexibly fits against the side wall of the underwater weld structure (1).

5. The integrated underwater weld inspection and laser repair device according to claim 1, characterized in that: The upper robotic arm (2) and the lower robotic arm (7) are capable of extending and retracting forward and backward, and both are equipped with suction cups (3) at their ends.

6. The integrated underwater weld inspection and laser repair device according to claim 1, characterized in that: The drainage system (8) includes a drainage pipe (801), a one-way valve (802), and a micro suction pump (803). One end of the drainage pipe (801) is connected to the working sealing chamber (13), and the other end is connected to the micro suction pump (803). The micro suction pump (803) is fixed in the lower sealing box (9), and a one-way valve (802) is connected below its drain outlet.

7. The integrated underwater weld inspection and laser repair device according to claim 2, characterized in that: The inflation system (15) includes a protective gas sealed container (151), a connecting pipe (152) and an inflation pump (153). The protective gas sealed container (151) and the inflation pump (153) are fixed in the upper sealed box (14) and are connected to each other for ventilation through the connecting pipe (152). An electric valve is installed on the connecting pipe (152).

8. The integrated underwater weld inspection and laser repair device according to claim 1, characterized in that: The lower sealing box (9) is equipped with a motor (11), which is fixed in the lower sealing box (9) by a connecting plate (12). The motor (11) is connected to the lead screw drive shaft (608).

9. The integrated underwater weld inspection and laser repair device according to claim 1, characterized in that: The lower sealing box (9) is equipped with a central control panel (10).

10. A method for underwater weld inspection and laser repair using the apparatus described in claims 1-9, characterized in that: Includes the following steps: Step S1: Positioning, sealing, and dry cavity formation The device is moved to the weld seam, and the flexible coupling lip (4) fits against the sidewall of the underwater weld seam structure (1). High-purity protective gas is introduced to drain the water, forming a dry and oxygen-free sealed working space; Step S2: Ultrasonic Testing and Data Upload The ultrasonic testing system (6) scans along the weld seam, and combines the underwater ultra-high-definition camera (603) to visually assist in locating defects and measuring their dimensions. The data is uploaded to the central control console (10) in real time. Step S3: Laser Repair and Positioning After a defect is detected, the ultrasonic detection system (6) is retracted, and the central control panel (10) drives the laser repair system (5) to precisely align the laser head (502) with the defect area based on the defect information. Step S4: Laser Cladding Repair Start the laser (507), feed powder synchronously, and perform laser cladding repair on the defects under the protection of protective gas; Step S5: Re-inspection and Cyclic Operation The repaired area was subjected to ultrasonic testing again to confirm that the quality was up to standard. The dry cavity environment was continuously maintained during the movement of the device, and the above steps were repeated until all welds were treated.

Images