Hydrogen storage well off-site annular and vertical combined non-destructive testing device and testing method

Abstract

The application discloses a hydrogen storage well out-of-well annular and vertical combined nondestructive testing device and a testing method. The device comprises a tubular outer wall retaining wall arranged outside a well shaft in the ground and extending along the length direction of the well shaft. An out-of-well testing space is formed between the outer wall retaining wall and the well shaft. The out-of-well testing space is used to detect defects and damages of the well shaft by using a nondestructive testing technology, and remote operation and data transmission are realized by combining with a digital means. During the testing, 1) the annular testing space is filled with water by a centrifugal pump and a pipeline; 2) the ultrasonic probe is controlled to rotate clockwise along the well shaft by a magnetic control annular adjusting device; 3) after one round of clockwise annular rotation is completed, the ultrasonic probe is moved downward, and then one round of counterclockwise rotation is completed; 4) steps 2 and 3 are repeated until the whole surface area of the well shaft is focused and scanned. The application can more conveniently detect the installation and maintenance of the equipment, and improve the timeliness, reliability and stability of the hydrogen storage well testing.

Description

Technical Field

[0001] This invention relates to the field of hydrogen storage well testing technology, and in particular to a combined non-destructive testing device and method for the outer circumferential and vertical aspects of hydrogen storage wells. Background Technology

[0002] A gas storage well is a vertically buried, tubular structure used to store compressed gas. It belongs to the category of high-pressure vessels within fixed pressure vessels and features high safety, good corrosion resistance, high land utilization efficiency, and significant cost-effectiveness. It has broad application prospects in areas such as CNG refueling stations.

[0003] In recent years, with the global emphasis on clean energy and the rapid development of the hydrogen energy industry, underground hydrogen storage wells, as an emerging method of hydrogen storage, have been initially applied and promoted in China. For example, the Banshan Ring Road Integrated Refueling Station built by Sinopec in Chongqing is the first hydrogen refueling station in China to utilize hydrogen storage well technology. This station has a daily hydrogen supply capacity of 1000 kg and primarily provides refueling services for Chongqing's first batch of hydrogen-powered demonstration buses and urban logistics vehicles. This project not only demonstrates the feasibility of underground hydrogen storage well technology but also provides a demonstration effect for the subsequent construction and renovation of hydrogen refueling stations. As one of the important methods of hydrogen energy storage, underground hydrogen storage wells are expected to be more widely used in the future.

[0004] Hydrogen, as a high-energy-density fuel, is highly flammable and explosive. If leaked into the air and exposed to an ignition source or high temperature, it can cause serious safety accidents such as fires and explosions. As a critical facility for storing hydrogen, the integrity of hydrogen storage wells is paramount. During long-term use, hydrogen storage wells may be affected by environmental factors and stress, leading to a decline in structural performance. Furthermore, hydrogen exhibits strong hydrogen embrittlement, primarily because hydrogen atoms on the metal surface of the storage well form active hydrogen atoms that penetrate into the metal. These hydrogen atoms then combine to form hydrogen molecules within the metal. When these hydrogen molecules accumulate at stress concentration points (such as metal defects or cracks), they further exacerbate stress concentration.

[0005] The hydrogen molecule pressure at stress concentration points, combined with residual stress within the material, forms a combined force. When this combined force exceeds the yield strength of the metallic material, it leads to the formation of cracks. These cracks will continue to propagate under stress, and when the cracks propagate to a certain extent, they will cause partial or overall failure of the hydrogen storage well.

[0006] Therefore, regular or irregular inspections of high-pressure underground hydrogen storage wells to promptly identify and address potential problems are crucial for ensuring their safe operation. Non-destructive testing can monitor the structural health of hydrogen storage wells, promptly identify and address potential defects such as cracks and corrosion, thereby preventing hydrogen leaks and ensuring hydrogen storage safety.

[0007] Traditional non-destructive testing of hydrogen storage wells requires entering the well to perform the operation. However, in-well testing is limited by space and testing equipment, which may prevent the rapid and comprehensive coverage of all areas that need to be tested, thus affecting testing efficiency.

[0008] Meanwhile, in order to prevent high-concentration hydrogen from leaking or causing accidents that could threaten the lives of testing personnel, the hydrogen in the well needs to be released before testing can begin. Testing can only be carried out when the residual hydrogen concentration in the well is within a safe range. This not only increases the complexity and difficulty of the operation, but also makes it difficult to conduct testing at any time.

[0009] Therefore, how to more conveniently assess the integrity, reliability, and performance status of hydrogen storage wells, promptly identify potential defects in hydrogen storage wells, improve the reliability and stability of detection, and at the same time reduce the operational difficulty of detection, thereby greatly saving time and manpower costs, has become a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0010] In view of the above-mentioned deficiencies of the prior art, the present invention provides a combined circumferential and vertical non-destructive testing device and method for hydrogen storage wells. The purpose is to more conveniently evaluate the integrity, reliability and performance status of hydrogen storage wells, promptly detect potential defects in hydrogen storage wells, improve the reliability and stability of testing, and at the same time reduce the operational difficulty of testing, greatly saving time and labor costs.

[0011] To achieve the above objectives, the present invention discloses a combined circumferential and vertical non-destructive testing device for hydrogen storage wells, including a tubular outer wall retaining wall installed outside the well casing located underground and extending along the length of the well casing;

[0012] An external detection space is formed between the outer wall retaining wall and the well shaft;

[0013] Non-destructive testing technology is used to detect defects and damage to the wellbore in the external detection space, and digital means are combined to realize remote operation and data transmission.

[0014] Preferably, the non-destructive testing technology is ultrasonic non-destructive testing.

[0015] More preferably, the ultrasonic non-destructive testing includes an ultrasonic probe and an adjustment device for adjusting the position of the ultrasonic probe in the external testing space.

[0016] The adjustment device includes a circumferential track, a circumferential sliding support, an extension device, and a circumferential magnetic control device;

[0017] The circumferential track is set on the ground outside the opening at the upper end of the well shaft, coaxially arranged with the well shaft, and connected to the circumferential sliding support as a sliding pair;

[0018] The circumferential sliding bracket and the circumferential track are provided with multiple pulleys to form the moving pair, and the extension device and the circumferential magnetic control device are set by a fixed bracket;

[0019] The extension device suspends the ultrasonic probe via a self-controlled cable, enabling the ultrasonic probe to reciprocate vertically relative to the extension device.

[0020] The circumferential magnetic control device controls the circumferential sliding support to move along the circumferential track;

[0021] The other end of the self-controlled cable is coiled on a cable shaft located outside the well shaft, and the length of the portion entering the well shaft is collected by a rotation sensor.

[0022] More preferably, the ultrasonic probe is equipped with a CCTV device;

[0023] A digital control display screen is installed outside the well casing to display the working status of the adjustment device and the acquisition results of the ultrasonic probe.

[0024] More preferably, the ultrasonic nondestructive testing employs phased array ultrasonic testing technology, and the coupling method is liquid immersion.

[0025] More preferably, the water immersion thickness of the liquid immersion method The selection method for the coupling layer is as follows:

[0026] Step 1: Calculate the water immersion thickness. The specific formula is as follows:

[0027] ;

[0028] in, The probe chip diameter is in mm. The wavelength of the ultrasonic wave is in millimeters (mm). The speed of longitudinal waves in water is 1483 m / s; The velocity of sound in the well wall is expressed in m / s. The thickness of the well wall in the direction of detection, in mm;

[0029] Step 2: Based on the water immersion thickness, conduct detection tests with different water layer thicknesses to analyze the echo situation under different water layer thicknesses and determine the optimal water layer thickness selection range.

[0030] Preferably, the bottom end cap at the bottom of the well casing is sealed to the well casing without leakage; the bottom end cap is sealed to the outer retaining wall with oil well cement;

[0031] A cementing device is provided at the wellhead position at the upper end of the wellbore;

[0032] The cementing device includes a horizontal plate and supports disposed on both sides of the horizontal plate for fixing the horizontal plate;

[0033] The horizontal plate has a hole near the middle that matches the wellhead, and the wellhead is reinforced by fitting through the hole onto the outside of the wellhead.

[0034] Preferably, the wellbore is formed using reinforced concrete to create a cementing clamp device.

[0035] This invention also provides a detection method, which uses the above-mentioned combined circumferential and vertical non-destructive testing device for hydrogen storage wells to inspect the wellbore. The specific steps are as follows:

[0036] Step 1: Fill the annular detection space with water using a centrifugal pump and pipes;

[0037] Step 2: Using CNC technology, program the pre-designed detection path, control the ultrasonic probe to start from a position flush with the wellhead of the well, and control the ultrasonic probe to rotate clockwise around the well through a magnetically controlled circumferential adjustment device. Excite the piezoelectric crystals with electrical signals to generate ultrasonic waves, and control the excitation time of each crystal to achieve focusing and scanning of the ultrasonic beam.

[0038] Step 3: After completing one clockwise rotation to focus and scan, move the ultrasonic probe downwards a certain distance using the self-control cable of the ultrasonic probe, and then rotate it counterclockwise to complete one counterclockwise rotation to focus and scan.

[0039] Step 4: Repeat steps 2 and 3 until the entire surface area of ​​the wellbore is focused and scanned.

[0040] Preferably, the ultrasonic probe moves at a uniform speed, and the distance between each focusing and scanning, as well as the distance of each downward movement, is less than the scanning width of the ultrasonic probe, so that there is at least 15% overlap between the sampling results obtained from every two adjacent focusing and scanning.

[0041] The beneficial effects of this invention are:

[0042] This invention sets up a ring-shaped detection space outside the underground hydrogen storage well, providing a stable detection environment for ultrasonic testing. This design not only facilitates the installation and maintenance of the testing equipment and improves the timeliness, reliability and stability of the testing, but also reduces the difficulty of the testing operation, greatly saving time and labor costs.

[0043] The following will further explain the concept, specific structure, and technical effects of the present invention in conjunction with the accompanying drawings, so as to fully understand the purpose, features, and effects of the present invention. Attached Figure Description

[0044] Figure 1 A longitudinal cross-sectional structural schematic diagram of an embodiment of the present invention is shown.

[0045] Figure 2 A schematic diagram of the adjusting device structure is shown in one embodiment of the present invention.

[0046] Figure 3 A schematic diagram of a cementing device structure is shown in one embodiment of the present invention.

[0047] The components include: 1. CNC display screen; 2. Cable spindle; 3. Rotation sensor; 4. Circumferential track; 5. Wellbore; 6. Outer wall retaining wall; 7. Ultrasonic probe; 8. Bottom end cap; 9. Oil well cement; 10. Drain / injection pipe; 11. Pulley; 12. Circumferential sliding support; 13. Centrifugal pump; 14. Cementing device; 15. Automatic control cable; 16. Wellhead; 17. Extension device; and 18. Circumferential magnetic control device. Detailed Implementation

[0048] Example

[0049] like Figures 1 to 3 As shown, the combined circumferential and vertical non-destructive testing device for hydrogen storage wells includes a tubular outer wall retaining wall 6 that extends along the length of the well 5 and is installed outside the well 5 located underground.

[0050] An external inspection space is formed between the outer retaining wall 6 and the well shaft 5;

[0051] Non-destructive testing technology is used to detect defects and damage in wellbore 5 in the external inspection space, and digital means are combined to realize remote operation and data transmission.

[0052] The present invention constructs a tubular outer wall retaining wall 6 outside the wellbore 5 of the hydrogen storage well. The tubular outer wall retaining wall 6 has certain rigidity, strength, stability and waterproof performance.

[0053] The outer retaining wall 6 and the well casing 5 form an external inspection space, which not only avoids the pressure caused by direct contact between the well casing 5 and the surrounding soil and groundwater, as well as corrosion caused by the surrounding soil, microorganisms, and saline water, thus reducing the impact of the surrounding environment, but also allows non-destructive testing to be carried out at any time outside the well casing 5 using the annular external inspection space. This avoids direct contact between the testing and the high-pressure, high-concentration hydrogen environment inside the hydrogen storage well, reducing the safety risks and operational difficulties of the testing.

[0054] Using non-destructive testing technologies, such as ultrasonic testing and X-ray testing, in the external testing space can quickly and accurately detect defects and damage to the wellbore 5 without damaging the hydrogen storage well structure. It can also be combined with digital means to realize remote operation and data transmission, which helps to take timely measures for repair and maintenance, and further improves testing efficiency.

[0055] The annular external detection space not only provides convenient conditions for the continuous detection of hydrogen storage wells, but also avoids the squeezing pressure caused by direct contact with the surrounding soil and groundwater during daily operation, as well as corrosion caused by the surrounding soil, microorganisms, and saline water, thereby reducing the impact of the surrounding environment and improving the service life of the hydrogen storage wells.

[0056] In some embodiments, the nondestructive testing technique is ultrasonic nondestructive testing.

[0057] In practical applications, ultrasonic nondestructive testing is the most frequently used and fastest-growing testing technology in the field of nondestructive testing, and it is widely used in industrial flaw detection.

[0058] In some embodiments, ultrasonic nondestructive testing includes an ultrasonic probe 7 and an adjustment device for adjusting the position of the ultrasonic probe 7 in the external testing space.

[0059] The adjustment device includes a circumferential track 4, a circumferential sliding bracket 12, an extension device 17, and a circumferential magnetic control device 18;

[0060] The circumferential track 4 is set on the ground outside the opening at the upper end of the well shaft 5, coaxial with the well shaft 5, and connected to the circumferential sliding support 12 as a sliding pair;

[0061] Multiple pulleys 11 are provided between the circumferential sliding bracket 12 and the circumferential track 4 to form a moving pair, and an extension device 17 and a circumferential magnetic control device 18 are provided through a fixed bracket;

[0062] The extension device 17 suspends the ultrasonic probe 7 via the self-controlled cable 15 to achieve vertical reciprocating movement of the ultrasonic probe 7 relative to the extension device 17.

[0063] The circumferential magnetic control device 18 controls the circumferential sliding support 12 to move along the circumferential track 4.

[0064] This invention utilizes an automatic control system based on the principle of electromagnetic induction to control an ultrasonic probe 7 to perform combined circumferential and vertical automatic detection of hydrogen storage wells outside the well, greatly improving detection efficiency and accuracy and ensuring no omissions in the detection.

[0065] During testing, an electromagnetic automatic control system controls the rotation of the cable shaft. A rotation sensor detects the number of rotations or angles of the cable as it passes through, automatically measuring parameters such as the cable's length and speed, and displaying them precisely on a CNC screen. This allows for the vertical positioning of the ultrasonic probe at the cable's end. A circumferential sliding support is installed at the wellhead, with pulleys at its bottom. The support slides along a pre-set circumferential track on the wellhead surface. An adjustable extension device is also installed on the support, on which the cable is laid. During testing, the length of the extension device can be adjusted as needed to control the horizontal distance between the ultrasonic probe and the hydrogen storage wellbore. During circumferential testing, the circumferential magnetic control device of the sliding support controls the pulleys to slide circumferentially, thereby driving the ultrasonic probe to complete the circumferential testing of the wellbore.

[0066] In some embodiments, the ultrasonic probe 7 is equipped with a CCTV device;

[0067] A digital control display screen 1 is installed outside the well shaft 5 to display the working status of the adjustment device and the acquisition results of the ultrasonic probe 7.

[0068] In practical applications, the ultrasonic probe 7 equipped with a CCTV device can display video images of the external inspection space in real time, allowing ground inspection personnel to clearly understand the structure and condition of the wellbore 5, which facilitates subsequent pipeline maintenance, repair and modification work.

[0069] In some embodiments, ultrasonic nondestructive testing employs phased array ultrasonic testing technology, with the coupling method being liquid immersion.

[0070] From the perspective of the coupling method between the ultrasonic probe 7 and the workpiece, ultrasonic non-destructive testing can be divided into two main categories: contact method and liquid immersion method. Among them, the liquid immersion method has higher resolution, sensitivity and reliability.

[0071] In some embodiments, the water immersion thickness of the liquid immersion method The selection method for the coupling layer is as follows:

[0072] Step 1: Calculate the water immersion thickness The specific formula is as follows:

[0073] ;

[0074] in, The probe chip diameter is in mm. The wavelength of the ultrasonic wave is in millimeters (mm). The speed of longitudinal waves in water is 1483 m / s; The velocity of sound in the well wall is expressed in m / s. The thickness of the well wall in the direction of detection, in mm;

[0075] Step 2: Based on the water immersion thickness, conduct detection tests with different water layer thicknesses to analyze the echo situation under different water layer thicknesses and determine the optimal water layer thickness selection range.

[0076] In some embodiments, the bottom end cap 8 at the bottom of the wellbore 5 is sealed to the wellbore 5 without leakage; the bottom end cap 8 and the outer wall retaining wall 6 are sealed with oil well cement 9.

[0077] A cementing device 14 is provided at the wellhead 16 position at the upper end of the wellbore 5;

[0078] The cementing device 14 includes a horizontal plate and supports disposed on both sides of the horizontal plate for fixing the horizontal plate;

[0079] The horizontal plate has a hole near the middle that matches the wellhead 16. The wellhead 16 is reinforced by fitting through the hole to the outside of the wellhead 16.

[0080] If necessary, anchors such as anchor bolts or anchor cables can be installed at the bottom of the wellbore 5. These anchors can penetrate deep into the underground rock or soil layers to provide additional fixation and support. Through the solidification of the well cement, the anchors can be firmly bonded to the casing and formation to form a stable integral structure.

[0081] In practical applications, the above-mentioned technical means can ensure the stability of the wellbore 5 of the hydrogen storage well.

[0082] In some embodiments, the wellbore 5 is formed with reinforced concrete to create a cementing clamp device.

[0083] In practical applications, the cementing clamp device outside the wellbore 5 ensures the vertical fixation of the wellbore 5 of the hydrogen storage well.

[0084] This invention also provides a detection method, which uses the above-mentioned combined circumferential and vertical non-destructive testing device for hydrogen storage wells to test the wellbore 5. The specific steps are as follows:

[0085] Step 1: Fill the annular detection space with water using centrifugal pump 13 and drain / injection pipe 10;

[0086] Step 2: Using CNC technology, program the detection path and control the ultrasonic probe 7 to start from a position flush with the wellhead of the well 5. Control the ultrasonic probe 7 to rotate clockwise around the well 5 through the circumferential sliding bracket 12. Excite the piezoelectric crystal to generate ultrasonic waves through electrical signals and control the excitation time of each crystal to achieve focusing and scanning of the ultrasonic beam.

[0087] Step 3: After completing the focusing and scanning by rotating clockwise one full circle, move the ultrasonic probe 7 downward a certain distance through the self-control cable 15 of the ultrasonic probe 7, and then rotate counterclockwise one full circle to complete the focusing and scanning.

[0088] Step 4: Repeat steps 2 and 3 until the entire surface area of ​​wellbore 5 is focused and scanned.

[0089] In some embodiments, the ultrasonic probe 7 moves at a uniform speed, and the distance of movement between each focusing and scanning, as well as the distance of downward movement each time, is less than the scanning width of the ultrasonic probe 7, so that there is at least 15% overlap between the sampling results obtained from every two adjacent focusing and scanning.

[0090] In practical applications, the above-mentioned technical means can ensure 100% detection in a combination of circumferential and vertical directions during the scanning process.

[0091] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A method for detecting hydrogen storage wells; characterized in that, The wellbore (5) was inspected using a combined circumferential and vertical non-destructive testing device. The combined circumferential and vertical non-destructive testing device for the hydrogen storage well includes a tubular outer wall retaining wall (6) that is installed outside the well casing (5) located underground and extends along the length of the well casing (5). An external detection space is formed between the outer wall retaining wall (6) and the well shaft (5); Non-destructive testing technology is used to detect defects and damage in the wellbore (5) in the external detection space, and remote operation and data transmission are achieved by combining digital means. The non-destructive testing technology mentioned is ultrasonic non-destructive testing; The ultrasonic non-destructive testing includes an ultrasonic probe (7) and an adjustment device for adjusting the position of the ultrasonic probe (7) in the external testing space. The adjustment device includes a circumferential track (4), a circumferential sliding bracket (12), an extension device (17), and a circumferential magnetic control device (18). The circumferential track (4) is set on the ground outside the upper opening of the well shaft (5), coaxially with the well shaft (5), and connected to the circumferential sliding support (12) as a sliding pair; The circumferential sliding bracket (12) and the circumferential track (4) are provided with multiple pulleys (11) to form the moving pair, and the extension device (17) and the circumferential magnetic control device (18) are set by a fixed bracket. The extension device (17) suspends the ultrasonic probe (7) via a self-controlled cable (15) to enable the ultrasonic probe (7) to move vertically back and forth relative to the extension device (17). The circumferential magnetic control device (18) controls the circumferential sliding support (12) to move along the circumferential track (4); The other end of the self-controlled cable (15) is coiled on the cable shaft (2) located outside the well shaft (5), and the length of the part entering the well shaft (5) is collected by the rotation sensor (3); The ultrasonic probe (7) is equipped with a CCTV device; The wellbore (5) is equipped with a digital control display screen (1) to display the working status of the adjustment device and the acquisition results of the ultrasonic probe (7); The ultrasonic non-destructive testing employs phased array ultrasonic testing technology, with liquid immersion coupling method. The water immersion thickness of the liquid immersion method The selection method for the coupling layer is as follows: Step 1: Calculate the water immersion thickness. The specific formula is as follows: ； in, The probe chip diameter is in mm. The wavelength of the ultrasonic wave is in millimeters (mm). The speed of longitudinal waves in water is 1483 m / s; The velocity of sound in the well wall is expressed in m / s. The thickness of the well wall in the direction of detection, in mm; Step 2: Based on the water immersion thickness, conduct detection tests with different water layer thicknesses to analyze the echo situation under different water layer thicknesses and determine the optimal water layer thickness selection range. The steps for inspecting the wellbore (5) are as follows: Step 1: Fill the annular detection space with water using a centrifugal pump (13) and a drain / injection pipe (10); Step 2: Using CNC technology, program the detection path and control the ultrasonic probe (7) to start from the position flush with the wellhead of the well (5). Control the ultrasonic probe (7) to rotate clockwise around the well (5) through the circumferential sliding bracket (12). Excite the piezoelectric crystal to generate ultrasonic waves through electrical signals and control the excitation time of each crystal to achieve focusing and scanning of the ultrasonic beam. Step 3: After completing the focusing and scanning by rotating clockwise around the circumference once, move the ultrasonic probe (7) downward a certain distance through the self-control cable (15) of the ultrasonic probe (7), and then rotate counterclockwise around the circumference once to complete the focusing and scanning. Step 4: Repeat steps 2 and 3 until the entire surface area of ​​the wellbore (5) is focused and scanned; The distance of movement between each focusing and scanning, as well as the distance of downward movement each time, are less than the scanning width of the ultrasonic probe (7), so that there is at least 15% overlap between the sampling results obtained from each two adjacent focusing and scanning.

2. The detection method for hydrogen storage wells according to claim 1, characterized in that, The bottom end cap (8) at the bottom of the well shaft (5) is sealed to the well shaft (5) without leakage; the bottom end cap (8) and the outer wall retaining wall (6) are sealed with oil well cement (9); A cementing device (14) is provided at the wellhead (16) at the upper end of the wellbore (5). The cementing device (14) includes a horizontal plate and supports disposed on both sides of the horizontal plate for fixing the horizontal plate; The horizontal plate has a hole near the middle that matches the wellhead (16), and the wellhead (16) is reinforced by being fitted through the hole to the outside of the wellhead (16).

3. The detection method for hydrogen storage wells according to claim 1, characterized in that, The wellbore (5) is formed by using reinforced concrete to form a cementing clamp device.

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