Algorithm for converting rod-pumped well reaction force ratio method into working fluid level

Abstract

The invention provides an algorithm for converting a working fluid level through a rod-pumped well reaction ratio method. The algorithm mainly solves the problem that according to an existing calculation method, the number of static parameters is large, and the working fluid level calculation precision is low due to the large influence of human factors. The method is characterized by comprising the following steps that S1, a working fluid level conversion algorithm model is established on the basis of a polished rod load theoretical calculation formula in combination with counter-force ratio definition; s2, on the basis of the established working fluid level conversion algorithm model, field actual measurement data and needed static data are obtained in real time, and converted working fluid level data are determined through calculation; and S3, comparing the calculated converted dynamic liquid level data with the dynamic liquid level actually measured by the field sound wave method, evaluating according to a certain error standard, and verifying the converted precision of the converted dynamic liquid level algorithm. According to the rod-pumped well reaction ratio method converted working liquid level algorithm, the reaction ratio method calculation algorithm is adopted, interference of human factors is small, and the calculation algorithm is simple, high in speed and high in precision.

Description

Technical Field

[0001] The invention relates to the technical field of oil production engineering, and in particular to an algorithm for converting a dynamic liquid level using a reaction force ratio method for a pumping well. Background Art

[0002] The pumping well performance diagram and dynamic liquid level are important indicators for diagnosing the working conditions of the pumping well, discovering production anomalies, and mastering production dynamics. They need to be manually tested and recorded regularly. At present, they mainly rely on comprehensive testers for manual testing and interpretation. The comprehensive tester is a low-pressure well testing instrument, which includes two parts: a dynamometer and an echometer.

[0003] The operation process of the dynamometer and dynamic liquid level test is complex, labor-intensive, and requires high human and material resources. The safety and environmental protection requirements for wellhead explosion-proof, leak-proof, and blowout-proof are high, and there are human operation errors. For example, the cycle of the dynamometer and dynamic liquid level test for a single well in Daqing Oilfield has been 20 to 40 days for many years, resulting in a delay of more than half a month in the discovery and handling of some problems. Therefore, it is urgent to shorten the test cycle to meet the needs of safe, efficient, and lean development of oilfields.

[0004] By using the theoretical calculation formula of the suspension load, the dynamic liquid level value can be directly calculated when the upward load and various static parameters are determined. However, if there are too many calculation parameters and the accuracy of one parameter is inaccurate, errors will occur. If the errors of dozens of data are superimposed, the error of the final calculation result will be further amplified. At the same time, the dynamic load in the above formula is not fully considered, such as vibration load, load generated by wellhead back pressure, etc., and the accurate calculation formula of friction load is even more difficult to determine. Direct measurement will inevitably produce large errors, and a large amount of data overflow will occur. Summary of the invention

[0005] The technical problem to be solved by the present invention is to overcome the problem that the existing calculation method in the background technology has many static parameters and is greatly affected by human factors, resulting in low accuracy in calculating the dynamic liquid level, and to provide an algorithm for calculating the dynamic liquid level using the reaction force ratio method for a pumping well. The algorithm for calculating the dynamic liquid level using the reaction force ratio method adopts a calculation algorithm using the reaction force ratio method, is less affected by human factors, has a simple calculation algorithm, is fast, and has high accuracy.

[0006] The present invention solves the problem through the following technical solution: the algorithm for calculating the dynamic liquid level using the reaction force ratio method of the pumping well includes the following steps:

[0007] S1. Based on the theoretical calculation formula of the suspension point load and the definition of the reaction force ratio, a dynamic liquid surface conversion algorithm model is established;

[0008] S2. Based on the established dynamic liquid level conversion algorithm model, the field measured data and the required static data are obtained in real time, and the converted dynamic liquid level data is determined by calculation;

[0009] S3. Compare the calculated dynamic liquid level data with the dynamic liquid level actually measured by the on-site acoustic wave method, evaluate it according to a certain error standard, and verify the accuracy of the dynamic liquid level conversion algorithm.

[0010] Furthermore, the method of establishing the dynamic liquid level conversion algorithm model in step S1 comprises the following steps:

[0011] 101. By calculating the theoretical formula of the suspension point load, it is determined that both the upward load and the downward load are linear functions of the pump depth;

[0012] Combined with the relationship between pump depth and the sum of submergence and dynamic liquid surface, the theoretical calculation formula of suspension point load is simplified into a linear function of suspension point upward load, suspension point downward load and pump depth;

[0013] 102. According to the definition of lifting height and the simplified linear function relationship between the upward load of the suspension point, the downward load of the suspension point and the pump depth, the proportion of the lifting liquid column load to the upward load is obtained. Since the proportion of the lifting liquid column load to the upward load is the same as the ratio of the lifting height to the pump depth, the ratio of the lifting height to the pump depth can be obtained, and thus the lifting height can be obtained;

[0014] 103. Based on the definition of dynamic liquid surface, the pressure head formula of oil-casing pressure difference is obtained; through the theoretical calculation formula of suspension point load, the relationship between dynamic load and stroke, stroke frequency and buoyancy coefficient can be determined, and the concept of reaction force ratio is introduced, and the ratio of the downward load of the suspension point to the upward load of the suspension point is defined as the reaction force ratio;

[0015] Because the filling degree of the pump is also one of the factors that affect the dynamic liquid level; after deduction, the formula for calculating the reaction force ratio considering the pump barrel is full is determined;

[0016] 104. The relationship between dynamic load and stroke, stroke frequency and buoyancy coefficient and the concept of reaction force ratio are combined with the pressure head formula of oil-casing pressure difference and the proportion of lifting liquid column load to upward load to obtain the dynamic liquid level formula; combined with the factor of pump barrel filling, the reaction force ratio formula is replaced by the reaction force ratio formula to obtain the final converted dynamic liquid level formula, which is the dynamic liquid level conversion algorithm model of the working well.

[0017] Furthermore, the theoretical calculation formula of the suspension point load in step S101 is:

[0018]

[0019]

[0020]

[0021] H D =H B -H C (Formula 4)

[0022] Where: P u , P D ——Upward load of suspension point, downward load of suspension point, KN;

[0023] D P , D G ,D T ,D Y ——Pump diameter, rod diameter, casing inner diameter, tubing outer diameter, mm;

[0024] γ 液 , γ 钢 ,γ O ——Liquid specific gravity, steel specific gravity 7.47, oil specific gravity 0.83;

[0025] g——acceleration due to gravity 9.8, N / kg;

[0026] H B ,H C ,H D ——Pump depth, submergence, dynamic liquid level, m;

[0027] f w ——Water content in daily reports, in percentage;

[0028] b——the buoyancy coefficient of the rod in the liquid column;

[0029] S——stroke of the pumping well, m;

[0030] n——the number of strokes of the pumping well in operation, times / min.

[0031] Furthermore, the simplified linear function formulas of the suspension point upward load, the suspension point downward load and the pump depth in step S101 are respectively:

[0032] P U =AH B +BH B +CH B (Formula 5)

[0033] P D =AH B -CH B (Formula 6)

[0034] In the formula: A, B, C are the load constants of the rod in the liquid column, the load constant of the lifting liquid column, and the inertia load constant.

[0035] Furthermore, the lifting height definition formula in step S102 is:

[0036]

[0037] Where:

[0038] H J ——Calculated lifting height of the pumping well, m.

[0039] Furthermore, the step S103 obtains the pressure head formula of the oil-casing pressure difference based on the definition of the dynamic liquid surface:

[0040]

[0041] Where: T T ,T O ——Well casing pressure of pumping unit, oil pressure, MPa;

[0042] The dynamic load CH can be determined by the theoretical calculation formula of the suspension point load: B The relationship between stroke, stroke frequency and buoyancy coefficient is:

[0043]

[0044] The definition formula of reaction ratio is:

[0045]

[0046] Where: k——reaction ratio;

[0047] The formula for calculating the reaction force ratio considering the pump barrel is full;

[0048]

[0049] in:

[0050] η=S p / S (Formula 13)

[0051] Where: η- is the degree of pump filling;

[0052] k'-reduced reaction force ratio under the degree of underfilling;

[0053] S p -Effective stroke, m, is calculated by the effective stroke scanning interception method of the power diagram.

[0054] Furthermore, the dynamic liquid level formula obtained in step S104 is:

[0055]

[0056] Combined with the factor of the pump barrel being full, the reaction force ratio formula is replaced by the reaction force ratio formula to obtain the final converted dynamic liquid level formula:

[0057]

[0058] Furthermore, the specific method of step S2, obtaining the field measured data and the required static data in real time based on the established dynamic liquid level conversion algorithm model, and determining the converted dynamic liquid level data by calculation, includes:

[0059] S201, obtaining the upward load of the suspension point, the downward load of the suspension point, the measured stroke, and the measured stroke frequency through the work diagram collected in real time by the digital load sensor;

[0060] S202, obtaining wellhead oil pressure and casing pressure data in real time through a wellhead digital pressure gauge;

[0061] S203, calculating the rod column buoyancy influence coefficient b and the well fluid specific gravity through the artificially recorded water content;

[0062] S204, through the report, retrieve two static parameters of water content and pump hanging depth in real time;

[0063] S205, for wells with different working conditions, determine the pump filling degree; considering the pump filling degree, calculate the effective stroke by the work diagram effective stroke scanning interception method, and calculate the conversion reaction force ratio;

[0064] S206. After obtaining the measured data, static data and converted reaction force ratio required by the dynamic liquid level calculation algorithm through the above steps, the dynamic liquid level data is calculated through the final converted dynamic liquid level formula.

[0065] Furthermore, S3 compares the above-calculated dynamic liquid level data with the dynamic liquid level actually measured by the on-site acoustic wave method, and the error standard for evaluation is ±50m.

[0066] Furthermore, the method of comparing the above-calculated dynamic liquid level data with the dynamic liquid level actually measured by the on-site acoustic wave method, evaluating it according to a certain error standard, and verifying the accuracy of the dynamic liquid level conversion algorithm includes:

[0067] The converted dynamic liquid level is compared with the dynamic liquid level actually measured by the on-site acoustic wave method, and verified in wells with different working conditions and evaluated according to the error standard within ±50m; the different working conditions wells include normal wells, gas-affected wells, insufficient liquid supply wells, and disconnection and leakage wells;

[0068] Verify and determine under which working conditions the converted dynamic liquid level error can be controlled within the error standard;

[0069] Through verification, it is found that the pump barrel is filled to a high degree in normal wells and wells with disconnection and leakage, and the converted dynamic liquid level error can be controlled within the error standard;

[0070] Through verification, it is found that for wells affected by gas and insufficient liquid supply, the pump barrel is not filled to a low degree. The dynamic liquid level conversion algorithm formula when the pump barrel is not full is applied to determine whether the dynamic liquid level error of wells affected by gas and insufficient liquid supply can be controlled within the error standard.

[0071] The basic principle of the algorithm for calculating the dynamic liquid level using the reaction force ratio method of the pumping well of the present invention is as follows:

[0072] From the theoretical calculation formula of the suspension point load (Formula 1 to 4), it can be seen that the upward load and the downward load are both the pump depth H B The sum of the submergence and the dynamic liquid level is the pump depth. Therefore, when the static parameters such as the suspension point load, rod diameter, pump diameter, pipe diameter, and pump depth are determined, the dynamic liquid level value can be directly calculated.

[0073] However, the theoretical calculation formula for suspension load involves too many static parameters such as rods, pipes, and pumps. If the accuracy of one parameter is inaccurate, errors will occur. The more static parameters there are, the more data errors will be superimposed and amplified, which will further amplify the errors in the final calculation results. At the same time, the dynamic loads in the theoretical formula are not fully considered, such as vibration loads and loads generated by wellhead back pressure. The precise calculation formula for friction loads is even more difficult to determine. Direct measurement will inevitably produce large errors, and a large amount of data overflow will occur. That is, the method of direct calculation through theoretical formulas is not advisable. It is necessary to reduce the number of static parameters involved in the calculation, eliminate the influence of irrelevant parameters, and improve the conversion accuracy.

[0074] According to the above analysis, the upward and downward loads of the suspension point are both linear functions of the pump depth. As can be seen from Formula 1, the upward load of the suspension point is the sum of the static load of the rod column, the lifting liquid column load, and the dynamic load, which together lift the well fluid from the pump end to the wellhead. Among them, the static load of the rod column is a linear function of the pump depth; the dynamic load is the sum of the inertia load and the friction resistance of the rod column, which is also a linear function of the pump depth; the lifting liquid column load is the difference between the liquid column load above the pump and the sinking pressure generated by the liquid column in the casing annulus, that is, the load generated by the lifting height, which is also a linear function of the pump depth. In summary, it can be understood that the upward load of the suspension point is the sum of the pressure heads consumed by the three loads, that is, the sum of the pressure heads consumed by the static load of the rod column, the lifting liquid column load and the dynamic load (see Formula 5 and Formula 6 for details), and the total pressure head is the pump depth. Therefore, as long as the proportion of the lifting liquid column load to the upward load is calculated (Formula 7), the ratio of the lifting height to the pump depth can be obtained. The pump depth is known, so the lifting height can be obtained, combined with the pressure head of the oil-casing pressure difference, to obtain the dynamic liquid level.

[0075] According to formulas 1 to 3, the dynamic load CH is derived B is the relationship between stroke, stroke frequency and buoyancy coefficient (Formula 9). Substituting Formula 9 and Formula 10 into Formula 7 and Formula 8, we get the dynamic liquid surface calculation formula (Formula 11). In the calculation process, the concept of reaction force ratio (Formula 10) is introduced, that is, the ratio of the downward load of the suspension point to the upward load of the suspension point (defined by the relative force ratio, the force ratio is the ratio of the upward load of the suspension point to the downward load of the suspension point), which effectively simplifies the calculation process and is of great significance in the process of working condition diagnosis and boundary condition setting.

[0076] Verification method of the algorithm for calculating the dynamic liquid level using the reaction force ratio method of the pumping well of the present invention:

[0077] In order to verify and improve the conversion accuracy of the dynamic liquid level conversion algorithm, the dynamic liquid level measured by the on-site acoustic wave method was compared and evaluated according to the error standard within ±50m. The wells with different working conditions such as normal, gas-affected, insufficient liquid supply, and disconnection and leakage were verified respectively. Through verification, the dynamic liquid level error converted under various working conditions can basically be controlled within ±50m. However, there are also a few wells with errors exceeding ±50m, mainly gas-affected and insufficient liquid supply wells. After comparative analysis, the pump filling degree is also one of the factors affecting the dynamic liquid level. The low filling degree indicates that there is less liquid entering the plunger, and the upward load is actually missing a part, which needs to be increased, that is, the reaction force ratio needs to be reduced and converted, and the reduced part is the load of the liquid column that is not filled. After derivation, the conversion reaction force ratio when the pump barrel is not full is formula 12. Therefore, after substituting formula 12 into formula 11, the final dynamic liquid level conversion algorithm is formed (see formula 14). When the filling degree is equal to 1, the calculation formula is consistent with the original formula 11, which effectively meets the dynamic liquid level conversion requirements under various working conditions.

[0078] Compared with the above background technology, the present invention has the following beneficial effects:

[0079] With the large-scale promotion of digital oil fields, load sensors are installed in all pumping wells to realize the real-time acquisition of the suspension point load of the bare rod indicator diagram of the pumping well. The liquid level test still requires manual testing with an echo sounder. However, according to the theoretical analysis of the suspension point load of the bare rod indicator diagram of the pumping well, the suspension point load is positively correlated with the dynamic liquid level, and the indicator diagram can be used to convert the dynamic liquid level, thereby replacing the manual test of the dynamic liquid level. Therefore, this paper uses the suspension point load of the indicator diagram collected in real time by digitalization, derives and verifies the mathematical model algorithm of the suspension point load and the dynamic liquid level, studies and applies the algorithm for converting the dynamic liquid level based on the reaction force ratio method of the pumping well, achieves the purpose of real-time conversion of the dynamic liquid level, and realizes real-time and accurate dynamic analysis of the pumping well.

[0080] The dynamic liquid level conversion algorithm of the reaction force ratio method of the pumping well of the present invention has good stability and strong operability. The unique reaction force ratio dynamic liquid level conversion algorithm eliminates the problems of many static parameters and great influence of human factors, and successfully realizes the dynamic liquid level conversion of the pumping well using the work diagram. The absolute value error of a single well is within ±50m, and the comparison accuracy meets the needs of oil field testing and production, providing strong technical support for replacing more than 80% of the workload of manual dynamic liquid level testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0081] Figure 1 Real-time acquisition of work diagram for well B2-1-645 in Example of the present invention;

[0082] Figure 2 The dynamic liquid level measured by the echo sounder of well B2-1-645 in Example of the present invention;

[0083] Figure 3 Real-time acquisition of work diagram for well B3-362-P41 in the embodiment of the present invention;

[0084] Figure 4 The dynamic liquid level measured by the echo sounder of well B3-362-P41 in Example of the present invention;

[0085] Figure 5 Real-time acquisition of work diagram for well B2-2-X42 in the embodiment of the present invention;

[0086] Figure 6 The dynamic liquid level measured by the echo sounder of well B2-2-X42 in the embodiment of the present invention;

[0087] Figure 7 Real-time acquisition of work diagram for well B2-D1-41 in the embodiment of the present invention;

[0088] Figure 8 The dynamic liquid level measured by the echo sounder of well B2-D1-41 in Example 1 of the present invention;

[0089] Fig. 9 Real-time acquisition of work diagram for well B2-310-P46 in the embodiment of the present invention;

[0090] Fig.10 The dynamic liquid level measured by the echo sounder of well B2-310-P46 in Example of the present invention;

[0091] Fig.11 This is a block diagram of the algorithm for converting the dynamic liquid level using the reaction force ratio method of the pumping well of the present invention. DETAILED DESCRIPTION

[0092] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0093] like Fig.11 As shown, the present invention discloses an algorithm for calculating the dynamic liquid level using the reaction force ratio method of a pumping well, comprising the following steps:

[0094] S1. Based on the theoretical calculation formula of the suspension point load and the definition of the reaction force ratio, a dynamic liquid surface conversion algorithm model is established;

[0095] 101. By using the theoretical calculation formula of the suspension point load, it is determined that both the upward load and the downward load are linear functions of the pump depth; combined with the relationship between the pump depth and the sum of the submergence and the dynamic liquid surface; the theoretical calculation formula of the suspension point load is simplified to a linear function of the suspension point upward load, the suspension point downward load and the pump depth (Formula 5-6);

[0096] The theoretical calculation formula for the suspension point load is:

[0097]

[0098]

[0099]

[0100] H D =H B -H C (Formula 4)

[0101] Where: P u , P D ——Upward load of suspension point, downward load of suspension point, KN;

[0102] D P , D G ,D T ,D Y ——Pump diameter, rod diameter, casing inner diameter, tubing outer diameter, mm;

[0103] γ 液 , γ 钢 ,γ O ——Liquid specific gravity, steel specific gravity 7.47, oil specific gravity 0.83;

[0104] g——acceleration due to gravity 9.8, N / kg;

[0105] H B ,H C ,H D ——Pump depth, submergence, dynamic liquid level, m;

[0106] f w ——Water content in daily reports, in percentage;

[0107] b——the buoyancy coefficient of the rod in the liquid column;

[0108] S——stroke of the pumping well, m;

[0109] n——the number of strokes of the pumping well in operation, times / min.

[0110] The simplified linear function formulas of the suspension point upward load, suspension point downward load and pump depth in step S101 are (Formulas 5-6):

[0111] P U =AH B +BH B +CH B (Formula 5)

[0112] P D =AH B -CH B(Formula 6)

[0113] In the formula: A, B, C are the load constants of the rod in the liquid column, the load constant of the lifting liquid column, and the inertia load constant.

[0114] 102. According to the definition of lifting height and the simplified linear function relationship between the upward load of the suspension point, the downward load of the suspension point and the pump depth, the proportion of the lifting liquid column load to the upward load is obtained (Formula 7). Since the proportion of the lifting liquid column load to the upward load is the same as the ratio of the lifting height to the pump depth, the ratio of the lifting height to the pump depth can be obtained, and thus the lifting height can be obtained;

[0115] The lifting height HJ is defined by the formula:

[0116]

[0117] Where:

[0118] H J ——Calculated lifting height of the pumping well, m.

[0119] 103. Based on the definition of dynamic liquid level, the pressure head formula of the oil-casing pressure difference is obtained 8; the dynamic load CH can be determined by the theoretical calculation formula of the suspension point load B The relationship between the stroke, stroke frequency and buoyancy coefficient (Formula 9) is introduced, and the concept of reaction force ratio is defined as the ratio of the downward load of the suspension point to the upward load of the suspension point (Formula 10). Since the filling degree of the pump is also one of the factors affecting the dynamic liquid surface, the conversion reaction force ratio formula considering the fullness of the pump barrel is determined through derivation (Formula 12).

[0120] The pressure head formula 8 for obtaining the oil-casing pressure difference is:

[0121]

[0122] Where: T T ,T O ——Well casing pressure of pumping unit, oil pressure, MPa;

[0123] The dynamic load CH can be determined by the theoretical calculation formula of the suspension point load: B The formula 9 related to stroke, stroke frequency and buoyancy coefficient is:

[0124]

[0125] The definition formula of reaction force ratio is 10:

[0126]

[0127] Where: k——reaction ratio;

[0128] The formula for calculating the reaction force ratio considering the pump barrel is full;

[0129]

[0130] in:

[0131] η=S p / S (Formula 13)

[0132] Where: η- is the degree of pump filling;

[0133] k'-reduced reaction force ratio under the degree of underfilling;

[0134] S p -Effective stroke, m, is calculated by the effective stroke scanning interception method of the power diagram.

[0135] 104. Dynamic load CH B The relationship between stroke, stroke frequency and buoyancy coefficient and the concept of reaction force ratio are combined with the pressure head formula 8 of the oil-casing pressure difference and the proportion of the lifting liquid column load to the upward load 7 to obtain the dynamic liquid level formula 11; combined with the factor of the pump barrel being full, the reaction force ratio formula is replaced by the reaction force ratio formula to obtain the final converted dynamic liquid level formula, which is the dynamic liquid level conversion algorithm model for the working well.

[0136] The dynamic liquid level formula 11 is:

[0137]

[0138] Combined with the factor of the pump barrel being full, the reaction force ratio formula is replaced by the reaction force ratio formula to obtain the final converted dynamic liquid level formula:

[0139]

[0140] S2. Based on the established dynamic liquid level conversion algorithm model, the field measured data and the required static data are obtained in real time, and the specific method of determining the converted dynamic liquid level data by calculation includes:

[0141] S201, obtaining the upward load of the suspension point, the downward load of the suspension point, the measured stroke, and the measured stroke frequency through the work diagram collected in real time by the digital load sensor;

[0142] Through the work diagram load sensor collection, the load and acceleration sensor are integrated and installed at the end of the rope hanger to synchronously collect load and displacement to form a work diagram; it is divided into wired and battery powered, and wireless remote transmission is performed every 10mn;

[0143] S202, obtaining wellhead oil pressure and casing pressure data in real time through a wellhead digital pressure gauge;

[0144] The oil pressure is collected by the pressure sensor, which can be digitally displayed on site. It is installed on the crude oil pressure tapping port of the Christmas tree, with a pressure resistance of 10MPa. It is powered by wired or battery, and can be wirelessly transmitted every 10 minutes.

[0145] S203, calculating the rod column buoyancy influence coefficient b and the well fluid specific gravity through the artificially recorded water content;

[0146] S204, through the report, retrieve two static parameters of water content and pump hanging depth in real time;

[0147] S205, for wells with different working conditions, determine the pump filling degree; considering the pump filling degree, calculate the effective stroke by the work diagram effective stroke scanning interception method, and calculate the conversion reaction force ratio;

[0148] S206. After obtaining the measured data, static data and converted reaction force ratio required by the dynamic liquid level calculation algorithm through the above steps, the dynamic liquid level data is calculated through the final converted dynamic liquid level formula.

[0149] S3. Compare the above calculated dynamic liquid level data with the dynamic liquid level actually measured by the on-site acoustic wave method, evaluate according to certain error standards, and verify the accuracy of the dynamic liquid level conversion algorithm; the specific method includes:

[0150] The converted dynamic liquid level is compared with the dynamic liquid level actually measured by the on-site acoustic wave method, and verified in wells with different working conditions and evaluated according to the error standard within ±50m; the different working conditions wells include normal wells, gas-affected wells, insufficient liquid supply wells, and disconnection and leakage wells;

[0151] Verify and determine under which working conditions the converted dynamic liquid level error can be controlled within the error standard;

[0152] Through verification, the dynamic liquid level error of normal wells and wells with disconnection and leakage can be controlled within the error standard;

[0153] Through verification, it is found that for wells affected by gas and insufficient liquid supply, the filling degree of the pump barrel is low. Through comparative verification and analysis, it is determined that the filling degree of the pump is also one of the factors affecting the dynamic liquid level; through derivation, the formula for calculating the reaction force ratio when the pump barrel is not full is determined;

[0154] Thus, the dynamic liquid level conversion algorithm formula when the pump barrel is not full is determined, and the dynamic liquid level error of the well affected by gas and insufficient liquid supply can be controlled within the error standard.

[0155] When the pumping well is disconnected or leaking, the maximum load becomes smaller, the reaction force ratio k becomes larger, and the calculated dynamic liquid level value becomes smaller. When it becomes smaller to a certain extent, the calculated dynamic liquid level will be negative, and the actual dynamic liquid level value will not be less than 0. Therefore, the boundary condition is set, that is, when the calculated dynamic liquid level value H D <0, H D =0.

[0156] Taking a certain area of ​​Sabei development in Daqing Oilfield as an example, the real-time acquisition of well power diagrams and casing pressure data of the pumping unit is used, combined with the static data of water content and pump depth, and the dynamic liquid level calculation formula is used to calculate the dynamic liquid level in real time. The dynamic liquid level calculated by the reaction force ratio method is compared with the dynamic liquid level tested on site by the synchronous artificial echo sounder to verify the accuracy of the dynamic liquid level calculated by the reaction force ratio method.

[0157] Example 1

[0158] The working condition of this area is the normal B2-1-645 well. The dynamic liquid level calculated by the reaction ratio method is 641.49m; the dynamic liquid level tested on-site by the synchronous artificial echo sounder is 642.28m, with an error of -0.79m. The selected parameter values ​​are shown in Table 1; Figure 1 Real-time acquisition of performance diagrams for B2-1-645 well, Figure 2 This is the result of the dynamic liquid level measured by the echo sounder in the B2-1-645 well.

[0159] Example 2

[0160] The working condition of this area is the disconnected B3-362-P41 well. The dynamic liquid level calculated by the reaction ratio method is 0m. The dynamic liquid level tested on-site by the synchronous artificial echo sounder is 0m, and the error is 0m. The selected parameter values ​​are shown in Table 1; Figure 3 Real-time acquisition of performance diagrams for the B3-362-P41 well, Figure 4 This is the result of the dynamic liquid level measured by the echo sounder in the B3-362-P41 well.

[0161] Example 3

[0162] The working condition of this area is the potential well B2-2-X42 well. On March 14, 2023, the dynamic liquid level calculated by the reaction ratio method was 307.31m, and the dynamic liquid level tested on site by the synchronous artificial echo sounder was 279.5m, with an error of 27.81m. The selected parameter values ​​are shown in Table 1; Figure 5 Real-time acquisition of performance diagrams for the B2-2-X42 well, Figure 6 The results of the dynamic liquid level measured by the echo sounder in the B2-2-X42 well.

[0163] Example 4

[0164] The working condition of this area is the gas-affected B2-D1-41 well. On April 4, 2023, the dynamic liquid level was calculated to be 736.04m using the reaction ratio method, and the dynamic liquid level was 758.76m in the field test of the synchronous artificial echo sounder, with an error of -22.72m. The selected parameter values ​​are shown in Table 1; Figure 7 Real-time acquisition of power diagrams for B2-D1-41 well, Figure 8 This is the result of the dynamic liquid level measured by the echo sounder in well B2-D1-41.

[0165] Example 5

[0166] In the B2-310-P46 well, which has insufficient fluid supply in this area, the dynamic liquid level was calculated to be 712.68m by the reaction ratio method on April 22, 2023. The dynamic liquid level tested on site by the echometer on the same day was 688.79m, with an error of 23.89m. The values ​​of each parameter are selected as shown in Table 1; Fig. 9 Real-time acquisition of power diagrams for the B2-310-P46 well, Fig.10 This is the result of the dynamic liquid level measured by the echo sounder in the B2-310-P46 well.

[0167] Table 1 Statistical table of calculation results of the reaction ratio method used in the implementation well

[0168]

[0169] In summary, for various common working conditions in oil fields, the error between the dynamic liquid level calculated by this algorithm and the dynamic liquid level tested on-site by the echo sounder acoustic wave method can be controlled within ±50m, which reflects a good on-site application effect. It has been promoted and applied in the operating area.

[0170] Comparative Example

[0171] For example, in a certain well A, the dynamic liquid level was calculated to be 1023.6m through direct settlement using theoretical formulas, but the actual measurement was only 573m, with a huge difference in error. Moreover, below the pump depth of 121.27m, the well fluid could not enter the pump barrel to produce liquid, and the data overflowed. That is, the method of direct calculation using theoretical formulas is not advisable. It is necessary to reduce the number of static parameters involved in the calculation, eliminate the influence of irrelevant parameters, and improve the conversion accuracy. Table 2 shows the situation of a certain well A using the method of direct calculation of the dynamic liquid level using loads.

[0172] Table 2 The situation of using the method of directly calculating the dynamic liquid level using load in a well A

[0173] Measured maximum load 57.41 Nissan Liquid 71.5 Pump diameter 70 Measured minimum load 20.29 Pump depth 902.33 Rod diameter 22 stroke 3.6 Rush 5.0 Water 98.2 Tube inner diameter 62 Casing inner diameter 139.7 Pipe outer diameter 73 Calculation of dynamic liquid level with alternating load 1023.6 Measured dynamic liquid level 578.13

[0174] It should be noted that the embodiments described above are only used to explain the present invention and do not constitute any limitation to the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory words, rather than restrictive words. The present invention may be modified as specified within the scope of the claims of the present invention, and the present invention may be revised without departing from the scope and spirit of the present invention. Therefore, the content of the present invention is not limited to the examples listed, and any equivalent changes taken by ordinary technicians in the field of the present invention by reading the specification of the present invention to the technical solution of the present invention are all covered by the claims of the present invention.

Claims

1. An algorithm for calculating the dynamic liquid level using the reaction force ratio method of a pumping well, characterized in that: The following steps are involved: S1. Based on the theoretical calculation formula of the suspension point load and the definition of the reaction force ratio, a dynamic liquid surface conversion algorithm model is established; S2. Based on the established dynamic liquid level conversion algorithm model, the field measured data and the required static data are obtained in real time, and the converted dynamic liquid level data is determined by calculation; S3. Compare the calculated dynamic liquid level data with the dynamic liquid level actually measured by the on-site acoustic wave method, evaluate it according to a certain error standard, and verify the accuracy of the dynamic liquid level conversion algorithm.

2. The algorithm for calculating the dynamic liquid level by the reaction force ratio method of the pumping well according to claim 1 is characterized in that: The method of establishing a dynamic liquid level conversion algorithm model in step S1 includes the following steps:

101. By calculating the theoretical formula of the suspension point load, it is determined that both the upward load and the downward load are linear functions of the pump depth; Combined with the relationship between pump depth and the sum of submergence and dynamic liquid surface, the theoretical calculation formula of suspension point load is simplified into a linear function of suspension point upward load, suspension point downward load and pump depth; 102. According to the definition of lifting height and the simplified linear function relationship between the upward load of the suspension point, the downward load of the suspension point and the pump depth, the proportion of the lifting liquid column load to the upward load is obtained. Since the proportion of the lifting liquid column load to the upward load is the same as the ratio of the lifting height to the pump depth, the ratio of the lifting height to the pump depth can be obtained, and thus the lifting height can be obtained; 103. Based on the definition of dynamic liquid surface, the pressure head formula of oil-casing pressure difference is obtained; through the theoretical calculation formula of suspension point load, the relationship between dynamic load and stroke, stroke frequency and buoyancy coefficient can be determined, and the concept of reaction force ratio is introduced, and the ratio of the downward load of the suspension point to the upward load of the suspension point is defined as the reaction force ratio; Because the filling degree of the pump is also one of the factors that affect the dynamic liquid level; after deduction, the formula for calculating the reaction force ratio considering the pump barrel is full is determined; 104. The relationship between dynamic load and stroke, stroke frequency and buoyancy coefficient and the concept of reaction force ratio are combined with the pressure head formula of oil-casing pressure difference and the proportion of lifting liquid column load to upward load to obtain the dynamic liquid level formula; combined with the factor of pump barrel filling, the reaction force ratio formula is replaced by the reaction force ratio formula to obtain the final converted dynamic liquid level formula, which is the dynamic liquid level conversion algorithm model of the working well.

3. The algorithm for calculating the dynamic liquid level by the reaction force ratio method of the pumping well according to claim 2 is characterized in that: The theoretical calculation formula of the suspension point load in step S101 is: H D =H B -H C (Formula 4) Where: P u , P D ——Upward load of suspension point, downward load of suspension point, KN; D P , D G ,D T ,D Y ——Pump diameter, rod diameter, casing inner diameter, tubing outer diameter, mm; γ 液 , γ 钢 ,γ O ——Liquid specific gravity, steel specific gravity 7.47, oil specific gravity 0.83; g——acceleration due to gravity 9.8, N / kg; H B ,H C ,H D ——Pump depth, submergence, dynamic liquid level, m; f w ——Water content in daily reports, in percentage; b——the buoyancy coefficient of the rod in the liquid column; S——stroke of the pumping well, m; n——the number of strokes of the pumping well in operation, times / min.

4. The algorithm for calculating the dynamic liquid level by the reaction force ratio method of the pumping well according to claim 1 is characterized in that: The simplified linear function formulas of the suspension point upward load, suspension point downward load and pump depth in step S101 are respectively: P U = AH B + BH B + CH B (Formula 5) P D =AH B -CH B (Formula 6) In the formula: A, B, C are the load constants of the rod in the liquid column, the load constant of the lifting liquid column, and the inertia load constant.

5. The algorithm for calculating the dynamic liquid level by the reaction force ratio method of the pumping well according to claim 1 is characterized in that: The lifting height definition formula in step S102 is: Where: H J ——Calculated lifting height of the pumping well, m.

6. The algorithm for calculating the dynamic liquid level by the reaction force ratio method of the pumping well according to claim 1 is characterized in that: The step S103 obtains the pressure head formula of the oil-casing pressure difference based on the definition of the dynamic liquid surface: Where: T T ,T O ——Well casing pressure of pumping unit, oil pressure, MPa; The dynamic load CH can be determined by the theoretical calculation formula of the suspension point load: B The relationship between stroke, stroke frequency and buoyancy coefficient is: The definition formula of reaction ratio is: Where: k——reaction ratio; The formula for calculating the reaction force ratio considering the pump barrel filling factor is: in: η=S p / S (Formula 13) Where: η- is the degree of pump filling; k'-reduced reaction force ratio under the degree of underfilling; S p -Effective stroke, m, is calculated by the effective stroke scanning interception method of the power diagram.

7. The algorithm for calculating the dynamic liquid level by the reaction force ratio method of the pumping well according to claim 1 is characterized in that: The dynamic liquid level formula obtained in step S104 is: Combined with the factor of the pump barrel being full, the reaction force ratio formula is replaced by the reaction force ratio formula to obtain the final converted dynamic liquid level formula:

8. The algorithm for calculating the dynamic liquid level by the reaction force ratio method of the pumping well according to claim 7 is characterized in that: The specific method of step S2, based on the established dynamic liquid level conversion algorithm model, obtaining the field measured data and the required static data in real time, and determining the converted dynamic liquid level data by calculation, includes: S201, obtaining the upward load of the suspension point, the downward load of the suspension point, the measured stroke, and the measured stroke frequency through the work diagram collected in real time by the digital load sensor; S202, obtaining wellhead oil pressure and casing pressure data in real time through a wellhead digital pressure gauge; S203, calculating the rod column buoyancy influence coefficient b and the well fluid specific gravity through the artificially recorded water content; S204, through the report, retrieve two static parameters of water content and pump hanging depth in real time; S205, for wells with different working conditions, determine the pump filling degree; considering the pump filling degree, calculate the effective stroke by the work diagram effective stroke scanning interception method, and calculate the conversion reaction force ratio; S206. After obtaining the measured data, static data and converted reaction force ratio required by the dynamic liquid level calculation algorithm through the above steps, the dynamic liquid level data is calculated through the final converted dynamic liquid level formula.

9. The algorithm for calculating the dynamic liquid level by the reaction force ratio method of the pumping well according to claim 1 is characterized in that: The S3 compares the above calculated dynamic liquid level data with the dynamic liquid level actually measured by the on-site acoustic wave method, and the error standard for evaluation is within ±50m.

10. The algorithm for calculating the dynamic liquid level by the reaction force ratio method of the pumping well according to claim 9 is characterized in that: The method S3 compares the above-calculated dynamic liquid level data with the dynamic liquid level actually measured by the on-site acoustic wave method, evaluates it according to a certain error standard, and verifies the accuracy of the dynamic liquid level conversion algorithm, including: The converted dynamic liquid level is compared with the dynamic liquid level actually measured by the on-site acoustic wave method, and verified in wells with different working conditions and evaluated according to the error standard within ±50m; the different working conditions wells include normal wells, gas-affected wells, insufficient liquid supply wells, and disconnection and leakage wells; Verify and determine under which working conditions the converted dynamic liquid level error can be controlled within the error standard; Through verification, it is found that the pump barrel is filled to a high degree in normal wells and wells with disconnection and leakage, and the converted dynamic liquid level error can be controlled within the error standard; Through verification, it is found that for wells affected by gas and insufficient liquid supply, the pump barrel is not filled to a low degree. The dynamic liquid level conversion algorithm formula when the pump barrel is not full is applied to determine whether the dynamic liquid level error of wells affected by gas and insufficient liquid supply can be controlled within the error standard.

Images