Anti-eccentric-wearing iterative optimization method and system based on sucker rod string dynamics analysis

Abstract

The present application belongs to the field of sucker rod pumping design in oil exploitation, and discloses an anti-eccentric wear iterative optimization method and system based on the dynamics analysis of the sucker rod string, which comprises the following steps: establishing a wellbore trajectory model of a space rectangular coordinate system; calculating the position of the neutral point when the rod string is descending; based on the position of the neutral point when the rod string is descending, combining the wear amount of the corresponding centralizer, describing the lateral force size of any point in the descending process of the sucker rod string, and the installation density of the centralizer at the target depth; combining the centralizer density and the real eccentric wear situation of the historical rod string at different depths of a single well with the centralizer installation density calculation difference at the target depth, iteratively predicting until the calculation result is consistent with the actual eccentric wear situation, and completing the optimization. The technical scheme of the present application significantly improves the accuracy and practicality of the anti-eccentric wear design of the sucker rod string through the iterative optimization method. It not only simplifies the design process and improves the work efficiency, but also achieves remarkable field application effect.

Description

Technical Field

[0001] This invention belongs to the field of rod pump oil production design in oil extraction, specifically involving an anti-wear iterative optimization method and system based on the dynamic analysis of the sucker rod string. Background Technology

[0002] Installing centralizers on the sucker rod string is a primary method for preventing eccentric wear. Currently, the design of eccentric wear prevention for sucker rod strings in various oilfields mainly relies on experience. The few existing eccentric wear prediction models only consider the stress conditions of the rod string before the centralizer is installed under current production conditions. They do not incorporate research on the wear resistance of the centralizer to determine how to best extend the rod string life by installing it at the predicted eccentric wear points, nor do they provide iterative optimization of existing theoretical prediction models and corresponding eccentric wear prevention design schemes based on the actual historical eccentric wear conditions of the well's sucker rod string. In practice, when using these prediction models for eccentric wear prevention design, it is often found that after densely installing centralizers at the predicted eccentric wear points, after a period of well production, the distribution of severely worn centralizer points on the rod string actually retrieved during well workover often deviates from the predicted eccentric wear points. Severe eccentric wear in the un-densified centralizer sections, leading to rod string breakage or tubing loss, is a frequent occurrence. Summary of the Invention

[0003] The purpose of this invention is to provide an iterative optimization method and system for preventing uneven wear based on the dynamic analysis of the sucker rod string, so as to solve the problem of rod string breakage or tubing leakage caused by severe uneven wear in the unreinforced section of the centralizer.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: The anti-wear iterative optimization method based on sucker rod string dynamics analysis includes: Based on the well inclination angle, azimuth angle and corresponding well depth, a wellbore trajectory model in a spatial rectangular coordinate system is established; Based on the wellbore trajectory model in a spatial rectangular coordinate system, crude oil viscosity-temperature curves and dynamic fluid level data of a single well are collected to calculate the position of the neutral point when the rod string descends. Based on the position of the neutral point during the downward movement of the sucker rod string, and combined with the wear of the corresponding centralizer, the magnitude of the lateral force at any point during the downward movement of the sucker rod string, as well as the centralizer installation density at the target depth, are described. By combining the difference between the centralizer density and actual wear of the rod string at different depths in a single well and the calculated difference between the centralizer installation density at the target depth, the optimization was completed through iterative prediction until the calculated results matched the actual wear.

[0005] Furthermore, the step of establishing a wellbore trajectory model in a spatial rectangular coordinate system based on the well inclination angle, azimuth angle, and corresponding well depth includes: Collect single-well data, and establish a spatial rectangular coordinate system to describe the wellbore trajectory based on the well inclination angle, azimuth angle and corresponding well depth; establish a Pxyz spatial rectangular coordinate system with the wellhead as the origin P; use the radius vector r0 to describe the position of any point on the three-dimensional wellbore trajectory; Its expression is:

[0006] The corresponding spatial geometric relation is:

[0007] The expressions for the curvature k0 and torsion T0 at the corresponding positions on the wellbore trajectory curve are as follows:

[0008] In the formula, α is the well inclination angle (rad); φ is the azimuth angle (rad); and s is the wellbore arc length (m).

[0009] Further: The dynamic position of the sucker rod system during its vertical movement in a three-dimensional wellbore space is described using the infinitesimal vector method: During the movement of the sucker rod string system, the spatial position r of any point C on it at any time t is... C (s,t) can be determined by its initial position r0(s) and displacement function u(s,t), and their expressions are as follows:

[0010]

[0011] Its corresponding position curvature k C and torsion T C The calculation formulas are as follows:

[0012] In the formula, r represents the effective clearance between the sucker rod string and the wellbore, in meters (m); θ represents the deflection angle, in rad.

[0013] Furthermore, based on the wellbore trajectory model in a spatial rectangular coordinate system, crude oil viscosity-temperature curve data for a single well are collected, and the position of the neutral point during the rod string's descent is calculated, including: The resistance p generated when well fluid flows through the moving valve lr :

[0014] Where: μ l Where m is the viscosity of the well fluid; D = 0. t / D r D t D is the inner diameter of the oil pipe. rV is the outer diameter of the sucker rod. max V is the maximum downward velocity of the sucker rod string. max =πSn / 60, where S is the stroke of the pumping unit and n is the number of strokes of the pumping unit; The frictional resistance p of the well fluid between the plunger and the pump barrel during the plunger's descent. p :

[0015] Frictional resistance of well fluid to sucker rod and frictional resistance of well fluid to centralizer:

[0016] Based on the above calculated values ​​of downward resistance, determine the position L of the neutral point during the downward movement of the rod. c : .

[0017] Furthermore, the description of the magnitude of the lateral force at any point during the downward movement of the sucker rod string, based on the position of the neutral point during the rod string's descent and the corresponding wear of the centralizer, as well as the centralizer installation density at the target depth, includes: Based on the wear patterns of centralizers retrieved at different locations during historical well operations, and combined with corresponding wear resistance test data, the magnitude of the lateral force at any point during the downward movement of the sucker rod string is described, and the centralizer insertion density for the corresponding well section is optimized: Lateral force F at a specific depth c The calculation formula is:

[0018] In the formula M p — Wear of the centralizer; E— Elastic modulus of the sucker rod, N / m 2 I—Moment of inertia of the column section, N / m 2 .

[0019] Recommended centralizer installation density at target depth l f for:

[0020] In the formula H t —Design depth; C m —For single-well empirical parameters, the initial value is recommended to be 1.25; Based on the difference between the calculated results and the actual wear of the rod column during operation, the empirical parameter C can be adjusted. m Adjustments were made to approximate the actual wear pattern.

[0021] Furthermore, the wear resistance of the friction-affected parts on the centralizer used in a single well was tested to obtain the wear amount M of the centralizer. pBased on the specific distribution location of the centralizer, the wellbore trajectory model in a spatial rectangular coordinate system is used to describe its position.

[0022] Furthermore, the optimization process involves iteratively predicting the difference between the centralizer density and actual wear conditions of historical rod strings at different depths in a single well and the centralizer installation density at the target depth, until the calculated results match the actual wear conditions. This optimization includes: The anti-wear design of the newly entered well rod string is carried out using an iteratively optimized formula. After the designed rod string is pulled out in the next operation, the predicted value and the actual distribution of wear points are compared again, and the anti-wear design formula under the latest working conditions of a single well is obtained.

[0023] Secondly, the present invention provides an anti-wear iterative optimization system based on sucker rod string dynamics analysis, comprising: The model building module is used to establish a wellbore trajectory model in a spatial rectangular coordinate system based on the well inclination angle, azimuth angle and corresponding well depth of the oil well; The neutral point location calculation module is used to collect crude oil viscosity-temperature curve data of a single well based on a wellbore trajectory model in a spatial rectangular coordinate system, and to calculate the position of the neutral point when the rod string descends. The centralizer installation density calculation module is used to describe the magnitude of the lateral force at any point during the downward movement of the sucker rod string, as well as the centralizer installation density at the target depth, based on the position of the neutral point during the rod string's descent and the corresponding wear of the centralizer. The output module is used to combine the centralizer density and actual wear conditions of the historical rod string at different depths in a single well with the difference calculated from the centralizer installation density at the target depth, and iteratively predict until the calculation results match the actual wear conditions, thus completing the optimization.

[0024] Thirdly, the present invention provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the anti-wear iterative optimization method based on sucker rod string dynamic analysis.

[0025] Fourthly, the present invention provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps of the anti-wear iterative optimization method based on sucker rod string dynamics analysis.

[0026] Compared with the prior art, the present invention has the following technical effects: This invention not only considers the traditional well trajectory and the lateral force formed by the downward bending of the sucker rod and its contact with the tubing wall, but also dynamically combines the dynamic fluid level changes at different production stages of a single well, the wear resistance test data of the centralizer, and the centralizer wear during actual rod string retrieval. This multi-dimensional data fusion makes the wear prediction model closer to the actual field conditions, and the prediction results more accurate.

[0027] By continuously comparing the predicted results with the actual wear conditions, and adjusting the empirical parameters, the prediction model gradually approximates the real situation. This iterative optimization method ensures the continuous improvement and accuracy of the prediction results.

[0028] The anti-eccentric wear design method proposed in this invention transforms the complex problem of eccentric wear into a series of calculable formulas and steps. Designers only need to input the key parameters into the relevant formulas and follow the design steps to obtain the location and quantity of centralizers required at various points throughout the wellbore. This greatly simplifies the design process and reduces the workload of designers.

[0029] The simplified design process allows designers to complete anti-wear designs more quickly, improving efficiency. At the same time, accurate predictions reduce wear issues caused by improper design, further saving costs and time associated with subsequent repairs and replacement of the rods.

[0030] This invention has achieved significant results in its cumulative application in pumping wells in the Tarim Basin. By optimizing the position and number of centralizers, it effectively reduced the problem of uneven wear of the sucker rod string and extended the inspection and pumping cycle. The average inspection and pumping cycle of five wells was increased by 112 days, greatly improving the production efficiency and economic benefits of the oil wells.

[0031] The reduction in uneven wear issues has ensured continuous and efficient production from the oil wells. This not only increases oil production but also reduces downtime for maintenance due to uneven wear, further enhancing the wells' production efficiency.

[0032] The technical solution of this invention is applicable to various types of oil wells and sucker rod string systems. Regardless of changes in the well inclination angle or azimuth angle, or differences in the material and specifications of the sucker rod string, the method of this invention can be applied by adjusting relevant parameters. Because the technical solution of this invention has advantages such as simple operation, significant effects, and wide applicability, it has high promotional value. It can provide oilfield enterprises with a new and more effective anti-wear design method, helping them improve production efficiency, reduce production costs, and extend well life.

[0033] In summary, the technical solution of this invention, through iterative optimization, significantly improves the accuracy and practicality of the anti-wear design for sucker rod strings. It not only simplifies the design process and improves work efficiency but also achieves significant field application results, demonstrating broad applicability and promotional value. Attached Figure Description

[0034] Figure 1 This is a flowchart of the present invention. Detailed Implementation

[0035] The present invention will be further described below with reference to the accompanying drawings: Example 1, please refer to Figure 1 This invention provides an iterative optimization method for preventing uneven wear based on the dynamic analysis of the sucker rod string, including: Based on the well inclination angle, azimuth angle and corresponding well depth, a wellbore trajectory model in a spatial rectangular coordinate system is established; Based on the wellbore trajectory model in a spatial rectangular coordinate system, crude oil viscosity-temperature curve data of a single well are collected, and the position of the neutral point is calculated when the rod string descends. Based on the position of the neutral point during the downward movement of the sucker rod string, and combined with the wear of the corresponding centralizer, the magnitude of the lateral force at any point during the downward movement of the sucker rod string, as well as the centralizer installation density at the target depth, are described. By combining the difference between the centralizer density and actual wear of the rod string at different depths in a single well and the calculated difference between the centralizer installation density at the target depth, the optimization was completed through iterative prediction until the calculated results matched the actual wear.

[0036] By establishing a wellbore trajectory model in a spatial rectangular coordinate system based on the well inclination angle, azimuth angle, and corresponding well depth, this method achieves an accurate description of the well trajectory. This refined modeling provides accurate basic data for subsequent dynamic analysis and wear prediction.

[0037] When calculating the neutral point position during the rod string's descent, this method considers not only the wellbore trajectory but also the viscosity-temperature curve data of the crude oil, making the prediction results closer to actual operating conditions. Furthermore, by incorporating the wear of the centralizer to predict lateral forces, the accuracy of eccentric wear prediction is further improved.

[0038] Based on the predicted position of the neutral point and lateral force during the rod string's descent, this method can provide scientific guidance for the centralizer installation density at the target depth. A reasonable centralizer layout can effectively reduce uneven wear of the sucker rod string during descent.

[0039] By continuously comparing the predicted results with the actual wear situation, this method can gradually approach the optimal solution, making the installation density and position of the stabilizer more in line with actual needs, thereby achieving the best anti-wear effect.

[0040] Uneven wear is one of the main causes of sucker rod string failure and well shutdown. Optimizing the centralizer layout using this method can effectively extend the well's production cycle and reduce shutdowns and maintenance costs caused by uneven wear.

[0041] Uneven wear not only affects the production efficiency of oil wells but can also lead to safety accidents. This method reduces uneven wear, thereby lowering the risk of safety accidents and improving the safety of oil wells.

[0042] This method relies on a large amount of oil well data and centralizer wear data for prediction and optimization. With the continuous development of data acquisition and transmission technologies, this method can more easily obtain the required data and realize intelligent and automated decision-making processes.

[0043] The framework and algorithm design of this method have good scalability and integrability. It can be integrated with other oil well management systems or smart oilfield platforms to achieve data sharing and collaborative optimization, further improving the management level and production efficiency of oil wells.

[0044] In summary, the anti-wear iterative optimization method based on sucker rod string dynamics analysis has significant technical effects in improving the accuracy of wear prediction, optimizing centralizer layout, enhancing oil well production efficiency and safety, and promoting intelligent and automated development. This method provides a new approach and methodology for oil well anti-wear design, which is of great significance for improving oil well production efficiency and extending production cycles.

[0045] Example 2: This invention provides an iterative optimization method for preventing uneven wear based on the dynamic analysis of the sucker rod string, specifically including: This invention designs an iterative optimization method for anti-wear design of the sucker rod string by combining a three-dimensional dynamic mechanical model of the sucker rod string system with the original well's rod string wear condition, and adjusting the sucker rod string design parameters, mainly the rod string assembly, pump diameter, and centralizer density. The implementation steps are as follows: Step 1: Collect single-well data. Based on the well inclination angle, azimuth angle, and corresponding well depth, establish a spatial rectangular coordinate system to describe the wellbore trajectory. Establish a Pxyz spatial rectangular coordinate system with the wellhead as the origin P. Use the radius vector r0 to describe the position of any point on the three-dimensional wellbore trajectory; its expression is:

[0046] The corresponding spatial geometric relation is:

[0047] The expressions for the curvature k0 and torsion T0 at the corresponding positions on the wellbore trajectory curve are as follows:

[0048] In the formula, α is the well inclination angle (rad); φ is the azimuth angle (rad); and s is the wellbore arc length (m).

[0049] Based on this three-dimensional wellbore trajectory description method, the infinitesimal vector method is applied to further describe the dynamic position of the sucker rod system during its up-and-down movement in the three-dimensional wellbore space.

[0050] During the movement of the sucker rod string system, the spatial position r of any point C on it at any time t is... C (s,t) can be determined by its initial position r0(s) and displacement function u(s,t), and their expressions are as follows:

[0051]

[0052] Its corresponding position curvature k C and torsion T C The calculation formulas are as follows:

[0053] In the formula, r represents the effective clearance between the sucker rod string and the wellbore, in meters (m); θ represents the deflection angle, in rad. Step 2: Test the wear resistance of the friction-affected parts (i.e., centralizing blocks) on the centralizers used in a single well. The test method refers to the pin plate test device used in section 6.4 of the standard "GB T 19831.3-2023 Oil and Gas Industry Casing Centralizers Part 3: Rigid and Semi-rigid Centralizers" for the wear measurement; the wear measurement M of the centralizing blocks mentioned later in this invention... p The average wear amount M was measured using the test method in this standard. p The test results are recorded in the following sample table:

[0054] Step 3: Collect historical information on centralizer usage in a single well, including the wear resistance of the centralizers, their specific distribution location (on which sucker rod; if no specific location is recorded, it can be estimated based on the total number of centralizers), and describe their location using a 3D well trajectory model.

[0055] Step 4: Collect crude oil viscosity-temperature curve data from individual wells, and calculate them using the following empirical formulas: The resistance p generated when well fluid flows through the moving valve lr：

[0056] Where: μ l Where m is the viscosity of the well fluid; D = 0. t / D r D t D is the inner diameter of the oil pipe. r V is the outer diameter of the sucker rod. max V is the maximum downward velocity of the sucker rod string. max =πSn / 60, where S is the stroke of the pumping unit and n is the number of strokes of the pumping unit; The frictional resistance p of the well fluid between the plunger and the pump barrel during the plunger's descent. p :

[0057] Frictional resistance of well fluid to sucker rod and frictional resistance of well fluid to centralizer:

[0058] Based on the above calculated values ​​of downward resistance, determine the position Lc of the neutral point during the downward movement of the rod:

[0059] Step 5: Based on the wear patterns of centralizers at different locations retrieved during historical operations of a single well, and combined with corresponding wear resistance test data, describe the magnitude of the lateral force at any point during the descent of the sucker rod string, and optimize the centralizer insertion density for the corresponding well section: Lateral force F at a specific depth c The calculation formula is:

[0060] In the formula M p — Wear of the centralizer; E— Elastic modulus of the sucker rod, N / m 2 I—Moment of inertia of the column section, N / m 2 .

[0061] Recommended centralizer installation density at target depth l f for:

[0062] In the formula H t —Design depth; C m —For single-well empirical parameters, the initial value is recommended to be 1.25; Based on the difference between the calculated results and the actual wear of the rod column during operation, the empirical parameter C can be adjusted. m Adjustments were made to approximate the actual wear pattern; Step 6: Combining the difference between the centralizer density and the actual wear condition of the rod string at different depths in a single well and the predicted centralizer density, change the corresponding parameters and try to change different empirical parameters. Continue to iterate the prediction until the calculation results match the actual wear condition everywhere. Then use the latest iteratively optimized formula to design the anti-wear of the new well rod string. After the designed rod string is pulled out in the next operation, continue to compare the predicted value with the actual wear point distribution, and continue to improve the anti-wear design formula under the latest working conditions of the single well.

[0063] This invention provides a theoretical prediction of the wear point location of the sucker rod string system. It not only includes the common prediction method of combining the well trajectory with the lateral force formed by the pressure bending of the sucker rod during descent and its contact with the tubing wall, but also dynamically combines the dynamic fluid level changes of a single well at different production stages, the wear resistance test data of the centralizer used, and the actual centralizer wear condition of the retrieved rod string. The wear prediction model is iteratively optimized to be closer to the actual field conditions. In actual use, the predicted wear point matches the actual wear condition of the retrieved rod string during well workover wells quite well.

[0064] The anti-wear design method proposed in this invention is highly feasible. By simply inputting key parameters into relevant formulas and completing the design steps, the location and quantity of centralizers required throughout the wellbore can be determined, reducing the workload of designers and improving work efficiency. Currently, this invention has been used in 12 pumping wells in the Tarim Basin, all maintaining continuous and efficient production. In 5 wells, the number of operating days after this pumping operation has exceeded the previous pumping cycle, with the average pumping cycle increased to 112 days, demonstrating significant application results.

[0065] In another embodiment of the present invention, an anti-wear iterative optimization system based on sucker rod string dynamics analysis is provided, which can be used to implement the above-mentioned anti-wear iterative optimization method based on sucker rod string dynamics analysis. Specifically, the system includes: The model building module is used to establish a wellbore trajectory model in a spatial rectangular coordinate system based on the well inclination angle, azimuth angle and corresponding well depth of the oil well; The neutral point location calculation module is used to collect crude oil viscosity-temperature curve data of a single well based on a wellbore trajectory model in a spatial rectangular coordinate system, and to calculate the position of the neutral point when the rod string descends. The centralizer installation density calculation module is used to describe the magnitude of the lateral force at any point during the downward movement of the sucker rod string, as well as the centralizer installation density at the target depth, based on the position of the neutral point during the rod string's descent and the corresponding wear of the centralizer. The output module is used to combine the centralizer density and actual wear conditions of the historical rod string at different depths in a single well with the difference calculated from the centralizer installation density at the target depth, and iteratively predict until the calculation results match the actual wear conditions, thus completing the optimization.

[0066] The module division in this embodiment of the invention is illustrative and represents only one logical functional division. In actual implementation, other division methods may be used. Furthermore, the functional modules in the various embodiments of the invention can be integrated into a single processor, exist as separate physical entities, or be integrated into a single module. The integrated modules described above can be implemented in hardware or as software functional modules.

[0067] In another embodiment of the present invention, a computer device is provided, comprising a processor and a memory. The memory stores a computer program, which includes program instructions. The processor executes the program instructions stored in the computer storage medium. The processor may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing and control core of the terminal, suitable for implementing one or more instructions, specifically suitable for loading and executing one or more instructions in the computer storage medium to achieve a corresponding method flow or corresponding function. The processor described in this embodiment of the present invention can be used for the operation of an anti-wear iterative optimization method based on sucker rod column dynamic analysis.

[0068] In another embodiment of the present invention, a storage medium is provided, specifically a computer-readable storage medium (Memory), which is a memory device in a computer device used to store programs and data. It is understood that the computer-readable storage medium here can include both the built-in storage medium in the computer device and extended storage media supported by the computer device. The computer-readable storage medium provides storage space that stores the terminal's operating system. Furthermore, the storage space also stores one or more instructions suitable for loading and execution by a processor. These instructions can be one or more computer programs (including program code). It should be noted that the computer-readable storage medium here can be a high-speed RAM memory or a non-volatile memory, such as at least one disk storage device. The processor can load and execute one or more instructions stored in the computer-readable storage medium to implement the corresponding steps of the anti-wear iterative optimization method based on sucker rod column dynamics analysis in the above embodiments.

[0069] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0070] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0071] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0072] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0073] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. An iterative optimization method for preventing uneven wear based on the dynamic analysis of the sucker rod string, characterized in that, include: Based on the well inclination angle, azimuth angle and corresponding well depth, a wellbore trajectory model in a spatial rectangular coordinate system is established; Based on the wellbore trajectory model in a spatial rectangular coordinate system, crude oil viscosity-temperature curves and dynamic fluid level data of a single well are collected to calculate the position of the neutral point when the rod string descends. Based on the position of the neutral point during the downward movement of the sucker rod string, and combined with the wear of the corresponding centralizer, the magnitude of the lateral force at any point during the downward movement of the sucker rod string, as well as the centralizer installation density at the target depth, are described. By combining the difference between the centralizer density and actual wear of the rod string at different depths in a single well and the calculated difference between the centralizer installation density at the target depth, the optimization was completed through iterative prediction until the calculated results matched the actual wear.

2. The anti-wear iterative optimization method based on sucker rod string dynamics analysis according to claim 1, characterized in that, The process of establishing a wellbore trajectory model in a spatial rectangular coordinate system based on the well inclination angle, azimuth angle, and corresponding well depth includes: Collect single-well data, and establish a spatial rectangular coordinate system to describe the wellbore trajectory based on the well inclination angle, azimuth angle and corresponding well depth; establish a Pxyz spatial rectangular coordinate system with the wellhead as the origin P; use the radius vector r0 to describe the position of any point on the three-dimensional wellbore trajectory; Its expression is: The corresponding spatial geometric relation is: The expressions for the curvature k0 and torsion T0 at the corresponding positions on the wellbore trajectory curve are as follows: In the formula, α is the well inclination angle (rad); φ is the azimuth angle (rad); and s is the wellbore arc length (m).

3. The anti-wear iterative optimization method based on sucker rod string dynamics analysis according to claim 1, characterized in that, Further: The dynamic position of the sucker rod system during its vertical movement in a three-dimensional wellbore space is described using the infinitesimal vector method: During the movement of the sucker rod string system, the spatial position r of any point C on it at any time t is... C (s,t) can be determined by its initial position r0(s) and displacement function u(s,t), and their expressions are as follows: Its corresponding position curvature k C and torsion T C The calculation formulas are as follows: In the formula, r represents the effective clearance between the sucker rod string and the wellbore, in meters (m); θ represents the deflection angle, in rad.

4. The anti-wear iterative optimization method based on sucker rod string dynamics analysis according to claim 1, characterized in that, Based on a wellbore trajectory model in a spatial rectangular coordinate system, crude oil viscosity-temperature curve data for a single well are collected, and the position of the neutral point during the rod string's descent is calculated, including: The resistance p generated when well fluid flows through the moving valve lr : Where: μ l The viscosity of the well fluid is m = D. t / D r D t D is the inner diameter of the oil pipe. r V is the outer diameter of the sucker rod. max V is the maximum downward velocity of the sucker rod string. max =πSn / 60, where S is the stroke of the pumping unit and n is the number of strokes of the pumping unit; The frictional resistance p of the well fluid between the plunger and the pump barrel during the plunger's descent. p : Frictional resistance of well fluid to sucker rod and frictional resistance of well fluid to centralizer: Based on the above calculated values ​​of downward resistance, determine the position L of the neutral point during the downward movement of the rod. c : 。 5. The anti-wear iterative optimization method based on sucker rod string dynamics analysis according to claim 1, characterized in that, The description of the lateral force at any point during the downward movement of the sucker rod string, based on the position of the neutral point and the wear of the corresponding centralizer, as well as the centralizer installation density at the target depth, includes: Based on the wear patterns of centralizers retrieved at different locations during historical well operations, and combined with corresponding wear resistance test data, the magnitude of the lateral force at any point during the downward movement of the sucker rod string is described, and the centralizer insertion density for the corresponding well section is optimized: Lateral force F at a specific depth c The calculation formula is: In the formula M p — Wear of the centralizer; E— Elastic modulus of the sucker rod, N / m 2 I—Moment of inertia of the column section, N / m 2 ; Centralizer installation density at target depth l f for: In the formula H t —Design depth; C m —For single-well empirical parameters, the initial value is recommended to be 1.25; Based on the difference between the calculated results and the actual wear of the rod column during operation, the empirical parameter C can be adjusted. m Adjustments were made to approximate the actual wear pattern.

6. The anti-wear iterative optimization method based on sucker rod string dynamics analysis according to claim 5, characterized in that, The wear resistance of the friction-exposed parts of the centralizer used in a single well was tested to obtain the wear amount M of the centralizer. p Based on the specific distribution location of the centralizer, the wellbore trajectory model in a spatial rectangular coordinate system is used to describe its position.

7. The anti-wear iterative optimization method based on sucker rod string dynamics analysis according to claim 1, characterized in that, The optimization process involves iteratively predicting the difference between the centralizer density and actual wear conditions at different depths in a single well and the centralizer installation density at the target depth, until the calculated results match the actual wear conditions. This includes: The anti-wear design of the newly entered well rod string is carried out using an iteratively optimized formula. After the designed rod string is pulled out in the next operation, the predicted value and the actual distribution of wear points are compared again, and the anti-wear design formula under the latest working conditions of a single well is obtained.

8. An anti-wear iterative optimization system based on sucker rod string dynamics analysis, characterized in that, include: The model building module is used to establish a wellbore trajectory model in a spatial rectangular coordinate system based on the well inclination angle, azimuth angle and corresponding well depth of the oil well; The neutral point location calculation module is used to collect crude oil viscosity-temperature curve data of a single well based on a wellbore trajectory model in a spatial rectangular coordinate system, and to calculate the position of the neutral point when the rod string descends. The centralizer installation density calculation module is used to describe the magnitude of the lateral force at any point during the downward movement of the sucker rod string, as well as the centralizer installation density at the target depth, based on the position of the neutral point during the rod string's descent and the corresponding wear of the centralizer. The output module is used to combine the centralizer density and actual wear conditions of the historical rod string at different depths in a single well with the difference calculated from the centralizer installation density at the target depth, and iteratively predict until the calculation results match the actual wear conditions, thus completing the optimization.

9. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the anti-wear iterative optimization method based on sucker rod string dynamic analysis as described in any one of claims 1 to 7.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the anti-wear iterative optimization method based on the dynamic analysis of the sucker rod column as described in any one of claims 1 to 7.

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