Method and device for determining safe service time of casing pup joint, medium and electronic equipment

Abstract

The invention discloses a method and a device for determining safe service time of a casing pup joint, a medium and electronic equipment. The method comprises the steps that according to the current geological condition of an injection and production well, the position of surface water connected with a casing pipe pup joint is judged, and the position of the surface water is set as the corrosion core position of the casing pipe pup joint; calculating the total radial stress, the total circumferential stress and the total axial stress corresponding to the corrosion core position under the initial time node so as to calculate the equivalent stress corresponding to the corrosion core position under the initial time node; and according to the equivalent stress and the yield strength, the safe service time of the casing pup joint is determined. According to the method, the accuracy of calculating the safe service time of the casing pup joint can be improved.

Description

Background Art

[0002] At present, casing short-circuiting, as an important part of wellbore integrity, is directly related to whether oil and gas can be produced safely and smoothly. If corrosion occurs due to the external environment, it will inevitably affect the safe production of injection and production wells, affect the operation of injection and production wells, and even cause major safety accidents.

[0003] In some oil fields, casing short-circuit is immersed in surface water, and serious dissolved oxygen corrosion will occur at the interface with water. Coupled with the influence of other external factors such as injection and production pressure, casing short-circuit will be perforated and misaligned, causing steam and crude oil leakage at some wellheads, and even wellhead sinking and other dangerous situations, greatly shortening its safe use time.

[0004] Based on this, how to determine the safe service time of casing short circuit is a technical problem that needs to be solved urgently. Summary of the invention

[0005] The purpose of the present application is to provide a method, device, medium and electronic device for determining the safe service time of a casing short circuit. The present application can improve the accuracy of calculating the safe service time of a casing short circuit.

[0006] Other features and advantages of the present application will become apparent from the following detailed description, or may be learned in part by the practice of the present application.

[0007] According to one aspect of an embodiment of the present application, a method for determining the safe service time of a casing short circuit is provided, characterized in that the method includes: judging the position of surface water short-circuited with the casing according to the current geological conditions of the injection and production well, and setting the position of the surface water as the corrosion core position of the casing short circuit; calculating the total radial stress, total circumferential stress and total axial stress corresponding to the corrosion core position at the initial time node, thereby calculating the equivalent stress corresponding to the corrosion core position at the initial time node; determining the safe service time of the casing short circuit according to the equivalent stress and yield strength.

[0008] In one embodiment of the present application, based on the aforementioned scheme, the safe service time of the casing short circuit is determined according to the equivalent stress and yield strength, including: if the equivalent stress is less than the yield strength, the next time node is used as a new initial time node, and a cumulative node number is increased, the new initial time node is separated from the previous initial time node by a unit interval time, and the initial value of the cumulative node number is zero; according to the new initial time node, the total radial stress, total circumferential stress and total axial stress corresponding to the corrosion core position at the initial time node are re-calculated, thereby calculating the equivalent stress corresponding to the corrosion core position at the initial time node.

[0009] In one embodiment of the present application, based on the aforementioned scheme, determining the safe service time of the casing short circuit according to the equivalent stress includes: if the equivalent stress is greater than the yield strength, calculating the safe service time of the casing short circuit based on the unit interval time and the cumulative number of nodes.

[0010] In one embodiment of the present application, based on the above scheme, the total radial stress is calculated by the following formula:

[0011] σ r =σ r ′+σ r ″

[0012] Among them, σ r is the total radial stress, MPa; σ r ′ is the radial stress generated by the internal pressure and external extrusion force at the core position of the casing short-circuit corrosion, MPa; σ r ″ is the radial stress generated by heat at the core position of casing short-circuit corrosion, MPa.

[0013] In one embodiment of the present application, based on the above scheme, the total circumferential stress is calculated by the following formula:

[0014] σ θ =σ θ ′+σ θ ″

[0015] Among them, σ θ is the total circumferential stress, MPa; σ θ ′ is the circumferential stress generated by the internal pressure and external extrusion force at the core position of the casing short-circuit corrosion, MPa; σ θ ″ is the circumferential stress generated by heat at the core position of casing short-circuit corrosion, MPa.

[0016] In one embodiment of the present application, based on the above scheme, the total axial stress is calculated by the following formula:

[0017] σ z =σ zo +σ zb +σ z ′+σ z ″

[0018] Among them, σ z is the total axial stress, MPa; σ zo is the initial axial stress generated by the deadweight and buoyancy at the core of the casing short-circuit corrosion, MPa; zb is the axial stress generated by the bending of the tubing at the core position of the casing short-circuit corrosion, MPa; σ z′ is the axial stress generated by the internal pressure and external extrusion force at the core position of the casing short-circuit corrosion, MPa; σ z ″ is the axial stress generated by heat at the core position of casing short-circuit corrosion, MPa.

[0019] In one embodiment of the present application, based on the above solution, the equivalent stress is calculated by the following formula:

[0020]

[0021] Among them, σ equ is the equivalent stress, MPa; σ r is the total radial stress, MPa; σ θ is the total circumferential stress, MPa; σ z is the total axial stress, MPa.

[0022] According to one aspect of an embodiment of the present application, a device for determining the safe service time of a casing short circuit is provided, characterized in that the device includes: a judgment unit, used to judge the position of surface water short-circuited with the casing according to the current geological conditions of the injection and production well, and set the position of the surface water as the corrosion core position of the casing short circuit; a first calculation unit, used to calculate the total radial stress, total circumferential stress and total axial stress corresponding to the corrosion core position at an initial time node, thereby calculating the equivalent stress corresponding to the corrosion core position at the initial time node; a second calculation unit, used to determine the safe service time of the casing short circuit according to the equivalent stress and yield strength.

[0023] According to one aspect of an embodiment of the present application, a computer-readable storage medium is provided, on which a computer program is stored. The computer program includes executable instructions. When the executable instructions are executed by a processor, the method described in the above embodiment is implemented.

[0024] According to one aspect of an embodiment of the present application, an electronic device is provided, comprising: one or more processors; and a memory for storing executable instructions of the processors, wherein when the executable instructions are executed by the one or more processors, the one or more processors implement the methods described in the above embodiments.

[0025] In the technical solution of the embodiment of the present application, the corrosion core position of the casing short circuit is firstly obtained, and the total radial stress, total circumferential stress and total axial stress corresponding to the corrosion core position are calculated.

[0026] After calculating the total radial stress, total circumferential stress and total axial stress, the equivalent stress corresponding to the corrosion core position can be calculated. By judging whether the equivalent stress at the corrosion core position of the current casing short circuit is less than the yield strength of the casing short circuit under the current material, the safe service time of the casing short circuit can be determined. Among them, if the equivalent stress is less than the yield strength, the next time node is used as the new initial time node, and a cumulative node number is added. According to the new initial time node, the steps of calculating the total radial stress, total circumferential stress and total axial stress corresponding to the corrosion core position at the initial time node are re-executed to calculate the equivalent stress corresponding to the corrosion core position at the initial time node. If the equivalent stress is greater than the yield strength, the safe service time of the casing short circuit is calculated based on the unit interval time and the cumulative number of nodes.

[0027] Therefore, the method for determining the safe service time of casing short circuit based on the present application can improve the accuracy of calculating the safe service time of casing short circuit, and can provide a basis for the wellbore integrity and the safe operation and maintenance of injection and production wells.

[0028] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The drawings herein are incorporated into the specification and constitute a part of the specification, showing embodiments consistent with the present application, and together with the specification, are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0030] Figure 1 It is a flow chart of a method for determining the safe service time of a casing short circuit according to an embodiment of the present application;

[0031] Figure 2 It is a block diagram of a device for determining the safe service time of a bushing short circuit according to an embodiment of the present application;

[0032] Figure 3 It is a schematic diagram of the system structure of an electronic device according to an embodiment of the present application. DETAILED DESCRIPTION

[0033] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this application will be more comprehensive and complete and fully convey the concept of the example embodiments to those skilled in the art.

[0034] In addition, described feature, structure or characteristic can be combined in one or more embodiments in any suitable manner. In the following description, many specific details are provided to provide a full understanding of the embodiments of the present application. However, those skilled in the art will appreciate that the technical scheme of the present application can be put into practice without one or more of the specific details, or other methods, components, devices, steps, etc. can be adopted. In other cases, known methods, devices, realizations or operations are not shown or described in detail to avoid blurring the various aspects of the application.

[0035] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities may be implemented in software form, or in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices.

[0036] The flowcharts shown in the accompanying drawings are only exemplary and do not necessarily include all the contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps can be decomposed, and some operations / steps can be combined or partially combined, so the actual execution order may change according to actual conditions.

[0037] It should be noted that the "multiple" mentioned in this article refers to two or more. "And / or" describes the association relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the associated objects before and after are in an "or" relationship.

[0038] The implementation details of the technical solution of the embodiment of the present application are described in detail below:

[0039] According to one aspect of the present application, a method for determining the safe service time of a casing short circuit is provided. Figure 1 The flowchart of the method for determining the safe service time of a casing short circuit according to an embodiment of the present application is shown. The method for determining the safe service time of a casing short circuit can be executed by a device with a computing and processing function. The method for determining the safe service time of a casing short circuit includes at least steps 110 to 130, which are described in detail as follows:

[0040] In step 110, the position of the surface water short-circuited with the casing is determined according to the current geological conditions of the injection-production well, and the position of the surface water is set as the corrosion core position of the casing short-circuited.

[0041] In this application, casing short-circuit is an important part of wellbore integrity and is directly related to whether oil and gas can be produced safely and smoothly. If corrosion occurs due to the external environment, it will inevitably affect the safe production of injection and production wells, affect the operation of injection and production wells, and even cause major safety accidents. Therefore, it is necessary to analyze the core position of the corrosion of the casing short-circuit, so as to calculate the safe service time of the casing short-circuit in a targeted manner.

[0042] Since the casing short-circuit is in an environment of surface water corrosion, the humidity and air content at the junction of the casing short-circuit and the surface water are relatively high. The casing short-circuit is prone to severe dissolved oxygen corrosion at the junction with the surface water. Based on this, the junction of the casing short-circuit and the surface water is set as the corrosion core position of the casing short-circuit.

[0043] Continue to refer to Figure 1 In step 120, the total radial stress, total circumferential stress and total axial stress corresponding to the corrosion core position at the initial time node are calculated, thereby calculating the equivalent stress corresponding to the corrosion core position at the initial time node.

[0044] In this application, the casing short circuit will be affected by stress in different directions during the corrosion process, among which the main influencing factor for the casing short circuit corrosion is the equivalent stress corresponding to the corrosion core position. The calculation of the equivalent stress requires first calculating the total radial stress, total circumferential stress and total axial stress corresponding to the corrosion core position.

[0045] Specifically, the total radial stress is calculated by the following formula:

[0046] σ r =σ r ′+σ r ″

[0047] Among them, σ r is the total radial stress, MPa; σ r ′ is the radial stress generated by the internal pressure and external extrusion force at the core position of the casing short-circuit corrosion, MPa; σ r ″ is the radial stress generated by heat at the core position of casing short-circuit corrosion, MPa.

[0048] Furthermore, the radial stress (i.e., σ r ′) can be calculated by the following formula:

[0049]

[0050] Among them, P i is the external squeeze force at the core position of casing short-circuit corrosion, MPa; P ois the internal pressure at the core of the casing short-circuit corrosion, MPa; r ci is the inner radius of the casing short-circuit at the core of the casing short-circuit corrosion, mm; r co is the outer radius of the casing short-connection at the core position of the casing short-connection corrosion, mm; r is the average inner and outer radii of the casing short-connection at the core position of the casing short-connection corrosion, mm.

[0051] Furthermore, when calculating based on the inner radius of the casing short-connection and the outer radius of the casing short-connection, since the corrosion degree of the casing short-connection is constantly changing, it is necessary to calculate the inner radius of the casing short-connection and the outer radius of the casing short-connection in real time for the accuracy of the calculation. At the same time, when calculating the inner radius of the casing short-connection and the outer radius of the casing short-connection, it is necessary to calculate according to the corrosion rate of the casing short-connection under different materials.

[0052] For example, when the casing short-circuit material is N80 casing short-circuit, the corrosion rate of the casing short-circuit can be calculated by the following formula:

[0053] cor_sp N80 =-0.0005t 4 +0.00013t 3 +0.0008t 2 +0.0016t+0.0022

[0054] Among them, cor_sp N80 is the corrosion rate of casing short-circuit in surface water corrosion environment, mm / year; t is the temperature of the corrosion core position of casing short-circuit, ℃.

[0055] For example, when the casing short-circuit material is 110H casing short-circuit, the corrosion rate of the casing short-circuit can be calculated by the following formula:

[0056] cor_sp 110H =-0.0006t 4 +0.00131t 3 +0.0008t 2 +0.0015t+0.0022

[0057] Among them, cor_sp 110H is the corrosion rate of casing short-circuit in surface water corrosion environment, mm / year; t is the temperature of the corrosion core position of casing short-circuit, ℃.

[0058] For example, when the casing short-circuit material is BG130TT casing short-circuit, the corrosion rate of the casing short-circuit can be calculated by the following formula:

[0059] cor_sp BG130TT =-0.0013t 4+0.00117t 3 +0.0003t 2 +0.0009t+0.0009

[0060] Among them, cor_sp BG130TT is the corrosion rate of casing short-circuit in surface water corrosion environment, mm / year, and t is the temperature of the corrosion core position of casing short-circuit, ℃.

[0061] Furthermore, the radial stress (i.e., σ r ″) can be calculated by the following formula:

[0062]

[0063] Among them, α c The linear thermal expansion coefficient of the short-circuited sleeve at this time point, m / (m·℃); E c Elastic modulus of the casing short circuit at this time node, MPa; u c Poisson's ratio of casing short circuit at this time node; ΔT is the change in temperature between the core position of casing short circuit corrosion at this time node and the initial temperature, ℃.

[0064] Furthermore, the calculation coefficient C in the calculation formula of radial stress generated by thermal action at the core position of the casing short-circuit corrosion is c1 , which can be calculated by the following formula:

[0065]

[0066] Among them, E f Elastic modulus of surrounding rock at the core position of casing short-circuit corrosion at this time node, MPa; u f Poisson's ratio of the surrounding rock at the core location of casing short-circuit corrosion at this time node.

[0067] The total circumferential stress is calculated by the following formula:

[0068] σ θ =σ θ ′+σ θ ″

[0069] Among them, σ θ is the total circumferential stress, MPa; σ θ ′ is the circumferential stress generated by the internal pressure and external extrusion force at the core position of the casing short-circuit corrosion, MPa; σ θ ″ is the circumferential stress generated by heat at the core position of casing short-circuit corrosion, MPa.

[0070] Furthermore, the circumferential stress (i.e., σ θ ′), can be calculated by the following formula:

[0071]

[0072] Among them, P i is the external squeeze force at the core position of casing short-circuit corrosion, MPa; P o is the internal pressure at the core of the casing short-circuit corrosion, MPa; r ci is the inner radius of the casing short-circuit at the core of the casing short-circuit corrosion, mm; r co is the outer radius of the casing short-connection at the core position of the casing short-connection corrosion, mm; r is the average inner and outer radii of the casing short-connection at the core position of the casing short-connection corrosion, mm.

[0073] Furthermore, the circumferential stress (i.e., σ θ ″) can be calculated by the following formula:

[0074]

[0075] Among them, α c The linear thermal expansion coefficient of the short-circuited sleeve at this time point, m / (m·℃); E c Elastic modulus of the casing short circuit at this time node, MPa; u c Poisson's ratio of casing short circuit at this time node; ΔT is the change in temperature between the core position of casing short circuit corrosion at this time node and the initial temperature, ℃.

[0076] The total axial stress is calculated by the following formula:

[0077] σ z =σ zo +σ zb +σ z ′+σ z ″

[0078] Among them, σ z is the total axial stress, MPa; σ zo is the initial axial stress generated by the deadweight and buoyancy at the core of the casing short-circuit corrosion, MPa; zb is the axial stress generated by the bending of the tubing at the core position of the casing short-circuit corrosion, MPa; σ z ′ is the axial stress generated by the internal pressure and external extrusion force at the core position of the casing short-circuit corrosion, MPa; σ z ″ is the axial stress generated by heat at the core position of casing short-circuit corrosion, MPa.

[0079] Furthermore, the initial axial stress (i.e., σ zo ), can be calculated by the following formula:

[0080] σ zo =(ρ c l c -ρ l l l )g·10 -6

[0081] Among them, ρ c Density of casing short-circuit, kg / m 3 ρ l Density of drilling mud, kg / m 3 ; l c Casing short-circuit length from the core position of casing short-circuit corrosion to the bottom of the well, m; l l The short-circuit length of the casing from the top of the drilling mud liquid surface to the bottom of the well during well completion, m; g gravity acceleration, taken as 9.8N / kg.

[0082] Furthermore, the axial stress (i.e., σ zb ), can be calculated by the following formula:

[0083] σ zb =0.060156D leg d is

[0084] Among them, D leg The curvature of the casing at the core of the short-circuit corrosion, ° / 30m; d is —Nominal inner diameter of casing stub body, mm.

[0085] Furthermore, the axial stress (i.e., σ z ′), can be calculated by the following formula:

[0086] σ z ′=u c (σ r ′+σ θ ′)

[0087] Among them, σ r ′ is the radial stress generated by the internal pressure and external extrusion force at the core position of the casing short-circuit corrosion, MPa; σ θ ′ is the circumferential stress generated by the internal pressure and external extrusion force at the core position of the casing short-circuit corrosion, MPa; u c Poisson's ratio of the casing short circuit at this time node.

[0088] Furthermore, the axial stress (i.e., σ z ″), can be calculated by the following formula:

[0089]

[0090] Among them, α c The linear thermal expansion coefficient of the short-circuited sleeve at this time point, m / (m·℃); E c Elastic modulus of the casing short circuit at this time node, MPa; u c Poisson's ratio of casing short circuit at this time node; ΔT is the change in temperature between the core position of casing short circuit corrosion at this time node and the initial temperature, ℃.

[0091] The equivalent stress is calculated by the following formula:

[0092]

[0093] Among them, σ equ is the equivalent stress, MPa; σ r is the total radial stress, MPa; σ θ is the total circumferential stress, MPa; σ z is the total axial stress, MPa.

[0094] Continue to refer to Figure 1 In step 130, the safe service time of the casing short circuit is determined according to the equivalent stress and yield strength.

[0095] In the present application, the equivalent stress of the casing short-circuit at the corrosion core position is obtained, and the safe service time of the casing short-circuit is calculated in combination with the yield strength corresponding to the casing short-circuit.

[0096] Furthermore, after obtaining the equivalent stress and the yield strength, the method further includes steps 131 and 132:

[0097] Step 131, if the equivalent stress is less than the yield strength, the next time node is used as a new initial time node, and a cumulative node number is increased, the new initial time node is separated from the previous initial time node by a unit interval time, and the initial value of the cumulative node number is zero.

[0098] Step 132, based on the new initial time node, re-calculate the total radial stress, total circumferential stress and total axial stress corresponding to the corrosion core position at the initial time node, so as to calculate the equivalent stress corresponding to the corrosion core position at the initial time node.

[0099] In the present application, after obtaining the equivalent stress and the yield strength, if the equivalent stress is less than the yield strength, it means that the corrosion degree of the current casing short circuit is low and will not affect the normal operation of the steam injection well and the production well. Therefore, the next time node is used as a new initial time node, and the steps of calculating the total radial stress, total circumferential stress and total axial stress corresponding to the corrosion core position at the initial time node are re-executed, so as to calculate the equivalent stress corresponding to the corrosion core position at the initial time node. Among them, the new initial time node is separated from the previous initial time node by a unit interval time. In addition, in the present application, each time the step of judging whether the equivalent stress is less than the yield strength is executed, a cumulative node number needs to be added, and the cumulative node number is used to calculate the safe service time of the casing short circuit, and the initial value of the cumulative node number is zero.

[0100] Furthermore, after obtaining the equivalent stress and the yield strength, the method further includes step 133:

[0101] Step 133: If the equivalent stress is greater than the yield strength, the safe service time of the casing short circuit is calculated based on the unit interval time and the accumulated number of nodes.

[0102] In this application, if the equivalent stress is greater than the yield strength, it means that the current corrosion degree of the casing short connection is relatively large, affecting the normal operation of the steam injection well and the production well. Therefore, according to the unit interval time and the cumulative number of nodes, the safe service time of the casing short connection can be calculated.

[0103] Combining the above methods, the accuracy of calculating the safe service time of casing short circuit can be improved, and a basis can be provided for the wellbore integrity and the safe operation and maintenance of injection and production wells.

[0104] The following describes an apparatus embodiment of the present application, which can be used to execute the method for determining the safe service time of a casing short circuit in the above-mentioned embodiment of the present application. For details not disclosed in the apparatus embodiment of the present application, please refer to the embodiment of the method for determining the safe service time of a casing short circuit in the above-mentioned embodiment of the present application.

[0105] Figure 2 The block diagram is a device for determining the safe service time of a bushing short circuit according to an embodiment of the present application.

[0106] Reference Figure 2As shown, according to an embodiment of the present application, a device 200 for determining the safe service time of a casing short circuit, the device 200 includes: a judgment unit 201, used to judge the position of the surface water short-circuited with the casing according to the current geological conditions of the injection and production well, and set the position of the surface water as the corrosion core position of the casing short circuit; a first calculation unit 202, used to calculate the total radial stress, total circumferential stress and total axial stress corresponding to the corrosion core position at the initial time node, thereby calculating the equivalent stress corresponding to the corrosion core position at the initial time node; a second calculation unit 203, used to determine the safe service time of the casing short circuit according to the equivalent stress and yield strength.

[0107] As another aspect, the present application further provides a computer-readable storage medium on which a program product capable of implementing the above method of the present specification is stored. In some possible implementations, various aspects of the present application may also be implemented in the form of a program product, which includes a program code, and when the program product is run on a terminal device, the program code is used to enable the terminal device to execute the steps according to various exemplary implementations of the present application described in the above "Exemplary Method" section of the present specification.

[0108] Computer readable signal media may include data signals propagated in baseband or as part of a carrier wave, in which readable program code is carried. Such propagated data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. Readable signal media may also be any readable medium other than a readable storage medium, which may send, propagate, or transmit a program for use by or in conjunction with an instruction execution system, apparatus, or device.

[0109] The program code embodied on the readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wired, optical cable, RF, etc., or any suitable combination of the foregoing.

[0110] Program code for performing the operations of the present application may be written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Java, C++, etc., and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user computing device, partially on the user device, as a separate software package, partially on the user computing device and partially on a remote computing device, or entirely on a remote computing device or server. In the case of a remote computing device, the remote computing device may be connected to the user computing device through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computing device (e.g., using an Internet service provider to connect through the Internet).

[0111] As another aspect, the present application also provides an electronic device capable of implementing the above method.

[0112] Those skilled in the art will appreciate that various aspects of the present application may be implemented as a system, method or program product. Therefore, various aspects of the present application may be specifically implemented in the following forms, namely: a complete hardware implementation, a complete software implementation (including firmware, microcode, etc.), or a combination of hardware and software, which may be collectively referred to as "circuit", "module" or "system" herein.

[0113] Figure 3 The schematic diagram of the system structure of the electronic device according to the embodiment of the present application is shown below. Figure 3 The electronic device 300 according to this embodiment of the present application is described. Figure 3 The electronic device 300 shown is merely an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0114] like Figure 3 As shown, the electronic device 300 is in the form of a general computing device. The components of the electronic device 300 may include but are not limited to: at least one processing unit 310, at least one storage unit 320, and a bus 330 connecting different system components (including the storage unit 320 and the processing unit 310).

[0115] The storage unit stores program codes, which can be executed by the processing unit 310, so that the processing unit 310 executes the steps described in the above “Example Method” section of this specification according to various exemplary implementations of the present application.

[0116] The storage unit 320 may include a readable medium in the form of a volatile storage unit, such as a random access memory unit (RAM) 321 and / or a cache memory unit 322 , and may further include a read-only memory unit (ROM) 323 .

[0117] The storage unit 320 may also include a program / utility 324 having a set (at least one) of program modules 325, such program modules 325 including but not limited to: an operating system, one or more application programs, other program modules, and program data, each of which or some combination may include an implementation of a network environment.

[0118] Bus 330 may represent one or more of several types of bus structures, including a memory unit bus or memory unit controller, a peripheral bus, an accelerated graphics port, a processing unit, or a local bus using any of a variety of bus architectures.

[0119] The electronic device 300 may also communicate with one or more external devices 1200 (e.g., keyboards, pointing devices, Bluetooth devices, etc.), may also communicate with one or more devices that enable a user to interact with the electronic device 300, and / or communicate with any device that enables the electronic device 300 to communicate with one or more other computing devices (e.g., routers, modems, etc.). Such communication may be performed via an input / output (I / O) interface 350. Furthermore, the electronic device 300 may also communicate with one or more networks (e.g., local area networks (LANs), wide area networks (WANs), and / or public networks, such as the Internet) via a network adapter 360. As shown, the network adapter 360 communicates with other modules of the electronic device 300 via a bus 330. It should be understood that, although not shown in the figure, other hardware and / or software modules may be used in conjunction with the electronic device 300, including but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage systems.

[0120] Through the description of the above implementation methods, it is easy for those skilled in the art to understand that the example implementation methods described here can be implemented by software or by combining software with necessary hardware. Therefore, the technical solution according to the implementation methods of the present application can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which can be a CD-ROM, a USB flash drive, a mobile hard disk, etc.) or on a network, and includes several instructions to enable a computing device (which can be a personal computer, a server, a terminal device, or a network device, etc.) to execute the method according to the implementation methods of the present application.

[0121] In addition, the above-mentioned figures are only schematic illustrations of the processes included in the method according to the exemplary embodiments of the present application, and are not intended to be limiting. It is easy to understand that the processes shown in the above-mentioned figures do not indicate or limit the time sequence of these processes. In addition, it is also easy to understand that these processes can be performed synchronously or asynchronously, for example, in multiple modules.

[0122] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be performed without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A method for determining the safe service time of a casing short circuit, characterized in that: The method comprises: According to the current geological conditions of the injection-production well, the position of the surface water short-circuited with the casing is determined, and the position of the surface water is set as the corrosion core position of the casing short-circuited; Calculate the total radial stress, total circumferential stress and total axial stress corresponding to the corrosion core position at the initial time node, so as to calculate the equivalent stress corresponding to the corrosion core position at the initial time node; The safe service time of the casing short circuit is determined according to the equivalent stress and the yield strength.

2. The method according to claim 1, characterized in that: Determining the safe service time of the casing short circuit according to the equivalent stress and the yield strength includes: If the equivalent stress is less than the yield strength, the next time node is used as a new initial time node, and a cumulative node number is increased, the new initial time node is separated from the previous initial time node by a unit interval time, and the initial value of the cumulative node number is zero; According to the new initial time node, the step of calculating the total radial stress, the total circumferential stress and the total axial stress corresponding to the corrosion core position at the initial time node is re-executed, thereby calculating the equivalent stress corresponding to the corrosion core position at the initial time node.

3. The method according to claim 2, characterized in that Determining the safe service time of the casing short circuit according to the equivalent stress includes: If the equivalent stress is greater than the yield strength, the safe service time of the bushing short circuit is calculated based on the unit interval time and the accumulated number of nodes.

4. The method according to claim 1, characterized in that The total radial stress is calculated by the following formula: s r =s r ′+σ r ″ Among them, σ r is the total radial stress, MPa; σ r ′ is the radial stress generated by the internal pressure and external extrusion force at the core position of the casing short-circuit corrosion, MPa; σ r ″ is the radial stress generated by heat at the core position of casing short-circuit corrosion, MPa.

5. The method according to claim 1, characterized in that The total circumferential stress is calculated by the following formula: s θ =s θ ′+σ θ ″ Among them, σ θ is the total circumferential stress, MPa; σ θ ′ is the circumferential stress generated by the internal pressure and external extrusion force at the core position of the casing short-circuit corrosion, MPa; σ θ ″ is the circumferential stress generated by heat at the core position of casing short-circuit corrosion, MPa.

6. The method according to claim 1, characterized in that The total axial stress is calculated by the following formula: s z =s zo +s zb +s z ′+σ z ″ Among them, σ z is the total axial stress, MPa; σ zo is the initial axial stress generated by the deadweight and buoyancy at the core of the casing short-circuit corrosion, MPa; zb is the axial stress generated by the bending of the tubing at the core position of the casing short-circuit corrosion, MPa; σ z ′ is the axial stress generated by the internal pressure and external extrusion force at the core position of the casing short-circuit corrosion, MPa; σ z ″ is the axial stress generated by heat at the core position of casing short-circuit corrosion, MPa.

7. The method according to claim 1, characterized in that The equivalent stress is calculated by the following formula: Among them, σ equ is the equivalent stress, MPa; σ r is the total radial stress, MPa; σ θ is the total circumferential stress, MPa; σ z is the total axial stress, MPa.

8. A device for determining the safe service time of a casing short circuit, characterized in that: The device comprises: A judgment unit, used to judge the position of the surface water short-circuited with the casing according to the current geological conditions of the injection-production well, and set the position of the surface water as the corrosion core position of the casing short-circuited; A first calculation unit is used to calculate the total radial stress, the total circumferential stress and the total axial stress corresponding to the corrosion core position at the initial time node, so as to calculate the equivalent stress corresponding to the corrosion core position at the initial time node; The second calculation unit is used to determine the safe service time of the casing short circuit according to the equivalent stress and the yield strength.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores at least one program code, and the at least one program code is loaded and executed by a processor to implement the operations performed by the method according to any one of claims 1 to 7.

10. An electronic device, characterized in that: The electronic device includes one or more processors and one or more memories, wherein the one or more memories store at least one program code, and the at least one program code is loaded and executed by the one or more processors to implement the operations performed by the method according to any one of claims 1 to 7.

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