Method and device for determining safe service life of production string, medium and electronic equipment

Abstract

The application discloses a method and device for determining safe service time of a production string, a medium and an electronic device. The method comprises the following steps: determining a corrosion core position according to injection-production conditions of an injection-production well, wherein the corrosion core position is a position corresponding to maximum gas partial pressure of the production string; calculating equivalent stress corresponding to the corrosion core position by calculating total radial stress, total circumferential stress and total axial stress corresponding to the corrosion core position; and determining the safe service time of the production string according to the equivalent stress and yield strength corresponding to the production string. The application can improve the accuracy of calculating the safe service time of the production string.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of production string analysis, in particular, to a method and device for determining safe service time of a production string, a medium and an electronic device. BACKGROUND

[0002] At present, wellbore integrity is a prerequisite for ensuring safe and smooth production of oil and gas. If the casing of an injection-production well is damaged or changed due to external formation environment or internal injection-production conditions, the wellbore integrity will be damaged, the injection-production well operation will be affected, and even a major safety accident will be caused.

[0003] In the thermal recovery process of some oilfields, most thermal recovery wells produce H2S / CO2 / O2 gas. When the production string directly contacts the corrosive gas, the wall thickness of the production string gradually thins under the three-phase gas corrosion environment. In addition, the injection-production conditions of pressure and temperature affect the production string, causing perforation and rupture of the production string, and greatly shortening the safe service time of the production string. Therefore, how to determine the safe service time of the production string is a technical problem to be solved. SUMMARY

[0004] The purpose of the present application is to provide a method and device for determining safe service time of a production string, a medium and an electronic device. The present application can improve the accuracy of calculating the safe service time of the production string.

[0005] Other characteristics and advantages of the present application will become apparent from the following detailed description, or will be learned by practice of the present application.

[0006] According to one aspect of an embodiment of the present application, a method for determining safe service time of a production string is provided, characterized in that the method comprises: determining a corrosion core position according to injection-production conditions of an injection-production well, the corrosion core position being a position corresponding to maximum gas partial pressure of the production string; calculating equivalent stress corresponding to the corrosion core position by calculating total radial stress, total circumferential stress and total axial stress corresponding to the corrosion core position; and determining safe service time of the production string according to the equivalent stress and yield strength corresponding to the production string.

[0007] In one embodiment of the present application, based on the foregoing scheme, the determination of the safe service time of the production string according to the equivalent stress and the yield strength corresponding to the production string comprises: if the equivalent stress is less than the yield strength, re-executing the step of calculating the equivalent stress corresponding to the corrosion core position by calculating the total radial stress, the total circumferential stress and the total axial stress corresponding to the corrosion core position, wherein each of the steps of calculating the equivalent stress corresponding to the corrosion core position is separated by a unit interval time.

[0008] In one embodiment of the present application, based on the foregoing scheme, the method further comprises: if the equivalent stress is greater than the yield strength, calculating the safe service time of the production string based on the unit interval time.

[0009] In one embodiment of the present application, based on the foregoing scheme, the total radial stress is calculated by the following formula:

[0010] σ i = σ r ′+ σ r ″

[0011] Wherein, σ i is the total radial stress suffered by the corrosion core position of the production string at the current time node, MPa; σ r ′ is the radial stress generated by the internal pressure and the external extrusion force at the corrosion core position of the production string at the current time node, MPa; σ r ″ is the radial stress generated by the heat at the corrosion core position of the production string at the current time node, MPa.

[0012] In one embodiment of the present application, based on the foregoing scheme, the total circumferential stress is calculated by the following formula:

[0013] σ θ = σ θ ′+ σ θ ″

[0014] Wherein, σ θ is the total circumferential stress suffered by the corrosion core position of the production string at the current time node, MPa; σ θ ′ is the circumferential stress generated by the internal pressure and the external extrusion force at the corrosion core position of the production string at the current time node, MPa; σ θ ″ is the circumferential stress generated by the heat at the corrosion core position of the production string at the current time node, MPa.

[0015] In one embodiment of the present application, based on the foregoing scheme, the total axial stress is calculated by the following formula:

[0016] σ z = σ zo + σ zb + σ z ′+ σ z ″

[0017] Wherein, σ z is the total axial stress suffered by the corrosion core position of the production string at the current time node, MPa; σ zoσ is the initial axial stress of the corrosion core position of the production string at the current time node due to the self-weight and the buoyancy, MPa; zb σ is the axial stress of the corrosion core position of the production string at the current time node due to the bending of the production string, MPa; z σ is the axial stress of the corrosion core position of the production string at the current time node due to the internal pressure and the external extrusion force, MPa; z σ is the axial stress of the corrosion core position of the production string at the current time node due to the heat, MPa.

[0018] In an embodiment of the present application, based on the foregoing scheme, the equivalent stress is calculated by the following formula:

[0019]

[0020] σ is the equivalent stress of the corrosion core position of the production string at the current time node, MPa. equ σ is the equivalent stress of the corrosion core position of the production string at the current time node, MPa. i σ is the total radial stress, MPa. θ σ is the total circumferential stress, MPa. z σ is the total axial stress, MPa.

[0021] According to an aspect of an embodiment of the present application, a device for determining the safe service time of a production string is provided, and the device comprises: a judging unit configured to determine a corrosion core position according to the injection-production condition of an injection-production well, the corrosion core position being a position corresponding to the maximum gas partial pressure of the production string; a first calculating unit configured to calculate the equivalent stress of the corrosion core position by calculating the total radial stress, the total circumferential stress and the total axial stress of the corrosion core position; and a second calculating unit configured to determine the safe service time of the production string according to the equivalent stress and the yield strength corresponding to the production string.

[0022] According to an aspect of an embodiment of the present application, a computer readable storage medium having a computer program stored thereon is provided, and the computer program comprises executable instructions, when the executable instructions are executed by a processor, the method described in the above embodiments is implemented.

[0023] According to an aspect of an embodiment of the present application, an electronic device is provided, and the electronic device comprises: one or more processors; and a memory configured to store executable instructions of the processors, when the executable instructions are executed by the one or more processors, the one or more processors implement the method described in the above embodiments.

[0024] In the technical solution of the embodiment of the present application, first, the corrosion core position corresponding to the production pipe string is obtained by analyzing the gas pressure conditions of each position of the production pipe string in the injection-production working condition, wherein the corrosion core position is the position corresponding to the maximum gas partial pressure of the production pipe string. According to the corrosion core position, the total radial stress, the total circumferential stress and the total axial stress corresponding to the corrosion core position are calculated, so that the equivalent stress corresponding to the corrosion core position is calculated. By judging the equivalent stress corresponding to the corrosion core position of the current production pipe string and the yield strength of the current production pipe string, the safe service time of the production pipe string can be determined.

[0025] Therefore, the production pipe string safe service time determination method based on the present application can improve the accuracy of calculating the safe service time of the production pipe string, and can provide a basis for wellbore integrity and safe operation and maintenance of injection-production wells.

[0026] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present application. BRIEF DESCRIPTION OF DRAWINGS

[0027] The drawings incorporated into the specification and forming a part thereof, illustrate embodiments consistent with the present application and, together with the specification, serve to explain the principles of the present application. It is apparent that the drawings described below are only some embodiments of the present application, and other drawings can be obtained from these drawings without creative labor for those skilled in the art. In the drawings:

[0028] Figure 1 is a flow chart of the production pipe string safe service time determination method according to the embodiment of the present application;

[0029] Figure 2 is a block diagram of the production pipe string safe service time determination device according to the embodiment of the present application;

[0030] Figure 3 is a schematic diagram of the system structure of the electronic device according to the embodiment of the present application. DETAILED DESCRIPTION

[0031] Example implementations will now be described more fully with reference to the accompanying drawings. Example implementations may, however, be implemented in many different forms and should not be construed as limited to the examples set forth herein; rather, these implementations are provided so that this disclosure will be thorough and complete, and will fully convey the gist of the example implementations to those skilled in the art. Like reference numerals refer to like elements throughout.

[0032] Moreover, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of embodiments of the application. One skilled in the relevant art will recognize, however, that the application can be practiced without one or more of the specific details, or with other methods, components, materials, and so forth. In other instances, well-known structures, devices, implementations, and operations have not been shown or described in detail to avoid obscuring aspects of the application.

[0033] The block diagrams in the drawings show only the functionality of the features and can not imply that the functionality must be implemented in a specific manner. For example, the functionality can 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.

[0034] The flow diagrams shown in the drawings are only exemplary and do not necessarily include all of the content and operations / steps, nor must the operations / steps be performed in the order shown. For example, some operations / steps can be performed in a different order, or some operations / steps can be combined or partially combined, so the actual order of execution can be changed according to actual conditions.

[0035] It should be noted that "multiple" referred to herein means two or more. The association relationship of "and / or" describes the associated objects, which means that there can be three relationships, for example, A and / or B can mean that A exists alone, A and B exist together, and B exists alone. The character " / " generally represents that the associated objects before and after are in an "or" relationship.

[0036] The implementation details of the technical solutions of the embodiments of the application are described in detail as follows:

[0037] According to an aspect of the application, a production string safe service time determination method is provided, Figure 1 For the flowchart of the production string safe service time determination method shown in the embodiments of the application, the production string safe service time determination method can be executed by a device with computing processing function, and the production string safe service time determination method at least includes steps 110 to 130, which are described in detail as follows:

[0038] In step 110, according to the injection-production working condition of the injection-production well, the corrosion core position is determined, and the corrosion core position is the position corresponding to the maximum gas partial pressure of the production string.

[0039] In the present application, wellbore integrity is a prerequisite for ensuring safe and smooth production of oil and gas. If the casing of an injection-production well is damaged or changed due to external formation environment or internal injection-production working condition factors, the wellbore integrity will be damaged, thereby affecting the operation of the injection-production well, and even causing a major safety accident. Therefore, by analyzing the corrosion core position of the production string, the corrosion degree of the current production string can be determined, so that the safe service time of the production string can be determined.

[0040] With reference to the foregoing Figure 1 In step 120, the equivalent stress corresponding to the corrosion core position is calculated by calculating the total radial stress, the total circumferential stress and the total axial stress corresponding to the corrosion core position.

[0041] In the present application, in the injection-production working condition, the production string will be affected by stress in different directions, thereby causing perforation and rupture of the production string, and further shortening the safe service time of the production string. In order to accurately calculate the safe service time of the production string, the total radial stress, the total circumferential stress and the total axial stress corresponding to the corrosion core position can be calculated at different time nodes of the injection-production working condition, so as to calculate the equivalent stress corresponding to the corrosion core position, and further determine the safe service time of the production string.

[0042] Specifically, the total radial stress is calculated by the following formula:

[0043] σ i r r ′+σ r ″

[0044] Wherein, σ i r is the total radial stress of the corrosion core position of the production string at the current time node, MPa; σ r ′ is the radial stress of the corrosion core position of the production string at the current time node due to internal pressure and external extrusion force, MPa; σ r ″ is the radial stress of the corrosion core position of the production string at the current time node due to thermal action, MPa.

[0045] Further, the radial stress of the above-mentioned corrosion core position of the production string at the current time node due to internal pressure and external extrusion force (i.e. σ r ′) can be calculated by the following formula:

[0046]

[0047] Wherein, P i e is the external extrusion force of the corrosion core position of the production string at the current time node, MPa; P o is the internal pressure of the corrosion core position of the production string at the current time node, MPa; rci r represents the inner radius of the production tubing at the current time point, where the core corrosion location is located; co denoted as , where is the outer radius of the production tubing at the current time point where the corrosion core is located; denoted as r, where is the average inner and outer radii of the production tubing at the current time point where the corrosion core is located; denoted as r, in mm.

[0048] Furthermore, when calculating based on the inner and outer radii of the production tubing, the degree of corrosion of the tubing is constantly changing. Therefore, to accurately determine the safe service life of the production tubing, it is necessary to calculate the inner and outer radii in real time. Simultaneously, the calculation of the inner and outer radii needs to be based on the corrosion rate of the production tubing under different materials.

[0049] For example, when the production tubing material is N80, the corrosion rate of the production tubing in the H2S / CO2 / O2 three-phase gas can be calculated using the following formula:

[0050] V corr =-7.59+0.258T-0.496H2S-0.173CO2+14.501O2-0.0017T 2 +30.055O2 2 (1)

[0051] V corr =-7.59+0.258T-0.496H2S-0.173CO2+14.501O2-0.0017T 2 +30.055O2 2 (2)

[0052] In formula (1), V corr The corrosion rate of the production tubing at 50℃~100℃ is given in mm / year; in formula (2), V corr The corrosion rate of the production tubing at 100℃~240℃ is expressed in mm / year; T is the gas temperature when the production tubing comes into contact with the gas, in ℃.

[0053] For example, when the production tubing material is P110, the corrosion rate of the production tubing in the H2S / CO2 / O2 three-phase gas can be calculated using the following formula:

[0054] V corr =-6.231+0.216T-0.728H2S-0.075CO2+11.341O2-0.00143T 2 -16.617O2 2 (3)

[0055] V corr = -5.68 + 0.198T - 0.843H2S - 0.081CO2+ 10.174O2- 0.00133T 2 - 12.307O2 2 (5)

[0056] wherein, in formula (5), V corr is the corrosion rate of the production string under the condition of 50°C to 100°C, mm / year; in formula (6), V corr is the corrosion rate of the production string under the condition of 100°C to 240°C, mm / year; T is the gas temperature when the production string contacts the gas, °C.

[0057] For example, when the production string material is 110H, the corrosion rate of the production string in H2S / CO2 / O2 three-phase gas can be calculated by the following formula:

[0058] V corr = -5.68 + 0.198T - 0.843H2S - 0.081CO2+ 10.174O2- 0.00133T 2 - 12.307O2 2 (5)

[0059] V corr = 4.12 - 0.059T + 0.654H2S + 0.169CO2- 3.12O2+ 0.0002T 2 + 27.985O2 2 (6)

[0060] wherein, in formula (5), V corr is the corrosion rate of the production string under the condition of 50°C to 100°C, mm / year; in formula (6), V corr is the corrosion rate of the production string under the condition of 100°C to 240°C, mm / year; T is the gas temperature when the production string contacts the gas, °C.

[0061] For example, when the production string material is 110H, the corrosion rate of the production string in H2S / CO2 / O2 three-phase gas can be calculated by the following formula:

[0062] V corr = -5.585 + 0.18T - 0.689H2S + 0.076CO2+ 10.374O2- 0.0012T 2 - 12.753O2 2 (7)

[0063] V corr= 2.17 - 0.034T + 0.8H2S + 0.155CO2+ 1.364O2+ 0.000118T 2 + 13.495O2 2 (8)

[0064] wherein, in formula (7), V corr is the corrosion rate of the production string under the condition of 50-100℃, mm / year; in formula (8), V corr is the corrosion rate of the production string under the condition of 100-240℃, mm / year; T is the gas temperature when the production string contacts with the gas, ℃.

[0065] Further, the radial stress (i.e. σ r ″) of the above-mentioned corrosion core position of the production string at the current time node due to the thermal effect can be calculated by the following formula:

[0066]

[0067] wherein, α c is the linear thermal expansion coefficient of the production string at the current time node, m / (m·℃); E c is the elastic modulus of the production string at the current time node, MPa; u c is the Poisson's ratio of the production string at the current time node; ΔT is the change of the temperature of the corrosion core position of the production string at the current time node from the initial node temperature, ℃.

[0068] The total circumferential stress can be calculated by the following formula:

[0069] σ θ = σ θ ′+ σ θ ″

[0070] wherein, σ θ is the total circumferential stress of the corrosion core position of the production string at the current time node, MPa; σ θ ′ is the circumferential stress of the corrosion core position of the production string at the current time node due to the internal pressure and the external extrusion force, MPa; σ θ ″ is the circumferential stress of the corrosion core position of the production string at the current time node due to the thermal effect, MPa.

[0071] Further, the circumferential stress (i.e. σ θ ′) of the above-mentioned corrosion core position of the production string at the current time node due to the internal pressure and the external extrusion force can be calculated by the following formula:

[0072]

[0073] wherein P i is the external extrusion force of the corrosion core position of the production string at the current time node, MPa; P o is the internal pressure of the corrosion core position of the production string at the current time node, MPa; r ci is the inner radius of the production string at the corrosion core position of the production string at the current time node, mm; r co is the outer radius of the production string at the corrosion core position of the production string at the current time node, mm; r is the average of the inner and outer radii of the production string at the corrosion core position of the production string at the current time node, mm.

[0074] Further, the circumferential stress (i.e., σ θ ) of the corrosion core position of the production string at the current time node due to thermal action can be calculated by the following formula:

[0075]

[0076] wherein a c is the linear thermal expansion coefficient of the production string at the current time node, m / (m·℃); E c is the elastic modulus of the production string at the current time node, MPa; u c is the Poisson's ratio of the production string at the current time node; and ΔT is the change in temperature of the corrosion core position of the production string at the current time node from the initial time node, ℃.

[0077] The total axial stress is calculated by the following formula:

[0078] σ z = σ zo + σ zb + σ z ′ + σ z ″

[0079] wherein σ z is the total axial stress of the corrosion core position of the production string at the current time node, MPa; σ zo is the initial axial stress of the corrosion core position of the production string at the current time node due to the weight and the buoyancy, MPa; σ zb is the axial stress of the corrosion core position of the production string at the current time node due to the bending of the string, MPa; σ z ′ is the axial stress of the corrosion core position of the production string at the current time node due to the internal pressure and the external extrusion force, MPa; and σ z ″ is the axial stress of the corrosion core position of the production string at the current time node due to thermal action, MPa.

[0080] Further, the initial axial stress (i.e. σ zo ) of the above-mentioned corrosion core position of the production string at the current time node due to the self-weight and the buoyancy can be calculated by the following formula:

[0081] σ zo =(ρ c l c -ρ l l l )g·10 -6

[0082] wherein ρ c is the density of the production string, kg / m 3 ; ρ l is the average density of the three-phase gas in the annulus, kg / m 3 ; l c is the length of the production string from the corrosion core position to the bottom of the well, m; l l is the length of the string from the annulus gas to the bottom of the well, m; and g is the acceleration of gravity, taken as 9.8 N / kg.

[0083] Further, the axial stress (i.e. σ zb ) of the above-mentioned corrosion core position of the production string at the current time node due to the bending of the string can be calculated by the following formula:

[0084] σ zb =0.060156D leg d is

[0085] wherein D leg is the bending degree at the corrosion core position of the production string, ° / 30 m; and d is is the inner diameter of the production string, mm.

[0086] Further, the axial stress (i.e. σ z ′) of the above-mentioned corrosion core position of the production string at the current time node due to the internal pressure and the external extrusion force can be calculated by the following formula:

[0087] σ z ′=u c (σ r ′+σ θ ′)

[0088] wherein σ r ′ is the radial stress of the corrosion core position of the production string at the current time node due to the internal pressure and the external extrusion force, MPa; σ θ ′ is the circumferential stress of the corrosion core position of the production string at the current time node due to the internal pressure and the external extrusion force, MPa; and u cThis represents the Poisson's ratio of the production string at the current time point.

[0089] Furthermore, the axial stress (i.e., σ) generated by thermal action at the core corrosion location of the aforementioned production tubing at the current time point... z The result (") can be calculated using the following formula:

[0090]

[0091] Where, α c E represents the linear thermal expansion coefficient of the production tubing at the current time point, in m / (m·℃). c The elastic modulus of the production tubing at the current time point, in MPa; u c ΔT represents the Poisson's ratio of the production tubing at the current time point; ΔT represents the change in temperature at the corrosion core location of the production tubing at the current time point compared to the initial temperature, in °C.

[0092] The equivalent stress is calculated using the following formula:

[0093]

[0094] Where, σ equ The equivalent stress, in MPa, is the stress at the core corrosion location of the production tubing at the current time point; σ. i The total radial stress is given in MPa; σ is the total radial stress. θ The total circumferential stress is expressed in MPa; σ z For the total axial stress, MPa.

[0095] Continue to refer to Figure 1 In step 130, the safe service time of the production tubing is determined based on the equivalent stress and the yield strength corresponding to the production tubing.

[0096] In this application, after calculating the equivalent stress corresponding to the corrosion core location, and combining it with the yield strength corresponding to the production tubing, the safe service time of the production tubing is determined.

[0097] In one embodiment of this application, determining the safe service time of the production tubing based on the equivalent stress and the yield strength corresponding to the production tubing specifically includes step 131:

[0098] Step 131: If the equivalent stress is less than the yield strength, then the step of calculating the equivalent stress corresponding to the corrosion core location by calculating the total radial stress, total circumferential stress and total axial stress corresponding to the corrosion core location is repeated, wherein the time nodes corresponding to each step of calculating the equivalent stress corresponding to the corrosion core location are separated by a unit time interval.

[0099] In the embodiment, after the equivalent stress is obtained, the yield strength corresponding to the production string is acquired. If the equivalent stress is less than the yield strength, it indicates that, at the current time node and due to the influence of the gas corrosion on the equivalent stress and the yield strength corresponding to the production string, the current production string can guarantee the normal operation of the injection-production working condition. Therefore, the step of calculating the equivalent stress corresponding to the corrosion core position by calculating the total radial stress, the total circumferential stress and the total axial stress of the corrosion core position is re-executed to accurately calculate the safe service time of the production string. The time nodes corresponding to the above steps of calculating the total radial stress, the total circumferential stress, the total axial stress and the equivalent stress are separated by a unit interval time. The smaller the value of the unit interval time is, the more accurate the calculated safe service time of the production string is.

[0100] In an embodiment of the present application, after the equivalent stress is obtained, the step 132 specifically further includes:

[0101] In step 132, if the equivalent stress is greater than the yield strength, the safe service time of the production string is calculated based on the unit interval time.

[0102] In the embodiment, after the equivalent stress is obtained, the yield strength corresponding to the production string is acquired. If the equivalent stress is greater than the yield strength, it indicates that, at the current time node and due to the influence of the gas corrosion on the equivalent stress and the yield strength corresponding to the production string, casing damage and casing deformation occur in the current production string, which destroys the wellbore integrity and thus affects the normal operation of the injection-production working condition. Therefore, the safe service time of the production string can be determined based on the initial time node (i.e., the time node corresponding to the first step of calculating the equivalent stress corresponding to the corrosion core position by calculating the total radial stress, the total circumferential stress and the total axial stress of the corrosion core position), the current time node and the unit interval time.

[0103] In summary, the above method can improve the accuracy of calculating the safe service time of the production string and can provide a basis for the wellbore integrity and the safe operation and maintenance of the injection-production well.

[0104] The device embodiment of the present application is described below, which can be used to execute the production string safe service time determination method in the above embodiments of the present application. For details not disclosed in the device embodiment of the present application, please refer to the above embodiments of the production string safe service time determination method of the present application.

[0105] Figure 2 The block diagram of the production string safe service time determination device according to the embodiment of the present application is shown.

[0106] Referring toFigure 2 As shown, the production string safe service time determination apparatus 200 according to one embodiment of the present application comprises: a judging unit configured to determine a corrosion core position according to injection-production conditions of an injection-production well, the corrosion core position being a position corresponding to maximum gas partial pressure of a production string; a first calculating unit configured to calculate equivalent stress corresponding to the corrosion core position by calculating total radial stress, total circumferential stress and total axial stress corresponding to the corrosion core position; and a second calculating unit configured to determine safe service time of the production string according to the equivalent stress and yield strength corresponding to the production string.

[0107] As another aspect, the present application also provides a computer readable storage medium having stored thereon a program product capable of implementing the method described above. In some possible implementation manners, various aspects of the present application can also be implemented in the form of a program product, which includes program codes for causing terminal equipment to perform steps according to various exemplary embodiments of the present application described in the above “Exemplary Method” section when the program product runs on the terminal equipment.

[0108] The computer readable signal medium can include a data signal propagated in baseband or propagated as a carrier wave in a propagated data signal, in which the propagated data signal has a format that includes program code readable by a machine for performing an operational aspect of the present application. The computer readable medium also can be any medium that can be read by a machine, in which the medium includes instructions that cause a machine to perform a method according to the present application.

[0109] The program code included on the computer readable medium can be implemented in any suitable programming language, including but not limited to C, C++, Java, or any other suitable programming language. The program code can be executed by a processor of a computer, a server, a mobile device, or any other suitable processing device.

[0110] The program code can be executed by one or more programmable processors, which can be hardware, software, firmware, or any combination thereof. The program code can be written in any combination of one or more programming languages, including an object oriented programming language such as Java, C++, or the like, and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code can execute entirely on a user's computing device, partly on the user's computing device, as a stand-alone software package, partly on the user's computing device and partly on a remote computing device or entirely on the remote computing device or server. In the latter scenario, the remote computing device can be connected to the user's computing device through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to an external computing device, such as through the Internet using an Internet service provider.

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

[0112] Those skilled in the art can understand that various aspects of the present application can be implemented as a system, a method or a program product. Therefore, various aspects of the present application can be embodied as a whole hardware embodiment, a whole software embodiment (including firmware, microcode, etc.), or an embodiment combining hardware and software aspects, which can be collectively referred to as "circuitry", "module" or "system" herein.

[0113] Figure 3 For the schematic diagram of the system structure of the electronic device shown in the embodiments of the present application, the electronic device 300 according to this embodiment of the present application is described below with reference to Figure 3 Figure 3 The electronic device 300 shown is merely an example and should not impose any limitation on the functions and use range of the embodiments of the present application.

[0114] As shown in Figure 3 The electronic device 300 is in the form of a general computing device. The components of the electronic device 300 can include, but are not limited to, the at least one processing unit 310 described above, the at least one storage unit 320 described above, 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 performs the steps according to various exemplary embodiments of the present application described in the "Embodiment Method" part of the present specification.

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

[0117] The storage unit 320 can further include program / utility 324 having a set of (at least one) 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 thereof can include implementation of a network environment.

[0118] The bus 330 can represent one or more of several types of bus structures, including a storage unit bus or storage unit controller, a peripheral bus, a graphics acceleration port, a processing unit bus, or a local bus using any of a variety of bus architectures. ​

[0119] The electronic device 300 can also communicate with one or more external devices 1200 such as a keyboard, a pointing device, a Bluetooth device, etc.; and can communicate with one or more devices that enable a user to interact with the electronic device 300 and / or one or more devices (e.g. routers, modems, etc.) that enable the electronic device 300 to communicate with one or more other computing devices. Such communication can occur via Input / Output (I / O) interface 350. Also, the electronic device 300 can communicate with one or more networks such as a local area network (LAN), a wide area network (WAN), and / or the public network, e.g. the Internet, via network adapter 360. As depicted, network adapter 360 communicates with the other components of the electronic device 300 via bus 330. It should be appreciated that although not shown, other hardware and / or software modules could be used in connection with the electronic device 300. These include, but are not limited to, microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data archival storage systems, etc.

[0120] Those skilled in the art will readily understand that the example embodiments described herein can be implemented by software and / or by software in combination with the requisite hardware. Thus, the technical solutions according to the embodiments 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 disk, a mobile hard disk, etc.) or a network, and includes a number of 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 methods according to the embodiments of the present application.

[0121] In addition, the above-described flowcharts are only schematic descriptions of the processes included in the methods according to the exemplary embodiments of the present application, and are not intended to be limiting. It will be readily understood that the processes shown in the above-described flowcharts do not indicate or limit the time sequence of the processes. In addition, it will be readily understood that the processes can be executed synchronously or asynchronously, for example, in multiple modules.

[0122] It should be understood that the present application is not limited to the precise construction that has been described above and illustrated in the accompanying drawings, and that various modifications and changes can be made by those skilled in the art without departing from the scope of the present application. The scope of the present application is limited only by the appended claims.

Claims

1. A method for determining the safe service life of a production tubing string, characterized in that, The method includes: Based on the injection and production conditions of the injection and production well, the location of the corrosion core is determined, which is the location corresponding to the maximum gas partial pressure of the production tubing. The equivalent stress corresponding to the corrosion core location is calculated by calculating the total radial stress, total circumferential stress, and total axial stress at the corrosion core location. If the equivalent stress is less than the yield strength, then the step of calculating the equivalent stress corresponding to the corrosion core location by calculating the total radial stress, total circumferential stress and total axial stress corresponding to the corrosion core location is repeated, wherein the time nodes corresponding to each step of calculating the equivalent stress corresponding to the corrosion core location are separated by a unit time interval. If the equivalent stress is greater than the yield strength, then the safe service time of the production tubing is calculated based on the unit interval time. The total radial stress is calculated using the following formula: ； ； ； in, The total radial stress, in MPa, is the stress at the core corrosion location of the production tubing at the current time point. The radial stress (MPa) at the core corrosion location of the production tubing due to internal pressure and external extrusion at the current time point; The radial stress (MPa) at the core corrosion location of the production tubing due to thermal effects at the current time point; The external extrusion force at the core corrosion location of the production tubing at the current time point, in MPa; The internal pressure (MPa) at the core corrosion location of the production tubing at the current time point; The inner radius of the production tubing at the current time point, in mm, represents the core location of corrosion in the production tubing. The outer radius of the production tubing at the current time point, in mm, represents the core location of corrosion in the production tubing. The value in mm represents the average inner and outer radii of the production tubing at the current time point, indicating the location of the core corrosion site. The linear thermal expansion coefficient of the production tubing at the current time point is given in m / (m·℃). The elastic modulus of the production tubing at the current time point, in MPa; The Poisson's ratio of the production string at the current time point; The change in temperature at the core corrosion location of the production tubing at the current time point compared to the initial node temperature, expressed in °C. The total circumferential stress is calculated using the following formula: ； ； ； in, The total circumferential stress, in MPa, is the stress at the core corrosion location of the production tubing at the current time point. The circumferential stress (MPa) at the core corrosion location of the production tubing due to internal pressure and external extrusion at the current time point; The circumferential stress (MPa) at the core corrosion location of the production tubing due to thermal effects at the current time point; The total axial stress is calculated using the following formula: ； ； ； in, The total axial stress, in MPa, is the stress at the core corrosion location of the production tubing at the current time point. The initial axial stress (MPa) at the core corrosion location of the production tubing due to its own weight and buoyancy at the current time point; The axial stress (MPa) at the core corrosion location of the production tubing due to tubing bending at the current time point; The axial stress (MPa) at the core corrosion location of the production tubing due to internal pressure and external extrusion at the current time point; The axial stress (MPa) at the core corrosion location of the production tubing due to thermal effects at the current time point; The density of the production tubing is measured in kg / m³. 3 ; The average density of the three-phase gas in the annulus, kg / m³ 3 ; The length of the production tubing from the core of the corrosion zone to the bottom of the well, in meters; The length of the tubing from the annular gas to the bottom of the well, in meters (m). The acceleration due to gravity is taken as 9.8 N / kg; The curvature at the core corrosion location of the production tubing is measured in ° / 30m. The inner diameter of the production tubing body, in mm; The equivalent stress is calculated using the following formula: ； in, The equivalent stress, in MPa, is the stress experienced at the core corrosion location of the production tubing at the current time point. The total radial stress is expressed in MPa. The total circumferential stress is expressed in MPa. For the total axial stress, MPa.

2. A device for determining the safe service time of a production tubing string, characterized in that, The device includes: The judgment unit is used to determine the location of the corrosion core based on the injection and production conditions of the injection and production well. The location of the corrosion core is the location corresponding to the maximum gas partial pressure of the production tubing. The first calculation unit is used to calculate the equivalent stress corresponding to the corrosion core location by calculating the total radial stress, total circumferential stress and total axial stress corresponding to the corrosion core location; The second calculation unit is used to, if the equivalent stress is less than the yield strength, re-execute the step of calculating the equivalent stress corresponding to the corrosion core location by calculating the total radial stress, total circumferential stress, and total axial stress corresponding to the corrosion core location, wherein the time nodes corresponding to each step of calculating the equivalent stress corresponding to the corrosion core location are separated by a unit interval time; if the equivalent stress is greater than the yield strength, calculate the safe service time of the production tubing based on the unit interval time; The total radial stress is calculated using the following formula: ； ； ； in, The total radial stress, in MPa, is the stress at the core corrosion location of the production tubing at the current time point. The radial stress (MPa) at the core corrosion location of the production tubing due to internal pressure and external extrusion at the current time point; The radial stress (MPa) at the core corrosion location of the production tubing due to thermal effects at the current time point; The external extrusion force at the core corrosion location of the production tubing at the current time point, in MPa; The internal pressure (MPa) at the core corrosion location of the production tubing at the current time point; The inner radius of the production tubing at the current time point, in mm, represents the core location of corrosion in the production tubing. The outer radius of the production tubing at the current time point, in mm, represents the core location of corrosion in the production tubing. The value in mm represents the average inner and outer radii of the production tubing at the current time point, indicating the location of the core corrosion site. The linear thermal expansion coefficient of the production tubing at the current time point is given in m / (m·℃). The elastic modulus of the production tubing at the current time point, in MPa; The Poisson's ratio of the production string at the current time point; The change in temperature at the core corrosion location of the production tubing at the current time point compared to the initial node temperature, expressed in °C. The total circumferential stress is calculated using the following formula: ； ； ； in, The total circumferential stress, in MPa, is the stress at the core corrosion location of the production tubing at the current time point. The circumferential stress (MPa) at the core corrosion location of the production tubing due to internal pressure and external extrusion at the current time point; The circumferential stress (MPa) at the core corrosion location of the production tubing due to thermal effects at the current time point; The total axial stress is calculated using the following formula: ； ； ； in, The total axial stress, in MPa, is the stress at the core corrosion location of the production tubing at the current time point. The initial axial stress (MPa) at the core corrosion location of the production tubing due to its own weight and buoyancy at the current time point; The axial stress (MPa) at the core corrosion location of the production tubing due to tubing bending at the current time point; The axial stress (MPa) at the core corrosion location of the production tubing due to internal pressure and external extrusion at the current time point; The axial stress (MPa) at the core corrosion location of the production tubing due to thermal effects at the current time point; The density of the production tubing is measured in kg / m³. 3 ; The average density of the three-phase gas in the annulus, kg / m³ 3 ; The length of the production tubing from the core of the corrosion zone to the bottom of the well, in meters; The length of the tubing from the annular gas to the bottom of the well, in meters (m). The acceleration due to gravity is taken as 9.8 N / kg; The curvature at the core corrosion location of the production tubing is measured in ° / 30m. The inner diameter of the production tubing body, in mm; The equivalent stress is calculated using the following formula: ； in, The equivalent stress, in MPa, is the stress experienced at the core corrosion location of the production tubing at the current time point. The total radial stress is expressed in MPa. The total circumferential stress is expressed in MPa. For the total axial stress, MPa.

3. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores at least one piece of program code, which is loaded and executed by a processor to perform the operations described in claim 1.

4. An electronic device, characterized in that, The electronic device includes one or more processors and one or more memories, wherein at least one piece of program code is stored in the one or more memories, and the at least one piece of program code is loaded and executed by the one or more processors to perform the operation performed by the method as described in claim 1.

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