Non-destructive testing device for welding seam of pressure vessel

Abstract

The invention discloses a pressure vessel welding seam nondestructive testing device, and relates to the technical field of pressure vessel detection. The device comprises a base, an arc-shaped groove used for bearing a spherical container is formed in the center of the base, a first movable plate is arranged on the base through an annular moving mechanism, the annular moving mechanism drives the first movable plate to rotate around the circle center of the spherical container, and an arc-shaped plate matched with the curvature of the outer wall of the spherical container is arranged on the first movable plate; a second movable plate is arranged on the arc-shaped plate through an arc moving mechanism; the spherical container is placed in the arc-shaped groove in the base, the annular moving mechanism drives the first movable plate to rotate, the arc moving mechanism drives the second movable plate to move in an arc-shaped mode, the annular moving and the arc moving can enable the detection head to move on the surface of the spherical container at two degrees of freedom, it is ensured that the detection head can cover all types of welding seams, and meanwhile the detection efficiency is improved. Oxide skin on the welding seam is cleaned and removed through the cleaning mechanism, so that the lift-off distance between the detection head and the container is prevented from being influenced by the oxide skin.

Description

Technical Field

[0001] This invention relates to the field of pressure vessel inspection technology, specifically to a non-destructive testing device for pressure vessel welds. Background Technology

[0002] Pressure vessels are closed devices that hold gases or liquids and bear a certain pressure. Their safety and reliability are of paramount importance. As a key part of the pressure vessel structure, the quality of the weld directly affects the performance and service life of the entire equipment. Therefore, it is necessary to inspect the weld. The main purpose of weld inspection is to find various defects in the weld, such as cracks, slag inclusions, lack of fusion, and incomplete penetration. These defects may cause the equipment to leak or rupture under high pressure, high temperature or corrosive environment, thereby causing safety accidents. Traditional non-destructive testing (NDT) devices typically consist of a ring-shaped frame that can move up and down along the surface of a container, with a rotating inspection head mounted on the frame. Such devices are generally designed for cylindrical pressure vessels. However, for specialized pressure vessels, such as spherical tanks (primarily used for storing and transporting gases, liquids, and liquefied gases), which have a spherical structure and the highest load-bearing capacity for the same wall thickness (requiring only half the wall thickness of a cylindrical vessel of the same diameter), and with the smallest surface area, spherical tanks experience uniform stress and are suitable for high-pressure storage, traditional testing devices cannot effectively inspect the welds of these pressure vessels. Therefore, this invention proposes a non-destructive testing device for pressure vessel welds. Summary of the Invention

[0003] The purpose of this invention is to provide a non-destructive testing device for pressure vessel welds in order to solve the problems mentioned above in the background art.

[0004] To achieve the above objectives, the present invention specifically adopts the following technical solution: A non-destructive testing device for pressure vessel welds, comprising: The base has an arc-shaped groove at its center for supporting the spherical container. A first movable plate is provided on the base via a ring-moving mechanism, which drives the first movable plate to rotate around the center of the spherical container. An arc-shaped plate adapted to the curvature of the outer wall of the spherical container is provided on the first movable plate. A second movable plate is provided on the arc-shaped plate via an arc-moving mechanism, which drives the second movable plate to move along its arc. A probe for inspecting the weld is provided on the second movable plate. The cleaning mechanism, located on the second movable plate, is used to clean the weld seams of the spherical shaper.

[0005] Furthermore, the inner wall of the arc-shaped groove is provided with a suction cup, and the suction cup is connected to a vacuum pump installed on the base through a delivery pipe.

[0006] Furthermore, the ring-moving mechanism includes an annular slide rail and a bevel gear ring fixed on the base and concentrically distributed. A first movable plate is slidably sleeved on the annular slide rail. A first motor is provided on the first movable plate. The output shaft of the first motor is fixed with a bevel gear that meshes with the teeth of the bevel gear ring.

[0007] Furthermore, the arc-moving mechanism includes an arc-shaped slide rail and an arc-shaped rack fixed on the arc-shaped plate, a second movable plate slidably sleeved on the arc-shaped slide rail, a second motor provided on the second movable plate, and a circular gear that meshes with the teeth of the arc-shaped rack fixed on the output shaft of the second motor.

[0008] Furthermore, a lead screw is threaded through the second movable plate, and a mounting base is rotatably connected to the end of the lead screw. A guide rod with its end sliding through the second movable plate is fixed on the mounting base, and the probe head and cleaning mechanism are both located on the mounting base.

[0009] Furthermore, the cleaning mechanism includes a mounting frame rotatably mounted on a mounting base, a brush plate being provided on the mounting frame, a driven gear being fixedly mounted on the mounting frame, a third motor being fixedly mounted on the mounting base, and a transmission gear meshing with the teeth of the driven gear being fixedly mounted on the output shaft of the third motor.

[0010] Furthermore, the mounting bracket includes a support rotatably mounted on the mounting base, a sleeve fixedly mounted on the support, an inner rod movably inserted into the sleeve, a spring and a damper connecting the sleeve and the inner rod, and a brush plate located at the end of the inner rod.

[0011] Furthermore, the brush plate has an arc-shaped groove, and the inner rod has a ball that is rolled and inserted into the arc-shaped groove. Several tension springs arranged in a ring are connected between the inner rod and the brush plate.

[0012] Furthermore, a groove is provided on the first movable plate, a slider is slidably disposed in the groove, an arc plate is fixed on the slider, and an electric push rod is connected between the first movable plate and the slider.

[0013] Furthermore, a protective shell is installed on the first movable plate, which covers the annular slide rail and the conical tooth ring.

[0014] The beneficial effects of this invention are as follows: In this invention, a spherical container is placed in an arc-shaped groove on a base. A circumferential movement mechanism drives the first movable plate to rotate, and an arc-shaped movement mechanism drives the second movable plate to move in an arc. The circumferential movement and the arc-shaped movement allow the probe head to move in two degrees of freedom on the surface of the spherical container, ensuring that the probe head can cover all types of welds. At the same time, before detection, the oxide scale on the weld is removed by a cleaning mechanism to avoid affecting the lifting distance between the probe head and the container, thereby ensuring the detection effect.

[0015] In this invention, the position of the brush plate can be flexibly adjusted to accommodate the pre-inspection cleaning of welds at different locations. At the same time, by utilizing the cooperation of the spring telescopic rod and the damper, it can not only adapt to cleaning at different curvature positions, but also buffer and reduce the frictional vibration force generated by cleaning, thereby ensuring stable detection by the probe. Attached Figure Description

[0016] Figure 1 This is a three-dimensional structural diagram of the present invention; Figure 2 This is another three-dimensional structural diagram of the present invention; Figure 3 This is a three-dimensional structural cross-sectional view of the present invention; Figure 4 This is an exploded view of part of the three-dimensional structure of the present invention; Figure 5 This is another part of the three-dimensional structural diagram of the present invention; Figure 6 This is another three-dimensional structural diagram of the present invention; Figure 7 This is a three-dimensional structural cross-sectional view of another part of the present invention; Figure 8 This is the present invention. Figure 6 Enlarged view of point A in the middle; Figure 9 This is the present invention. Figure 7 Enlarged view of section B in the middle.

[0017] Reference numerals: 1. Base; 2. Arc-shaped groove; 3. Circumferential movement mechanism; 4. First movable plate; 5. Arc-shaped plate; 6. Arc-shaped movement mechanism; 7. Second movable plate; 8. Probe head; 9. Cleaning mechanism; 10. Suction cup; 11. Conveying pipe; 12. Vacuum pump; 13. Arc-shaped groove; 14. Sphere; 15. Tension spring; 16. Slide groove; 17. Slider; 18. Electric push rod; 19. Protective shell; 20. Lead screw; 21. Mounting base; 22. Guide rod; 301. Circular slide rail; 302. Bevel gear ring; 303. First motor; 304. Bevel gear; 601. Arc-shaped slide rail; 602. Arc-shaped rack; 603. Second motor; 604. Circular gear; 901. Mounting bracket; 902. Brush plate; 903. Driven gear; 904. Third motor; 905. Transmission gear; 9011. Bracket; 9012. Sleeve; 9013. Inner rod; 9014. Spring; 9015. Damper. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0019] like Figures 1-9 As shown, an embodiment of the pressure vessel weld non-destructive testing device of the present invention includes: The base 1 has a centrally constructed arc-shaped groove 2 for supporting the spherical container. Preferably, the base 1 includes a base plate and a base column disposed at the center of the base plate, with the arc-shaped groove 2 formed at the top of the base column. Figure 2 As shown, when the spherical container is placed in the arc-shaped groove 2, it has a certain height difference with the base plate. A first movable plate 4 is set on the base 1 through a ring-moving mechanism 3. The ring-moving mechanism 3 drives the first movable plate 4 to rotate around the center of the spherical container. An arc-shaped plate 5 adapted to the curvature of the outer wall of the spherical container is set on the first movable plate 4. A second movable plate 7 is set on the arc-shaped plate 5 through an arc-moving mechanism 6. The arc-moving mechanism 6 drives the second movable plate 7 to move along its arc direction. A probe head 8 for inspecting the weld is set on the second movable plate 7. Preferably, the probe head 8 is an electromagnetic ultrasonic probe, which directly excites ultrasonic waves in the workpiece through electromagnetic effect, without the need for a coupling agent, and does not contact the spherical container, thus achieving non-contact non-destructive testing. The spherical container is usually manufactured first with several spherical lobes (using metal plates). (and processed into the corresponding curvature), and then several spherical petals are welded to form a spherical container, so that the spherical container has several transverse circumferential seams and several longitudinal arc seams. After the spherical container is placed in the arc groove 2, the probe head 8 approaches the weld but does not contact the weld. The circumferential movement mechanism 3 drives the first movable plate 4 to rotate on the base 1 and around the spherical container as the center. The arc movement mechanism 6 drives the second movable plate 7 to move along the arc direction of the arc plate 5, thereby adjusting the position of the probe head 8. Through the rotation of the first movable plate 4 and the sliding of the second movable plate 7, the circumferential movement and the arc movement can enable the probe head 8 to move in two degrees of freedom on the surface of the spherical container, ensuring that the probe head 8 can cover all types of welds (transverse circumferential seams and longitudinal arc seams), thereby conveniently and effectively inspecting the welds of the spherical container. The cleaning mechanism 9 is mounted on the second movable plate 7 and is used to clean the weld seam of the spherical container. Preferably, to make the scheme more reasonable, the cleaning mechanism 9 is located at the front end of the probe head 8 in actual use, and there is a certain distance between it and the probe head 8. This ensures that the cleaning mechanism 9 is always in front of the probe head 8, whether performing transverse circumferential seam or longitudinal arc seam inspection. The cleaning mechanism 9 does not clean dust and impurities, because the electromagnetic field can penetrate them. It mainly cleans oxide scale. When the container is welded, oxide scale is easily left in the weld seam. Oxide scale will significantly increase the lifting distance between the probe and the container, thereby affecting the inspection effect. Therefore, by setting up the cleaning mechanism 9, the weld seam of the spherical container is cleaned first to remove the oxide scale during inspection, and then the weld seam is inspected by the probe head 8, thereby ensuring the inspection effect. In this scheme, a spherical container is placed in an arc-shaped groove 2 on a base 1. A circumferential movement mechanism 3 drives the first movable plate 4 to rotate, and an arc-shaped movement mechanism 6 drives the second movable plate 7 to move in an arc. The circumferential movement and the arc-shaped movement allow the probe head 8 to move in two degrees of freedom on the surface of the spherical container, ensuring that the probe head 8 can cover all types of welds. At the same time, before inspection, the oxide scale on the weld is removed by a cleaning mechanism 9 to avoid affecting the lifting distance between the probe head 8 and the container, thereby ensuring the inspection effect.

[0020] like Figure 3 As shown, the present invention discloses a further technical solution for the base 1. A suction cup 10 is provided on the inner wall of the arc-shaped groove 2. The suction cup 10 is connected to a vacuum pump 12 provided on the base 1 through a delivery pipe 11. Preferably, the suction cup 10 is constructed as an arc-shaped disk, which is adapted to the curvature of the arc-shaped groove 2. When the spherical container is placed in the arc-shaped groove 2, the spherical container just contacts the adsorption surface of the suction cup 10. The vacuum pump 12 does work, and the suction cup 10 generates suction force through the delivery pipe 11, thereby adsorbing and fixing the spherical container. This reduces the contact area of ​​the spherical container, does not affect the inspection of its weld seams, and improves the stability of its fixation.

[0021] like Figure 4 The specific structure of the annular transfer mechanism 3 of the present invention is disclosed. The annular transfer mechanism 3 includes an annular slide rail 301 and a bevel gear ring 302 fixed on the base 1 and arranged concentrically. A first movable plate 4 is slidably sleeved on the annular slide rail 301. A first motor 303 is provided on the first movable plate 4. The output shaft of the first motor 303 is fixed with a bevel gear 304 that meshes with the teeth of the bevel gear ring 302. Preferably, the longitudinal section of the annular slide rail 301 is T-shaped, so that the first movable plate 4 can slide along it in the circumferential direction, but cannot disengage from the annular slide rail 301. When the first motor 303 does work, its output shaft drives the bevel gear 304 to rotate. Since the bevel gear ring 302 is fixed, the meshing of the teeth of the bevel gear 304 and the bevel gear ring 302 achieves the effect of driving the first movable plate 4 to slide along the annular slide rail 301, thereby driving the first movable plate 4 to rotate around the spherical container, thereby detecting the transverse annular seam.

[0022] like Figure 5The specific structure of the arc-shifting mechanism 6 of the present invention is disclosed. The arc-shifting mechanism 6 includes an arc-shaped slide rail 601 and an arc-shaped rack 602 fixed on the arc-shaped plate 5. A second movable plate 7 is slidably sleeved on the arc-shaped slide rail 601. A second motor 603 is provided on the second movable plate 7. The output shaft of the second motor 603 is fixedly provided with a circular gear 604 that meshes with the teeth of the arc-shaped rack 602. Preferably, a through groove is provided through the arc-shaped plate 5. The arc-shaped slide rail 601 and the arc-shaped rack 602 are located on both sides of the through groove. The cross-section of the arc-shaped slide rail 601 is T-shaped. When the second motor 603 does work, its output shaft drives the circular gear 604 to rotate. Since the arc-shaped rack 602 is fixed, the meshing of the teeth of the circular gear 604 and the arc-shaped rack 602 achieves the effect of driving the second movable plate 7 to slide along the arc-shaped plate 5. This not only changes the height of the probe head 8 to detect transverse circumferential seams of different heights, but also detects longitudinal arc seams.

[0023] like Figure 6 and Figure 7 As shown, the present invention discloses a further technical solution for the probe head 8 and the cleaning mechanism 9. A lead screw 20 is threaded through the second movable plate 7, and a mounting base 21 is rotatably connected to the end of the lead screw 20. A guide rod 22 with its end sliding through the second movable plate 7 is fixed on the mounting base 21. The probe head 8 and the cleaning mechanism 9 are both located on the mounting base 21. By twisting the lead screw 20 to rotate and move, the sliding guidance of the guide rod 22 can adjust the stable movement of the mounting base 21. By setting the probe head 8 and the cleaning mechanism 9 on the mounting base 21, the positions of the probe head 8 and the cleaning mechanism 9 can be finely adjusted in actual use, and the lifting distance between the probe head 8 and the spherical container can be finely adjusted to ensure the accuracy of the detection results, thereby further improving practicality.

[0024] like Figure 8 and Figure 9The specific structure of the arc-moving mechanism 6 of the present invention is disclosed. The cleaning mechanism 9 includes a mounting frame 901 rotatably sleeved on the mounting base 21. A brush plate 902 is provided on the mounting frame 901. A driven gear 903 is fixed on the mounting frame 901. A third motor 904 is fixed on the mounting base 21. A transmission gear 905 that meshes with the teeth of the driven gear 903 is fixed on the output shaft of the third motor 904. Preferably, the brush plate 902 includes a plate body. A plurality of bristles are arranged in an array on the side of the plate body facing the container. The bristles can be made of rubber bristles with a certain strength and toughness. The mounting base 21 includes two parallel support plates. A guide post is fixed between the two support plates. A sleeve is fixed on the mounting frame 901. The sleeve rotates... The driven gear 903 is fixed on the sleeve and mounted on the guide post. The third motor 904 performs work, and its output shaft drives the transmission gear 905 to rotate. Through the meshing of the teeth of the transmission gear 905 and the driven gear 903, the mounting bracket 901 can be rotated, thereby adjusting the position of the brush plate 902. This ensures that the brush plate 902 can be located in front of the probe head 8 when performing transverse circumferential seam detection or longitudinal arc seam detection. Preferably, when performing longitudinal arc seam detection, the detection is carried out from top to bottom, that is, the brush plate 902 is located below the probe head 8 to prevent the oxide sheet that falls off from the brush from affecting the detection of the probe head 8. When performing transverse circumferential seam detection, the brush plate 902 can be located on the left and right sides of the probe head 8.

[0025] like Figure 9 The specific structure of the mounting bracket 901 of the present invention is disclosed. The mounting bracket 901 includes a support 9011 rotatably sleeved on the mounting base 21, a sleeve 9012 fixedly mounted on the support 9011, an inner rod 9013 movably inserted into the sleeve 9012, a spring 9014 and a damper 9015 connecting the sleeve 9012 and the inner rod 9013, and a brush plate 902 located at the end of the inner rod 9013. Preferably, the spring 9014 is located inside the sleeve 9012. The sleeve 9012 and the inner rod... The design of 9013 and spring 9014 forms a spring telescopic rod. The elastic force of spring 9014 allows the brush plate 902 to adaptively conform to the surface of the spherical container, thereby effectively scraping and cleaning the oxide scale of the weld. By setting a damper 9015 between the sleeve 9012 and the inner rod 9013, the damper 9015 is used to buffer and reduce shock, reducing the impact of the vibration force generated by the scraping friction on the probe head 8, thereby ensuring the detection effect of the probe head 8.

[0026] like Figure 9As shown, a further technical solution for the brush plate 902 of the present invention is disclosed. The brush plate 902 has an arc-shaped groove 13. A ball 14 is fixedly inserted into the arc-shaped groove 13 on the inner rod 9013. A plurality of tension springs 15 arranged in a ring are connected between the inner rod 9013 and the brush plate 902. Due to the curvature of the surface of the spherical container, the rolling cooperation between the ball 14 and the arc-shaped groove 13 makes the brush plate 902 and the inner rod 9013 form a ball hinge. Through the elastic pulling of the tension springs 15, the brush plate 902 can also adaptively deflect slightly to ensure that the brush plate 902 can fit the curved surface of the spherical container to achieve the best cleaning effect, thereby improving practicality.

[0027] like Figure 3 As shown, a further technical solution for the arc-shaped plate 5 of the present invention is disclosed. A groove 16 is provided on the first movable plate 4, and a slider 17 is slidably arranged in the groove 16. The arc-shaped plate 5 is fixed on the slider 17. An electric push rod 18 is connected between the first movable plate 4 and the slider 17. For some large spherical containers, they are usually placed by hoisting. By adding a slidable slider 17, the arc-shaped plate 5 is fixed on the slider 17. When installing or removing the spherical container, the electric push rod 18 does work, and its piston end drives the slider 17 to slide, thereby driving the arc-shaped plate 5 to move horizontally. When placing the container, the slider 17 can be driven to slide away from the center of the base 1, thereby increasing the clearance space and facilitating the hoisting and placement of the spherical container. After placement, the slider 17 is pushed back to its original position for testing, thereby improving practicality.

[0028] like Figure 4 As shown, a further technical solution for the ring-moving mechanism 3 of the present invention is disclosed. A protective shell 19 is installed on the first movable plate 4. The protective shell 19 covers the annular slide rail 301 and the conical tooth ring 302. When detecting gaps, the oxide scale scraped off by the brush plate 902 will fall downwards. By setting the protective shell 19, the oxide scale falling downwards is prevented from falling into the gap between the teeth of the conical tooth ring 302, which can ensure the stability of the ring-moving mechanism 3. The arc-shaped rack 602 of the arc-moving mechanism 6 is set on the outer arc surface of the arc plate 5, and the falling oxide scale will not affect it.

[0029] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. This invention discloses a non-destructive testing device for pressure vessel welds, relating to the field of pressure vessel testing technology; this invention includes: The base has a centrally constructed arc-shaped groove for supporting a spherical container. A first movable plate is mounted on the base via a circumferential movement mechanism, which drives the first movable plate to rotate around the center of the spherical container. An arc-shaped plate adapted to the curvature of the outer wall of the spherical container is mounted on the first movable plate, and a second movable plate is mounted on the arc-shaped plate via an arc-shaped movement mechanism. In this invention, the spherical container is placed in the arc-shaped groove on the base. The circumferential movement mechanism drives the first movable plate to rotate, and the arc-shaped movement mechanism drives the second movable plate to move in an arc. The circumferential movement and the arc-shaped movement allow the probe head to move in two degrees of freedom on the surface of the spherical container, ensuring that the probe head can cover all types of welds. At the same time, the oxide scale on the weld is removed by a cleaning mechanism to prevent it from affecting the lift-off distance between the probe head and the container.

2. The pressure vessel weld non-destructive testing device according to claim 1, characterized in that, The inner wall of the arc groove (2) is provided with a suction cup (10), and the suction cup (10) is connected to a vacuum pump (12) provided on the base (1) through a delivery pipe (11).

3. The pressure vessel weld non-destructive testing device according to claim 1, characterized in that, The ring-moving mechanism (3) includes an annular slide rail (301) and a bevel gear ring (302) fixed on the base (1) and arranged concentrically. A first movable plate (4) is slidably sleeved on the annular slide rail (301). A first motor (303) is provided on the first movable plate (4). The output shaft of the first motor (303) is fixed with a bevel gear (304) that meshes with the teeth of the bevel gear ring (302).

4. The pressure vessel weld non-destructive testing device according to claim 1, characterized in that, The arc-moving mechanism (6) includes an arc-shaped slide rail (601) and an arc-shaped rack (602) fixed on the arc plate (5). The second movable plate (7) is slidably sleeved on the arc-shaped slide rail (601). The second movable plate (7) is provided with a second motor (603). The output shaft of the second motor (603) is fixed with a spherical gear (604) that meshes with the teeth of the arc-shaped rack (602).

5. The pressure vessel weld non-destructive testing device according to claim 1, characterized in that, A lead screw (20) is threaded through the second movable plate (7). The end of the lead screw (20) is rotatably connected to a mounting base (21). A guide rod (22) with its end sliding through the second movable plate (7) is fixed on the mounting base (21). The probe (8) and the cleaning mechanism (9) are both located on the mounting base (21).

6. The pressure vessel weld non-destructive testing device according to claim 5, characterized in that, The cleaning mechanism (9) includes a mounting frame (901) rotatably mounted on a mounting base (21), a brush plate (902) is provided on the mounting frame (901), a driven gear (903) is fixed on the mounting frame (901), a third motor (904) is fixed on the mounting base (21), and a transmission gear (905) that meshes with the teeth of the driven gear (903) is fixed on the output shaft of the third motor (904).

7. The pressure vessel weld non-destructive testing device according to claim 6, characterized in that, The mounting bracket (901) includes a support (9011) rotatably sleeved on the mounting base (21), a sleeve (9012) fixed on the support (9011), an inner rod (9013) movably inserted into the sleeve (9012), a spring (9014) and a damper (9015) connecting the sleeve (9012) and the inner rod (9013), and a brush plate (902) located at the end of the inner rod (9013).

8. The pressure vessel weld non-destructive testing device according to claim 7, characterized in that, The brush plate (902) has an arc-shaped groove (13), and the inner rod (9013) has a ball (14) that is rolled and inserted into the arc-shaped groove (13). A number of tension springs (15) arranged in a ring are connected between the inner rod (9013) and the brush plate (902).

9. The pressure vessel weld non-destructive testing device according to claim 1, characterized in that, The first movable plate (4) has a groove (16) and a slider (17) is slidably arranged in the groove (16). An arc plate (5) is fixed on the slider (17). An electric push rod (18) is connected between the first movable plate (4) and the slider (17).

10. The pressure vessel weld non-destructive testing device according to claim 3, characterized in that, A protective shell (19) is installed on the first movable plate (4), and the protective shell (19) covers the annular slide rail (301) and the bevel ring (302).

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