Method and device for determining working fluid level under different fluid supply working conditions

Abstract

The invention relates to the technical field of working fluid levels of oil pumping units, in particular to a method and device for determining the working fluid levels under different fluid supply working conditions. The method comprises the following steps: acquiring basic data of a target oil well, an indicator diagram under the working condition of insufficient liquid supply and an indicator diagram of a working fluid level to be determined; key points are identified on the indicator diagram under the working condition of insufficient liquid supply, and the friction load and the effective liquid column load of the target oil well are determined according to the load data corresponding to the key points; judging whether the target oil well is in an insufficient liquid supply working condition state or a sufficient liquid supply working condition state according to the to-be-determined working liquid level indicator diagram; determining the working fluid level depth of the target oil well according to the effective fluid column load and the basic data if the working condition is the insufficient fluid supply working condition, and determining the working fluid level depth of the target oil well according to the friction load and the basic data if the working condition is the sufficient fluid supply working condition. The invention aims to solve the problems that the comparison between a working fluid level value calculated based on an indicator diagram and a measured value is severely large and the accuracy is low because the frictional resistance cannot be accurately calculated.

Description

Technical Field

[0001] The invention relates to the technical field of dynamic fluid level in oil pumping, and in particular to a method and device for determining the dynamic fluid level under different fluid supply conditions. Background Art

[0002] The dynamic liquid level is the distance between the liquid level in the annular space of the tubing and casing and the wellhead during normal production. The dynamic liquid level of an oil well is an important indicator of the formation's fluid supply capacity and an important basis for determining a reasonable submergence and formulating a reasonable work system in an oil field. Dynamic liquid level measurement methods such as the echo method and the pressure gauge detection method have been used for a long time and the technology is relatively mature, but due to inconvenient construction or high equipment costs, they are not suitable for long-term automated management. With the continuous advancement of the digitalization process of oil fields, the calculation of the dynamic liquid level depth based on the indicator diagram has received widespread attention. However, since the indicator diagram is affected by friction forces such as the friction resistance between the sucker rod and the tubing in the wellbore, the friction resistance between the plunger and the pump barrel, and the friction resistance between the liquid column and the tubing, especially in the case of insufficient fluid supply, the friction resistance cannot be accurately calculated, resulting in a serious difference between the calculated dynamic liquid level value and the measured value, and the calculation accuracy is low, resulting in the on-site dynamic liquid level depth calculation algorithm based on the indicator diagram not being widely promoted and applied. Summary of the invention

[0003] The present invention proposes a method and device for determining the dynamic liquid level under different liquid supply conditions, so as to solve the problem that the dynamic liquid level value calculated based on the indicator diagram is seriously larger than the measured value and has low accuracy due to the inability to accurately calculate the friction resistance.

[0004] According to one aspect of the present invention, a method for determining a dynamic liquid level under different liquid supply conditions is provided, comprising:

[0005] Obtain the basic data of the target oil well, the dynamometer diagram under the condition of insufficient fluid supply, and the dynamometer diagram of the dynamic fluid level to be determined;

[0006] Identifying key points on the dynamometer diagram under the insufficient fluid supply condition, and determining the friction load and effective liquid column load of the target oil well according to the load data corresponding to the key points;

[0007] Judging whether the target oil well is in a state of insufficient liquid supply or sufficient liquid supply according to the dynamic liquid level indicator diagram to be determined;

[0008] If the working condition is insufficient liquid supply, the dynamic liquid level depth of the target oil well is determined based on the effective liquid column load and the basic data. If the working condition is sufficient liquid supply, the dynamic liquid level depth of the target oil well is determined based on the friction load and the basic data.

[0009] Preferably, the key points include: a floating valve closing point A, and / or a fixed valve opening point B, and / or a fixed valve closing point C, and / or a friction turning point C1, and / or a liquid impact point D1, and / or a floating valve opening point D.

[0010] Preferably, the method for determining the friction load of the target oil well according to the corresponding load data of the key points comprises:

[0011] Determine the load average F of all data points between the key points B and C BC ;

[0012] Determine the load average F of all data points between the key points C1 and D1 C1D1 ;

[0013] According to the F BC and F C1D1 , use formula (1) to determine the friction load F S ;

[0014]

[0015] Preferably, the method for determining the effective liquid column load of the target oil well according to the corresponding load data of the key point comprises:

[0016] Determine the load average F of all data points between the key points A and D AD ;

[0017] Determine the load average F of all data points between the key points C1 and D1 C1D1 ;

[0018] According to the F AD and F C1D1 , use formula (2) to determine the effective liquid column load F L ;

[0019] F L =F C1D1 -F AD (2).

[0020] Preferably, the basic data include: well fluid density, wellhead oil pressure, wellhead casing pressure and pump diameter of the target oil well.

[0021] Preferably, the method for determining the dynamic liquid level depth of the target oil well according to the effective liquid column load and the basic data comprises:

[0022] According to the basic data and the effective liquid column load, the dynamic liquid level depth of the target oil well under the condition of insufficient liquid supply is determined using formula (3);

[0023]

[0024] Where: H is the depth of the dynamic liquid surface, m; F L is the effective liquid column load, N; P t is the wellhead oil pressure, Pa; P c is the casing pressure at the wellhead, Pa; d is the pump diameter of the oil well pump, m; ρ L is the well fluid density, kg·m -3 ; g is the acceleration due to gravity, m / s 2 .

[0025] Preferably, the method for determining the dynamic liquid level depth of the target oil well according to the friction load and the basic data comprises:

[0026] According to the basic data, the load data corresponding to the key points and the effective liquid column load, the dynamic liquid level depth of the target oil well under the condition of sufficient liquid supply is determined by using formula (4);

[0027]

[0028] Where: H is the depth of the dynamic liquid surface, m; F BC is the load average of all data points between key points B and C, N; F AD is the load average of all data points between key points A and D, N; F S is the friction load, N; P t is the wellhead oil pressure, Pa; P c is the casing pressure at the wellhead, Pa; d is the pump diameter of the oil well pump, m; ρ L is the well fluid density, kg·m -3 ; g is the acceleration due to gravity, m / s 2 .

[0029] Preferably, the method of judging whether the target oil well is in a state of insufficient liquid supply or sufficient liquid supply according to the dynamic liquid level indicator diagram to be determined comprises:

[0030] Determine whether the filling degree of the oil pump of the target oil well is lower than a predetermined percentage according to the dynamic liquid level indicator diagram to be determined, if yes, it is in a state of insufficient liquid supply, otherwise, it is in a state of sufficient liquid supply;

[0031] The fullness of the oil pump is: the ratio of the displacement from key point A to D to the displacement from key point B to C on the dynamic liquid level indicator diagram to be determined.

[0032] According to one aspect of the present invention, a device for determining a dynamic liquid level under different liquid supply conditions is provided, comprising:

[0033] An acquisition unit, used to acquire basic data of a target oil well, a dynamometer diagram under a condition of insufficient liquid supply, and a dynamometer diagram of a dynamic liquid level to be determined;

[0034] A friction load and effective liquid column load determination unit, used to identify key points on the dynamometer diagram under the insufficient liquid supply condition, and determine the friction load and effective liquid column load of the target oil well according to the load data corresponding to the key points;

[0035] A dynamic liquid level depth determination unit, used for judging whether the target oil well is in a state of insufficient liquid supply or sufficient liquid supply according to the dynamic liquid level indicator diagram to be determined;

[0036] If the working condition is insufficient liquid supply, the dynamic liquid level depth of the target oil well is determined based on the effective liquid column load and the basic data. If the working condition is sufficient liquid supply, the dynamic liquid level depth of the target oil well is determined based on the friction load and the basic data.

[0037] The present invention has at least the following beneficial effects:

[0038] The present invention proposes a method and device for determining the dynamic liquid level under different liquid supply conditions, which effectively improves the calculation accuracy of the dynamic liquid level by determining the effective liquid column load and friction load through the indicator diagram under the condition of insufficient liquid supply. When the liquid supply is sufficient, the calculation accuracy of the dynamic liquid level under the condition of sufficient liquid supply can be further improved according to the friction resistance determined when the liquid supply is insufficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The accompanying drawings herein are incorporated into and constitute a part of the specification. These drawings illustrate embodiments consistent with the present invention and, together with the specification, are used to explain the technical solutions of the present invention.

[0040] Figure 1 A flow chart showing a method for determining a dynamic liquid level under different liquid supply conditions according to an embodiment of the present invention;

[0041] Figure 2 The key points on the dynamometer diagram according to the embodiment of the present invention and the friction load and the effective liquid column load are shown;

[0042] Figure 3 The dynamometer diagram under the condition of insufficient liquid supply according to an embodiment of the present invention is shown;

[0043] Figure 4 A downhole pump diagram according to an embodiment of the present invention is shown;

[0044] Figure 5 A dynamometer diagram under a sufficient liquid supply condition according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0045] Various exemplary embodiments, features and aspects of the present invention will be described in detail below with reference to the accompanying drawings. The same reference numerals in the accompanying drawings represent elements with the same or similar functions. Although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless otherwise specified.

[0046] The word “exemplary” is used exclusively herein to mean “serving as an example, example, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.

[0047] The term "and / or" herein is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the term "at least one" herein represents any combination of at least two of any one or more of a plurality of. For example, including at least one of A, B, and C can represent including any one or more elements selected from the set consisting of A, B, and C.

[0048] In addition, in order to better illustrate the present invention, numerous specific details are provided in the following specific embodiments. It should be understood by those skilled in the art that the present invention can be implemented without certain specific details. In some examples, methods, means, components and circuits well known to those skilled in the art are not described in detail in order to highlight the subject matter of the present invention.

[0049] Figure 1 A flow chart showing a method for determining a dynamic liquid level under different liquid supply conditions according to an embodiment of the present invention; Figure 2 The key points on the dynamometer diagram according to the embodiment of the present invention and the friction load and the effective liquid column load are shown; Figure 3 The dynamometer diagram under the condition of insufficient liquid supply according to an embodiment of the present invention is shown; Figure 4 A downhole pump diagram according to an embodiment of the present invention is shown; Figure 5 FIG. 2 shows a dynamometer diagram under a sufficient liquid supply condition according to an embodiment of the present invention. Figure 1-5As shown, a method for determining the dynamic liquid level under different fluid supply conditions includes: step S01: acquiring basic data of the target oil well, a dynamometer diagram under the condition of insufficient fluid supply, and a dynamometer diagram of the dynamic liquid level to be determined; step S02: identifying key points on the dynamometer diagram under the condition of insufficient fluid supply, and determining the friction load and the effective liquid column load of the target oil well according to the load data corresponding to the key points; step S03: judging whether the target oil well is in a state of insufficient fluid supply or a state of sufficient fluid supply according to the dynamometer diagram of the dynamic liquid level to be determined; if it is in a state of insufficient fluid supply, determining the dynamic liquid level depth of the target oil well according to the effective liquid column load and the basic data, and if it is in a state of sufficient fluid supply, determining the dynamic liquid level depth of the target oil well according to the friction load and the basic data.

[0050] The method for determining the dynamic liquid level under different liquid supply conditions provided by the embodiment of the present invention specifically includes the following steps:

[0051] Step S01: Obtain basic data of the target oil well, a dynamometer diagram under a condition of insufficient fluid supply, and a dynamometer diagram of a dynamic fluid level to be determined.

[0052] In the present invention, the basic data include: well fluid density, wellhead oil pressure, wellhead casing pressure and wellbore pump diameter.

[0053] In the embodiment of the present invention, the indicator diagram can be obtained by collecting data from a load sensor installed on the wellhead suspension rope and an angular displacement sensor on the walking beam of the pumping unit; the load sensor and the angular displacement sensor measure the load (suspension point load) and displacement (suspension point displacement) of the pumping well to draw a ground work diagram (indicator diagram); it is also possible to collect electrical parameter data at the input end of the pumping unit, establish a relationship between the electrical parameter and the suspension point load, and then invert the indicator diagram through the electrical parameter; it can also be a downhole pump power diagram calculated based on the suspension point indicator diagram (ground power diagram). Compared with the indicator diagram, the downhole pump power diagram has a smoother curve, which can reduce the error when calculating the average value of data points.

[0054] Step S02: identifying key points on the dynamometer diagram under the insufficient fluid supply condition, and determining the friction load and effective liquid column load of the target oil well according to the load data corresponding to the key points.

[0055] In the present invention, the key points include: the floating valve closing point A, and / or the fixed valve opening point B, and / or the fixed valve closing point C, and / or the friction turning point C1, and / or the liquid impact point D1, and / or the floating valve opening point D.

[0056] In the embodiment of the present invention, the positions of the key points on the dynamometer diagram and the schematic diagram of the calculated friction load and effective liquid column load are shown in FIG. Figure 2 As shown, the method for determining the key points on the indicator diagram can adopt the maximum curvature method or the outer envelope maximum curvature method.

[0057] In the present invention, the method for determining the friction load of the target oil well according to the corresponding load data of the key points includes: determining the load average value F of all data points between the key points B and C BC ; Determine the load average F of all data points between the key points C1 and D1 C1D1 According to the F BC and F C1D1 , use formula (1) to determine the friction load F S ;

[0058]

[0059] In the embodiment of the present invention, the friction load F of the oil well S is the average load F BC With the average load F C1D1 Half the load difference.

[0060] Among them, the calculation formula for the load average value of all data points between the fixed valve opening point B and the fixed valve closing point C is:

[0061] Where, j = 1, 2, 3, ..., x-2;

[0062] Where: F B is the suspension point load corresponding to the key point B on the dynamometer diagram, F C is the suspension point load corresponding to the key point C on the dynamometer diagram, F j is the suspension point load corresponding to the data point between key points B and C, and x is the number of data points between key points B and C (including key points B and C).

[0063] The calculation formula for the load average value of all data points between the friction turning point C1 and the liquid impact point D1 is:

[0064] Where, k = 1, 2, 3, ..., s-2;

[0065] Where: F C1 is the suspension point load corresponding to the key point C1 on the dynamometer diagram, F D1 is the suspension point load corresponding to the key point D1 on the dynamometer diagram, F k is the suspension point load corresponding to the data point between key points C1 and D1, and s is the number of data points between key points C1 and D1 (including key points C1 and D1).

[0066] In the present invention, the method for determining the effective liquid column load of the target oil well according to the corresponding load data of the key points includes: determining the load average value F of all data points between the key points A and D AD ; Determine the load average F of all data points between the key points C1 and D1 C1D1 According to the F AD and F C1D1 , use formula (2) to determine the effective liquid column load F L ;

[0067] F L =F C1D1 -F AD (2).

[0068] In the embodiment of the present invention, the effective liquid column load F of the oil well L is the average load F C1D1 With the average load F AD Load difference.

[0069] Among them, the calculation formula for the load average value of all data points between the traveling valve closing point A and the traveling valve opening point D is:

[0070] Where, i=1,2,3,......,m-2;

[0071] Where: F A is the suspension point load corresponding to the key point A on the dynamometer diagram, F D is the suspension point load corresponding to the key point D on the dynamometer diagram, F i is the suspension point load corresponding to the data point between key points A and D, and m is the number of data points between key points A and D (including key points A and D).

[0072] Step S03: judging whether the target oil well is in a state of insufficient fluid supply or a state of sufficient fluid supply according to the dynamic fluid level indicator diagram to be determined.

[0073] In the present invention, the method for judging whether the target oil well is in a state of insufficient fluid supply or a state of sufficient fluid supply based on the dynamic fluid level indicator diagram to be determined comprises: determining whether the degree of fullness of the oil pump of the target oil well at this time is lower than a predetermined percentage based on the dynamic fluid level indicator diagram to be determined; if so, it is in a state of insufficient fluid supply; otherwise, it is in a state of sufficient fluid supply; wherein the degree of fullness of the oil pump is the ratio of the displacement from key point A to D to the displacement from key point B to C on the dynamic fluid level indicator diagram to be determined.

[0074] In the embodiment of the present invention, the predetermined percentage is: 90%. If the ratio of the displacement corresponding to the floating valve closing point A to the floating valve opening point D to the displacement corresponding to the fixed valve opening point B to the fixed valve closing point C is less than 90%, it means that the liquid supply state corresponding to the indicator diagram is a liquid supply insufficient working condition state, and if the ratio is greater than or equal to 90%, it means that the liquid supply state corresponding to the indicator diagram is a liquid supply sufficient working condition state.

[0075] In the present invention, if the working condition is insufficient fluid supply, the dynamic fluid level depth of the target oil well is determined based on the effective liquid column load and the basic data; if the working condition is sufficient fluid supply, the dynamic fluid level depth of the target oil well is determined based on the friction load and the basic data.

[0076] In the present invention, the method for determining the dynamic liquid level depth of the target oil well according to the effective liquid column load and the basic data comprises: determining the dynamic liquid level depth of the target oil well under the insufficient liquid supply working condition according to the basic data and the effective liquid column load using formula (3);

[0077]

[0078] Where: H is the depth of the dynamic liquid surface, m; F L is the effective liquid column load, N; P t is the wellhead oil pressure, Pa; P c is the casing pressure at the wellhead, Pa; d is the pump diameter of the oil well pump, m; ρ L is the well fluid density, kg·m -3 ; g is the acceleration due to gravity, m / s 2 .

[0079] In the present invention, the method for determining the dynamic liquid level depth of the target oil well according to the friction load and the basic data comprises: determining the dynamic liquid level depth of the target oil well under the condition of sufficient liquid supply by using formula (4) according to the basic data, the load data corresponding to the key points and the effective liquid column load;

[0080]

[0081] Where: H is the depth of the dynamic liquid surface, m; F BC is the load average of all data points between key points B and C, N; F AD is the load average of all data points between key points A and D, N; F S is the friction load, N; P t is the wellhead oil pressure, Pa; P c is the casing pressure at the wellhead, Pa; d is the pump diameter of the oil well pump, m; ρ L is the well fluid density, kg·m -3 ; g is the acceleration due to gravity, m / s2 .

[0082] In the embodiment of the present invention, under the condition of insufficient fluid supply to the target oil well, several basic data of the target oil well, such as the well fluid density, wellhead oil pressure, wellhead casing pressure, pump diameter of the oil pump, and the effective liquid column load, are substituted into formula (3) for calculation to obtain the dynamic liquid level depth H corresponding to the dynamic liquid level indicator diagram to be determined under the condition of insufficient fluid supply to the target oil well.

[0083] Under the condition of sufficient fluid supply to the target oil well, the basic data of the target oil well, such as the well fluid density, wellhead oil pressure, wellhead casing pressure, pump diameter of the oil well, the load average value of all data points between key points B and C, the load average value of all data points between key points A and D, and the friction load are substituted into formula (4) for calculation to obtain the dynamic liquid level depth H corresponding to the dynamic liquid level indicator diagram to be determined under the condition of sufficient fluid supply to the target oil well.

[0084] Since the friction load cannot be determined when the fluid supply is sufficient, a more accurate dynamic fluid level depth calculation result can be obtained by substituting the friction load determined by the indicator diagram under insufficient fluid supply into the dynamic fluid level calculation formula under sufficient fluid supply.

[0085] In the embodiment of the present invention, the target oil well 81-slant P042 is taken as an example. The well is a beam pumping well. The basic data of the downhole rod and tube pump of the oil well are: the pump diameter d of the oil pump is 56 mm, the well fluid density ρ L 9200kg / m 3 , wellhead oil pressure P t 0.3MPa, wellhead casing pressure P c It is 0.43MPa.

[0086] Figure 3 The surface power diagram obtained under the condition of insufficient fluid supply is shown. The surface power diagram may be a surface power diagram obtained by using a load sensor and a displacement sensor, or a surface power diagram derived by using electrical parameter data.

[0087] Use the maximum curvature method or the outer envelope maximum curvature method to find the dynamometer diagram ( Figure 3 ) are found out, namely the floating valve closing point A, the fixed valve opening point B, the fixed valve closing point C, the friction turning point C1, the liquid impact point D1, and the floating valve opening point D.

[0088] The displacement and load data of the six key points are: A (0, 33.18), B (0.3, 62.18), C (3, 57.08), C1 (2.96, 47.94), D1 (1.95, 49.28), D (1.39, 26.62);

[0089] Based on the key points found, calculate the average load FBC , average load F C1D1 and the average load F AD Value. Average load F BC is the average load value of all data points between B and C, and F is calculated BC =56.5kN; average load F C1D1 is the average load value of all data points between C1 and D1, and F is calculated C1D1 =49.8kN; average load F AD is the average load value of all data points between A and D, and F is calculated AD =32.9kN; According to formula (1), the friction load F is calculated s =3.35kN, according to formula (2) calculate the effective liquid column load F L =16.9kN.

[0090] According to formula (3), the dynamic liquid level depth under the condition of insufficient oil well supply is calculated as:

[0091]

[0092] The actual dynamic liquid level of the target oil well test is 704m, and the dynamic liquid level error between it and the calculated 723m is only 2.69%.

[0093] In the embodiment of the present invention, the target well 81-slant P042 is taken as an example. The well is a beam pumping well. The basic data of the downhole rod and tube pump of the oil well are: the pump diameter d of the oil pump is 56 mm, the well fluid density ρ L 9200kg / m 3 , wellhead oil pressure P t 0.3MPa, wellhead casing pressure P c It is 0.43MPa.

[0094] Figure 4 A method for obtaining a surface power diagram under insufficient fluid supply conditions is provided. The surface power diagram can be obtained using a load sensor and a displacement sensor, or can be derived using electrical parameter data; the surface power diagram is converted into a downhole pump power diagram. Figure 4 The solid line curve at the top is the surface performance diagram, and the dotted line curve at the bottom is the curve after being converted into the downhole pump performance diagram.

[0095] Use the maximum curvature method or the outer envelope maximum curvature method to find 6 key points on the pump performance diagram, namely, the floating valve closing point A, the fixed valve opening point B, the fixed valve closing point C, the friction turning point C1, the liquid impact point D1, and the floating valve opening point D;

[0096] The displacement and load data of the six key points are: A (0.02, -1.01), B (0.25, 20.57), C (2.80, 20.63), C1 (2.77, 16.14), D1 (1.92, 14.86), D (1.4., -1.33);

[0097] Based on the key points found, calculate the average load F BC , average load F C1D1 and the average load F AD Value. Average load F BC is the average load value of all data points between B and C, and F is calculated BC =20.61kN; average load F C1D1 is the average load value of all data points between C1 and D1, and F is calculated C1D1 =15.99kN; average load F AD is the average load value of all data points between A and D, and F is calculated AD =-1.12kN; According to formula (1), the friction load F is calculated s = 2.31 kN, according to formula (2) the effective liquid column load F is calculated L =17.11kN.

[0098] According to formula (3), the dynamic liquid level depth under the condition of insufficient oil well supply is calculated as:

[0099]

[0100] The actual dynamic liquid level of the target oil well test is 704m, and the error between the dynamic liquid level and the calculated 732m is only 3.97%.

[0101] In the embodiment of the present invention, the target well 81-slant P042 is taken as an example. The well is a beam pumping well. The basic data of the downhole rod and tube pump of the oil well are: the pump diameter d of the oil pump is 56 mm, the well fluid density ρ L 9200kg / m 3 , wellhead oil pressure P t 0.3MPa, wellhead casing pressure P c It is 0.43MPa.

[0102] Figure 5 The surface work diagram of the oil well under the condition of sufficient fluid supply is given. The friction load F corresponding to the surface work diagram is s =3.35kN.

[0103] Use the maximum curvature method or the outer envelope maximum curvature method to find four key points on the pump performance diagram, namely, the floating valve closing point A, the fixed valve opening point B, the fixed valve closing point C, and the floating valve opening point D.

[0104] The displacement and load data of the four key points are: A (0.02, 36.99), B (0.26, 55.26), C (2.98, 52.07), and D (2.84, 34.72).

[0105] Based on the key points found, calculate the average load F BC and the average load F AD Value. Average load F BC is the average load value of all data points between B and C, and F is calculated BC =52.52kN; average load F AD is the average load value of all data points between A and D, and F is calculated AD =33.44kN.

[0106] According to the friction load F s , using formula (4) to calculate the dynamic liquid level depth under the condition of sufficient oil well supply:

[0107]

[0108] The actual dynamic liquid level of the target oil well test is 508m, and the dynamic liquid level error between it and the calculated 527m is only 3.74%.

[0109] It can be understood that the above-mentioned various method embodiments mentioned in the present invention can be combined with each other to form a combined embodiment without violating the principle logic. Due to space limitations, the present invention will not go into details.

[0110] The execution subject of the method for determining the dynamic liquid level under different liquid supply conditions may be a device for determining the dynamic liquid level under different liquid supply conditions. For example, the method for determining the dynamic liquid level under different liquid supply conditions may be executed by a terminal device or a server or other processing device, wherein the terminal device may be a user equipment (UE), a mobile device, a user terminal, a terminal, a cellular phone, a cordless phone, a personal digital assistant (PDA), a handheld device, a computing device, a vehicle-mounted device, a wearable device, etc. In some possible implementations, the method for determining the dynamic liquid level under different liquid supply conditions may be implemented by a processor calling computer-readable instructions stored in a memory.

[0111] Those skilled in the art will appreciate that, in the above method of specific implementation, the order in which the steps are written does not imply a strict execution order and does not constitute any limitation on the implementation process. The specific execution order of the steps should be determined by their functions and possible internal logic.

[0112] The present invention also provides a device for determining the dynamic liquid level under different fluid supply conditions, comprising: an acquisition unit, used to acquire basic data of the target oil well, a dynamometer diagram under the condition of insufficient fluid supply, and a dynamic liquid level dynamometer diagram to be determined; a friction load and effective liquid column load determination unit, used to identify key points on the dynamometer diagram under the condition of insufficient fluid supply, and determine the friction load and effective liquid column load of the target oil well according to the load data corresponding to the key points; a dynamic liquid level depth determination unit, used to judge whether the target oil well is in a state of insufficient fluid supply or a state of sufficient fluid supply according to the dynamic liquid level dynamometer diagram to be determined; if it is in a state of insufficient fluid supply, the dynamic liquid level depth of the target oil well is determined according to the effective liquid column load and the basic data, and if it is in a state of sufficient fluid supply, the dynamic liquid level depth of the target oil well is determined according to the friction load and the basic data.

[0113] In some embodiments, the functions or modules and units included in the device provided by the embodiment of the present invention can be used to execute the method described in the above method embodiment. Its specific implementation can refer to the description of the above method embodiment. For the sake of brevity, it will not be repeated here.

[0114] Compared with the traditional method, the method of the present invention improves the accuracy of the dynamic liquid level depth calculation result by 10 to 15 percentage points, and the accuracy of the dynamic liquid level calculation can reach more than 93%. It can effectively improve the accuracy of the dynamic liquid level calculation result under the condition of insufficient liquid supply, and solve the problem that the dynamic liquid level value calculated based on the indicator diagram is seriously larger than the measured value due to the inability to accurately calculate the friction resistance of the rod and pipe.

[0115] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or technical improvements in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A method for determining the dynamic liquid level under different liquid supply conditions, characterized in that: include: Obtain the basic data of the target oil well, the dynamometer diagram under the condition of insufficient fluid supply, and the dynamometer diagram of the dynamic fluid level to be determined; Identifying key points on the dynamometer diagram under the insufficient fluid supply condition, and determining the friction load and effective liquid column load of the target oil well according to the load data corresponding to the key points; Judging whether the target oil well is in a state of insufficient liquid supply or sufficient liquid supply according to the dynamic liquid level indicator diagram to be determined; If the working condition is insufficient liquid supply, the dynamic liquid level depth of the target oil well is determined based on the effective liquid column load and the basic data. If the working condition is sufficient liquid supply, the dynamic liquid level depth of the target oil well is determined based on the friction load and the basic data.

2. The method for determining the dynamic liquid level under different liquid supply conditions according to claim 1, characterized in that: The key points include: the floating valve closing point A, and / or the fixed valve opening point B, and / or the fixed valve closing point C, and / or the friction turning point C1, and / or the liquid impact point D1, and / or the floating valve opening point D.

3. The method for determining the dynamic liquid level under different liquid supply conditions according to claim 2, characterized in that: The method for determining the friction load of the target oil well according to the corresponding load data of the key points includes: Determine the load average F of all data points between the key points B and C BC ; Determine the load average F of all data points between the key points C1 and D1 C1D1 ; According to the F BC and F C1D1 , use formula (1) to determine the friction load F S ; 4. The method for determining the dynamic liquid level under different liquid supply conditions according to claim 2, characterized in that: The method for determining the effective liquid column load of the target oil well according to the corresponding load data of the key point comprises: Determine the load average F of all data points between the key points A and D AD ; Determine the load average F of all data points between the key points C1 and D1 C1D1 ; According to the F AD and F C1D1 , use formula (2) to determine the effective liquid column load F L ; F L =F C1D1 -F AD (2)。 5. The method for determining the dynamic liquid level under different liquid supply conditions according to claim 2, characterized in that: The basic data include: well fluid density, wellhead oil pressure, wellhead casing pressure and pump diameter of the target oil well.

6. The method for determining the dynamic liquid level under different liquid supply conditions according to claim 5, characterized in that: The method for determining the dynamic liquid level depth of the target oil well according to the effective liquid column load and the basic data comprises: According to the basic data and the effective liquid column load, the dynamic liquid level depth of the target oil well under the condition of insufficient liquid supply is determined using formula (3); Where: H is the depth of the dynamic liquid surface, m; F L is the effective liquid column load, N; P t is the wellhead oil pressure, Pa; P c is the casing pressure at the wellhead, Pa; d is the pump diameter of the oil well pump, m; ρ L is the well fluid density, kg·m -3 ; g is the acceleration due to gravity, m / s 2 .

7. The method for determining the dynamic liquid level under different liquid supply conditions according to claim 5, characterized in that: The method for determining the dynamic liquid level depth of the target oil well according to the friction load and the basic data includes: According to the basic data, the load data corresponding to the key points and the effective liquid column load, the dynamic liquid level depth of the target oil well under the condition of sufficient liquid supply is determined by using formula (4); Where: H is the depth of the dynamic liquid surface, m; F BC is the load average of all data points between key points B and C, N; F AD is the load average of all data points between key points A and D, N; F S is the friction load, N; P t is the wellhead oil pressure, Pa; P c is the casing pressure at the wellhead, Pa; d is the pump diameter of the oil well pump, m; ρ L is the well fluid density, kg·m -3 ; g is the acceleration due to gravity, m / s 2 .

8. The method for determining the dynamic liquid level under different liquid supply conditions according to any one of claims 2 to 7, characterized in that: The method for judging whether the target oil well is in a state of insufficient liquid supply or sufficient liquid supply according to the dynamic liquid level indicator diagram to be determined comprises: Determine whether the filling degree of the oil pump of the target oil well is lower than a predetermined percentage according to the dynamic liquid level indicator diagram to be determined, if yes, it is in a state of insufficient liquid supply, otherwise, it is in a state of sufficient liquid supply; The fullness of the oil pump is: the ratio of the displacement from key point A to D to the displacement from key point B to C on the dynamic liquid level indicator diagram to be determined.

9. A device for determining the dynamic liquid level under different liquid supply conditions, characterized in that: include: An acquisition unit, used to acquire basic data of the target oil well, a dynamometer diagram under insufficient fluid supply conditions, and a dynamometer diagram of a dynamic fluid level to be determined; A friction load and effective liquid column load determination unit, used to identify key points on the dynamometer diagram under the insufficient liquid supply condition, and determine the friction load and effective liquid column load of the target oil well according to the load data corresponding to the key points; A dynamic liquid level depth determination unit, used for judging whether the target oil well is in a state of insufficient liquid supply or sufficient liquid supply according to the dynamic liquid level indicator diagram to be determined; If the working condition is insufficient liquid supply, the dynamic liquid level depth of the target oil well is determined based on the effective liquid column load and the basic data. If the working condition is sufficient liquid supply, the dynamic liquid level depth of the target oil well is determined based on the friction load and the basic data.

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