A full-automatic flaw detector for welding defects of seamless stainless steel pipe

Abstract

The application discloses a kind of seamless stainless steel pipe weld defect full-automatic flaw detection device, it is related to weld flaw detection technical field, specifically including workbench, the both ends of the workbench are provided with steel pipe rack, steel pipe weld is located between two steel pipe racks, and detection mechanism is provided between two steel pipe racks, the detection mechanism includes two sealable sealing half circles, two sealing half circles are closed and are jointly enclosed into sealing cavity with steel pipe outer wall, and the end of sealing half circle is movably sleeved with inner ring, sealing half circle is contacted with steel pipe by inner ring, vacuum extraction structure is provided on the workbench.The application is wrapped to the weld, to construct sealing cavity, and air in sealing cavity is extracted using vacuum pump, to avoid air mixing even dissolving in couplant to form micro-bubble in the process of flaw detection and the process of couplant smearing, guarantee the acoustic energy transmission efficiency of coupling layer, improve the sensitivity of detection, reduce the probability of missed diagnosis.

Description

Technical Field

[0001] This invention relates to the field of weld flaw detection technology, specifically to a fully automatic flaw detection device for weld defects in seamless stainless steel pipes. Background Technology

[0002] Seamless stainless steel pipes possess characteristics such as corrosion resistance, high strength, and excellent sealing performance, making them widely used in harsh working conditions such as chemical, energy, and fluid transportation. In actual engineering assembly, adjacent seamless stainless steel pipes can be butt-connected by welding, with the weld being a critical load-bearing component. Due to welding processes and environmental factors, latent defects such as cracks, lack of fusion, and porosity can easily develop inside the weld. If these defects are not detected in time, the pipeline is highly susceptible to leakage, breakage, and other safety accidents during pressure-bearing service. Therefore, non-destructive testing of the weld after welding is a necessary procedure to ensure the safety of pipeline operation.

[0003] In current industrial production, ultrasonic testing has become the most commonly used non-destructive testing method for stainless steel pipe welds due to its advantages of being radiation-free, having strong penetration, and low testing cost. However, the effective transmission of ultrasonic waves is highly dependent on the coupling medium between the probe and the pipe. In actual production, weld surfaces often have residual weld beads, weld spatter, and rust, resulting in a rough and uneven contact surface. This rough interface causes severe scattering and energy attenuation of ultrasonic waves, leading to drastic fluctuations in echo signal amplitude and significant defect noise interference, greatly increasing the risk of misdiagnosis and missed detection. To address this problem, existing technologies often integrate grinding mechanisms into the flaw detection device to pre-treat the weld surface, but the coupling stability during the testing process is still difficult to guarantee. Especially during the application of the coupling agent and the testing process, air can easily mix into or even dissolve in the coupling agent, forming microbubbles due to environmental and air disturbances. These bubbles not only change the acoustic homogeneity of the coupling agent but also cause additional scattering and attenuation of ultrasonic waves, severely weakening the acoustic energy transmission efficiency of the coupling layer, thus affecting the detection sensitivity and easily leading to missed diagnoses. Furthermore, when the probe comes into contact with and is squeezed against the steel pipe, the coupling agent between the probe and the steel pipe is prone to flow under the action of gravity, causing dynamic fluctuations in the thickness of the coupling layer. This severely damages the stability and uniformity of the acoustic contact, easily leading to unstable coupling state and further reducing the quality of weld flaw detection.

[0004] Based on this, this application proposes a fully automatic flaw detection device for weld defects in seamless stainless steel pipes. Summary of the Invention

[0005] This invention provides a fully automatic flaw detection device for weld defects in seamless stainless steel pipes, which solves the problems mentioned in the background art, such as the influence of environmental and air disturbances, the easy mixing and even dissolution of air in the coupling agent to form microbubbles, which easily weakens the acoustic energy transmission efficiency of the coupling layer, affects the detection sensitivity, and easily leads to missed diagnoses; and the thickness of the coupling agent between the probe and the steel pipe is prone to dynamic fluctuations due to gravity, resulting in unstable coupling between the two, which in turn affects the detection quality.

[0006] This invention provides the following technical solution: a fully automatic flaw detection device for weld defects in seamless stainless steel pipes, comprising a workbench, with steel pipe placement racks at both ends of the workbench, the steel pipe weld located between the two steel pipe placement racks, and a detection mechanism between the two steel pipe placement racks. The detection mechanism includes two openable and closable sealing semicircles, which, when closed, together with the outer wall of the steel pipe, form a sealed cavity. An inner ring is movably fitted at the end of each sealing semicircle, and the sealing semicircle contacts the steel pipe through the inner ring. A vacuum structure is provided on the workbench, with the air inlet of the vacuum structure extending into the sealed cavity. Coupling agent application and recovery components are provided on both sides of one end of the sealed cavity. A first ultrasonic detection probe is provided on one side of one coupling agent application and recovery component, and a second ultrasonic detection probe is provided on one side of the other coupling agent application and recovery component. The first and second ultrasonic detection probes are arranged opposite to each other, and a spray rinsing component is provided inside the sealed cavity. The coupling agent application and recovery assembly includes a coupling agent application head and a coupling agent recovery head that are movably connected to the sealed cavity. The coupling agent recovery head is connected to the sealed cavity through a second linear moving structure. A coupling agent storage cylinder and a vacuum cleaner are disposed outside the sealed cavity. The liquid outlet of the coupling agent storage cylinder is connected to the liquid inlet of the coupling agent application head through a connecting pipe. The coupling agent recovery head is connected to the fluid inlet of the vacuum cleaner.

[0007] Preferably, the outer side of the steel pipe placement rack is provided with a steel pipe fixing and rotating structure, which includes two outer clamping plates. The steel pipe is located between the two outer clamping plates. The two outer clamping plates are connected to the worktable through a first linear moving structure. Inner clamping rings are movably arranged on the inner sidewalls of the two outer clamping plates. A first driving structure is provided on the outer side of one of the outer clamping plates. When the two steel pipe fixing and rotating structures clamp and fix the steel pipe, the two inner clamping rings form an active rotating ring, which is driven to rotate by the first driving structure.

[0008] Preferably, the vacuuming structure includes a vacuum pump and a vacuum tube connected to the air inlet of the vacuum pump. The air inlet of the vacuum tube is connected to a sealed semicircle, and a one-way valve is provided at the air inlet of the vacuum tube.

[0009] Preferably, the outer ring of the coupling agent storage cylinder is movably fitted with a support sleeve, which is connected to the outer surface of the sealing semicircle; the liquid inlet end of the coupling agent storage cylinder is provided with a liquid replenishment check valve, and the inner cavity of the coupling agent storage cylinder is movably connected with a squeezing plate, which is connected to the coupling agent storage cylinder through a third linear moving structure.

[0010] Preferably, a waste liquid collection box is provided on the workbench, the waste liquid collection box is located below the sealed cavity, and a drain pipe is provided on one side of the bottom end of the inner cavity of the waste liquid collection box.

[0011] Preferably, the inner walls of both the coupling agent application head and the coupling agent recovery head are arc-shaped surfaces with the same inner diameter. When the two coupling agent application heads are closed, an annular gap is formed between them and the steel pipe, and the thickness of the annular gap is the same as the thickness of the applied coupling agent.

[0012] Preferably, a shielding plate is provided on the side of the sealing semicircle away from the first ultrasonic testing probe. The shielding plate is connected to the sealing semicircle by a straight rod. The inner diameter of the shielding plate is larger than the outer diameter of the steel pipe. The outer wall of the shielding plate is adapted to the arc-shaped surface. The thickness of the shielding plate is less than the thickness of the coupling agent coating.

[0013] Preferably, the side of the coupling agent application head away from the coupling agent recovery head is connected to a fixed base via a support rod. A first ultrasonic testing probe or a second ultrasonic testing probe is movably mounted on the fixed base. A second driving structure is provided on the fixed base, and the second driving structure drives the first ultrasonic testing probe or the second ultrasonic testing probe to rotate.

[0014] Preferably, the spray flushing assembly includes a spray plate connected to the top of the sealed semi-circular inner cavity, the liquid inlet end of the spray plate is connected to a fluid delivery pipe, the fluid inlet end of the fluid delivery pipe is connected to a liquid inlet pipe and an air inlet pipe, and both the liquid inlet pipe and the air inlet pipe are provided with a one-way valve at their fluid outlet ends.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. This fully automatic flaw detection device for seamless stainless steel pipe weld defects constructs a sealed cavity by wrapping the weld and using a vacuum pump to extract the air from the sealed cavity. This prevents air from mixing into or even dissolving in the coupling agent during the flaw detection process and the application of the coupling agent, thus forming microbubbles. This ensures the acoustic energy transmission efficiency of the coupling layer, improves the sensitivity of the detection, and reduces the probability of missed diagnoses.

[0016] 2. This fully automatic flaw detection device for weld defects in seamless stainless steel pipes has automatic application, automatic recycling, and automatic cleaning functions for the coupling agent, realizing unmanned operation of the entire detection process. During the detection process, the slow rotation of the steel pipe eliminates changes in the thickness of the coupling agent caused by gravity, ensuring the stability of the coupling between the probe and the weld and guaranteeing the detection quality. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of a fully automatic flaw detection device for weld defects in seamless stainless steel pipes proposed in this invention. Figure 2 The structure of this invention Figure 1 Rear view illustration; Figure 3 This is a schematic diagram of the structural detection mechanism of the present invention; Figure 4 The structure of this invention Figure 3 The diagram on the right; Figure 5 This is an exploded view of the structural testing mechanism of the present invention; Figure 6 This is a schematic diagram showing the connection between the second driving structure and the fixed base in the present invention; Figure 7 This is a schematic diagram of the interior of the coupling agent storage cylinder of the present invention.

[0018] In the diagram: 1. Steel pipe placement rack; 2. First hydraulic telescopic rod; 3. Sealing semicircle; 4. Fluid delivery pipe; 5. Coupling agent storage cylinder; 6. Ultrasonic flaw detector; 7. Vacuum pump; 8. Vacuum cleaner; 9. Waste liquid collection box; 10. Drain pipe; 11. Second hydraulic telescopic rod; 12. Double-ended ball screw; 13. Drive servo motor; 14. Connecting rod; 15. Outer clamping plate; 16. First drive structure; 17. Inner clamping ring; 18. Liquid replenishment check valve; 19. Third linear movement structure; 20. Extrusion plate; 21. Connecting pipe; 22. Moving rod; 23. Coupling agent application head; 24. Coupling agent recovery head; 25. Fixed seat; 26. Second drive structure; 27. Second ultrasonic detection probe; 28. Recovery pipe; 29. ​​Shielding plate; 30. Inner ring; 31. Spray plate; 32. First ultrasonic detection probe; 33. Support sleeve; 34. Vacuum tube. Detailed Implementation

[0019] 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 skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] This invention provides one embodiment: Please refer to Figures 1-7An automatic flaw detection device for weld defects in seamless stainless steel pipes includes a workbench with steel pipe placement racks 1 at both ends. The top of the steel pipe placement rack 1 is provided with a placement groove adapted to the seamless stainless steel pipe to be tested. The seamless stainless steel pipe to be tested is supported by the steel pipe placement rack 1, and the weld of the steel pipe is located between the two steel pipe placement racks 1.

[0021] A steel pipe fixing and rotating structure is provided on the outer side of the steel pipe placement rack 1. The steel pipe fixing and rotating structure includes two outer clamping plates 15. After the seamless stainless steel pipe to be tested is supported by the steel pipe placement rack 1, the seamless stainless steel pipe is located between the two outer clamping plates 15. The two outer clamping plates 15 are connected to the worktable through a first linear movement structure. The first linear movement structure includes a ball screw pair and a drive servo motor 13 for driving the ball screw pair. The ball screw pair includes a double-ended ball screw 12 that is movably connected to the worktable. 3 drives the double-ended ball screw 12 to rotate. Both ends of the double-ended ball screw 12 are provided with matching ball nuts on their outer rings. The outer ring of the ball nuts is fixedly connected to a connecting rod 14. The top of the connecting rod 14 is connected to an outer clamping plate 15. When the double-ended ball screw 12 rotates, the matching ball nuts can move in their direction. When the ball nuts move, they can drive the connecting rod 14 to move. The connecting rod 14 drives the outer clamping plate 15 to move, changing the distance between the two outer clamping plates 15.

[0022] Both outer clamping plates 15 have movably mounted inner clamping rings 17 on their inner sidewalls. Under the action of the first linear movement structure, the two inner clamping rings 17 can clamp and fix the steel pipe. At this time, the two inner clamping rings 17 form an active rotating ring. A first driving structure 16 is provided on the outer side of one outer clamping plate 15. The active rotating ring is driven to rotate by the first driving structure 16. When the first driving structure 16 drives the active rotating ring to rotate, the active rotating ring can drive the seamless stainless steel pipe to rotate. The first driving structure 16 can be a servo motor, and the model and specifications can be set according to requirements. The seamless stainless steel pipe is in a slow rotation state, and the rotation speed can be set according to requirements.

[0023] A detection mechanism is set between the two steel pipe placement racks. The detection mechanism includes two openable and closable sealed semicircles 3. In this embodiment, the first hydraulic telescopic rod 2 is used to drive the sealed semicircles 3 to move. Specifically, the output shaft end of the first hydraulic telescopic rod 2 is connected to the outer wall of the sealed semicircle 3, and the first hydraulic telescopic rod 2 is fixedly connected to the worktable.

[0024] When the two sealing semicircles 3 are closed, they together with the outer wall of the steel pipe to form a sealing cavity. The weld of the stainless steel pipe is located inside the sealing cavity, and the end of the sealing semicircle 3 is movably fitted with an inner ring 30. The sealing semicircle 3 is tightly fitted with the steel pipe through the inner ring 30, and the sealing semicircle 3 and the inner ring 30 are sealed by a sealing lip. Sealing gaskets are pre-installed between the two inner rings 30 and the steel pipe, the mating end faces of the two inner rings 30 and the mating end faces of the two sealing semicircles 3. The sealing gaskets and sealing lips are used to ensure the sealing performance of the sealing cavity. The material and structure of the sealing gaskets and sealing lips can be set according to requirements.

[0025] A vacuuming structure is installed on the workbench, with its air inlet extending into the sealed cavity. Specifically, the vacuuming structure includes a vacuum pump 7 and a vacuum tube 34 connected to the air inlet of the vacuum pump 7. The air inlet of the vacuum tube 34 is connected to a sealed semicircle 3, and a one-way valve is installed at the air inlet of the vacuum tube 34. When the vacuum pump 7 is working, the one-way valve is open, allowing the vacuum pump 7 to remove air from the sealed cavity until the vacuum level in the sealed cavity reaches a preset value. A vacuum sensor is installed inside the sealed cavity to monitor the vacuum level in real time using a suitable model and specification of vacuum sensor, and the collected data is fed back to the controller of this application. When the vacuum level in the sealed cavity reaches the required level, the controller controls the vacuum pump 7 to stop working. When the vacuum pump 7 stops working, the one-way valve is closed, ensuring the vacuum level in the sealed cavity.

[0026] Coupling agent application and recovery components are provided on both sides of one end of the sealing cavity. The coupling agent application and recovery components include a coupling agent application head 23 and a coupling agent recovery head 24 that are movably connected to the sealing cavity. The coupling agent recovery head 24 is connected to the sealing cavity through a second linear moving structure. In this embodiment, the second linear moving structure includes a second hydraulic telescopic rod 11, which is connected to the outer wall of the sealing semicircle 3. The output shaft end of the second hydraulic telescopic rod 11 is connected to the coupling agent recovery head 24 through a moving rod 22. The moving rod 22 is movably connected to the sealing semicircle 3, and a first telescopic sleeve is used to seal the gap between the moving rod 22 and the sealing semicircle 3. The first telescopic sleeve is located on the outside of the sealing semicircle 3. One end of the first telescopic sleeve is fixedly sleeved on the outer ring of the moving rod 22, and the other end of the first telescopic sleeve is connected to the outer wall of the sealing semicircle 3. The first telescopic sleeve is used to tightly seal the gap between the moving rod 22 and the sealing semicircle 3, ensuring the sealing performance of the sealing semicircle 3. The material of the first telescopic sleeve can be set according to requirements.

[0027] The end of the coupling agent recovery head 24 away from the moving rod 22 is connected to the coupling agent application head 23. The two coupling agent recovery heads 24 are symmetrically arranged in the sealed cavity, and the two coupling agent application heads 23 are symmetrically arranged in the sealed cavity. The inner walls of both the coupling agent application head 23 and the coupling agent recovery head 24 are arc-shaped surfaces with the same inner diameter. When the two coupling agent application heads 23 are closed, an annular gap is formed between them and the steel pipe. The thickness of the annular gap is the same as the thickness of the applied coupling agent.

[0028] A coupling agent storage cylinder 5 and a vacuum cleaner 8 are installed outside the sealed cavity. The liquid outlet of the coupling agent storage cylinder 5 is connected to the liquid inlet of the coupling agent application head 23 through a connecting pipe 21. The connecting pipe 21 is movably connected to the sealing semicircle 3. One end of the connecting pipe 21 is connected to the liquid inlet of the coupling agent application head 23, and the other end of the connecting pipe 21 is located outside the sealing semicircle 3 and is connected to the liquid outlet of the coupling agent storage cylinder 5. The gap between the connecting pipe 21 and the sealing semicircle 3 is sealed by a second telescopic sleeve. The second telescopic sleeve is located outside the sealed cavity. One end of the second telescopic sleeve is fixedly sleeved on the outer ring of the connecting pipe 21, and the other end is connected to the outer side of the sealing semicircle 3. The material and structure of the second telescopic sleeve can be set according to requirements.

[0029] The outer ring of the coupling agent storage cylinder 5 is movably fitted with a support sleeve 33, which is connected to the outer surface of the sealing semicircle 3. When the first linear moving structure drives the coupling agent recovery head 24 to move, the coupling agent recovery head 24 can drive the coupling agent application head 23 to move. The coupling agent application head 23 can drive the coupling agent storage cylinder 5 to move through the connecting pipe 21, changing the position of the coupling agent storage cylinder 5. The coupling agent storage cylinder 5 can only move along the extension and retraction direction of the first linear moving structure.

[0030] The coupling agent storage cylinder 5 is equipped with a replenishment check valve 18 at its inlet end. When the replenishment check valve 18 is open, coupling agent of appropriate cost can be injected into the coupling agent storage cylinder 5 to replenish the coupling agent. The type of coupling agent can be set according to requirements. A squeezing plate 20 is movably connected to the inner cavity of the coupling agent storage cylinder 5. The squeezing plate 20 is connected to the coupling agent storage cylinder 5 through a third linear moving structure 19. The third linear movement structure 19 can be a hydraulic telescopic rod. Under the action of the third linear movement structure 19, the position of the extrusion plate 20 in the coupling agent storage cylinder 5 can change. When the extrusion plate 20 is close to the liquid outlet end of the coupling agent storage cylinder 5, the coupling agent can be extruded by the extrusion plate 20. The extruded coupling agent can enter the coupling agent application head 23 through the connecting pipe 21. The coupling agent in the coupling agent application head 23 can be discharged through the one-way valve set on its arc surface. When the coupling agent application head 23 is sleeved outside the weld under the action of the first linear movement, the discharged coupling agent can be discharged into the annular gap, thereby achieving the purpose of applying coupling agent to the weld of stainless steel pipe. In use, the controller controls the extension and retraction of the third linear movement structure 19 so that the coupling agent application head 23 discharges the coupling agent in a quantitative manner, thereby controlling the coating thickness of the coupling agent.

[0031] The coupling agent recovery head 24 is connected to the fluid inlet of the vacuum cleaner 8 via a recovery pipe 28. One end of the recovery pipe 28 is connected to the fluid outlet of the coupling agent recovery head 24, and the other end is connected to the fluid inlet of the vacuum cleaner 8. The vacuum cleaner 8 is connected to the workbench. When the controller controls the vacuum cleaner 8 to work, the one-way valve on the arc-shaped surface of the coupling agent recovery head 24 can be in the open state. Under the action of suction, the coupling agent applied to the outside of the weld can enter the inner cavity of the coupling agent recovery head 24 and enter the vacuum cleaner 8 along the recovery pipe 28, and be discharged directionally from the fluid outlet of the vacuum cleaner 8, realizing the recovery of the coupling agent applied to the outside of the weld. Furthermore, after the weld defect detection is completed, the coupling agent is recovered. During the coupling agent recovery process, the two sealing semicircles 3 are in a separated state, so that the distance between the coupling agent recovery head 24 and the weld reaches a preset value, allowing outside air to enter between the two sealing semicircles 3, which facilitates the negative pressure recovery of the coupling agent.

[0032] Furthermore, a baffle plate 29 is provided on the side of the sealed semicircle 3 away from the first ultrasonic testing probe 32. The baffle plate 29 is connected to the sealed semicircle 3 via a straight rod. The inner diameter of the baffle plate 29 is larger than the outer diameter of the steel pipe. The outer wall of the baffle plate 29 is adapted to the arc-shaped surface. The thickness of the baffle plate 29 is less than the thickness of the coupling agent application. The thickness of the baffle plate 29 can be set according to requirements. A scraper is provided at the end of the baffle plate 29 away from the second linear moving structure. With the baffle plate 29, when the arc-shaped surface passes the scraper, the scraper can remove the excess coupling agent adhering to the arc-shaped surface, maintaining the cleanliness of the arc-shaped surface and reducing the difficulty of subsequent cleaning. The arc-shaped surface and the outer wall of the baffle plate 29 can be in a close fit. The baffle plate 29 protects the one-way valves provided on the arc-shaped surface of the coupling agent recovery head 24 and the one-way valves provided on the coupling agent application head 23, reducing the probability of oxidation and drying curing of residual coupling agent in the one-way valves, ensuring the unobstructed flow of the one-way valves, and facilitating the use of this application.

[0033] A first ultrasonic testing probe 32 is installed on one side of a coupling agent coating and recovery assembly, and a second ultrasonic testing probe 27 is installed on one side of another coupling agent coating and recovery assembly. The first ultrasonic testing probe 32 and the second ultrasonic testing probe 27 are arranged opposite to each other. An ultrasonic flaw detector 6 is installed on the worktable. The ultrasonic flaw detector 6 is connected to the corresponding first ultrasonic testing probe 32 or second ultrasonic testing probe 27 through a probe wire. The part of the probe wire inside the sealed cavity is spiral-shaped to facilitate the movement of the ultrasonic testing probe within the sealed cavity. The first ultrasonic testing probe 32 is used to detect internal defects in the weld, and the second ultrasonic testing probe 27 is used for high-sensitivity detection of surface and near-surface microcracks in the weld. The synergistic effect of the first ultrasonic testing probe 32 and the second ultrasonic testing probe 27 can achieve comprehensive detection of weld defects. The models and specifications of both can be set according to requirements.

[0034] The side of the coupling agent application head 23 furthest from the coupling agent recovery head 24 is connected to a fixed base 25 via a support rod. A first ultrasonic testing probe 32 or a second ultrasonic testing probe 27 is movably mounted on the fixed base 25. A second drive structure 26 is provided on the fixed base 25, driving the first ultrasonic testing probe 32 or the second ultrasonic testing probe 27 to rotate. The second drive structure 26 can be a servo motor, which drives the first ultrasonic testing probe 32 or the second ultrasonic testing probe 27 to rotate via a gear set. The model and specifications of the servo motor can be set according to requirements and are not limited here.

[0035] A spray rinsing assembly is installed inside the sealed cavity. The spray rinsing assembly includes a spray plate 31 connected to the top of the inner cavity of the sealed semicircle 3. The liquid inlet end of the spray plate 31 is connected to a fluid delivery pipe 4. The fluid inlet end of the fluid delivery pipe 4 is connected to a liquid inlet pipe and an air inlet pipe. Both the liquid inlet pipe and the air inlet pipe are equipped with one-way valves at their fluid outlet ends. When the two sealed semicircles 3 and the stainless steel together form a sealed cavity, the spray plate 31 is located above the weld. After the coupling agent is recovered, a suitable cleaning solution is delivered to the fluid delivery pipe 4 through the liquid inlet pipe. The cleaning solution in the fluid delivery pipe 4 is delivered to the inner cavity of the spray plate 31 and sprayed out through the spray holes provided on the inner side wall of the spray plate 31. During the spraying process, both ultrasonic detection probes are located in the spraying area, and the controller controls the second drive structure 26 to work, so that the two upward-facing detection probes rotate slowly in opposite directions to achieve the rinsing of the coupling agent adhering to the surface of the ultrasonic detection probes. The weld and the scraper are both located in the spraying area to achieve the cleaning of the coupling agent adhering to the surface of the weld and the surface of the scraper. After the coupling agent cleaning is completed, the supply of cleaning fluid is stopped, and dry gas at a suitable temperature is delivered to the fluid delivery pipe 4 through the air inlet pipe. The dry gas in the fluid delivery pipe 4 is then delivered to the inner cavity of the spray plate 31 and sprayed out through the spray holes provided on the inner side wall of the spray plate 31, thereby drying the sprayed components and facilitating its use in this application. Furthermore, the sealing semicircle 3 intercepts the spray splash, reducing the impact of the spray liquid on surrounding components.

[0036] Waste liquid collection box 9 is installed on the workbench. Waste liquid collection box 9 is located below the sealed cavity. A drain pipe 10 is installed on one side of the bottom of the inner cavity of waste liquid collection box 9. Waste liquid generated by spraying can be recycled using waste liquid collection box 9. The recycled waste liquid can be discharged in a specific direction through drain pipe 10.

[0037] All electrical components involved in this application are existing technologies. Those skilled in the art can select appropriate models of electrical components according to their needs. No restrictions or elaborations are made here. Those skilled in the art understand their connection methods. With the help of those skilled in the art, all electrical components in this application and their compatible power supplies are connected by wires. According to the actual situation, appropriate controllers are selected to meet control requirements. For specific connections and control sequences, please refer to the description below. The electrical connections between each electrical component are completed in the order of their operation. The detailed connection methods are well-known technologies in the art. The following mainly introduces the working principle and process, and will not describe the electrical control.

[0038] In summary: When using this fully automatic flaw detection device for weld defects in seamless stainless steel pipes, the stainless steel pipe to be tested is placed on the pipe placement rack 1. The weld of the stainless steel pipe is ground using the existing grinding structure. The weld is located between two sealing semicircles 3. The first linear movement structure drives the outer clamping plate 15 to move, which in turn drives the inner clamping ring 17 to move until the inner clamping ring 17 clamps the pipe. The two inner clamping rings 17 form an active rotating ring. The controller controls the first hydraulic telescopic rod 2 to work, which drives the sealing semicircles 3 to move until the two sealing semicircles 3 close. At this time, the two sealing semicircles 3 and the pipe form a sealed cavity. The controller controls the first drive structure 16 to work, which drives the active rotating ring to rotate. The active rotating ring drives the pipe to rotate. Under the action of friction, the pipe drives the inner ring 30 to rotate. The vacuum pump 7 works to remove the air in the sealed cavity until the sealed cavity reaches the preset vacuum level.

[0039] The controller controls the second linear movement structure to move the coupling agent application head 23 until it reaches the weld location. The two coupling agent application heads 23 and the steel pipe form an annular gap. The third linear movement structure 19 then operates, driving the extrusion plate 20 to extrude the coupling agent. Under the extrusion force, the coupling agent enters the coupling agent application head 23 through the connecting pipe 21. The coupling agent inside the application head 23 can be discharged through a one-way valve on its arc-shaped surface. Furthermore, when the coupling agent application head 23 is positioned outside the weld under the action of the first linear movement, the discharged coupling agent can be discharged into the annular gap, achieving the purpose of applying coupling agent to the stainless steel pipe weld. After the coupling agent application is completed, the third linear movement... The two linear moving structures drive the coupling agent application head 23 to move in the opposite direction. The coupling agent application head 23 drives the fixed base 25 to move through the support rod until both the first ultrasonic testing probe 32 and the second ultrasonic testing probe 27 move to the weld. A coupling agent of a preset thickness is placed between the ultrasonic testing probe and the weld. This application uses the first ultrasonic testing probe 32 to detect internal defects in the weld and the second ultrasonic testing probe 27 to detect microcracks on the surface and near the surface of the weld with high sensitivity. The synergistic effect of the first ultrasonic testing probe 32 and the second ultrasonic testing probe 27 can achieve comprehensive detection of weld defects. In addition, during the detection process, the slow rotation of the steel pipe can avoid the thickness of the coupling agent fluctuating due to gravity, ensuring the stability of the probe coupling degree, and thus ensuring the reliability of weld defect detection.

[0040] After the weld defect is detected, the first hydraulic telescopic rod 2 moves the two sealing semicircles 3 away from each other. The sealing semicircles 3 move the coupling agent recovery head 24 connected to them until the distance between the coupling agent recovery head 24 and the weld meets the requirements. During the operation of the first hydraulic telescopic rod 2, the second linear movement structure drives the coupling agent recovery head 24 to work, so that the coupling agent recovery head 24 moves to the location of the weld. When the vacuum cleaner 8 is working, the one-way valve set on the arc surface of the coupling agent recovery head 24 can be in the open state. Under the action of suction, the coupling agent applied to the outside of the weld can enter the inner cavity of the coupling agent recovery head 24 and enter the vacuum cleaner 8 along the recovery pipe 28. It is then discharged directionally from the fluid discharge end of the vacuum cleaner 8, realizing the recovery of the coupling agent applied to the outside of the weld.

[0041] After the coupling agent is recovered, the second linear moving structure drives the ultrasonic testing probe to move until the two ultrasonic testing probes move to the spray area. The spray rinsing assembly is used to spray and rinse the coupling agent adhering to the ultrasonic testing probes, welds and scraper surfaces and dry them with airflow, so as to facilitate the reuse of this application.

[0042] All standard parts used in this invention are commercially available products, and irregularly shaped parts can be customized according to the specifications and drawings. All specific connection methods of the structures adopt well-known and mature technologies in the art, such as bolt connections. The machinery, parts, and equipment used are all existing models under current technical conditions, and models can be selected according to requirements without limitation. The material, size, and specifications of each component can be selected according to actual needs, and this specification does not limit this. Content not described in detail in this specification belongs to prior art known to those skilled in the art. Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the invention. The scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A fully automatic flaw detection device for weld defects in seamless stainless steel pipes, comprising a workbench, characterized in that: Both ends of the workbench are provided with steel pipe placement racks (1), the steel pipe weld is located between the two steel pipe placement racks (1), and a detection mechanism is provided between the two steel pipe placement racks. The detection mechanism includes two openable and closable sealing semicircles (3). When the two sealing semicircles (3) are closed, they together with the outer wall of the steel pipe form a sealing cavity. The end of the sealing semicircle (3) is movably fitted with an inner ring (30). The sealing semicircle (3) contacts the steel pipe through the inner ring (30). A vacuum structure is provided on the workbench. The air inlet of the vacuum structure extends into the sealing cavity. Coupling agent coating and recovery components are provided on both sides of one end of the sealing cavity. A first ultrasonic detection probe (32) is provided on one side of one coupling agent coating and recovery component, and a second ultrasonic detection probe (27) is provided on one side of the other coupling agent coating and recovery component. The first ultrasonic detection probe (32) and the second ultrasonic detection probe (27) are arranged opposite to each other. A spray rinsing component is provided in the sealing cavity. The coupling agent application and recovery assembly includes a coupling agent application head (23) and a coupling agent recovery head (24) that are movably connected to the sealed cavity. The coupling agent recovery head (24) is connected to the sealed cavity through a second linear moving structure. A coupling agent storage cylinder (5) and a vacuum cleaner (8) are provided outside the sealed cavity. The liquid outlet of the coupling agent storage cylinder (5) is connected to the liquid inlet of the coupling agent application head (23) through a connecting pipe (21). The coupling agent recovery head (24) is connected to the fluid inlet of the vacuum cleaner (8).

2. The fully automatic flaw detection device for weld defects in seamless stainless steel pipes according to claim 1, characterized in that: The steel pipe placement rack (1) is provided with a steel pipe fixing and rotating structure on its outer side. The steel pipe fixing and rotating structure includes two outer clamping plates (15). The steel pipe is located between the two outer clamping plates (15). The two outer clamping plates (15) are connected to the workbench through a first linear moving structure. The inner sidewalls of the two outer clamping plates (15) are movably provided with inner clamping rings (17). A first driving structure (16) is provided on the outer side of one of the outer clamping plates (15). When the two steel pipe fixing and rotating structures clamp and fix the steel pipe, the two inner clamping rings (17) form an active rotating ring. The active rotating ring is driven to rotate by the first driving structure (16).

3. The fully automatic flaw detection device for weld defects in seamless stainless steel pipes according to claim 1, characterized in that: The vacuuming structure includes a vacuum pump (7) and a vacuum tube (34) connected to the air inlet of the vacuum pump (7). The air inlet of the vacuum tube (34) is connected to a sealed semicircle (3), and a one-way valve is provided at the air inlet of the vacuum tube (34).

4. The fully automatic flaw detection device for weld defects in seamless stainless steel pipes according to claim 1, characterized in that: The outer ring of the coupling agent storage cylinder (5) is movably fitted with a support sleeve (33), which is connected to the outer surface of the sealing semicircle (3); the inlet end of the coupling agent storage cylinder (5) is provided with a replenishing one-way valve (18), and the inner cavity of the coupling agent storage cylinder (5) is movably connected with a squeezing plate (20), which is connected to the coupling agent storage cylinder (5) through a third linear moving structure (19).

5. The fully automatic flaw detection device for weld defects in seamless stainless steel pipes according to claim 1, characterized in that: A waste liquid collection box (9) is provided on the workbench. The waste liquid collection box (9) is located below the sealed cavity. A drain pipe (10) is provided on one side of the bottom end of the inner cavity of the waste liquid collection box (9).

6. The fully automatic flaw detection device for weld defects in seamless stainless steel pipes according to claim 1, characterized in that: The inner walls of both the coupling agent application head (23) and the coupling agent recovery head (24) are arc-shaped, with the same inner diameter. When the two coupling agent application heads (23) are closed, an annular gap is formed between them and the steel pipe. The thickness of the annular gap is the same as the thickness of the applied coupling agent.

7. The fully automatic flaw detection device for weld defects in seamless stainless steel pipes according to claim 6, characterized in that: A shield (29) is provided on the side of the sealing semicircle (3) away from the first ultrasonic detection probe (32). The shield (29) is connected to the sealing semicircle (3) by a straight rod. The inner diameter of the shield (29) is greater than the outer diameter of the steel pipe. The outer wall of the shield (29) is adapted to the arc surface. The thickness of the shield (29) is less than the thickness of the coupling agent coating.

8. The fully automatic flaw detection device for weld defects in seamless stainless steel pipes according to claim 1, characterized in that: The side of the coupling agent application head (23) away from the coupling agent recovery head (24) is connected to a fixed base (25) via a support rod. A first ultrasonic detection probe (32) or a second ultrasonic detection probe (27) is movably mounted on the fixed base (25). A second driving structure (26) is provided on the fixed base (25). The second driving structure (26) drives the first ultrasonic detection probe (32) or the second ultrasonic detection probe (27) to rotate.

9. The fully automatic flaw detection device for weld defects in seamless stainless steel pipes according to claim 1, characterized in that: The spray flushing assembly includes a spray plate (31) connected to the top of the inner cavity of the sealed semicircle (3). The inlet end of the spray plate (31) is connected to a fluid delivery pipe (4). The fluid inlet end of the fluid delivery pipe (4) is connected to an inlet pipe and an air inlet pipe. Both the inlet pipe and the air inlet pipe are equipped with a one-way valve at their fluid outlet ends.

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