Shaft blockage position detection method

Abstract

The invention provides a shaft blockage position detection method which comprises the following steps: determining the leakage depth and collapse depth of a production pipe column after the leakage and collapse of the production pipe column are judged; dividing the production pipe column into a plurality of first sub-production pipe columns; the dynamic pressure in the first sub-production pipe column is calculated; the pressure, corresponding to the production pipe column, of the throttled production pipe column and the temperature, corresponding to the production pipe column, of the throttled production pipe column are determined; according to the pressure of the production pipe column after throttling and the temperature of the production pipe column after throttling, the blocking position and wellhead calculation pressure of the corresponding production pipe column are determined; judging whether the production pipe column meets collapse conditions or not according to the dynamic internal pressure of the first sub-production pipe column and the calculated pressure of the wellhead; and if it is judged that the production pipe column meets the collapse condition, the blockage position of the production pipe column is output, so that the wellbore blockage position can be detected, and the blockage condition of the wellbore blockage position can be determined.

Description

Technical Field

[0001] The present application relates to the technical field of natural gas extraction, and in particular to a method for detecting a wellbore blockage position. Background Art

[0002] Wellbores are widely used in natural gas development and underground storage, compressed air energy storage, and underground hydrogen storage. They are an important support for the efficient use of clean energy. Wellbores are used to transmit gas from underground gas reservoirs to the ground. However, wellbores are prone to blockage during the production process, causing damage to the internal structure of the wellbores, which in turn affects the normal operation of the wellbores.

[0003] However, there is no effective detection method for determining the wellbore blockage position at present. Therefore, a wellbore blockage position detection method is urgently needed to determine the blockage situation of the wellbore blockage position. Summary of the invention

[0004] The present application provides a method for detecting a wellbore blockage position to solve the problem that there is currently no effective detection method for determining the wellbore blockage position.

[0005] In a first aspect, the present application provides a method for detecting a wellbore blockage position, which is applied to a computer device, comprising:

[0006] Acquiring initial operating parameters of the wellbore, and judging whether the production tubing in the wellbore is leaking or crushed according to the initial operating parameters;

[0007] If it is determined that the production tubing string is leaking or crushed, then the shutdown parameter of the wellbore is obtained, and the leakage depth of the production tubing string is determined according to the shutdown parameter;

[0008] Determine the collapse depth of the production string according to a preset logging method;

[0009] Dividing the portion from the bottom of the production string to the collapse depth into a plurality of first sub-production strings according to a first preset length;

[0010] Acquiring operating parameters of the wellbore, and calculating the pressure in each first sub-production string according to the operating parameters, wherein the inner diameter of the production string affects the pressure in each first sub-production string;

[0011] Dividing the inner diameter of the production tubing into a plurality of sizes to be adjusted according to a preset ratio;

[0012] The inner diameter of the production string is adjusted from large to small according to a plurality of sizes to be adjusted, so as to generate a corresponding dynamic pressure in the first sub-production string;

[0013] According to the leakage depth, the collapse depth and the bottom hole depth, the numbers corresponding to the first sub-production tubing string are determined to be the first number, the second number and the third number respectively;

[0014] Determining a throttled production string pressure and a throttled production string temperature corresponding to the production string;

[0015] Determine the pressure of the production tubing string after throttling as the pressure at the blockage point of the production tubing string, and determine the temperature of the production tubing string after throttling as the temperature at the blockage point of the production tubing string;

[0016] Determine a plugging position of a corresponding production string according to the production string pressure after throttling and the production string temperature after throttling, wherein the plugging position is between the first number and the second number;

[0017] Determine the wellhead calculated pressure according to the pressure at the blockage point of the production tubing string, the temperature at the blockage point of the production tubing string and the third number;

[0018] Determining whether the production string meets the collapse condition according to the dynamic pressure in the first sub-production string and the wellhead calculated pressure;

[0019] If it is determined that the production tubing string meets the collapse condition, the blockage position of the production tubing string is output.

[0020] In a possible design, the calculation formula for dividing the inner diameter of the production string into a plurality of sizes to be adjusted according to a preset ratio includes:

[0021]

[0022] Where, d max The maximum inner diameter of the production string; d tn is the inner diameter of the production string; △d is the preset ratio; d min The minimum size of the inner diameter of the production string;

[0023] Accordingly, the calculation formula for determining the numbers of the first sub-production tubing strings as the first number, the second number, and the third number respectively according to the leakage depth, the collapse depth, and the bottom hole depth includes:

[0024]

[0025] Where M is the first number, a dimensionless integer; h LL is the leakage depth, m; N is the second number, a dimensionless integer; h cc is the collapse depth, m; X is the third number, a dimensionless integer; h w is the bottom depth of the well; H fd1is a first preset length;

[0026] Correspondingly, the calculation formula for determining the blockage position of the corresponding production string according to the production string pressure after throttling and the production string temperature after throttling includes:

[0027]

[0028] In the formula, is the temperature corresponding to the plugging position of the production string; Y is the number of the first sub-production string corresponding to the plugging position; is the temperature of the production string after throttling; The pressure corresponding to the blockage position of the production string; is the production string pressure after throttling.

[0029] In a possible design, the step of obtaining the shutdown parameters of the wellbore and determining the leakage depth of the production string according to the shutdown parameters includes: obtaining the shutdown parameters of the wellbore, wherein the shutdown parameters include at least the initial annular pressure of the casing annulus, annular gas density, gas depth of the casing annulus, annular liquid density, annular liquid depth, surface temperature, geothermal gradient, standard pressure, standard temperature and standard gas density; determining the annular pressure of the casing annulus at different depths according to the initial annular pressure, the annular gas density, the gas depth, the annular liquid density and the annular liquid depth; and dividing the wellbore into the production string according to a second preset length. The production string is divided into a plurality of second sub-production strings; the temperature of each second sub-production string is calculated according to the surface temperature, the geothermal gradient and the second preset length; the gas density in the initial second sub-production string is calculated according to the temperature of each second sub-production string, the initial pressure in the second sub-production string, the standard pressure, the standard temperature and the standard density of the gas; the pressure in each second sub-production string is calculated according to the gas density of the initial second sub-production string and the second preset length; the leakage depth of the production string is determined according to the pressure in each second sub-production string and the annular pressure of the casing annulus at different depths.

[0030] In a possible design, the calculation formula for determining the annular pressure of the casing annulus at different depths according to the initial annular pressure, the annular gas density, the gas depth, the annular liquid density and the annular liquid depth includes:

[0031]

[0032] In the formula, p aL The depth is h L Annulus pressure of casing annulus, MPa; p an is the initial annular pressure, MPa; ρ gais the annular air density, kg / m 3 ; g is the acceleration due to gravity; ρ L is the density of the annular liquid, kg / m 3 ;h L is the gas depth, m; h g is the annulus liquid depth, m;

[0033] Accordingly, the step of calculating the temperature of each second sub-production string according to the surface temperature, the geothermal gradient and the second preset length includes:

[0034]

[0035] Where, T k is the temperature of the second sub-production string of the kth section, ℃; T0 is the surface temperature, ℃; g e is the geothermal gradient, ℃ / m; h fd2 is a second preset length;

[0036] Accordingly, the calculation formula for calculating the gas density in the initial second sub-production string according to the temperature of each second sub-production string, the initial pressure in the second sub-production string, the standard pressure, the standard temperature and the standard density of the gas includes:

[0037]

[0038] In the formula, is the gas density in the second sub-production string of section k, kg / m 3 First, it is necessary to determine the gas density in the initial second sub-production string; k is the pressure in the second sub-production string of the kth section, MPa, starting from the initial pressure in the second sub-production string; T s is the standard temperature, °C; p s is the standard pressure, MPa; T k is the temperature of the second sub-production column of the kth section, °C; ρ s is the standard density of the gas, kg / m 3 ;

[0039] Accordingly, the calculation formula for calculating the pressure in each second sub-production string according to the gas density of the initial second sub-production string and the second preset length includes:

[0040]

[0041] In the formula, p k+1 is the pressure in the second sub-production string of the k+1th section, MPa; p k is the pressure in the second sub-production string of section k, MPa; is the gas density in the second sub-production string of section k, kg / m 3 ; g is the acceleration due to gravity; h fd2 is the second preset length.

[0042] In a possible design, the step of obtaining the operating parameters of the wellbore and calculating the pressure in each first sub-production string according to the operating parameters includes: obtaining the operating parameters of the wellbore, wherein the operating parameters at least include dimensionless time, well opening production time, formation heat diffusion coefficient, wellbore radius, ratio of wellbore specific heat capacity to formation specific heat capacity, gas standard density, gas production rate, gas temperature in the production string, formation thermal conductivity, initial formation temperature, gas specific heat capacity in the production string, radial heat transfer thermal resistance, standard temperature, standard The dimensionless formation temperature is calculated according to the dimensionless time, the well opening production time, the formation heat diffusion coefficient, the wellbore radius, and the ratio of the specific heat capacity of the wellbore to the specific heat capacity of the formation; the gas mass flow rate in the production string is calculated according to the standard gas density and the gas production rate; the gas temperature in the first sub-production string of the previous section, the first preset length, the first preset length, the first preset length, the second preset length, the dimensionless formation temperature, the dimensionless formation temperature, the dimensionless formation temperature, the gas mass flow rate, the gas temperature in the first sub-production string of the previous section, the first preset length, the first preset length, the second preset length ... second preset length, the dimensionless formation temperature, the dimensionless formation temperature, the gas mass flow rate, the gas temperature in the first sub-production string of the previous section, the first preset length, the second preset length, the dimensionless formation temperature The gas temperature in the corresponding first sub-production string is calculated according to the formation thermal conductivity, the initial formation temperature corresponding to the first sub-production string, the specific heat capacity of the gas in the production string, and the radial heat transfer thermal resistance; the gas density in each first sub-production string is calculated according to the gas temperature in each first sub-production string, the pressure in each first sub-production string, the standard temperature, the standard pressure, and the standard density of the gas; the gas flow rate in each first sub-production string is calculated according to the gas density in each first sub-production string, the gas production rate, and the standard density of the gas; the friction coefficient of each first sub-production string is calculated according to the roughness of the production string, the gas viscosity in the production string, the inner diameter of the production string, the gas density in each first sub-production string, and the gas flow rate in each first sub-production string; the pressure in each first sub-production string is calculated according to the friction coefficient of each first sub-production string, the gas density in each first sub-production string, the first preset length, the inner diameter of the production string, and the gas flow rate in each first sub-production string.

[0043] In a possible design, the calculation formula for calculating the dimensionless formation temperature based on the dimensionless time, the well opening production time, the formation heat diffusion coefficient, the wellbore radius, and the ratio of the wellbore specific heat capacity to the formation specific heat capacity includes:

[0044]

[0045] Where, T Dis the dimensionless formation temperature, dimensionless; t D is dimensionless time, dimensionless; t is the well opening production time, s; α e is the formation heat diffusion coefficient, m 2 / s;r w is the borehole radius, m; ω is the ratio of the specific heat capacity of the wellbore to the specific heat capacity of the formation, dimensionless;

[0046] Accordingly, the calculation formula for calculating the gas mass flow rate in the production string according to the gas standard density and the gas production rate includes:

[0047]

[0048] In the formula, w f is the gas mass flow rate in the production column, kg / s; Q is the gas production rate, m 3 / d;ρ s is the standard density of the gas, kg / m 3 ;

[0049] Accordingly, the calculation formula for calculating the corresponding gas temperature in the first sub-production string according to the dimensionless formation temperature, the gas mass flow rate, the gas temperature in the previous first sub-production string, the first preset length, the formation thermal conductivity, the initial formation temperature corresponding to the first sub-production string, the gas specific heat capacity in the production string, and the radial heat transfer thermal resistance includes:

[0050]

[0051] Where, T f i is the gas temperature in the first sub-production column of the i-th section, °C; T D is the dimensionless formation temperature; T f i-1 is the gas temperature in the first sub-production string of the i-th section corresponding to the previous section, °C; h fd1 is the first preset length, m; λ e is the formation thermal conductivity, W / (m·℃); T e i The initial formation temperature corresponding to the first sub-production string of the i-th section, °C; w f is the gas mass flow rate in the production string, kg / s; C f is the specific heat capacity of the gas in the production column, J / (kg·℃); R to i is the radial heat transfer resistance of the i-th wellbore segment with length △z, m·℃ / W;

[0052] Accordingly, the calculation formula for calculating the gas density in each first sub-production string according to the gas temperature in each first sub-production string, the pressure in each first sub-production string, the standard temperature, the standard pressure and the standard density of the gas includes:

[0053]

[0054] In the formula, is the gas density in the first sub-production string of section i-1, kg / m 3 ; T f i-1 is the gas temperature in the first sub-production string corresponding to the i-1th section; P i-1 is the pressure in the first sub-production string of the i-1th section, MPa; T s is the standard temperature, °C; p s is the standard pressure, MPa; ρ s is the standard density of the gas, kg / m 3 ;

[0055] Accordingly, the calculation formula for calculating the gas flow rate in each first sub-production string according to the gas density in each first sub-production string, the gas production rate and the gas standard density includes:

[0056]

[0057] In the formula, is the gas flow rate in the first sub-production string of the i-1th section, m / s; Q is the gas production rate, m 3 / d;ρ s is the standard density of the gas, kg / m 3 ;d tn is the inner diameter of the production string, m; is the gas density in the first sub-production string of section i-1, kg / m 3 ;

[0058] Accordingly, the calculation formula for calculating the friction coefficient of each first sub-production string according to the roughness of the production string, the gas viscosity in the production string, the inner diameter of the production string, the gas density in each first sub-production string, and the gas flow rate in each first sub-production string includes:

[0059]

[0060] In the formula, f i-1 is the friction coefficient of the first sub-production string of the i-1th section, dimensionless; Ra is the roughness of the production string, m; μ is the gas viscosity in the production string, Pa·s; is the gas density in the first sub-production string of section i-1, kg / m 3 ; is the gas flow rate in the first sub-production string of the i-1th section, m / s; d tn i is the inner diameter of the first sub-production string of the i-th section, m;

[0061] Accordingly, the calculation formula for calculating the pressure in each first sub-production string according to the friction coefficient of each first sub-production string, the gas density in each first sub-production string, the first preset length, the inner diameter of the production string, and the gas flow rate in each first sub-production string includes:

[0062]

[0063] In the formula, is the pressure in the first sub-production string corresponding to the i-th section; is the pressure in the first sub-production string corresponding to the i-1th section; h fd1 is the first preset length, m; Gas density in the first sub-production string of section i-1, kg / m 3 ;f i-1 is the friction coefficient of the first sub-production string of the i-1th section, dimensionless; is the gas flow rate in the first sub-production string of the i-1th section, m / s; d tn is the inner diameter of the production string, m.

[0064] In a possible design, the determining of the throttled production string pressure and the throttled production string temperature corresponding to the production string includes: determining the gas compression factor of the production string according to the pressure in the first sub-production string when blockage is not considered, the temperature in the first sub-production string when blockage is not considered, and the relative density of the gas; calculating the gas production rate under critical throttling conditions according to the gas compression factor of the production string, the pressure in the first sub-production string when blockage is not considered, the throttling hole area of ​​the production string, the adiabatic index of the leaked gas, the gas molar mass, the gas constant, and the temperature in the first sub-production string when blockage is not considered; judging whether the production string is in a critical throttling state according to the gas production rate and the gas production rate; if the production string is in a critical throttling state, then determining the gas production rate according to the pressure in the first sub-production string when blockage is not considered and the leaked gas; The pressure of the production string after throttling is calculated according to the adiabatic index of the leaking gas, the gas production rate, the standard density of the gas, the pressure in the first sub-production string when blockage is not considered, the throttling hole area of ​​the production string, the gas compression factor, the gas constant, the temperature in the first sub-production string when blockage is not considered, and the gas molar mass. The pressure of the production string after throttling is calculated according to the pressure ratio before and after throttling and the pressure in the first sub-production string when blockage is not considered; the temperature of the production string after throttling is calculated according to the pressure of the production string after throttling, the compression factor before throttling, the compression factor after throttling, the pressure in the first sub-production string when blockage is not considered, the adiabatic index of the leaking gas, and the temperature in the first sub-production string when blockage is not considered.

[0065] In a possible design, the calculation formula for determining the gas compressibility factor of the production string based on the pressure in the first sub-production string without considering blockage, the temperature in the first sub-production string without considering blockage, and the relative density of the gas includes:

[0066]

[0067] In the formula, Z g is the gas compression factor, dimensionless; A1, A2, A3, A4, A5, A6, A7, A8, A9, A 10 is a constant, dimensionless, and is 1.1153, -0.079, 0.01588, 0.00886, -2.1619, 1.1575, -0.05368, 0.014655, -1.80997, 0.9548 respectively; p fL is the pressure in the first sub-production string without considering blockage, MPa; γ g is the relative density of the gas, dimensionless; pr is the quasi-comparison pressure, an intermediate quantity, dimensionless; T r is the temperature to be compared, an intermediate quantity, dimensionless; T fL is the temperature in the first sub-production string without considering blockage, °C;

[0068] Accordingly, the calculation formula for calculating the gas production rate under critical throttling conditions according to the gas compression factor of the production string, the pressure in the first sub-production string when blockage is not considered, the throttling hole area of ​​the production string, the adiabatic index of the leaking gas, the gas molar mass, the gas constant, and the temperature in the first sub-production string when blockage is not considered includes:

[0069]

[0070] In the formula, Q Lg is the gas production rate under critical throttling conditions, m 3 / d;p fL A is the pressure in the first sub-production string without considering blockage, MPa; L is the throttling hole area of ​​the production string, m2; ρ s is the standard density of the gas, kg / m 3 ; Zg is the gas compressibility factor, dimensionless; R is the gas constant, taken as 8.3414; M g is the gas molar mass, kg / mol; T fL is the temperature in the first sub-production string without considering blockage, °C; k g is the adiabatic index of the leaking gas, which is 1.66 and dimensionless;

[0071] Accordingly, the calculation formula for judging whether the production string is in a critical throttling state according to the gas production rate and the gas production rate includes:

[0072]

[0073] Where Q is the gas production rate, m 3 / d;Q Lg is the gas production rate under critical throttling conditions, m 3 / d; E1 is the error, dimensionless;

[0074] Accordingly, the calculation formula for calculating the pressure of the production string after throttling based on the pressure in the first sub-production string without considering blockage and the adiabatic index of the leaked gas includes:

[0075]

[0076] Where P J is the production string pressure after throttling; kg is the adiabatic index of the leaking gas, which is 1.66 and dimensionless; p fL is the pressure in the first sub-production string without considering blockage, MPa;

[0077] Accordingly, the calculation formula for calculating the pressure ratio before and after throttling according to the adiabatic index of the leaking gas, the gas production rate, the gas standard density, the pressure in the first sub-production string when blockage is not considered, the throttling hole area of ​​the production string, the gas compression factor, the gas constant, the temperature in the first sub-production string when blockage is not considered, and the gas molar mass includes:

[0078]

[0079] Where, C is the pressure ratio before and after throttling, dimensionless, C is less than 1; Q is the gas production rate, m 3 / d;ρ s is the standard density of the gas; p fL A is the pressure in the first sub-production string without considering blockage, MPa; L is the throttling hole area of ​​the production string, m2; k g is the adiabatic index of the leaking gas, which is 1.66 and dimensionless; Z g is the gas compression factor, dimensionless; R is the gas constant, taken as 8.3414; T fL is the temperature in the first sub-production string without considering blockage, °C; M g is the molar mass of the gas, kg / mol;

[0080] Accordingly, the calculation formula for calculating the pressure of the production string after throttling based on the pressure ratio before and after throttling and the pressure in the first sub-production string without considering blockage includes:

[0081]

[0082] Where P J is the pressure of the production string after throttling; C is the pressure ratio before and after throttling, dimensionless, C is less than 1; p fL is the pressure in the first sub-production string without considering blockage, MPa;

[0083] Accordingly, the method of calculating the temperature of the production string after throttling according to the production string pressure after throttling, the compression factor before throttling, the compression factor after throttling, the pressure in the first sub-production string when blockage is not considered, the adiabatic index of the leaked gas, and the temperature in the first sub-production string when blockage is not considered includes:

[0084]

[0085] Where, T J is the temperature after throttling, ℃; Z fL is the compression factor before throttling, dimensionless; Z J is the compression factor after throttling, dimensionless; P J is the production string pressure after throttling; p fL is the pressure in the first sub-production string without considering blockage, MPa; k g is the adiabatic index of the leaking gas, which is 1.66 and dimensionless; T fL is the temperature inside the first sub-production string without considering blockage, ℃.

[0086] In a possible design, judging whether the production string meets the collapse condition based on the dynamic pressure in the first sub-production string and the calculated wellhead pressure includes: judging whether the calculated wellhead pressure and the measured wellhead pressure meet a first preset error; if the calculated wellhead pressure and the measured wellhead pressure meet the preset error, judging that the calculated wellhead pressure and the measured wellhead pressure are equal; calculating the collapse pressure of the production string based on the initial annulus pressure, the annulus gas density, the gravitational acceleration, the annulus liquid density, the collapse depth and the annulus liquid depth; judging the dynamic Whether the pressure in the first sub-production string and the collapse pressure satisfy the second preset error; if the dynamic pressure in the first sub-production string and the collapse pressure satisfy the second preset error, then it is determined that the dynamic pressure in the first sub-production string and the collapse pressure are equal; if the wellhead calculated pressure and the wellhead measured pressure are equal, and the dynamic pressure in the first sub-production string and the collapse pressure are equal, then it is determined that the production string meets the collapse condition; if the wellhead calculated pressure and the wellhead measured pressure are not equal, and / or the dynamic pressure in the first sub-production string and the collapse pressure are not equal, then it is determined that the production string does not meet the collapse condition.

[0087] In a possible design, the calculation formula for determining whether the wellhead calculated pressure and the wellhead measured pressure satisfy a first preset error includes:

[0088]

[0089] In the formula, Calculate the pressure at the wellhead; p w2 is the wellhead measured pressure; E is the first preset error;

[0090] Accordingly, the calculation of the collapse pressure of the production string according to the initial annulus pressure, the annulus gas density, the gravitational acceleration, the annulus liquid density, the collapse depth and the annulus liquid depth comprises:

[0091]

[0092] Where P tw is the collapse pressure of the production string, MPa; p an is the initial annular pressure, MPa; ρ ga is the annular gas density, kg / m 3 ; g is the acceleration due to gravity; ρ L is the density of the annular liquid, kg / m 3 ;h cc is the crush depth, m; h g is the annulus liquid depth, m;

[0093] Accordingly, the calculation formula for judging whether the dynamic pressure in the first sub-production string and the collapse pressure satisfy the second preset error includes:

[0094]

[0095] In the formula, is the anti-external collapse strength of the oil pipe, MPa; P tw is the collapse pressure of the production string, MPa; is the dynamic pressure in the first sub-production string; 1.0 is the second preset error.

[0096] In a possible design, the method of obtaining the initial operating parameters of the wellbore and judging whether the production tubing in the wellbore is leaking and crushed according to the initial operating parameters includes: obtaining the operating parameters of the wellbore, wherein the wellbore at least includes a wellhead, an oil casing annulus and a production tubing; the operating parameters at least include the annulus pressure of the oil casing annulus, the wellhead oil pressure and the pressure inside the production tubing; judging whether the production tubing is leaking according to the annulus pressure and the wellhead oil pressure; if it is judged that the production tubing is leaking, judging whether the production tubing is blocked according to the pressure inside the production tubing, the annulus pressure and the wellhead oil pressure; if it is judged that the production tubing is blocked, judging whether the production tubing is crushed.

[0097] The wellbore blockage position detection method provided by the present application determines the leakage and crushing depth of the production string by judging the leakage and crushing of the production string; divides the production string into multiple first sub-production strings; calculates the pressure inside each first sub-production string, wherein the inner diameter size of the production string affects the pressure inside each first sub-production string; divides the inner diameter of the production string into multiple sizes to be adjusted according to a preset ratio to generate the corresponding dynamic pressure inside the first sub-production string; determines the numbers of the corresponding first sub-production strings as the first number, the second number and the third number respectively according to the leakage depth, the crushing depth and the bottom hole depth; determines the throttled production string pressure and the throttled production string temperature corresponding to the production string; and calculates the throttled production string pressure The pressure at the blockage point of the production string is determined, and the temperature of the production string after throttling is determined as the temperature at the blockage point of the production string; the blockage position of the corresponding production string is determined according to the pressure of the production string after throttling and the temperature of the production string after throttling, wherein the blockage position is between the first number and the second number; the wellhead calculated pressure is determined according to the pressure at the blockage point of the production string, the temperature at the blockage point of the production string and the third number; whether the production string meets the crushing condition is determined according to the dynamic pressure in the first sub-production string and the wellhead calculated pressure; if it is determined that the production string meets the crushing condition, the blockage position of the production string is output, so that the wellbore blockage position can be detected, so as to determine the blockage situation of the wellbore blockage position, which is used to analyze the crushing cause of the production string. BRIEF DESCRIPTION OF THE DRAWINGS

[0098] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0099] Figure 1 A schematic diagram of the structure of a wellbore provided in an embodiment of the present application;

[0100] Figure 2 Schematic diagram of the process of the wellbore blockage position detection method provided in the embodiment of the present application Figure 1 ;

[0101] Figure 3 Schematic diagram of the process of the wellbore blockage position detection method provided in the embodiment of the present application Figure 2 . DETAILED DESCRIPTION

[0102] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0103] A wellbore refers to a vertical or inclined engineering structure excavated from the ground to the underground during oil and gas extraction or underground engineering construction. Wellbores are widely used in natural gas development and underground storage, compressed air energy storage, and underground hydrogen storage. They are an important support for the efficient use of clean energy. Wellbores are used to transmit gas from underground gas reservoirs to the ground. However, wellbores are prone to blockage during the production process, causing damage to the internal structure of the wellbore, which in turn affects the normal operation of the wellbore. However, there is currently no effective detection method for determining the location of wellbore blockage. Therefore, there is an urgent need for a method that can detect the location of wellbore blockage to determine the blockage situation of the wellbore blockage location.

[0104] In order to solve the above technical problems, the embodiments of the present application propose the following technical concepts: the inventors consider that after determining that the production tubing is leaking and being crushed, the leakage depth and crushing depth of the production tubing are determined, and the blockage position of the production tubing and the dynamic pressure inside the first sub-production tubing are determined based on the operating parameters of the wellbore, the leakage depth and the crushing depth. The dynamic pressure inside the first sub-production tubing and the pre-generated wellhead calculated pressure are used to determine whether the production tubing meets the crushing condition. If it is determined that the production tubing meets the crushing condition, the blockage position of the production tubing is output, so that the wellbore blockage position can be detected to determine the blockage condition of the wellbore blockage position.

[0105] Figure 1 A schematic diagram of the structure of a wellbore provided in an embodiment of the present application.

[0106] like Figure 1 As shown, the structure of the wellbore specifically includes: a wellhead 101 , an oil casing annulus 102 , annulus liquid 103 , casing annulus 104 , a production casing 105 , a production tubing string 106 , a technical casing 107 and a packer 108 .

[0107] The casing annulus 102 is an annular space formed by the wellhead 101 , the production casing 105 , the production tubing string 106 and the packer 108 .

[0108] The annular space liquid 103 is stored in the casing annulus 102 and is used to protect the production casing 105 and the production tubing string 106 .

[0109] The casing annulus 104 is an annular space formed by the wellhead 101 , the production casing 105 and the technical casing 107 .

[0110] The production string 106 is formed by splicing a plurality of oil pipes and is used for transmitting gas.

[0111] The packer 108 is used to fix the production tubing 105 .

[0112] Furthermore, the blockage position is located between the collapse position and the leakage position.

[0113] Figure 2 Schematic diagram of the process of the wellbore blockage position detection method provided in the embodiment of the present application Figure 1 The execution subject of this embodiment can be a computer device, and this embodiment is not particularly limited here. Figure 2 As shown, the method includes:

[0114] S201: Acquire initial operating parameters of the wellbore, and determine whether the production tubing in the wellbore is leaking or crushed according to the initial operating parameters.

[0115] Specifically, step S201 includes:

[0116] S2011: Acquire the operating parameters of the wellbore, the wellbore at least includes the wellhead, the casing annulus and the production string, and the operating parameters at least include the annulus pressure of the casing annulus, the wellhead oil pressure and the pressure inside the production string.

[0117] S2012: Determine whether the production tubing is leaking based on the annulus pressure and wellhead oil pressure.

[0118] Specifically, step S2012 includes:

[0119] First, adjust the wellbore production to change the pressure profile in the production string. The adjustment range should not be less than 10% of the initial gas production rate. Observe the changing trends of the annulus pressure and the wellhead oil pressure. When the annulus pressure change trend is consistent with the wellhead oil pressure, it can be preliminarily determined that the annulus pressure is caused by leakage of the production string. The judgment of consistent changing trends is: when the oil pressure rises, the annulus pressure rises synchronously, and when the oil pressure drops, the annulus pressure drops synchronously.

[0120] Then, the annular pressure is released at the wellhead, and the leaked fluid is collected and tested for composition. When the fluid composition is consistent with the fluid composition produced at the wellhead, it can be determined that the production string is leaking.

[0121] S2013: If the production string is determined to be leaking, determine whether the production string is blocked based on the pressure inside the production string, the annular pressure, and the wellhead oil pressure.

[0122] Specifically, step S2013 includes:

[0123] When the production string is blocked, the pressure in the production string above the blocking position changes, which is manifested as a drop in wellhead oil pressure. Therefore, by observing the wellhead oil pressure change curve and the annulus pressure change curve, when the wellhead oil pressure drops while the annulus pressure remains unchanged, it can be determined that the production string is blocked.

[0124] S2014: If it is determined that the production tubing is blocked, it is determined that the production tubing is crushed.

[0125] In this embodiment, the blockage position occurs between the collapse depth and the leakage depth, so it is determined that the production string has collapsed.

[0126] S202: If the production string is determined to be leaking or crushed, the shutdown parameters of the wellbore are obtained, and the leakage depth of the production string is determined according to the shutdown parameters.

[0127] S203: Determine the collapse depth of the production string according to a preset logging method.

[0128] In this embodiment, the preset logging method may be a multi-arm caliper method, a lead printing method, an electromagnetic flaw detection method, or other methods.

[0129] S204: Divide the portion from the bottom of the production string to the collapse depth into a plurality of first sub-production strings according to a first preset length.

[0130] In this embodiment, the production string is composed of a plurality of oil pipes; the first preset length is less than or equal to one fifth of the oil pipes.

[0131] S205: Acquire the operating parameters of the wellbore, and calculate the pressure in each first sub-production string according to the operating parameters, wherein the inner diameter of the production string affects the pressure in each first sub-production string.

[0132] Specifically, step S205 includes:

[0133] S2051: Obtain the operating parameters of the wellbore, which include at least dimensionless time, well opening and production time, formation heat diffusion coefficient, wellbore radius, ratio of wellbore specific heat capacity to formation specific heat capacity, gas standard density, gas production rate, gas temperature in the production string, formation thermal conductivity, initial formation temperature, gas specific heat capacity in the production string, radial heat transfer resistance, standard temperature, standard pressure, production string roughness, gas viscosity in the production string and inner diameter of the production string.

[0134] S2052: Calculate the dimensionless formation temperature based on the dimensionless time, well opening and production time, formation heat diffusion coefficient, wellbore radius, and the ratio of the specific heat capacity of the wellbore to the specific heat capacity of the formation.

[0135] In this embodiment, the dimensionless formation temperature is calculated according to the dimensionless time, the well opening production time, the formation heat diffusion coefficient, the wellbore radius, and the ratio of the wellbore specific heat capacity to the formation specific heat capacity. The calculation formula includes:

[0136]

[0137] Where, T D is the dimensionless formation temperature, dimensionless; t D is dimensionless time, dimensionless; t is the well opening production time, s; α e is the formation heat diffusion coefficient, m 2 / s;r w is the wellbore radius, m; ω is the ratio of the specific heat capacity of the wellbore to the specific heat capacity of the formation, dimensionless.

[0138] S2053: Calculate the gas mass flow rate in the production string based on the standard gas density and the gas production rate.

[0139] In this embodiment, the calculation formula for calculating the gas mass flow rate in the production string according to the gas standard density and the gas production rate includes:

[0140]

[0141] In the formula, w f is the gas mass flow rate in the production column, kg / s; Q is the gas production rate, m 3 / d;ρ s is the standard density of the gas, kg / m 3 .

[0142] S2054: Calculate the corresponding gas temperature in the first sub-production string based on the dimensionless formation temperature, gas mass flow rate, gas temperature in the previous first sub-production string, the first preset length, formation thermal conductivity, initial formation temperature corresponding to the first sub-production string, gas specific heat capacity in the production string, and radial heat transfer thermal resistance.

[0143] In this embodiment, the calculation formula for calculating the corresponding gas temperature in the first sub-production string is calculated based on the dimensionless formation temperature, the gas mass flow rate, the gas temperature in the previous first sub-production string, the first preset length, the formation thermal conductivity, the initial formation temperature corresponding to the first sub-production string, the gas specific heat capacity in the production string, and the radial heat transfer thermal resistance, including:

[0144]

[0145] Where, T f i is the gas temperature in the first sub-production column of the i-th section, °C; T D is the dimensionless formation temperature; Tf i-1 is the gas temperature in the first sub-production string of the i-th section corresponding to the previous section, °C; h fd1 is the first preset length, m; λ e is the formation thermal conductivity, W / (m·℃); T e i The initial formation temperature corresponding to the first sub-production string of the i-th section, °C; w f is the gas mass flow rate in the production string, kg / s; C f is the specific heat capacity of the gas in the production column, J / (kg·℃); R to i is the radial heat transfer resistance of the i-th wellbore segment with length △z, m·℃ / W.

[0146] Where, let i = 0, then the initial gas temperature in the first sub-production string is: T f i =T0+g e h w ,h w is the depth of the well bottom.

[0147] S2055: Calculate the gas density in each first sub-production string according to the gas temperature in each first sub-production string, the pressure in each first sub-production string, the standard temperature, the standard pressure, and the standard density of the gas.

[0148] In this embodiment, the calculation formula for calculating the gas density in each first sub-production string according to the gas temperature in each first sub-production string, the pressure in each first sub-production string, the standard temperature, the standard pressure and the standard density of the gas includes:

[0149]

[0150] In the formula, is the gas density in the first sub-production string of section i-1, kg / m 3 ; T f i-1 is the gas temperature in the first sub-production string corresponding to the i-1th section; P i-1 is the pressure in the first sub-production string of the i-1th section, MPa; T s is the standard temperature, °C; p s is the standard pressure, MPa; ρ s is the standard density of the gas, kg / m 3 .

[0151] S2056: Calculate the gas flow rate in each first sub-production string according to the gas density, gas production rate and standard gas density in each first sub-production string.

[0152] In this embodiment, the calculation formula for calculating the gas flow rate in each first sub-production string according to the gas density, gas production rate and gas standard density in each first sub-production string includes:

[0153]

[0154] In the formula, is the gas flow rate in the first sub-production string of the i-1th section, m / s; Q is the gas production rate, m 3 / d;ρ s is the standard density of the gas, kg / m 3 ;d tn is the inner diameter of the production string, m; is the gas density in the first sub-production string of section i-1, kg / m 3 .

[0155] S2057: Calculate the friction coefficient of each first sub-production string according to the roughness of the production string, the viscosity of the gas in the production string, the inner diameter of the production string, the gas density in each first sub-production string, and the gas flow rate in each first sub-production string.

[0156] In this embodiment, the friction coefficient of each first sub-production string is calculated according to the roughness of the production string, the viscosity of the gas in the production string, the inner diameter of the production string, the gas density in each first sub-production string, and the gas flow rate in each first sub-production string. The calculation formula includes:

[0157]

[0158] In the formula, f i-1 is the friction coefficient of the first sub-production string of the i-1th section, dimensionless; Ra is the roughness of the production string, m; μ is the gas viscosity in the production string, Pa·s; is the gas density in the first sub-production string of section i-1, kg / m 3 ; is the gas flow rate in the first sub-production string of the i-1th section, m / s; d tn i is the inner diameter of the first sub-production string of the i-th section, m.

[0159] S2058: Calculate the pressure in each first sub-production string according to the friction coefficient of each first sub-production string, the gas density in each first sub-production string, the first preset length, the inner diameter of the production string, and the gas flow rate in each first sub-production string.

[0160] In this embodiment, the calculation formula for calculating the pressure in each first sub-production string according to the friction coefficient of each first sub-production string, the gas density in each first sub-production string, the first preset length, the inner diameter of the production string, and the gas flow rate in each first sub-production string includes:

[0161]

[0162] In the formula, is the pressure in the first sub-production string corresponding to the i-th section; is the pressure in the first sub-production string corresponding to the i-1th section; h fd1 is the first preset length, m; Gas density in the first sub-production string of section i-1, kg / m 3 ;f i-1 is the friction coefficient of the first sub-production string of the i-1th section, dimensionless; is the gas flow rate in the first sub-production string of the i-1th section, m / s; d tn is the inner diameter of the production string, m.

[0163] Where, let i = 0, then the initial pressure in the first sub-production string is: P f 0 =P w , P w is the bottom hole pressure.

[0164] S206: Divide the inner diameter of the production tubing into a plurality of sizes to be adjusted according to a preset ratio.

[0165] In this embodiment, the inner diameter of the production string is divided into a plurality of sizes to be adjusted according to a preset ratio, and the calculation formula includes:

[0166]

[0167] Where, d max The maximum inner diameter of the production string; d tn is the inner diameter of the production string; △d is the preset ratio; d min The minimum inner diameter of the production string.

[0168] In this embodiment, the preset ratio is less than or equal to 1 / 100 of the inner diameter of the production string.

[0169] S207: adjusting the inner diameter of the production string from large to small according to a plurality of sizes to be adjusted, so as to generate a corresponding dynamic inner pressure of the first sub-production string.

[0170] S208: Determine the numbers corresponding to the first sub-production tubing string as the first number, the second number, and the third number respectively according to the leakage depth, the collapse depth, and the bottom hole depth.

[0171] In this embodiment, the calculation formula for determining the numbers of the first sub-production string as the first number, the second number, and the third number respectively according to the leakage depth, the collapse depth, and the bottom hole depth includes:

[0172]

[0173] Where M is the first number, a dimensionless integer; h LL is the leakage depth, m; N is the second number, a dimensionless integer; h cc is the collapse depth, m; X is the third number, a dimensionless integer; h w is the bottom depth of the well; H fd1 is the first preset length.

[0174] S209: Determine the throttled production string pressure and throttled production string temperature corresponding to the production string.

[0175] Specifically, step S209 includes:

[0176] S2091: Determine the gas compression factor of the production string according to the pressure in the first sub-production string when blockage is not considered, the temperature in the first sub-production string when blockage is not considered, and the relative density of the gas.

[0177] In this embodiment, the calculation formula for determining the gas compressibility factor of the production string according to the pressure in the first sub-production string without considering blockage, the temperature in the first sub-production string without considering blockage, and the relative density of the gas includes:

[0178]

[0179] In the formula, Z g is the gas compression factor, dimensionless; A1, A2, A3, A4, A5, A6, A7, A8, A9, A 10 is a constant, dimensionless, and is 1.1153, -0.079, 0.01588, 0.00886, -2.1619, 1.1575, -0.05368, 0.014655, -1.80997, 0.9548 respectively; p fL is the pressure in the first sub-production string without considering blockage, MPa; γ g is the relative density of the gas, dimensionless; p r is the quasi-comparison pressure, an intermediate quantity, dimensionless; T r is the temperature to be compared, an intermediate quantity, dimensionless; T fL is the temperature inside the first sub-production string without considering blockage, ℃.

[0180] S2092: Calculate the gas production rate under critical throttling conditions based on the gas compression factor of the production string, the pressure in the first sub-production string without considering blockage, the throttling hole area of ​​the production string, the adiabatic index of the leaking gas, the gas molar mass, the gas constant, and the temperature in the first sub-production string without considering blockage.

[0181] In this embodiment, the calculation formula for calculating the gas production rate under critical throttling is based on the gas compression factor of the production string, the pressure in the first sub-production string without considering blockage, the throttling hole area of ​​the production string, the adiabatic index of the leaked gas, the gas molar mass, the gas constant, and the temperature in the first sub-production string without considering blockage, including:

[0182]

[0183] In the formula, Q Lg is the gas production rate under critical throttling conditions, m 3 / d;p fL A is the pressure in the first sub-production string without considering blockage, MPa; L is the throttling hole area of ​​the production string, m2; ρ s is the standard density of the gas, kg / m 3 ; Zg is the gas compressibility factor, dimensionless; R is the gas constant, taken as 8.3414; M g is the gas molar mass, kg / mol; T fL is the temperature in the first sub-production string without considering blockage, °C; k g is the adiabatic index of the leaking gas, which is taken as 1.66 and is dimensionless.

[0184] S2093: Determine whether the production string is in a critical throttling state based on the gas production rate and the gas production rate.

[0185] In this embodiment, the calculation formula for judging whether the production string is in a critical throttling state according to the gas production rate and the gas production rate includes:

[0186]

[0187] Where Q is the gas production rate, m 3 / d;Q Lg is the gas production rate under critical throttling conditions, m 3 / d; E1 is the error and has no dimension.

[0188] S2094: If the production string is in a critical throttling state, the pressure of the production string after throttling is calculated based on the pressure in the first sub-production string without considering blockage and the adiabatic index of the leaked gas.

[0189] In this embodiment, the calculation formula for calculating the pressure of the production string after throttling based on the pressure in the first sub-production string and the adiabatic index of the leaked gas without considering the blockage includes:

[0190]

[0191] Where P J is the production string pressure after throttling; k g is the adiabatic index of the leaking gas, which is 1.66 and dimensionless; p fL is the pressure in the first sub-production string without considering blockage, MPa.

[0192] S2095: If the production string is not in a critical throttling state, the pressure ratio before and after throttling is calculated based on the adiabatic index of the leaking gas, the gas production rate, the standard gas density, the pressure in the first sub-production string without considering blockage, the throttling hole area of ​​the production string, the gas compression factor, the gas constant, the temperature in the first sub-production string without considering blockage, and the gas molar mass.

[0193] In this embodiment, the calculation formula for calculating the pressure ratio before and after throttling is based on the adiabatic index of the leaking gas, the gas production rate, the gas standard density, the pressure in the first sub-production string without considering blockage, the throttling hole area of ​​the production string, the gas compression factor, the gas constant, the temperature in the first sub-production string without considering blockage, and the gas molar mass, including:

[0194]

[0195] Where, C is the pressure ratio before and after throttling, dimensionless, C is less than 1; Q is the gas production rate, m 3 / d;ρ s is the standard density of the gas; p fL A is the pressure in the first sub-production string without considering blockage, MPa; L is the throttling hole area of ​​the production string, m2; k g is the adiabatic index of the leaking gas, which is 1.66 and dimensionless; Z g is the gas compression factor, dimensionless; R is the gas constant, taken as 8.3414; T fL is the temperature in the first sub-production string without considering blockage, °C; M g is the molar mass of the gas, kg / mol.

[0196] S2096: Calculate the pressure of the production string after throttling based on the pressure ratio before and after throttling and the pressure in the first sub-production string without considering blockage.

[0197] In this embodiment, the calculation formula for calculating the pressure of the production string after throttling based on the pressure ratio before and after throttling and the pressure in the first sub-production string without considering blockage includes:

[0198]

[0199] Where P J is the pressure of the production string after throttling; C is the pressure ratio before and after throttling, dimensionless, C is less than 1; p fL is the pressure in the first sub-production string without considering blockage, MPa.

[0200] S2097: Calculate the temperature of the production string after throttling based on the production string pressure after throttling, the compression factor before throttling, the compression factor after throttling, the pressure in the first sub-production string without considering blockage, the adiabatic index of the leaked gas, and the temperature in the first sub-production string without considering blockage.

[0201] In this embodiment, the temperature of the production string after throttling is calculated according to the pressure of the production string after throttling, the compression factor before throttling, the compression factor after throttling, the pressure in the first sub-production string without considering blockage, the adiabatic index of the leaked gas, and the temperature in the first sub-production string without considering blockage, including:

[0202]

[0203] Where, T J is the temperature after throttling, ℃; Z fL is the compression factor before throttling, dimensionless; Z J is the compression factor after throttling, dimensionless; P J is the production string pressure after throttling; p fL is the pressure in the first sub-production string without considering blockage, MPa; k g is the adiabatic index of the leaking gas, which is 1.66 and dimensionless; T fL is the temperature inside the first sub-production string without considering blockage, ℃.

[0204] S210: The pressure of the production tubing string after throttling is determined as the pressure at the blockage point of the production tubing string, and the temperature of the production tubing string after throttling is determined as the temperature at the blockage point of the production tubing string.

[0205] S211: Determine a blockage position of a corresponding production string according to the pressure of the production string after throttling and the temperature of the production string after throttling, wherein the blockage position is between the first number and the second number.

[0206] In this embodiment, the calculation formula for determining the blockage position of the corresponding production string according to the production string pressure after throttling and the production string temperature after throttling includes:

[0207]

[0208] In the formula, is the temperature corresponding to the plugging position of the production string; Y is the number of the first sub-production string corresponding to the plugging position; is the temperature of the production string after throttling; The pressure corresponding to the blockage position of the production string; is the production string pressure after throttling.

[0209] Among them, N≥Y≥M.

[0210] S212: Determine the wellhead calculated pressure according to the pressure at the production tubing blockage point, the temperature at the production tubing blockage point, and the third number.

[0211] S213: judging whether the production string meets the collapse condition according to the dynamic pressure in the first sub-production string and the calculated pressure at the wellhead.

[0212] Specifically, step S213 includes:

[0213] S2131: Determine whether the wellhead calculated pressure and the wellhead measured pressure satisfy a first preset error.

[0214] In this embodiment, the calculation formula for judging whether the wellhead calculated pressure and the wellhead measured pressure satisfy the first preset error includes:

[0215]

[0216] In the formula, Calculate the pressure at the wellhead; p w2 is the measured pressure at the wellhead; E is the first preset error.

[0217] S2132: If the wellhead calculated pressure and the wellhead measured pressure satisfy a preset error, it is determined that the wellhead calculated pressure and the wellhead measured pressure are equal.

[0218] In addition, if the wellhead calculated pressure and the wellhead measured pressure do not satisfy the preset error, the preset ratio of the production string inner diameter division is reset and the subsequent steps are re-executed.

[0219] S2133: Calculate the collapse pressure of the production string based on the initial annulus pressure, annulus gas density, gravity acceleration, annulus liquid density, collapse depth and annulus liquid depth.

[0220] In this embodiment, the collapse pressure of the production string is calculated according to the initial annular space pressure, the annular space gas density, the gravity acceleration, the annular space liquid density, the collapse depth and the annular space liquid depth, including:

[0221]

[0222] Where P tw is the collapse pressure of the production string, MPa; p an is the initial annular pressure, MPa; ρ ga is the annular gas density, kg / m 3 ; g is the acceleration due to gravity; ρ L is the density of the annular liquid, kg / m 3 ;h cc is the crush depth, m; h g is the annulus liquid depth, m.

[0223] S2134: Determine whether the dynamic pressure in the first sub-production string and the collapse pressure satisfy a second preset error.

[0224] In this embodiment, the calculation formula for judging whether the dynamic pressure in the first sub-production string and the collapse pressure satisfy the second preset error includes:

[0225]

[0226] In the formula, is the anti-external collapse strength of the oil pipe, MPa; P tw is the collapse pressure of the production string, MPa; is the dynamic pressure in the first sub-production string; 1.0 is the second preset error.

[0227] S2135: If the dynamic pressure in the first sub-production string and the collapse pressure satisfy a second preset error, it is determined that the dynamic pressure in the first sub-production string and the collapse pressure are equal.

[0228] S2136: If the calculated wellhead pressure is equal to the measured wellhead pressure, and the dynamic pressure in the first sub-production string is equal to the crushing pressure, then it is determined that the production string meets the crushing condition; if the calculated wellhead pressure is not equal to the measured wellhead pressure, and / or the dynamic pressure in the first sub-production string is not equal to the crushing pressure, then it is determined that the production string does not meet the crushing condition.

[0229] S214: If it is determined that the production string meets the collapse condition, the blockage position of the production string is output.

[0230] In addition, if it is determined that the production string does not meet the collapse condition, the compression factor is recalculated and the subsequent steps are re-executed.

[0231] In summary, the method for detecting the wellbore blockage position provided in the present embodiment determines the leakage and collapse of the production tubing by determining the leakage and collapse of the production tubing; divides the production tubing into a plurality of first sub-production tubings; calculates the pressure inside each first sub-production tubing, wherein the inner diameter of the production tubing affects the pressure inside each first sub-production tubing; divides the inner diameter of the production tubing into a plurality of sizes to be adjusted according to a preset ratio to generate the corresponding dynamic pressure inside the first sub-production tubing; determines the numbers of the corresponding first sub-production tubings as the first number, the second number, and the third number respectively according to the leakage depth, the collapse depth, and the bottom hole depth; determines the throttled production tubing pressure and the throttled production tubing temperature corresponding to the production tubing; and calculates the throttled production tubing pressure. The pressure of the production string is determined as the pressure at the blockage point of the production string, and the temperature of the production string after throttling is determined as the temperature at the blockage point of the production string; the blockage position of the corresponding production string is determined according to the pressure of the production string after throttling and the temperature of the production string after throttling, wherein the blockage position is between the first number and the second number; the wellhead calculated pressure is determined according to the pressure at the blockage point of the production string, the temperature at the blockage point of the production string and the third number; whether the production string meets the crushing condition is judged according to the dynamic pressure in the first sub-production string and the wellhead calculated pressure; if it is determined that the production string meets the crushing condition, the blockage position of the production string is output, so that the wellbore blockage position can be detected, so as to determine the blockage situation of the wellbore blockage position, which is used to analyze the crushing cause of the production string.

[0232] Figure 3 Schematic diagram of the process of the wellbore blockage position detection method provided in the embodiment of the present application Figure 2 In the embodiment of the present application, Figure 2 Based on the embodiment provided, a specific implementation method for obtaining the wellbore shutdown parameters in step S202 and determining the leakage depth of the production string according to the shutdown parameters is described in detail. Figure 3 As shown, the method includes:

[0233] S301: Acquire the shutdown parameters of the wellbore, which include at least the initial annular pressure of the casing annulus, the annular gas density, the gas depth of the casing annulus, the annular liquid density, the annular liquid depth, the surface temperature, the geothermal gradient, the standard pressure, the standard temperature and the standard gas density.

[0234] Among them, the annulus liquid depth can be measured by ultrasonic echo method.

[0235] S302: Determine the annular pressure of the casing annulus at different depths according to the initial annular pressure, annular gas density, gas depth, annular liquid density and annular liquid depth.

[0236] In this embodiment, the calculation formula for determining the annular pressure of the casing annulus at different depths is as follows according to the initial annular pressure, annular gas density, gas depth, annular liquid density, and annular liquid depth, including:

[0237]

[0238] In the formula, p aL The depth is h L Annulus pressure of casing annulus, MPa; p an is the initial annular pressure, MPa; ρ ga is the annular gas density, kg / m 3 ; g is the acceleration due to gravity; ρ L is the density of the annular liquid, kg / m 3 ;h L is the gas depth, m; h g is the annulus liquid depth, m.

[0239] S303: Divide the production string into a plurality of second sub-production strings according to a second preset length.

[0240] In this embodiment, the production string is composed of a plurality of oil pipes; the second preset length is less than or equal to one fifth of the length of the oil pipes.

[0241] S304: Calculating the temperature of each second sub-production string according to the surface temperature, the geothermal gradient and the second preset length.

[0242] In this embodiment, the temperature of each second sub-production string is calculated according to the surface temperature, the geothermal gradient and the second preset length, including:

[0243]

[0244] Where, T k is the temperature of the second sub-production string of the kth section, ℃; T0 is the surface temperature, ℃; g e is the geothermal gradient, ℃ / m; h fd2 is the second preset length.

[0245] When k=1, T 1 =T0.

[0246] S305: Calculate the gas density in the initial second sub-production string according to the temperature of each second sub-production string, the initial pressure in the second sub-production string, the standard pressure, the standard temperature and the standard density of the gas.

[0247] In this embodiment, the calculation formula for calculating the gas density in the initial second sub-production string according to the temperature of each second sub-production string, the initial pressure in the second sub-production string, the standard pressure, the standard temperature and the standard density of the gas includes:

[0248]

[0249] In the formula, is the gas density in the second sub-production string of section k, kg / m 3 First, the gas density in the initial second sub-production string needs to be determined; k is the pressure in the second sub-production string of the kth section, MPa, and the start is the initial pressure in the second sub-production string; T s is the standard temperature, °C; p s is the standard pressure, MPa; T k is the temperature of the second sub-production column of the kth section, °C; ρ s is the standard density of the gas, kg / m 3 .

[0250] S306: Calculate the pressure in each second sub-production string according to the gas density of the initial second sub-production string and the second preset length.

[0251] In this embodiment, the calculation formula for calculating the pressure in each second sub-production string according to the gas density of the initial second sub-production string and the second preset length includes:

[0252]

[0253] In the formula, p k+1 is the pressure in the second sub-production string of the k+1th section, MPa; p k is the pressure in the second sub-production string of section k, MPa; is the gas density in the second sub-production string of the kth section, kg / m3; g is the gravitational acceleration; h fd2 is the second preset length.

[0254] When k=1, P 1 =P t .

[0255] S307: Determine the leakage depth of the production string according to the pressure in each second sub-production string and the annular pressure of the casing annulus at different depths.

[0256] Specifically, let k be increased successively until the bottom of the well is calculated, and the pressure inside each second sub-production string can be obtained. In the same figure, the annular pressure of the casing annulus and the pressure inside each second sub-production string are plotted. According to the U-tube principle, the position where the two pressures intersect and are equal is the leakage depth of the production string.

[0257] In summary, the method for detecting the wellbore blockage position provided in the present embodiment determines the annular pressure of the casing annulus at different depths; divides the production string into multiple second sub-production strings according to the second preset length; calculates the temperature of each second sub-production string according to the surface temperature, the geothermal gradient and the second preset length; calculates the gas density in the initial second sub-production string according to the temperature of each second sub-production string, the initial pressure in the second sub-production string, the standard pressure, the standard temperature and the standard density of the gas; calculates the pressure in each second sub-production string according to the gas density of the initial second sub-production string and the second preset length; determines the leakage depth of the production string according to the pressure in each second sub-production string and the annular pressure of the casing annulus at different depths, so that the determination of the leakage depth of the production string is more accurate, laying a foundation for the subsequent detection of the wellbore blockage position.

[0258] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for detecting a wellbore blockage position, characterized in that: Applicable to computer equipment, including: Acquiring initial operating parameters of the wellbore, and judging whether the production tubing in the wellbore is leaking or crushed according to the initial operating parameters; If it is determined that the production tubing string is leaking or crushed, then the shutdown parameter of the wellbore is obtained, and the leakage depth of the production tubing string is determined according to the shutdown parameter; Determine the collapse depth of the production string according to a preset logging method; Dividing the portion from the bottom of the production string to the collapse depth into a plurality of first sub-production strings according to a first preset length; Acquiring operating parameters of the wellbore, and calculating the pressure in each first sub-production string according to the operating parameters, wherein the inner diameter of the production string affects the pressure in each first sub-production string; Dividing the inner diameter of the production tubing into a plurality of sizes to be adjusted according to a preset ratio; The inner diameter of the production string is adjusted from large to small according to a plurality of sizes to be adjusted, so as to generate a corresponding dynamic pressure in the first sub-production string; According to the leakage depth, the collapse depth and the bottom hole depth, the numbers corresponding to the first sub-production tubing string are determined to be the first number, the second number and the third number respectively; Determining a throttled production string pressure and a throttled production string temperature corresponding to the production string; Determine the pressure of the production tubing string after throttling as the pressure at the blockage point of the production tubing string, and determine the temperature of the production tubing string after throttling as the temperature at the blockage point of the production tubing string; Determine a plugging position of a corresponding production string according to the production string pressure after throttling and the production string temperature after throttling, wherein the plugging position is between the first number and the second number; Determine the wellhead calculated pressure according to the pressure at the blockage point of the production tubing string, the temperature at the blockage point of the production tubing string and the third number; Determining whether the production string meets the collapse condition according to the dynamic pressure in the first sub-production string and the wellhead calculated pressure; If it is determined that the production tubing string meets the collapse condition, the blockage position of the production tubing string is output.

2. The method according to claim 1, characterized in that The calculation formula for dividing the inner diameter of the production string into a plurality of sizes to be adjusted according to a preset ratio includes: Where, d max The maximum inner diameter of the production string; d tn is the inner diameter of the production string; △d is the preset ratio; d min The minimum size of the inner diameter of the production string; Accordingly, the calculation formula for determining the numbers of the first sub-production tubing strings as the first number, the second number, and the third number respectively according to the leakage depth, the collapse depth, and the bottom hole depth includes: Where M is the first number, a dimensionless integer; h LL is the leakage depth, m; N is the second number, a dimensionless integer; h cc is the collapse depth, m; X is the third number, a dimensionless integer; h w is the bottom depth of the well; H fd1 is a first preset length; Correspondingly, the calculation formula for determining the blockage position of the corresponding production string according to the production string pressure after throttling and the production string temperature after throttling includes: In the formula, is the temperature corresponding to the plugging position of the production string; Y is the number of the first sub-production string corresponding to the plugging position; is the temperature of the production string after throttling; The pressure corresponding to the blockage position of the production string; is the production string pressure after throttling.

3. The method according to claim 1, characterized in that: The step of obtaining the shutdown parameter of the wellbore and determining the leakage depth of the production string according to the shutdown parameter includes: Acquire the shutdown parameters of the wellbore, wherein the shutdown parameters at least include the initial annular pressure of the casing annulus, the annular gas density, the gas depth of the casing annulus, the annular liquid density, the annular liquid depth, the surface temperature, the geothermal gradient, the standard pressure, the standard temperature and the standard gas density; Determine the annular pressure of the casing annulus at different depths according to the initial annular pressure, the annular gas density, the gas depth, the annular liquid density and the annular liquid depth; Dividing the production tubing string into a plurality of second sub-production tubing strings according to a second preset length; Calculating the temperature of each second sub-production string according to the surface temperature, the geothermal gradient and the second preset length; Calculate the gas density in the initial second sub-production string according to the temperature of each second sub-production string, the initial pressure in the second sub-production string, the standard pressure, the standard temperature and the standard density of the gas; Calculating the pressure in each second sub-production string according to the gas density of the initial second sub-production string and the second preset length; The leakage depth of the production string is determined according to the pressure in each second sub-production string and the annular pressure of the oil casing annulus at different depths.

4. The method according to claim 3, characterized in that The calculation formula for determining the annular pressure of the casing annulus at different depths according to the initial annular pressure, the annular gas density, the gas depth, the annular liquid density and the annular liquid depth includes: In the formula, p aL The depth is h L Annulus pressure of casing annulus, MPa; p an is the initial annular pressure, MPa; ρ ga is the annular gas density, kg / m 3 ; g is the acceleration due to gravity; ρ L is the density of the annular liquid, kg / m 3 ;h L is the gas depth, m; h g is the annulus liquid depth, m; Accordingly, the step of calculating the temperature of each second sub-production string according to the surface temperature, the geothermal gradient and the second preset length includes: Where, T k is the temperature of the second sub-production string of the kth section, ℃; T0 is the surface temperature, ℃; g e is the geothermal gradient, ℃ / m; h fd2 is a second preset length; Accordingly, the calculation formula for calculating the gas density in the initial second sub-production string according to the temperature of each second sub-production string, the initial pressure in the second sub-production string, the standard pressure, the standard temperature and the standard density of the gas includes: In the formula, is the gas density in the second sub-production string of section k, kg / m 3 First, it is necessary to determine the gas density in the initial second sub-production string; k is the pressure in the second sub-production string of the kth section, MPa, starting from the initial pressure in the second sub-production string; T s is the standard temperature, °C; p s is the standard pressure, MPa; T k is the temperature of the second sub-production column of the kth section, °C; ρ s is the standard density of the gas, kg / m 3 ; Accordingly, the calculation formula for calculating the pressure in each second sub-production string according to the gas density of the initial second sub-production string and the second preset length includes: In the formula, p k+1 is the pressure in the second sub-production string of the k+1th section, MPa; p k is the pressure in the second sub-production string of section k, MPa; is the gas density in the second sub-production string of section k, kg / m 3 ; g is the acceleration due to gravity; h fd2 is the second preset length.

5. The method according to claim 1, characterized in that The obtaining of the operating parameters of the wellbore and calculating the pressure in each first sub-production string according to the operating parameters includes: Obtaining the operating parameters of the wellbore, wherein the operating parameters at least include dimensionless time, well opening production time, formation heat diffusion coefficient, wellbore radius, ratio of wellbore specific heat capacity to formation specific heat capacity, gas standard density, gas production rate, gas temperature in the production string, formation thermal conductivity, initial formation temperature, gas specific heat capacity in the production string, radial heat transfer resistance, standard temperature, standard pressure, production string roughness, gas viscosity in the production string, and inner diameter of the production string; Calculating the dimensionless formation temperature according to the dimensionless time, the well opening and production time, the formation heat diffusion coefficient, the wellbore radius, and the ratio of the wellbore specific heat capacity to the formation specific heat capacity; Calculating the gas mass flow rate in the production string according to the gas standard density and the gas production rate; Calculate the corresponding gas temperature in the first sub-production string according to the dimensionless formation temperature, the gas mass flow rate, the gas temperature in the first sub-production string in the previous section, the first preset length, the formation thermal conductivity, the initial formation temperature corresponding to the first sub-production string, the gas specific heat capacity in the production string, and the radial heat transfer thermal resistance; Calculate the gas density in each first sub-production string according to the gas temperature in each first sub-production string, the pressure in each first sub-production string, the standard temperature, the standard pressure and the standard density of the gas; Calculating the gas flow rate in each first sub-production string according to the gas density in each first sub-production string, the gas production rate and the gas standard density; Calculating the friction coefficient of each first sub-production string according to the roughness of the production string, the viscosity of the gas in the production string, the inner diameter of the production string, the gas density in each first sub-production string, and the gas flow rate in each first sub-production string; The pressure in each first sub-production string is calculated according to the friction coefficient of each first sub-production string, the gas density in each first sub-production string, the first preset length, the inner diameter of the production string and the gas flow rate in each first sub-production string.

6. The method according to claim 5, characterized in that The calculation formula for calculating the dimensionless formation temperature according to the dimensionless time, the well opening production time, the formation heat diffusion coefficient, the wellbore radius, and the ratio of the wellbore specific heat capacity to the formation specific heat capacity includes: Where, T D is the dimensionless formation temperature, dimensionless; t D is dimensionless time, dimensionless; t is the well opening production time, s; α e is the formation heat diffusion coefficient, m 2 / s;r w is the borehole radius, m; ω is the ratio of the specific heat capacity of the wellbore to the specific heat capacity of the formation, dimensionless; Accordingly, the calculation formula for calculating the gas mass flow rate in the production string according to the gas standard density and the gas production rate includes: In the formula, w f is the gas mass flow rate in the production column, kg / s; Q is the gas production rate, m 3 / d;ρ s is the standard density of the gas, kg / m 3 ; Accordingly, the calculation formula for calculating the corresponding gas temperature in the first sub-production string according to the dimensionless formation temperature, the gas mass flow rate, the gas temperature in the previous first sub-production string, the first preset length, the formation thermal conductivity, the initial formation temperature corresponding to the first sub-production string, the gas specific heat capacity in the production string, and the radial heat transfer thermal resistance includes: Where, T f i is the gas temperature in the first sub-production column of the i-th section, °C; T D is the dimensionless formation temperature; T f i-1 is the gas temperature in the first sub-production string of the i-th section corresponding to the previous section, °C; h fd1 is the first preset length, m; λ e is the formation thermal conductivity, W / (m·℃); T e i The initial formation temperature corresponding to the first sub-production string of the i-th section, °C; w f is the gas mass flow rate in the production string, kg / s; C f is the specific heat capacity of the gas in the production column, J / (kg·℃); R to i is the radial heat transfer resistance of the i-th wellbore segment with length △z, m·℃ / W; Accordingly, the calculation formula for calculating the gas density in each first sub-production string according to the gas temperature in each first sub-production string, the pressure in each first sub-production string, the standard temperature, the standard pressure and the standard density of the gas includes: In the formula, is the gas density in the first sub-production string of the i-1 section, kg / m 3 ; T f i-1 is the gas temperature in the first sub-production string corresponding to the i-1th section; P i-1 is the pressure in the first sub-production string of the i-1th section, MPa; T s is the standard temperature, °C; p s is the standard pressure, MPa; ρ s is the standard density of the gas, kg / m 3 ; Accordingly, the calculation formula for calculating the gas flow rate in each first sub-production string according to the gas density in each first sub-production string, the gas production rate and the gas standard density includes: In the formula, is the gas flow rate in the first sub-production string of the i-1th section, m / s; Q is the gas production rate, m 3 / d;ρ s is the standard density of the gas, kg / m 3 ;d tn is the inner diameter of the production string, m; is the gas density in the first sub-production string of the i-1 section, kg / m 3 ; Accordingly, the calculation formula for calculating the friction coefficient of each first sub-production string according to the roughness of the production string, the gas viscosity in the production string, the inner diameter of the production string, the gas density in each first sub-production string, and the gas flow rate in each first sub-production string includes: In the formula, f i-1 is the friction coefficient of the first sub-production string of the i-1th section, dimensionless; Ra is the roughness of the production string, m; μ is the gas viscosity in the production string, Pa·s; is the gas density in the first sub-production string of the i-1 section, kg / m 3 ; is the gas flow rate in the first sub-production string of the i-1th section, m / s; d tn i is the inner diameter of the first sub-production string of the i-th section, m; Accordingly, the calculation formula for calculating the pressure in each first sub-production string according to the friction coefficient of each first sub-production string, the gas density in each first sub-production string, the first preset length, the inner diameter of the production string, and the gas flow rate in each first sub-production string includes: In the formula, is the pressure in the first sub-production string corresponding to the i-th section; is the pressure in the first sub-production string corresponding to the i-1th section; h fd1 is the first preset length, m; Gas density in the first sub-production string of section i-1, kg / m 3 ;f i-1 is the friction coefficient of the first sub-production string of the i-1th section, dimensionless; is the gas flow rate in the first sub-production string of the i-1th section, m / s; d tn is the inner diameter of the production string, m.

7. The method according to claim 1, characterized in that The determining the throttled production string pressure and throttled production string temperature corresponding to the production string includes: Determine the gas compressibility factor of the production string according to the pressure in the first sub-production string when blockage is not considered, the temperature in the first sub-production string when blockage is not considered, and the relative density of the gas; Calculate the gas production rate under critical throttling according to the gas compression factor of the production string, the pressure in the first sub-production string when blockage is not considered, the throttling hole area of ​​the production string, the adiabatic index of the leaked gas, the gas molar mass, the gas constant and the temperature in the first sub-production string when blockage is not considered; judging whether the production string is in a critical throttling state according to the gas production rate and the gas production rate; If the production string is in a critical throttling state, the pressure of the production string after throttling is calculated according to the pressure in the first sub-production string without considering blockage and the adiabatic index of the leaked gas; If the production string is not in a critical throttling state, the pressure ratio before and after throttling is calculated according to the adiabatic index of the leaking gas, the gas production rate, the gas standard density, the pressure in the first sub-production string when blockage is not considered, the throttling hole area of ​​the production string, the gas compression factor, the gas constant, the temperature in the first sub-production string when blockage is not considered, and the gas molar mass; Calculating the pressure of the production string after throttling according to the pressure ratio before and after throttling and the pressure in the first sub-production string when blockage is not considered; The temperature of the production string after throttling is calculated according to the production string pressure after throttling, the compression factor before throttling, the compression factor after throttling, the pressure in the first sub-production string when blockage is not considered, the adiabatic index of the leaked gas, and the temperature in the first sub-production string when blockage is not considered.

8. The method according to claim 7, characterized in that The calculation formula for determining the gas compressibility factor of the production string based on the pressure in the first sub-production string without considering blockage, the temperature in the first sub-production string without considering blockage, and the relative density of gas includes: In the formula, Z g is the gas compression factor, dimensionless; A1, A2, A3, A4, A5, A6, A7, A8, A9, A 10 is a constant, dimensionless, and is 1.1153, -0.079, 0.01588, 0.00886, -2.1619, 1.1575, -0.05368, 0.014655, -1.80997, 0.9548 respectively; p fL is the pressure in the first sub-production string without considering blockage, MPa; γ g is the relative density of the gas, dimensionless; p r is the quasi-comparison pressure, an intermediate quantity, dimensionless; T r is the temperature to be compared, an intermediate quantity, dimensionless; T fL is the temperature in the first sub-production string without considering blockage, °C; Accordingly, the calculation formula for calculating the gas production rate under critical throttling conditions according to the gas compression factor of the production string, the pressure in the first sub-production string when blockage is not considered, the throttling hole area of ​​the production string, the adiabatic index of the leaking gas, the gas molar mass, the gas constant, and the temperature in the first sub-production string when blockage is not considered includes: In the formula, Q Lg is the gas production rate under critical throttling conditions, m 3 / d;p fL A is the pressure in the first sub-production string without considering blockage, MPa; L is the throttling hole area of ​​the production string, m2; ρ s is the standard density of the gas, kg / m 3 ; Zg is the gas compressibility factor, dimensionless; R is the gas constant, taken as 8.3414; M g is the gas molar mass, kg / mol; T fL is the temperature in the first sub-production string without considering blockage, °C; k g is the adiabatic index of the leaking gas, which is 1.66 and dimensionless; Accordingly, the calculation formula for judging whether the production string is in a critical throttling state according to the gas production rate and the gas production rate includes: Where Q is the gas production rate, m 3 / d;Q Lg is the gas production rate under critical throttling conditions, m 3 / d; E1 is the error, dimensionless; Accordingly, the calculation formula for calculating the pressure of the production string after throttling based on the pressure in the first sub-production string without considering blockage and the adiabatic index of the leaked gas includes: Where P J is the production string pressure after throttling; k g is the adiabatic index of the leaking gas, which is 1.66 and dimensionless; p fL is the pressure in the first sub-production string without considering blockage, MPa; Accordingly, the calculation formula for calculating the pressure ratio before and after throttling according to the adiabatic index of the leaking gas, the gas production rate, the gas standard density, the pressure in the first sub-production string when blockage is not considered, the throttling hole area of ​​the production string, the gas compression factor, the gas constant, the temperature in the first sub-production string when blockage is not considered, and the gas molar mass includes: Where, C is the pressure ratio before and after throttling, dimensionless, C is less than 1; Q is the gas production rate, m 3 / d;ρ s is the standard density of the gas; p fL A is the pressure in the first sub-production string without considering blockage, MPa; L is the throttling hole area of ​​the production string, m2; k g is the adiabatic index of the leaking gas, which is 1.66 and dimensionless; Z g is the gas compression factor, dimensionless; R is the gas constant, taken as 8.3414; T fL is the temperature in the first sub-production string without considering blockage, °C; M g is the molar mass of the gas, kg / mol; Accordingly, the calculation formula for calculating the pressure of the production string after throttling based on the pressure ratio before and after throttling and the pressure in the first sub-production string without considering blockage includes: Where P J is the pressure of the production string after throttling; C is the pressure ratio before and after throttling, dimensionless, C is less than 1; p fL is the pressure in the first sub-production string without considering blockage, MPa; Accordingly, the method of calculating the temperature of the production string after throttling according to the production string pressure after throttling, the compression factor before throttling, the compression factor after throttling, the pressure in the first sub-production string when blockage is not considered, the adiabatic index of the leaked gas, and the temperature in the first sub-production string when blockage is not considered includes: Where, T J is the temperature after throttling, ℃; Z fL is the compression factor before throttling, dimensionless; Z J is the compression factor after throttling, dimensionless; P J is the production string pressure after throttling; p fL is the pressure in the first sub-production string without considering blockage, MPa; k g is the adiabatic index of the leaking gas, which is 1.66 and dimensionless; T fL is the temperature inside the first sub-production string without considering blockage, ℃.

9. The method according to claim 1, characterized in that: The step of judging whether the production string meets the collapse condition according to the dynamic pressure in the first sub-production string and the wellhead calculated pressure includes: Determining whether the wellhead calculated pressure and the wellhead measured pressure satisfy a first preset error; If the wellhead calculated pressure and the wellhead measured pressure satisfy a preset error, then determining that the wellhead calculated pressure and the wellhead measured pressure are equal; Calculating the collapse pressure of the production string according to the initial annulus pressure, the annulus gas density, the gravitational acceleration, the annulus liquid density, the collapse depth and the annulus liquid depth; Determining whether the dynamic pressure in the first sub-production string and the collapse pressure satisfy a second preset error; If the dynamic pressure in the first sub-production string and the collapse pressure satisfy a second preset error, determining that the dynamic pressure in the first sub-production string and the collapse pressure are equal; If the wellhead calculated pressure and the wellhead measured pressure are equal, and the dynamic pressure in the first sub-production string and the collapse pressure are equal, then it is determined that the production string meets the collapse condition; if the wellhead calculated pressure and the wellhead measured pressure are not equal, and / or the dynamic pressure in the first sub-production string and the collapse pressure are not equal, then it is determined that the production string does not meet the collapse condition.

10. The method according to claim 9, characterized in that The calculation formula for determining whether the wellhead calculated pressure and the wellhead measured pressure satisfy the first preset error includes: In the formula, Calculate the pressure at the wellhead; p w2 is the wellhead measured pressure; E is the first preset error; Accordingly, the calculation of the collapse pressure of the production string according to the initial annulus pressure, the annulus gas density, the gravitational acceleration, the annulus liquid density, the collapse depth and the annulus liquid depth comprises: Where P tw is the collapse pressure of the production string, MPa; p an is the initial annular pressure, MPa; ρ ga is the annular gas density, kg / m 3 ; g is the acceleration due to gravity; ρ L is the density of the annular liquid, kg / m 3 ;h cc is the crush depth, m; h g is the annulus liquid depth, m; Accordingly, the calculation formula for judging whether the dynamic pressure in the first sub-production string and the collapse pressure satisfy the second preset error includes: In the formula, is the anti-external collapse strength of the oil pipe, MPa; P tw is the collapse pressure of the production string, MPa; is the dynamic pressure in the first sub-production string; 1.0 is the second preset error.

11. The method according to any one of claims 1 to 10, characterized in that: The obtaining of initial operating parameters of the wellbore and judging whether the production tubing in the wellbore is leaking or crushed according to the initial operating parameters include: Acquiring operating parameters of a wellbore, wherein the wellbore at least includes a wellhead, an oil casing annulus and a production string; the operating parameters at least include annular pressure of the oil casing annulus, wellhead oil pressure and pressure in the production string; Determining whether the production tubing string is leaking according to the annulus pressure and the wellhead oil pressure; If it is determined that the production string is leaking, determining whether the production string is blocked according to the pressure inside the production string, the annulus pressure and the wellhead oil pressure; If it is determined that the production tubing string is blocked, it is determined that the production tubing string is collapsed.

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