A well abandonment casing cement sheath fracturing test device and method

Abstract

A kind of well abandonment casing cement sheath crushing test device and method, including test table, axial movement system, rotating system, cement sheath crusher, clamping system, hydraulic loading system, cement sheath filling system, the movement and working condition of cement sheath crusher are controlled by axial movement system, rotating system, hydraulic loading system to realize the extrusion crushing of cement sheath;The working parameters when crushing cement sheath are adjusted by changing the high-pressure liquid output to axial movement system, rotating system, cement sheath crusher by hydraulic loading system, the overall structure is simple, easy to process manufacture assembly, can measure the working pressure and torque of cement sheath crusher, test the operating performance of cement sheath crusher, more complete simulation cement sheath crusher specific working condition when downhole operation, the optimization improvement of tool and the improvement of the whole casing recovery operation mode have positive reference significance and popularization value.

Description

Technical Field

[0001] This invention relates to a simulation experimental device for the recovery of abandoned well casing in the petroleum industry, and in particular to a test device and method for the crushing of cement sheath in abandoned well casing. Background Technology

[0002] With the continuous exploitation of oil fields, most are now in the late stages of exploitation, and a large number of oil and gas wells have been permanently abandoned. To avoid environmental pollution and ecological damage caused by residual oil and gas leaks, it is necessary to isolate the oil and gas. Permanent well abandonment operations should be carried out in accordance with industry requirements. Well abandonment operations require selecting an appropriate well depth to cut and retrieve the casing, and then permanently seal it with cement. After the cementing operation is completed, the inner casing, cement sheath, outer casing and formation are bonded together due to the solidification of cement slurry. This greatly increases the resistance to pulling out the casing, making it difficult or even impossible to pull out the casing from the wellbore. Cutting a small section of casing first and then pulling it out step by step will increase the well abandonment operation cycle and cost. In short, the traditional well abandonment operation casing recovery method can no longer meet the market demand for well abandonment operations. Now, for the first time in China, a tool with piston extrusion and rotation operation is used to reduce the bonding strength between the casing and cement sheath and improve the efficiency of casing recovery operations.

[0003] Traditional testing equipment cannot meet the indoor testing requirements of this type of tool, making it difficult to measure its thrust and torque during actual operation. To measure the actual operating performance of this type of tool, actual well casing recovery operations are required, but the safety of such operations is difficult to guarantee, and it is also easy to cause resource waste and environmental pollution. Summary of the Invention

[0004] To address the above problems, this invention proposes a test device and method for the crushing of cement sheaths in abandoned well casings, aiming to solve the indoor performance testing requirements of cement sheath crushers and provide new solutions and ideas for abandoned well casing recovery operations in the domestic petroleum industry.

[0005] This invention is achieved through the following technical solution:

[0006] A test apparatus and method for crushing cement sheaths in abandoned well casings, characterized in that it includes a test bench, an axial movement system, a rotation system, a cement sheath crushing system, a hydraulic loading system 27, and a cement sheath filling system; wherein, the movement of the cement sheath crusher is controlled by the axial movement system, the rotation system, and the hydraulic loading system 27 to achieve the crushing of the cement sheath 21 by compression; the working parameters for crushing the cement sheath are adjusted by changing the high-pressure liquid input to the axial movement system, the rotation system, and the cement sheath crusher through the hydraulic loading system 27.

[0007] The axial movement system consists of an axial hydraulic cylinder 3, a slide block 6, a fixing bolt 17, a splined shaft 7, and a coupling 9. A limit hole is provided on the test bench to facilitate the movement and fixation of the axial hydraulic cylinder 3. Limiting is achieved by screws. The slide block 6 is fixedly connected to the extended portion of the piston rod 5. High-pressure liquid is injected into the axial hydraulic cylinder 3 through the hydraulic loading system 27, causing the piston rod 5 to move axially. The piston rod 5 drives the slide block to move axially, and the slide block 6 transmits the axial force to the splined shaft 7. The cement ring crusher 10 is connected to the splined shaft 7 via the coupling 9, thereby controlling the axial movement of the cement ring crusher 10.

[0008] The rotating system consists of a slide block 6, a splined shaft 7, a hydraulic motor 18, a rotating wheel 8, and a coupling 9. The hydraulic motor 18 is pressurized by the hydraulic loading system 27, and the hydraulic motor 18 rotates to drive the rotating wheel 8. The rotating wheel 8 drives the splined shaft 7 to rotate by meshing with the external spline of the splined shaft 7. The torque is then transmitted to the cement ring crusher 10 through the coupling 9, which drives the cement ring crusher 10 to rotate in the working state.

[0009] The cement ring crushing system consists of a left-end test connecting shaft 19, a cement ring crusher 10, an outer sleeve 22, a cement ring 21, an inner sleeve 20, a right-end test connecting shaft 13, and a rotary joint 23. The hydraulic loading system 27 is connected to the rotary joint 23 via a hydraulic pipeline 24, so that the pipeline does not rotate with the cement ring crusher 10 when transmitting high-pressure liquid. By pressurizing the cement ring crusher 10, the piston in the middle moving roller is pushed out. Under the action of the piston's lateral force, the tool generates eccentric movement, applying extrusion force to the inner sleeve, causing the sleeve to undergo elastic deformation, thereby crushing the cement ring 21.

[0010] The cement ring filling system consists of a filling support 28, a limiting support 29, an inner sleeve 20, and an outer sleeve 22. The filling support 28 keeps the outer sleeve 22 stable, the limiting support 29 adjusts the position of the inner sleeve 20, and the lowest end of the outer sleeve 22 is equipped with a cement filling blocking plate 30, which can both seal the cement slurry and make the inner and outer sleeves concentric.

[0011] The method used in the laboratory test of cement ring crushing using this experimental apparatus includes the following steps:

[0012] Step 1: No-load start-up load calibration test of the test system. In order to facilitate the verification and processing of subsequent test data, the initial parameters of the test bench need to be calibrated. For the no-load test bench without tools, calibrate the data of the axial hydraulic cylinder 3 pushing friction and spline shaft 7 friction.

[0013] Step 2: After the cement ring is formed by filling the cement slurry into the cement ring filling system according to the standard, the sleeve cement ring assembly and the cement ring crusher 10 are assembled onto the test device. After the device is connected, the cement ring crusher 10 is emptied and the entire system is checked to see if it is normal. The main checks are whether the sleeve clamping is reliable, whether the tool is connected firmly, whether the tail end of the cement ring crusher 10 is tightly sealed, and whether the connection between the hydraulic loading system 27 and the tool is normal.

[0014] Step 3: Activate the axial hydraulic cylinder 3 to move the splined shaft 7 onto the shaft so that the outer spline engages with the inner spline of the rotating wheel 8. Then, activate the hydraulic motor 18 and start the hydraulic loading system 27 to inject hydraulic oil into the cement ring crusher 10.

[0015] Step 4: Slowly adjust the hydraulic oil pressure injected into the hydraulic loading system 27 until it reaches the piston starting pressure of the cement ring crusher 10. Record the pressure and speed of the oil inlet and outlet of the hydraulic motor 18, and then calculate the actual working torque of the hydraulic motor (18). Record the axial hydraulic cylinder pressure difference to calculate the axial thrust on the tool. Observe and record the cement ring damage and the sleeve bending condition.

[0016] Step 5: The hydraulic loading system 27 injects pressure into the cement ring crusher 10 at each pressure level, and records the values ​​at each pressure level.

[0017] Step 6: Remove the cement ring crusher 10 and the crushed casing cement ring assembly, clean and tidy the entire test device, and move the crushed casing cement ring assembly to other test devices to conduct casing pull-out force tests to further verify the cement ring crushing effect.

[0018] In summary, the present invention has the following benefits:

[0019] This invention proposes a test device and method for cement sheath breakage in abandoned well casing. The device has a simple structure, is easy to manufacture and assemble, and can measure the working pressure of the cement sheath breaker in real time when the cement sheath breaks, thus determining the required thrust and torque for breaking the cement sheath. It tests the operational performance of the cement sheath breaker and can relatively completely simulate the specific working conditions of the cement sheath breaker during downhole operations. This invention fills a domestic gap and has positive reference value and promotional value for the optimization and improvement of cement sheath breakers and the improvement of the entire casing recovery operation mode. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of a cement ring crushing experiment provided in an embodiment of the present invention;

[0022] Figure 2 This is a schematic diagram of a cement filling experiment provided in an embodiment of the present invention;

[0023] 1. Test bench; 2. Support frame a; 3. Axial hydraulic cylinder; 4. Support frame b; 5. Piston rod; 6. Slide block; 7. Splined shaft; 8. Rotary wheel; 9. Coupling; 10. Cement ring crusher; 11. Clamping device a; 12. Clamping device b; 13. Right end test connecting shaft; 14. Hydraulic line a; 15. Hydraulic line b; 16. Roller; 17. Fixing bolt; 18. Hydraulic motor; 19. Left end test connecting shaft; 20. Inner sleeve; 21. Cement ring; 22. Outer sleeve; 23. Rotary joint; 24. Hydraulic line c; 25. Hydraulic line d; 26. Hydraulic line e; 27. Hydraulic loading system; 28. Filling bracket; 29. ​​Limiting bracket; 30. Cement filling stopper. Detailed Implementation

[0024] The present invention will be further described below with reference to the accompanying drawings. The scope of protection of the present invention includes, but is not limited to, the following description.

[0025] Example 1

[0026] In this embodiment, the maximum injection pressure of the cement ring crusher is 25 MPa, and the rotation speed is 30 r / min.

[0027] A test apparatus and method for testing the fracture of cement sheath in abandoned well casing, such as Figure 1 As shown, the system includes a test bench, an axial movement system, a rotation system, a cement ring crusher 10, a clamping system, a hydraulic loading system 27, and a cement ring filling system. The axial movement system, rotation system, and hydraulic loading system control the movement and working state of the cement ring crusher to achieve the crushing of the cement ring. The hydraulic loading system 27 adjusts the working parameters when crushing the cement ring by changing the high-pressure liquid input to the axial movement system, rotation system, and cement ring crusher 10.

[0028] The axial movement system consists of an axial hydraulic cylinder 3, a slide block 6, a fixing bolt 17, a splined shaft 7, a coupling 9, a support frame a2, and a support frame b4. The slide block 6 is fixedly connected to the extended part of the piston rod 5. High-pressure liquid is injected into the axial hydraulic cylinder 3 through the hydraulic loading system 27 to push out the piston rod 5. The piston rod 5 drives the slide block 6 to move axially. The slide block 6 transmits the axial force to the splined shaft 7. The cement ring crusher 10 is connected to the splined shaft 7 through the coupling 9, thereby controlling the axial movement of the cement ring crusher.

[0029] The splined shaft 7 is a stepped cylinder with varying diameters at both ends. The two ends are connected to the slide block 6 and the coupling 9, respectively, and mesh with the rotating wheel 8. It is the main component in the entire test system that transmits axial force and torque.

[0030] The rotating system consists of a slide block 6, a splined shaft 7, a hydraulic motor 18, a rotating wheel 8, and a coupling 9. The hydraulic motor 18 is pressurized by the hydraulic loading system 27, which drives the rotating wheel 8. The rotating wheel 8 rotates the splined shaft 7 by meshing with the external spline of the splined shaft 7. The torque is then transmitted to the cement ring crusher 10 through the coupling 9, which drives the cement ring crusher 10 to rotate in the working state.

[0031] The cement ring crushing system consists of a left-end test connecting shaft 19, a cement ring crusher 10, an outer sleeve 22, a cement ring 21, an inner sleeve 20, a right-end test connecting shaft 13, and a rotary joint 23. The hydraulic loading system 27 is connected to the rotary joint 23 via a hydraulic pipeline c24, so that the pipeline does not rotate with the cement ring crusher 10 when transmitting high-pressure liquid. By pressurizing the cement ring crusher 10, the piston in the middle moving roller is pushed out. Under the action of the piston's lateral force, the tool generates eccentric movement, applying extrusion force to the inner sleeve 20, causing the inner sleeve 20 to undergo elastic deformation, thereby crushing the cement ring 21.

[0032] The cement ring filling system consists of a filling bracket 28, a limiting bracket 29, an inner sleeve 20, and an outer sleeve 22. The filling bracket 28 keeps the inner sleeve 20 stable, the limiting bracket 29 adjusts the position of the outer sleeve 22, and the lowest end of the outer sleeve is equipped with a cement filling plug 30, which can both seal the cement slurry and make the inner and outer sleeves concentric.

[0033] The method used in the laboratory test of cement ring crushing using this experimental apparatus includes the following steps:

[0034] Step 1: No-load start-up load calibration test of the test system. In order to facilitate the verification and processing of subsequent test data, the initial parameters of the test bench need to be calibrated. For the no-load test bench without tools, calibrate the data of the axial hydraulic cylinder 3 pushing friction and spline shaft 7 friction.

[0035] Step 2: After the cement ring is formed by filling the cement slurry into the cement ring filling system according to the standard, the sleeve cement ring assembly and the cement ring crusher 10 are assembled onto the test device. After the device is connected, the cement ring crusher 10 is emptied and the entire system is checked to see if it is normal. The main checks are whether the sleeve clamping is reliable, whether the tool is connected firmly, whether the tail end of the cement ring crusher 10 is tightly sealed, and whether the connection between the hydraulic loading system 27 and the tool is normal.

[0036] Step 3: Activate the axial hydraulic cylinder 3 to move the splined shaft 7 onto the shaft so that the outer spline engages with the inner spline of the rotating wheel 8. Then, activate the hydraulic motor 18 and start the hydraulic loading system 27 to inject hydraulic oil into the cement ring crusher 10.

[0037] Step 4: Slowly adjust the hydraulic oil pressure injected into the hydraulic loading system 27 until it reaches the piston starting pressure of the cement ring crusher 10. Record the pressure and speed of the oil inlet and outlet of the hydraulic motor 18, and then calculate the actual working torque of the hydraulic motor (18). Record the axial hydraulic cylinder pressure difference to calculate the axial thrust on the tool. Observe and record the cement ring damage and the sleeve bending condition.

[0038] Step 5: The hydraulic loading system 27 injects pressure into the cement ring crusher 10 at each pressure level, and records the values ​​at each pressure level.

[0039] Step 6: Remove the cement ring crusher 10 and the crushed casing cement ring assembly, clean and tidy the entire test device, and move the crushed casing cement ring assembly to other test devices to conduct casing pull-out force tests to further verify the cement ring crushing effect.

[0040] Example 2

[0041] In this embodiment, the maximum injection pressure of the cement ring crusher is 35 MPa, and the rotation speed is 30 r / min.

[0042] A test apparatus and method for testing the fracture of cement sheath in abandoned well casing, such as Figure 1 As shown, the system includes a test bench, an axial movement system, a rotation system, a cement ring crusher 10, a clamping system, a hydraulic loading system 27, and a cement ring filling system. The axial movement system, rotation system, and hydraulic loading system control the movement and working state of the cement ring crusher to achieve the crushing of the cement ring. The hydraulic loading system 27 adjusts the working parameters when crushing the cement ring by changing the high-pressure liquid input to the axial movement system, rotation system, and cement ring crusher 10.

[0043] The axial movement system consists of an axial hydraulic cylinder 3, a slide block 6, a fixing bolt 17, a splined shaft 7, a coupling 9, a support frame a2, and a support frame b4. The slide block 6 is fixedly connected to the extended part of the piston rod 5. High-pressure liquid is injected into the axial hydraulic cylinder 3 through the hydraulic loading system 27 to push out the piston rod 5. The piston rod 5 drives the slide block 6 to move axially. The slide block 6 transmits the axial force to the splined shaft 7. The cement ring crusher 10 is connected to the splined shaft 7 through the coupling 9, thereby controlling the axial movement of the cement ring crusher.

[0044] The splined shaft 7 is a stepped cylinder with varying diameters at both ends. The two ends are connected to the slide block 6 and the coupling 9, respectively, and mesh with the rotating wheel 8. It is the main component in the entire test system that transmits axial force and torque.

[0045] The rotating system consists of a slide block 6, a splined shaft 7, a hydraulic motor 18, a rotating wheel 8, and a coupling 9. The hydraulic motor 18 is pressurized by the hydraulic loading system 27, which drives the rotating wheel 8. The rotating wheel 8 rotates the splined shaft 7 by meshing with the external spline of the splined shaft 7. The torque is then transmitted to the cement ring crusher 10 through the coupling 9, which drives the cement ring crusher 10 to rotate in the working state.

[0046] The cement ring crushing system consists of a left-end test connecting shaft 19, a cement ring crusher 10, an outer sleeve 22, a cement ring 21, an inner sleeve 20, a right-end test connecting shaft 13, and a rotary joint 23. The hydraulic loading system 27 is connected to the rotary joint 23 via a hydraulic pipeline c24, so that the pipeline does not rotate with the cement ring crusher 10 when transmitting high-pressure liquid. By pressurizing the cement ring crusher 10, the piston in the middle moving roller is pushed out. Under the action of the piston's lateral force, the tool generates eccentric movement, applying extrusion force to the inner sleeve 20, causing the inner sleeve 20 to undergo elastic deformation, thereby crushing the cement ring 21.

[0047] The cement ring filling system consists of a filling bracket 28, a limiting bracket 29, an inner sleeve 20, and an outer sleeve 22. The filling bracket 28 keeps the inner sleeve 20 stable, the limiting bracket 29 adjusts the position of the outer sleeve 22, and the lowest end of the outer sleeve is equipped with a cement filling plug 30, which can both seal the cement slurry and make the inner and outer sleeves concentric.

[0048] The method used in the laboratory test of cement ring crushing using this experimental apparatus includes the following steps:

[0049] Step 1: No-load start-up load calibration test of the test system. In order to facilitate the verification and processing of subsequent test data, the initial parameters of the test bench need to be calibrated. For the no-load test bench without tools, calibrate the data of the axial hydraulic cylinder 3 pushing friction and spline shaft 7 friction.

[0050] Step 2: After the cement ring is formed by filling the cement slurry into the cement ring filling system according to the standard, the sleeve cement ring assembly and the cement ring crusher 10 are assembled onto the test device. After the device is connected, the cement ring crusher 10 is emptied and the entire system is checked to see if it is normal. The main checks are whether the sleeve clamping is reliable, whether the tool is connected firmly, whether the tail end of the cement ring crusher 10 is tightly sealed, and whether the connection between the hydraulic loading system 27 and the tool is normal.

[0051] Step 3: Activate the axial hydraulic cylinder 3 to move the splined shaft 7 onto the shaft so that the outer spline engages with the inner spline of the rotating wheel 8. Then, activate the hydraulic motor 18 and start the hydraulic loading system 27 to inject hydraulic oil into the cement ring crusher 10.

[0052] Step 4: Slowly adjust the hydraulic oil pressure injected into the hydraulic loading system 27 until it reaches the piston starting pressure of the cement ring crusher 10. Record the pressure and speed of the oil inlet and outlet of the hydraulic motor 18, and then calculate the actual working torque of the hydraulic motor (18). Record the axial hydraulic cylinder pressure difference to calculate the axial thrust on the tool. Observe and record the cement ring damage and the sleeve bending condition.

[0053] Step 5: The hydraulic loading system 27 injects pressure into the cement ring crusher 10 at each pressure level, and records the values ​​at each pressure level.

[0054] Step 6: Remove the cement ring crusher 10 and the crushed casing cement ring assembly, clean and tidy the entire test device, and move the crushed casing cement ring assembly to other test devices to conduct casing pull-out force tests to further verify the cement ring crushing effect.

[0055] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A test device for the crushing of cement sheath in abandoned well casing, characterized in that: It includes a test bench, an axial movement system, a rotation system, a cement ring crushing system, a hydraulic loading system (27), and a cement ring filling system; wherein, the movement of the cement ring crusher is controlled by the axial movement system, the rotation system, and the hydraulic loading system (27) to achieve the crushing of the cement ring (21); the working parameters when crushing the cement ring are adjusted by changing the high pressure liquid input to the axial movement system, the rotation system, and the cement ring crusher through the hydraulic loading system (27); The axial movement system consists of an axial hydraulic cylinder (3), a slide (6), a fixing bolt (17), a splined shaft (7), and a coupling (9). There are limit holes on the test bench to facilitate the movement and fixation of the axial hydraulic cylinder (3). The limit is set by screws. The slide (6) is fixedly connected to the extended part of the piston rod (5). The hydraulic loading system (27) injects high pressure liquid into the axial hydraulic cylinder (3) to push out the piston rod (5). The piston rod (5) drives the slide to move axially. The slide (6) transmits the axial force to the splined shaft (7). The cement ring crusher (10) is connected to the splined shaft (7) through the coupling (9) to control the axial movement of the cement ring crusher (10). The rotating system consists of a slide (6), a splined shaft (7), a hydraulic motor (18), a rotating wheel (8), and a coupling (9). The hydraulic motor (18) is pressurized by the hydraulic loading system (27), and the hydraulic motor (18) rotates to drive the rotating wheel (8). The rotating wheel (8) drives the splined shaft (7) to rotate by meshing with the external spline of the splined shaft (7). The torque is then transmitted to the cement ring crusher (10) through the coupling (9), which drives the cement ring crusher (10) to rotate in the working state.

2. The well casing cement sheath fracture test device according to claim 1, characterized in that: The cement ring crushing system consists of a left-end test connecting shaft (19), a cement ring crusher (10), an outer sleeve (22), a cement ring (21), an inner sleeve (20), a right-end test connecting shaft (13), and a rotary joint (23). The hydraulic loading system (27) is connected to the rotary joint (23) through a hydraulic pipeline (24), so that the pipeline does not rotate with the cement ring crusher (10) when transmitting high-pressure liquid. By pressurizing the cement ring crusher (10), the piston in the middle moving roller part is pushed out. Under the action of the piston's lateral force, the tool generates eccentric movement, applies extrusion force to the inner sleeve, and causes the sleeve to undergo elastic deformation, thereby crushing the cement ring (21).

3. The well casing cement sheath crushing test device according to claim 1, characterized in that: The cement ring filling system consists of a filling bracket (28), a limiting bracket (29), an inner sleeve (20), and an outer sleeve (22). The filling bracket (28) keeps the outer sleeve (22) stable, the limiting bracket (29) adjusts the position of the inner sleeve (20), and the bottom of the outer sleeve (22) is equipped with a cement filling plug (30), which can both seal the cement slurry and make the inner and outer sleeves concentric.

4. A method for testing the fracture of cement sheath in abandoned well casing, characterized in that: The indoor test for cement ring crushing using the test apparatus according to any one of claims 1-3 includes the following steps: Step 1: No-load start-up load calibration test of the test system. In order to facilitate the verification and processing of subsequent test data, the initial parameters of the test bench need to be calibrated. For the no-load test bench without tools, calibrate the friction data of the axial hydraulic cylinder (3) push and the spline shaft (7). Step 2: After the cement ring is formed by filling the cement slurry on the cement ring filling system according to the standard, the sleeve cement ring assembly and the cement ring crusher (10) are assembled onto the test device. After the device is connected, the cement ring crusher (10) is emptied and then the whole system is checked to see if it is normal. The main checks are whether the sleeve clamping is reliable, whether the tool is connected firmly, whether the tail end of the cement ring crusher (10) is tightly sealed, and whether the connection between the hydraulic loading system (27) and the tool is normal. Step 3: Turn on the axial hydraulic cylinder (3) to move the spline shaft (7) to the shaft and engage the outer spline with the inner spline of the rotating wheel (8). Then turn on the hydraulic motor (18) and start the hydraulic loading system (27) to inject hydraulic oil into the cement ring crusher (10). Step 4: Slowly adjust the hydraulic oil pressure injected into the hydraulic loading system (27) until it reaches the piston starting pressure of the cement ring crusher (10). Record the pressure and speed of the inlet and outlet of the hydraulic motor (18) and then calculate the actual working torque of the hydraulic motor (18). Record the pressure difference of the axial hydraulic cylinder (3) to calculate the axial thrust on the tool. Observe and record the cement ring damage and the sleeve bending condition. Step 5: The hydraulic loading system (27) injects pressure into the cement ring crusher (10) step by step, and records the values ​​at each pressure level; Step 6: Remove the cement ring crusher (10) and the crushed casing cement ring assembly, clean and tidy the entire test device, and move the crushed casing cement ring assembly to other test devices to conduct casing pull-out force test to further verify the cement ring crushing effect.

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