Early warning method and device for oil and gas well overflow, electronic equipment and storage medium

Abstract

The invention provides an oil and gas well overflow early warning method and device, electronic equipment and a storage medium, and the corresponding method comprises the steps: arranging at least one high-frequency radar liquid level detector above a circulation tank of a target oil and gas well, so as to collect the liquid level height of the circulation tank in real time; generating an actual circulation volume change curve of the circulation tank according to the liquid level height; comparing the actual circulation volume change curve with a pre-generated theoretical circulation volume change curve of the circulation tank; comparing the actual casing pressure change curve with a pre-generated theoretical casing pressure change curve; and predicting the overflow risk of the target oil and gas well according to the comparison result of the actual circulation volume change curve and the theoretical circulation volume change curve and the comparison result of the actual casing pressure change curve and the theoretical casing pressure change curve. The liquid level of the drilling fluid circulation tank is measured in real time on the basis of the high-frequency radar which is accurate and easy to operate, different working condition characteristics of well drilling and completion are fused, and overflow leakage can be early warned accurately.

Description

Technical Field

[0001] The present application belongs to the field of oil and natural gas exploration technology, in particular to the field of risk control technology in the oil and gas well drilling process, and specifically to an early warning method and device for oil and gas well overflow. Background Art

[0002] Drilling investment accounts for a large proportion in oil and gas extraction. Safe and efficient drilling is of great significance to cost savings and construction safety. Well kicks and well leakage caused by complex geological conditions (including fractured carbonate reservoirs, high-temperature and high-pressure formations, deep-water narrow safety density window formations, etc.) and imperfect construction technology are important factors that seriously affect safe drilling, causing significant losses in manpower, financial resources, and material resources. Therefore, monitoring and early warning of well kicks and well leakage are of great significance to safe drilling construction and ensuring efficient drilling. In the existing technology, there are mainly the following methods for monitoring well kicks and well leakage:

[0003] (1) Flow meter monitoring method: This method uses a surface flow meter to monitor the changing trend of the drilling fluid outlet to determine well kicks and well losses. Since the surface drilling fluid outlet flow rate changes little when the initial well kick or well loss occurs, the flow meter outlet flow rate is used to determine the early warning delay, but the measurement accuracy is low. Another method is to compare the difference in the inflow and outflow volumes of the drilling fluid to determine well kicks or well losses. This method requires a relatively expensive Coriolis flow meter, which is expensive and difficult to modify the platform.

[0004] (2) The monitoring method based on the liquid level of the circulating tank is widely used. However, since the liquid level of the circulating tank is always in dynamic change and the cross-sectional area of ​​the circulating tank is large, it is difficult to accurately measure the volume change of the circulating tank, making it difficult to timely judge the occurrence of well kick and well leakage, and the early warning delay is relatively large;

[0005] (3) The monitoring method based on wellbore pressure: This method uses MWD data and wellbore pressure to determine the occurrence of well kick and well leakage through hydraulic calculation. However, this method is greatly affected by the complex downhole working conditions, interference from the measurement environment, and data transmission speed, and can only be applied under the condition of drilling fluid return.

[0006] (4) A monitoring method based on the gas components of drilling fluid. This method is based on the air-permeable but water-impermeable properties of a semipermeable membrane. The concentration of hydrocarbon gas in the drilling fluid is monitored to determine the occurrence of wellbore. However, this method is greatly affected by the permeability of the semipermeable membrane and cannot be accurately measured under high pressure.

[0007] In summary, most current methods for identifying bottomhole leaks rely on a single detection method. Methods based on flow meters, existing circulating tank liquid level monitoring, wellbore pressure, and gas composition monitoring all have limitations, resulting in delays or limited accuracy in early warning of complex situations like bottomhole leaks. Therefore, the industry urgently needs a method for accurately measuring leak volume in real time. Furthermore, the current early warning mechanism for well kicks and lost circulation is unclear, warning thresholds are not defined based on field operating conditions, and the division of labor for ground operations is unclear. Consequently, a timely and accurate leak warning method and system is urgently needed. Summary of the Invention

[0008] One objective of the present invention is to provide an early warning method for oil and gas well overflows. This method uses precise and easy-to-use high-frequency radar to measure the fluid level in the drilling fluid circulation tank in real time. It integrates the characteristics of various drilling and completion conditions (drilling, drilling tool movement, tripping, and displacement adjustment), supplemented by dynamic analysis of parameters such as wellhead standing pressure and casing pressure, to provide accurate early warning of overflow conditions.

[0009] Another object of the present invention is to provide an early warning device for oil and gas well overflows. Another object of the present invention is to provide an electronic device comprising a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of the above-mentioned early warning method for oil and gas well overflows are implemented. Another object of the present invention is to provide a readable medium storing the computer program, and when the processor executes the computer program, the steps of the above-mentioned early warning method for oil and gas well overflows are implemented.

[0010] In order to solve the technical problems in the background technology of this application, the present invention provides the following technical solutions:

[0011] In a first aspect, the present invention provides an early warning method for oil and gas well overflow, comprising:

[0012] At least one high-frequency radar liquid level detector is placed above a circulation tank of a target oil and gas well to collect the liquid level height of the circulation tank in real time;

[0013] generating an actual circulation volume change curve of the circulation tank according to the liquid level;

[0014] Comparing the actual circulation volume change curve with a pre-generated theoretical circulation volume change curve of the circulation tank;

[0015] Compare the actual casing pressure change curve with the pre-generated theoretical casing pressure change curve;

[0016] The overflow risk of the target oil and gas well is predicted based on a comparison result between the actual circulation volume change curve and the theoretical circulation volume change curve and a comparison result between the actual casing pressure change curve and the theoretical casing pressure change curve.

[0017] In some embodiments of the present invention, the step of placing at least one high-frequency radar liquid level detector above a circulation tank of a target oil and gas well to collect the liquid level of the circulation tank in real time includes:

[0018] Measuring the time difference and the difference frequency between the transmitted wave and the reflected wave by the high-frequency radar liquid level detector;

[0019] The liquid level height is calculated according to the time difference and the difference frequency.

[0020] In some embodiments of the present invention, the step of generating the theoretical cycle volume change curve includes:

[0021] Generate inlet and outlet flow rates based on the pump stroke count and the speed at which the string is lifted or lowered;

[0022] The theoretical cycle volume change curve is generated according to the inlet and outlet flow rates.

[0023] In some embodiments of the present invention, the step of generating the theoretical casing pressure variation curve includes:

[0024] Calculate theoretical casing pressure value based on vertical pressure and wellbore structure;

[0025] The theoretical casing pressure variation curve is generated according to the theoretical casing pressure value.

[0026] In some embodiments of the present invention, predicting the overflow risk of the target oil and gas well according to the comparison result of the actual circulation volume change curve and the theoretical circulation volume change curve and the comparison result of the actual casing pressure change curve and the theoretical casing pressure change curve includes:

[0027] When the difference between the actual circulation volume change curve and the theoretical circulation volume change curve is greater than a first preset threshold, and the difference between the actual casing pressure change curve and the theoretical casing pressure change curve is greater than a second preset threshold, performing pressure control operation on the target oil and gas well;

[0028] When the difference between the bottom hole pressure and the formation fracture pressure is greater than a third preset threshold, an overflow alarm of the target oil and gas well is issued.

[0029] In some embodiments of the present invention, an early warning method for oil and gas well overflow further includes:

[0030] The pool volume fluctuation data caused by drilling tool activity is calculated based on the drilling tool lifting speed or lowering speed, drilling tool assembly data, and wellbore data.

[0031] In some embodiments of the present invention, an early warning method for oil and gas well overflow further includes:

[0032] The actual circulation volume change curve is corrected according to the pool volume fluctuation data.

[0033] In a second aspect, the present invention provides an early warning device for oil and gas well overflow, the device comprising:

[0034] A liquid level detector setting module is used to set at least one high-frequency radar liquid level detector above the circulation tank of the target oil and gas well to collect the liquid level height of the circulation tank in real time;

[0035] An actual circulation curve generating module, configured to generate an actual circulation volume change curve of the circulation tank according to the liquid level;

[0036] a first curve comparison module, configured to compare the actual circulation volume change curve with a pre-generated theoretical circulation volume change curve of the circulation tank;

[0037] The second curve comparison module is used to compare the actual casing pressure change curve with the pre-generated theoretical casing pressure change curve;

[0038] The overflow risk prediction module is used to predict the overflow risk of the target oil and gas well based on the comparison results of the actual circulation volume change curve and the theoretical circulation volume change curve and the comparison results of the actual casing pressure change curve and the theoretical casing pressure change curve.

[0039] In some embodiments of the present invention, the liquid level detector setting module includes:

[0040] A time difference measuring unit, configured to measure the time difference and difference frequency between the transmitted wave and the reflected wave by means of the high-frequency radar liquid level detector;

[0041] A liquid level calculation unit is used to calculate the liquid level according to the time difference and the difference frequency.

[0042] In some embodiments of the present invention, an early warning device for oil and gas well overflow further includes:

[0043] A theoretical cycle curve generating module, configured to generate the theoretical cycle volume change curve;

[0044] The theoretical cycle curve generation module includes:

[0045] The inlet and outlet flow generation module is used to generate the inlet and outlet flow rates according to the pump stroke number and the speed of the pipe string lifting or lowering;

[0046] The theoretical circulation curve generating unit is used to generate the theoretical circulation volume change curve according to the inlet and outlet flow rates.

[0047] In some embodiments of the present invention, an early warning device for oil and gas well overflow further includes:

[0048] A theoretical casing pressure curve generating module, configured to generate the theoretical casing pressure variation curve;

[0049] The theoretical casing pressure curve generation module includes:

[0050] Theoretical casing pressure value calculation unit, used to calculate the theoretical casing pressure value according to the vertical pressure and wellbore structure;

[0051] The theoretical casing pressure curve generating unit is used to generate the theoretical casing pressure change curve according to the theoretical casing pressure value.

[0052] In some embodiments of the present invention, the overflow risk prediction module includes:

[0053] a pressure control operation unit, configured to perform a pressure control operation on the target oil and gas well when the difference between the actual circulation volume change curve and the theoretical circulation volume change curve is greater than a first preset threshold, and when the difference between the actual casing pressure change curve and the theoretical casing pressure change curve is greater than a second preset threshold;

[0054] The overflow alarm issuing unit is used to issue an overflow alarm for the target oil and gas well when the difference between the bottom hole pressure and the formation fracture pressure is greater than a third preset threshold.

[0055] In some embodiments of the present invention, an early warning device for oil and gas well overflow further includes:

[0056] The pool volume fluctuation calculation module is used to calculate the pool volume fluctuation data caused by drilling tool activities based on the drilling tool lifting speed or lowering speed, drilling tool assembly data, and wellbore data.

[0057] In some embodiments of the present invention, an early warning device for oil and gas well overflow further includes:

[0058] The actual circulation curve correction module is used to correct the actual circulation volume change curve according to the pool volume fluctuation data.

[0059] In a third aspect, the present invention provides a computer program product, comprising a computer program / instruction, which, when executed by a processor, implements the steps of an early warning method for oil and gas well overflow.

[0060] In a fourth aspect, the present invention provides an electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, steps of a method for early warning of oil and gas well overflow are implemented.

[0061] In a fifth aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of an early warning method for oil and gas well overflow.

[0062] From the above description, it can be seen that an embodiment of the present invention provides an early warning method and device for oil and gas well overflow. The corresponding early warning method for oil and gas well overflow includes: setting at least one high-frequency radar liquid level detector above the circulation tank of the target oil and gas well to collect the liquid level height of the circulation tank in real time; generating an actual circulation volume change curve of the circulation tank according to the liquid level height; then, comparing the actual circulation volume change curve with the pre-generated theoretical circulation volume change curve of the circulation tank; comparing the actual casing pressure change curve with the pre-generated theoretical casing pressure change curve; finally, predicting the overflow risk of the target oil and gas well based on the comparison results of the actual circulation volume change curve and the theoretical circulation volume change curve and the comparison results of the actual casing pressure change curve and the theoretical casing pressure change curve.

[0063] The corresponding early warning device for oil and gas well overflow includes: a liquid level detector setting module, which is used to set at least one high-frequency radar liquid level detector above the circulation tank of the target oil and gas well to collect the liquid level height of the circulation tank in real time; an actual circulation curve generation module, which is used to generate an actual circulation volume change curve of the circulation tank according to the liquid level; a first curve comparison module, which is used to compare the actual circulation volume change curve with the pre-generated theoretical circulation volume change curve of the circulation tank; a second curve comparison module, which is used to compare the actual casing pressure change curve with the pre-generated theoretical casing pressure change curve; an overflow risk prediction module, which is used to predict the overflow risk of the target oil and gas well based on the comparison results of the actual circulation volume change curve and the theoretical circulation volume change curve and the comparison results of the actual casing pressure change curve and the theoretical casing pressure change curve.

[0064] The present invention uses a precise and easy-to-operate high-frequency radar to measure the liquid level in the drilling fluid circulation tank in real time. It integrates the characteristics of different drilling and completion conditions (drilling, moving the drill tool up and down, tripping and drilling, and adjusting the displacement), and supplemented by dynamic analysis of parameters such as wellhead vertical pressure and casing pressure, to provide accurate early warning of leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0066] Figure 1 A schematic flow chart of an oil and gas well overflow early warning method according to an embodiment of the present invention;

[0067] Figure 2 This is a flow chart of step 100 of an oil and gas well overflow early warning method according to an embodiment of the present invention;

[0068] Figure 3 Another flow chart of an oil and gas well overflow early warning method according to an embodiment of the present invention;

[0069] Figure 4 This is a flow chart of step 600 of an oil and gas well overflow early warning method according to an embodiment of the present invention;

[0070] Figure 5 This is a third flow chart of an oil and gas well overflow early warning method according to an embodiment of the present invention;

[0071] Figure 6 This is a flow chart of step 700 of an oil and gas well overflow early warning method according to an embodiment of the present invention;

[0072] Figure 7 This is a flow chart of step 500 of an oil and gas well overflow early warning method according to an embodiment of the present invention;

[0073] Figure 8 It is a structural diagram of a multi-source data acquisition and ground control system in a specific embodiment of the present invention;

[0074] Figure 9 Schematic diagram of the principle of the intelligent early warning system for leakage in a specific embodiment of the present invention;

[0075] Figure 10 Schematic diagram of the flow of the intelligent leakage identification method in a specific embodiment of the present invention;

[0076] Figure 11 is a block diagram of an early warning device for oil and gas well overflow in an embodiment of the present invention;

[0077] Figure 12 Schematic diagram of the structure of an electronic device in an embodiment of the present invention.

[0078] Reference numerals:

[0079] 1: MWD, PWD and LWD; 2: Pressure and temperature sensors; 3: Ball valve; 4: Throttle valve; 5: Flow meter; 6: High-frequency radar; 7: Circulation tank; 8: Back pressure pump; 9: Driller's room. DETAILED DESCRIPTION

[0080] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0081] It will be understood by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0082] It should be noted that the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or are inherent to these processes, methods, products or devices. The embodiments in this application and the features described in the embodiments may be combined with each other unless there is a conflict. The present application will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0083] The acquisition, storage, use, and processing of data in the technical solution of this application comply with relevant laws and regulations.

[0084] It is understandable that the occurrence of complex downhole situations such as well kicks and well leakage threatens the safety of oil and gas drilling well control. In severe cases, it may cause accidents such as well collapse, stuck drill, and blowout, which seriously affect the progress of drilling, reduce economic efficiency, and may even cause casualties and property losses. Therefore, timely early warning of complex downhole situations can effectively avoid the occurrence of major accidents and ensure efficient, safe and economical drilling.

[0085] Example 1:

[0086] Based on the above reasons, the embodiment of the present invention provides a specific implementation method of an oil and gas well overflow early warning method, see Figure 1 , specifically including the following contents:

[0087] Step 100: placing at least one high-frequency radar liquid level detector above a circulation tank of a target oil and gas well to collect the liquid level of the circulation tank in real time;

[0088] Step 200: generating an actual circulation volume change curve of the circulation tank according to the liquid level;

[0089] Step 300: Compare the actual circulation volume change curve with the pre-generated theoretical circulation volume change curve of the circulation tank;

[0090] Step 400: Compare the actual casing pressure change curve with the pre-generated theoretical casing pressure change curve;

[0091] Step 500: predicting the overflow risk of the target oil and gas well based on a comparison result between the actual circulation volume change curve and the theoretical circulation volume change curve and a comparison result between the actual casing pressure change curve and the theoretical casing pressure change curve.

[0092] From the above description, it can be seen that an embodiment of the present invention provides an early warning method for oil and gas well overflow, including: setting at least one high-frequency radar liquid level detector above the circulation tank of the target oil and gas well to collect the liquid level height of the circulation tank in real time; generating an actual circulation volume change curve of the circulation tank according to the liquid level height; then, comparing the actual circulation volume change curve with the pre-generated theoretical circulation volume change curve of the circulation tank; comparing the actual casing pressure change curve with the pre-generated theoretical casing pressure change curve; finally, predicting the overflow risk of the target oil and gas well based on the comparison results of the actual circulation volume change curve and the theoretical circulation volume change curve and the comparison results of the actual casing pressure change curve and the theoretical casing pressure change curve.

[0093] The present invention measures the liquid level in the circulation tank through high-frequency radar waves, and can perform real-time liquid volume monitoring without contacting the mud. The detection accuracy is at the millimeter level, and the real-time monitoring of the liquid volume changes in the circulation tank can be performed more accurately.

[0094] Example 2:

[0095] For step 100, the high-frequency radar liquid level detector is a device that uses the principle of radar waves to measure the surface height of liquid or material. Its working principle is generally based on microwave radar technology, especially time domain reflectometry (TDR) or frequency modulated continuous wave (FMCW) technology. The following is the specific implementation process of step 100: The high-frequency radar liquid level detector transmits microwave signals to the liquid surface through its antenna. These microwave signals are reflected back after hitting the liquid surface. The antenna of the detector receives the reflected signal. The device measures the time difference between the transmitted signal and the received reflected signal, or measures the frequency difference between the reflected signal and the original signal in FMCW technology. Through the propagation time or frequency difference of the signal, the device can calculate the distance from the antenna to the liquid surface. Since the dimensions of the container are known, the device can convert the distance into the liquid level height.

[0096] Regarding step 200, the circulation tank (also known as a circulation tank or mud tank in the circulation system) is a storage and processing unit for drilling fluid (commonly referred to as mud). The main function of this system is to circulate, condition, and clean the drilling fluid during drilling operations to ensure that its performance meets the requirements of the drilling operation. The functions of the circulation tank include:

[0097] Storage: The circulation tank provides sufficient storage space for drilling fluid, ensuring that drilling operations can proceed continuously.

[0098] Mixing: The tank is equipped with an agitator that can mix water, mud powder and other chemicals to prepare drilling fluid suitable for different drilling conditions.

[0099] Circulation: Through the action of the circulation pump, the drilling fluid is pumped from the circulation tank to the drill pipe and drill bit, and then flows back to the circulation tank to form a closed circulation system.

[0100] Cleaning: The circulation tank is often equipped with a desander and a desilter to remove solid particles in the drilling fluid, such as cuttings, to keep the drilling fluid clean and have stable rheological properties.

[0101] Adjustment: The density, viscosity and other properties of the drilling fluid can be adjusted in the circulation tank to adapt to different formation conditions and drilling requirements.

[0102] Preferably, the components of the circulation tank include:

[0103] Mud tank: mainly used to store and process drilling fluid.

[0104] Mixing equipment: keep the drilling fluid uniform and stable.

[0105] Pump equipment: including drilling fluid circulation pumps and delivery pumps.

[0106] Solids control equipment: used to remove solid impurities in mud, such as vibrating screens, desanders, desilters and centrifugal separators.

[0107] Measuring and control equipment: monitors the properties of the slurry and makes necessary adjustments.

[0108] Specifically, the drilling fluid circulation system described in this application operates as follows: drilling fluid is pumped from the circulation tank to the drilling pump. The drilling pump pumps the drilling fluid at high pressure to the drill pipe and drill bit. The drilling fluid aids in rock fragmentation at the drill bit and returns the cuttings to the surface. The returned drilling fluid is processed by solids control equipment to remove rock cuttings and solid particles. The cleaned drilling fluid then flows back to the circulation tank for recirculation.

[0109] In step 400, casing pressure is a term generally used in wellbore pressure management. It describes the pressure difference between the casing (a type of steel pipe) and the surrounding environment (such as the formation or other casing). Casing pressure can be positive or negative, and different management measures and engineering implications may apply depending on the specific situation.

[0110] When the pressure in the casing inside a well is higher than the pressure of the external environment, it is called positive casing pressure. Positive casing pressure is generally to be avoided because it can cause well control problems, such as:

[0111] Blowout: If the pressure in the well is too high, it may cause formation fluids (such as oil, gas, and water) to flow into the wellbore uncontrolled, thereby causing a blowout.

[0112] Tube rupture: If the well pressure exceeds the pressure-bearing capacity of the casing and casing joints, it may cause casing rupture.

[0113] Negative casing pressure refers to the pressure in the casing of a well being lower than the surrounding pressure. Negative casing pressure may cause the following problems:

[0114] Formation fluid invasion: Negative pressure differential may cause formation fluid (water or oil) to invade the wellbore, contaminating the drilling fluid or damaging the oil and gas formation.

[0115] Casing collapse: Prolonged negative pressure differentials may cause casing collapse, especially when the casing is not structurally strong enough to withstand the external pressure.

[0116] Casing pressure can be adjusted by adjusting the density of the circulating mud (drilling fluid) to manage static and dynamic pressures within the well. Using wellhead blowout preventers and other well control equipment, such as blowout preventers and shut-off valves, to control wellbore pressure. Regularly pressure testing the casing to detect any possible casing pressure anomalies.

[0117] In some embodiments of the present invention, see Figure 2 , step 100 includes:

[0118] Step 101: measuring the time difference and the difference frequency between the transmitted wave and the reflected wave by the high-frequency radar liquid level detector;

[0119] Step 102: Calculate the liquid level according to the time difference and the difference frequency.

[0120] Specifically, in step 101 and step 102, a high-frequency radar liquid level detector is suspended above the circulation tank to perform contactless real-time measurement of the liquid level. The distance between the radar and the liquid surface is calculated by measuring the time difference and frequency difference between the transmitted wave and the reflected wave. The average liquid level and liquid volume of the circulation tank can be obtained by conversion.

[0121] In addition, given the large fluctuations in the liquid level in the circulation tank, multiple high-frequency radars can be used in actual applications to fully cover the liquid surface, achieving a comprehensive projection of the liquid level in the circulation tank. The accurate average height can be obtained through data processing, and the liquid volume in the circulation tank can be calculated in reverse. Due to its high-frequency characteristics, the distance from the radar to the liquid surface can be monitored in real time, and the changes in the liquid volume in the circulation tank can also be monitored in real time.

[0122] In some embodiments of the present invention, see Figure 3 , an early warning method for oil and gas well overflow also includes:

[0123] Step 600: Generate the theoretical cycle volume change curve. Figure 4 , step 600 includes:

[0124] Step 601: Generate inlet and outlet flow rates based on the pump stroke count and the speed of raising or lowering the pipe string;

[0125] Step 602: Generate the theoretical cycle volume change curve according to the inlet and outlet flow rates.

[0126] Specifically, the inlet and outlet flow rates are analyzed according to the pump stroke count and the pipe string lifting (or lowering) speed to obtain a theoretical circulation tank volume change curve.

[0127] In some embodiments of the present invention, see Figure 5 , an early warning method for oil and gas well overflow also includes:

[0128] Step 700: generating the theoretical casing pressure variation curve;

[0129] Next, see Figure 6 , step 700 includes:

[0130] Step 701: Calculate theoretical casing pressure value based on vertical pressure and wellbore structure;

[0131] Step 702: Generate the theoretical casing pressure variation curve according to the theoretical casing pressure value.

[0132] In steps 701 and 702, hydraulics are used to calculate the theoretical casing pressure based on the vertical pressure, wellbore structure, and other factors. Specifically, the theoretical casing pressure refers to the pressure within the annulus (i.e., the annular space between the drill pipe and the wellbore wall) in the absence of a kick or blowout. Specifically, the theoretical casing pressure is calculated based on the wellbore geometry, mud properties, and bottomhole pressure.

[0133] To calculate the theoretical casing pressure, the following information is required:

[0134] Mud density (ρ): expressed in pounds per gallon (ppg) or grams per cubic centimeter (g / cm 3 )express.

[0135] Stand pressure (Hs): also known as hydrostatic pressure, is the pressure caused by the stationary mud column in the well, which depends on the density of the mud and the depth of the well.

[0136] Wellbore structure: wellbore diameter, well depth, wellbore trajectory, etc.

[0137] Mud flow rate and flow pattern: affect the calculation of friction resistance (friction pressure drop).

[0138] The calculation formula of the theoretical casing pressure is as follows:

[0139] P annulus = (ρ × Hs) + P friction

[0140] in:

[0141] (P{annulus}) is the annulus pressure (theoretical casing pressure value),

[0142] (ρ) is the mud density,

[0143] (Hs) is the vertical pressure height from the wellhead to the top of the mud column,

[0144] (P{friction}) is the frictional pressure drop due to the flow of mud through the annulus.

[0145] The friction pressure drop needs to be calculated through a hydraulic model that takes into account factors such as mud flow rate, viscosity, and wellbore diameter.

[0146] In some embodiments of the present invention, see Figure 7 , step 500 includes:

[0147] Step 501: When the difference between the actual circulation volume change curve and the theoretical circulation volume change curve is greater than a first preset threshold, and the difference between the actual casing pressure change curve and the theoretical casing pressure change curve is greater than a second preset threshold, performing pressure control operation on the target oil and gas well;

[0148] Step 502: When the difference between the bottom hole pressure and the formation fracture pressure is greater than a third preset threshold, an overflow alarm of the target oil and gas well is issued.

[0149] In step 501 and step 502, firstly, the ground casing pressure threshold is calculated according to the actual operating conditions and the formation pressure system, and the circulating tank liquid volume change threshold (second preset threshold) is designed. By comparing and analyzing the collected circulating tank fluid volume changes and casing pressure data with theoretical values, if the actual values ​​are consistent with the theoretical values, there is no bottomhole overflow, and normal operations are being carried out with real-time monitoring. If both actual values ​​are greater than the theoretical values, it indicates that formation fluid has entered the wellbore, causing overflow. If both differences are less than a threshold, pressure control operations are performed, bottomhole pressure is calculated, and bottomhole balance or slightly underbalance is maintained within a safe range below the formation fracture pressure. If the difference is greater than a threshold (a first preset threshold), operations need to be stopped and the operation plan re-planned. If both actual values ​​are less than the theoretical values, it indicates that mud has entered the formation, causing leakage. If the difference is less than the threshold, pressure control operations are performed, using a backpressure pump to replenish fluid, and balance or slightly underbalance is maintained within a safe range below the formation collapse pressure. If the difference is greater than the threshold, operations need to be stopped and the operation plan re-planned. If one actual value is greater than the theoretical value and the other is less than the theoretical value, it is determined that overflow and leakage may coexist, or other complex situations may occur, and the expert system needs to make decisions.

[0150] In some embodiments of the present invention, an early warning method for oil and gas well overflow further includes:

[0151] The pool volume fluctuation data caused by drilling tool activity is calculated based on the drilling tool lifting speed or lowering speed, drilling tool assembly data, and wellbore data.

[0152] In some embodiments of the present invention, an early warning method for oil and gas well overflow further includes:

[0153] The actual circulation volume change curve is corrected according to the pool volume fluctuation data.

[0154] Specifically, considering the displacement flow fluctuations caused by movable drilling tools, tripping, and inlet displacement changes:

[0155] (1) If the drill tool is raised (lowered) during the circulation process, the pool volume fluctuation caused by the drill tool activity needs to be calculated based on the raising (lowering) speed, drill tool assembly data, wellbore data, etc.

[0156] (2) During the drilling process, it is necessary to accurately calculate the inlet and outlet volume parameters that change with time based on the real-time collected drilling speed data and pump cycle data, so as to eliminate the fluctuation of the total pool volume caused by any normal operation.

[0157] As can be seen from the above description, the embodiments of the present invention provide an early warning method for oil and gas well overflows. First, a method is proposed for dynamically measuring the circulating tank liquid level using high-frequency radar to accurately and real-timely reflect changes in the circulating tank liquid volume. Multi-source real-time data acquisition and processing considers all drilling and completion conditions (drilling, drilling tools, tripping, displacement adjustment, etc.). It integrates parameters such as circulating tank liquid volume changes, ground casing pressure, vertical pressure, actual drilling parameters, tripping speed, wellbore dimensions, and wellbore structure for analysis. This intelligently identifies bottomhole overflows under different operating conditions, eliminating misjudgments of bottomhole overflows due to changes in pressure and circulating tank liquid volume caused by actual operating conditions. Furthermore, it proposes reasonable design of circulating tank liquid volume change thresholds and casing pressure thresholds under different drilling and completion conditions, sets a range for controllable pressure operations, reduces well shut-in time, and ensures a safe and efficient drilling and completion process. The responsible personnel for ground operations are divided, and the operating scope of the driller and pressure control engineer is clearly defined, making ground operations more rational.

[0158] Example 3:

[0159] To further illustrate the solution, in a specific embodiment, the present invention also provides a specific embodiment of an early warning method for oil and gas well overflow, which specifically includes the following contents.

[0160] First, the specific embodiment of the present invention also provides a multi-source data acquisition and ground control system, see Figure 8 , connect the ground equipment, the automatic throttle manifold and the pressure control device are connected to the blowout preventer, the flow meter and pressure sensor are connected to the data acquisition system, the driller's room and the data acquisition system are communicated with each other in real time, and MWD, PWD, LWD and other data are shared with the data acquisition system in real time. The collected data include ground inlet and outlet flow, vertical pressure, casing pressure, lifting (lowering) speed, drill tool assembly data, wellbore data, well depth structure, drilling pump, injection pump, top drive, drawworks and other working parameters. All data are transmitted to the data intelligent processing module together, and finally handed over to the control module for overflow warning and decision-making under the full drilling and completion conditions.

[0161] Based on the above-mentioned multi-source data acquisition and ground control system, the present invention also provides a specific implementation of an early warning method for oil and gas well overflow, including the following contents:

[0162] The intelligent early warning processing logic for leakage in the control module includes: calculating the surface flow and pressure changes according to the drilling and completion conditions (drilling, moving the drill bit up and down, tripping and lowering the drill bit, adjusting the displacement, etc.). On the one hand, the inlet and outlet flows are analyzed according to the pump stroke count and the speed of the pipe string lifting (or lowering) to obtain the theoretical circulation tank volume change curve. The volume change of the circulation tank is measured by high-frequency radar to obtain the actual volume change curve, which is compared with the theoretical volume change curve; on the other hand, considering the change in bottom hole pressure caused by actual working conditions, hydraulics is used to calculate the theoretical casing pressure value based on the vertical pressure, wellbore structure, etc., to obtain the theoretical casing pressure change curve under working conditions, and compare the actual casing pressure change curve with the theoretical curve. By analyzing the volume change of the circulating tank liquid and the casing pressure change, whether overflow or leakage occurs at the bottom of the well, the pressure control operation is automatically carried out according to the degree of overflow or handed over to the driller's room engineer for well control.

[0163] See also Figure 9 The method for classifying leakage severity based on bottomhole overflow includes collecting liquid level data from the circulation tank, surface downhole pressure data, and real-time drilling engineering parameters to determine whether leakage has occurred. This embodiment analyzes the drilling process and the tripping process.

[0164] During drilling: If there is no overflow, the ground casing pressure is analyzed to see if it exceeds 420psi. If it is lower than this value, drilling continues and the circulating tank liquid level and casing pressure are monitored in real time. If the ground casing pressure is higher than 420psi, an alarm is triggered, drilling is stopped, wellhead safety is ensured, and a new drilling plan is formulated. If overflow occurs and the overflow volume is greater than 5bbls, an alarm is immediately triggered, and a command is sent to the driller's room for well killing, and pressure-controlled assisted well killing is initiated. If the overflow volume is less than 5bbls and the ground casing pressure is greater than 420psi, an alarm is immediately triggered, and a command is sent to the driller's room for well killing, and pressure-controlled assisted well killing is initiated. If the overflow volume is less than 5bbls and the ground casing pressure is lower than 420psi, the pressure-controlled operation procedure is initiated, and balancing operations or slightly underbalancing are performed within the safe range of bottomhole pressure below the fracture pressure without stopping drilling.

[0165] In the stop drilling state, when drilling, observe whether the actual overflow volume is 0. If it is 0, there is no overflow. Determine whether the ground casing pressure exceeds 480psi. If it exceeds, alarm, stop the operation, and re-formulate the operation plan; if the ground casing pressure is lower than 480psi, operate normally and monitor the changes in the liquid level of the circulation tank and the ground casing pressure in real time. If overflow occurs and the overflow volume is greater than 5bbls, stop the operation, send a well pressure instruction to the driller's room, and control the pressure to assist in well pressure. If the overflow volume is less than 5bbls, but the ground casing pressure is higher than 480psi, alarm, stop the operation, and re-formulate the operation plan; if the overflow volume is less than 5bbls, and the ground casing pressure is not higher than 480psi, perform pressure control operations, and maintain balance or slightly underbalanced operations within the safe range where the bottom hole pressure is lower than the fracture pressure. It should be noted that the casing pressure threshold of this embodiment needs to be hydraulically calculated according to the actual operating conditions and the formation pressure system. It is not a fixed value, and the casing pressure needs to meet the following requirements:

[0166] P a +P ma +P fa <P f (1)

[0167] Where P a : casing pressure, MPa; P ma : annular liquid column pressure, MPa; P fa : Annular friction, MPa; p f : Formation fracture pressure.

[0168] It should be noted that the overflow threshold in this embodiment is reasonably designed according to working conditions.

[0169] The intelligent leakage identification method is described using the drilling process as an example. Figure 10 As shown in the figure, first calculate the theoretical value of the change in surface circulating tank liquid volume and the surface casing pressure caused by the pumping pressure or surge pressure during actual operation based on the tripping speed, drill pipe and environmental control size. The pumping pressure and surge pressure are calculated as follows:

[0170] Under laminar flow conditions:

[0171]

[0172] Under turbulent flow conditions:

[0173]

[0174] Where: P sw : pumping pressure or agitation pressure, MPa; v: annular flow velocity, cm / s; D h : borehole diameter, cm; D p: pipe outer diameter, cm; n: fluidity index, dimensionless; K: consistency coefficient; L: pipe length, cm; ρ: drilling fluid density, g / cm 3 ; f: friction coefficient.

[0175] The calculation method for the actual change in the circulating tank liquid volume during the tripping process is as follows:

[0176]

[0177] Where: V1: theoretical liquid volume change rate, cm 3 / s;D o : drill string outer diameter, cm; D i : Inner diameter of drill string, cm; V: Speed ​​of raising or lowering drill string, cm / s.

[0178] A specific embodiment of the present invention provides an early warning method and system for oil and gas well overflows. The system includes a multi-source real-time data acquisition system. The collected data contains operating parameters of the drilling pump, injection pump, top drive, drawworks, etc. Based on the above operating parameters and basic wellbore information, the working conditions of the entire drilling and completion process are accurately judged. Based on the accurate identification of the working conditions, the changes in the circulation pool volume and the inlet and outlet flow rates throughout the drilling and completion process are judged, eliminating all factors that may affect the accurate judgment of overflows, thereby improving the accuracy of overflow judgment.

[0179] In addition, the present invention is based on the real-time monitoring data of flow rate and circulation tank volume, and simultaneously performs time derivative analysis on them, and integrates the time derivative analysis of wellhead vertical pressure and casing pressure, and combines the intelligent automatic identification of different working conditions to eliminate the changes in flow rate, circulation tank volume, pressure and pressure derivative caused by normal working conditions, and conducts comprehensive early warning for leakage. According to the actual drilling working conditions and drilling parameters, hydraulic calculations are performed to obtain theoretical liquid volume changes and pressure changes, and the actual liquid volume changes and casing pressure changes are compared and analyzed with the theoretical values, and then it is determined whether the flow rate change or casing pressure change is caused by bottom hole leakage, avoiding the misjudgment of well kick or well leakage based solely on casing pressure or liquid volume changes. When a leakage is found, it is automatically processed according to the control capability of the on-site equipment. When it exceeds the automatic processing capability of the ground equipment, a warning is given in time, and the relevant person in charge is handed over to carry out well control processing according to the actual working conditions.

[0180] The intelligent leakage warning system proposed in the present invention has learning skills. When the measurement accuracy of the bottom hole equipment is high enough, the bottom hole pressure is transmitted in real time. A large amount of data is collected through the time and accuracy of the bottom hole pressure, ground casing pressure, and liquid volume changes when a leakage occurs, and a large number of response time differences from bottom hole leakage to the ground under different working conditions are obtained. When the bottom hole pressure can be accurately measured, the actual ground control time is given when abnormal bottom hole pressure is detected, which can effectively avoid the occurrence of serious situations.

[0181] In summary, the intelligent early warning method and system for leakage proposed in the present invention includes a complete set of ground real-time monitoring and control systems. The system can transmit MWD, PWD, and LWD data with the driller's room, and monitor the ground casing pressure and inlet and outlet flow at the same time. After processing the data, it gives corresponding instructions and performs automatic pressure control. When the automatic pressure control range is exceeded, an alarm will be issued and a well control instruction will be issued to the driller's room.

[0182] Example 4:

[0183] Based on the same inventive concept, the embodiments of the present application also provide an early warning device for oil and gas well overflow, which can be used to implement the method described in the above embodiments, such as the following embodiments. Since the principle of solving the problem by the early warning device for oil and gas well overflow is similar to that of the early warning method for oil and gas well overflow, the implementation of the early warning device for oil and gas well overflow can refer to the implementation of the early warning method for oil and gas well overflow, and the repeated parts will not be repeated. As used below, the term "unit" or "module" can be a combination of software and / or hardware that implements a predetermined function. Although the system described in the following embodiments is preferably implemented in software, implementation in hardware, or a combination of software and hardware, is also possible and conceivable.

[0184] The embodiment of the present invention provides a specific implementation of an oil and gas well overflow early warning device that can realize an oil and gas well overflow early warning method, see Figure 11 , an early warning device for oil and gas well overflow comprises:

[0185] A liquid level detector setting module 10 is used to set at least one high-frequency radar liquid level detector above the circulation tank of the target oil and gas well to collect the liquid level height of the circulation tank in real time;

[0186] An actual circulation curve generating module 20 is used to generate an actual circulation volume change curve of the circulation tank according to the liquid level;

[0187] a first curve comparison module 30 for comparing the actual circulation volume change curve with a pre-generated theoretical circulation volume change curve of the circulation tank;

[0188] A second curve comparison module 40 is used to compare the actual casing pressure change curve with the pre-generated theoretical casing pressure change curve;

[0189] The overflow risk prediction module 50 is used to predict the overflow risk of the target oil and gas well according to the comparison result of the actual circulation volume change curve and the theoretical circulation volume change curve and the comparison result of the actual casing pressure change curve and the theoretical casing pressure change curve.

[0190] In some embodiments of the present invention, the liquid level detector setting module includes:

[0191] A time difference measuring unit, configured to measure the time difference and difference frequency between the transmitted wave and the reflected wave by means of the high-frequency radar liquid level detector;

[0192] A liquid level calculation unit is used to calculate the liquid level according to the time difference and the difference frequency.

[0193] In some embodiments of the present invention, an early warning device for oil and gas well overflow further includes:

[0194] A theoretical cycle curve generating module, configured to generate the theoretical cycle volume change curve;

[0195] The theoretical cycle curve generation module includes:

[0196] The inlet and outlet flow generation module is used to generate the inlet and outlet flow rates according to the pump stroke number and the speed of the pipe string lifting or lowering;

[0197] The theoretical circulation curve generating unit is used to generate the theoretical circulation volume change curve according to the inlet and outlet flow rates.

[0198] In some embodiments of the present invention, an early warning device for oil and gas well overflow further includes:

[0199] A theoretical casing pressure curve generating module, configured to generate the theoretical casing pressure variation curve;

[0200] The theoretical casing pressure curve generation module includes:

[0201] Theoretical casing pressure value calculation unit, used to calculate the theoretical casing pressure value according to the vertical pressure and wellbore structure;

[0202] The theoretical casing pressure curve generating unit is used to generate the theoretical casing pressure change curve according to the theoretical casing pressure value.

[0203] In some embodiments of the present invention, the overflow risk prediction module includes:

[0204] a pressure control operation unit, configured to perform a pressure control operation on the target oil and gas well when the difference between the actual circulation volume change curve and the theoretical circulation volume change curve is greater than a first preset threshold, and when the difference between the actual casing pressure change curve and the theoretical casing pressure change curve is greater than a second preset threshold;

[0205] The overflow alarm issuing unit is used to issue an overflow alarm for the target oil and gas well when the difference between the bottom hole pressure and the formation fracture pressure is greater than a third preset threshold.

[0206] In some embodiments of the present invention, an early warning device for oil and gas well overflow further includes:

[0207] The pool volume fluctuation calculation module is used to calculate the pool volume fluctuation data caused by drilling tool activities based on the drilling tool lifting speed or lowering speed, drilling tool assembly data, and wellbore data.

[0208] In some embodiments of the present invention, an early warning device for oil and gas well overflow further includes:

[0209] The actual circulation curve correction module is used to correct the actual circulation volume change curve according to the pool volume fluctuation data.

[0210] From the above description, it can be seen that an embodiment of the present invention provides an early warning device for oil and gas well overflow, including: a liquid level detector setting module, used to set at least one high-frequency radar liquid level detector above the circulation tank of the target oil and gas well to collect the liquid level height of the circulation tank in real time; an actual circulation curve generation module, used to generate an actual circulation volume change curve of the circulation tank according to the liquid level; a first curve comparison module, used to compare the actual circulation volume change curve with the pre-generated theoretical circulation volume change curve of the circulation tank; a second curve comparison module, used to compare the actual casing pressure change curve with the pre-generated theoretical casing pressure change curve; an overflow risk prediction module, used to predict the overflow risk of the target oil and gas well based on the comparison results of the actual circulation volume change curve and the theoretical circulation volume change curve and the comparison results of the actual casing pressure change curve and the theoretical casing pressure change curve.

[0211] The present invention uses a precise and easy-to-operate high-frequency radar to measure the liquid level in the drilling fluid circulation tank in real time. It integrates the characteristics of different drilling and completion conditions (drilling, moving the drill tool up and down, tripping, and adjusting the displacement), supplemented by dynamic analysis of parameters such as wellhead standing pressure and casing pressure, to provide accurate early warning of leakage.

[0212] Embodiment 5:

[0213] The embodiment of the present application also provides a specific implementation of an electronic device that can implement all steps of the oil and gas well overflow early warning method in the above embodiment, see Figure 12 , electronic equipment specifically includes the following:

[0214] Processor 1201, memory 1202, communications interface 1203, and bus 1204;

[0215] The processor 1201, the memory 1202, and the communication interface 1203 communicate with each other via the bus 1204; the communication interface 1203 is used to implement information transmission between the server device and the client device and other related devices;

[0216] The processor 1201 is configured to call the computer program in the memory 1202. When the processor executes the computer program, all steps of the oil and gas well overflow early warning method in the above embodiment are implemented. For example, when the processor executes the computer program, the following steps are implemented:

[0217] At least one high-frequency radar liquid level detector is placed above a circulation tank of a target oil and gas well to collect the liquid level height of the circulation tank in real time;

[0218] generating an actual circulation volume change curve of the circulation tank according to the liquid level;

[0219] comparing the actual circulation volume change curve with a pre-generated theoretical circulation volume change curve of the circulation tank;

[0220] Compare the actual casing pressure change curve with the pre-generated theoretical casing pressure change curve;

[0221] The overflow risk of the target oil and gas well is predicted based on a comparison result between the actual circulation volume change curve and the theoretical circulation volume change curve and a comparison result between the actual casing pressure change curve and the theoretical casing pressure change curve.

[0222] In some embodiments of the present invention, the step of placing at least one high-frequency radar liquid level detector above a circulation tank of a target oil and gas well to collect the liquid level of the circulation tank in real time includes:

[0223] Measuring the time difference and the difference frequency between the transmitted wave and the reflected wave by the high-frequency radar liquid level detector;

[0224] The liquid level height is calculated according to the time difference and the difference frequency.

[0225] In some embodiments of the present invention, the step of generating the theoretical cycle volume change curve includes:

[0226] Generate inlet and outlet flow rates based on the pump stroke count and the speed at which the string is lifted or lowered;

[0227] The theoretical cycle volume change curve is generated according to the inlet and outlet flow rates.

[0228] In some embodiments of the present invention, the step of generating the theoretical casing pressure variation curve includes:

[0229] Calculate theoretical casing pressure value based on vertical pressure and wellbore structure;

[0230] The theoretical casing pressure variation curve is generated according to the theoretical casing pressure value.

[0231] In some embodiments of the present invention, predicting the overflow risk of the target oil and gas well according to the comparison result of the actual circulation volume change curve and the theoretical circulation volume change curve and the comparison result of the actual casing pressure change curve and the theoretical casing pressure change curve includes:

[0232] When the difference between the actual circulation volume change curve and the theoretical circulation volume change curve is greater than a first preset threshold, and the difference between the actual casing pressure change curve and the theoretical casing pressure change curve is greater than a second preset threshold, performing pressure control operation on the target oil and gas well;

[0233] When the difference between the bottom hole pressure and the formation fracture pressure is greater than a third preset threshold, an overflow alarm of the target oil and gas well is issued.

[0234] In some embodiments of the present invention, an early warning method for oil and gas well overflow further includes:

[0235] The pool volume fluctuation data caused by drilling tool activity is calculated based on the drilling tool lifting speed or lowering speed, drilling tool assembly data, and wellbore data.

[0236] In some embodiments of the present invention, an early warning method for oil and gas well overflow further includes:

[0237] The actual circulation volume change curve is corrected according to the pool volume fluctuation data.

[0238] The sensitive logging data is normalized.

[0239] Example 6:

[0240] The embodiments of the present application also provide a computer-readable storage medium capable of implementing all steps of the oil and gas well overflow early warning method in the above-mentioned embodiment. The computer-readable storage medium stores a computer program. When the computer program is executed by a processor, the computer program implements all steps of the oil and gas well overflow early warning method in the above-mentioned embodiment. For example, when the processor executes the computer program, the following steps are implemented:

[0241] At least one high-frequency radar liquid level detector is placed above a circulation tank of a target oil and gas well to collect the liquid level height of the circulation tank in real time;

[0242] generating an actual circulation volume change curve of the circulation tank according to the liquid level;

[0243] comparing the actual circulation volume change curve with a pre-generated theoretical circulation volume change curve of the circulation tank;

[0244] Compare the actual casing pressure change curve with the pre-generated theoretical casing pressure change curve;

[0245] The overflow risk of the target oil and gas well is predicted based on a comparison result between the actual circulation volume change curve and the theoretical circulation volume change curve and a comparison result between the actual casing pressure change curve and the theoretical casing pressure change curve.

[0246] In some embodiments of the present invention, the step of placing at least one high-frequency radar liquid level detector above a circulation tank of a target oil and gas well to collect the liquid level of the circulation tank in real time includes:

[0247] Measuring the time difference and the difference frequency between the transmitted wave and the reflected wave by the high-frequency radar liquid level detector;

[0248] The liquid level height is calculated according to the time difference and the difference frequency.

[0249] In some embodiments of the present invention, the step of generating the theoretical cycle volume change curve includes:

[0250] Generate inlet and outlet flow rates based on the pump stroke count and the speed at which the string is lifted or lowered;

[0251] The theoretical cycle volume change curve is generated according to the inlet and outlet flow rates.

[0252] In some embodiments of the present invention, the step of generating the theoretical casing pressure variation curve includes:

[0253] Calculate theoretical casing pressure value based on vertical pressure and wellbore structure;

[0254] The theoretical casing pressure variation curve is generated according to the theoretical casing pressure value.

[0255] In some embodiments of the present invention, predicting the overflow risk of the target oil and gas well according to the comparison result of the actual circulation volume change curve and the theoretical circulation volume change curve and the comparison result of the actual casing pressure change curve and the theoretical casing pressure change curve includes:

[0256] When the difference between the actual circulation volume change curve and the theoretical circulation volume change curve is greater than a first preset threshold, and the difference between the actual casing pressure change curve and the theoretical casing pressure change curve is greater than a second preset threshold, performing pressure control operation on the target oil and gas well;

[0257] When the difference between the bottom hole pressure and the formation fracture pressure is greater than a third preset threshold, an overflow alarm of the target oil and gas well is issued.

[0258] In some embodiments of the present invention, an early warning method for oil and gas well overflow further includes:

[0259] The pool volume fluctuation data caused by drilling tool activity is calculated based on the drilling tool lifting speed or lowering speed, drilling tool assembly data, and wellbore data.

[0260] In some embodiments of the present invention, an early warning method for oil and gas well overflow further includes:

[0261] The actual circulation volume change curve is corrected according to the pool volume fluctuation data.

[0262] The various embodiments in this specification are described in a progressive manner. Similar portions between the various embodiments can be referenced to each other. Each embodiment focuses on the differences between the other embodiments. In particular, the hardware + program embodiments are generally similar to the method embodiments, so their description is relatively simple. For relevant portions, refer to the description of the method embodiments.

[0263] The foregoing description of this specification describes specific embodiments. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims can be performed in an order different from that described in the embodiments and still achieve the desired results. Furthermore, the processes depicted in the accompanying drawings do not necessarily require the specific order shown or the sequential order to achieve the desired results. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0264] Although the present application provides method operation steps such as embodiments or flowcharts, more or fewer operation steps may be included based on conventional or non-creative work. The order of steps listed in the embodiments is only one way of executing the steps among many steps and does not represent the only execution order. When an actual device or client product is executed, it can be executed in the order shown in the embodiments or the drawings or in parallel (for example, in a parallel processor or multi-threaded processing environment).

[0265] For the convenience of description, the above devices are described in terms of functions divided into various modules. Of course, when implementing the embodiments of this specification, the functions of each module can be implemented in the same or multiple software and / or hardware, or the modules that implement the same function can be implemented by a combination of multiple sub-modules or sub-units, etc. The device embodiments described above are merely schematic. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0266] Those skilled in the art will also appreciate that, in addition to implementing the controller in pure computer-readable program code, it is entirely possible to implement the same functionality by logically programming the method steps in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, embedded microcontrollers, and the like. Therefore, such a controller can be considered a hardware component, and the devices included therein for implementing various functions can also be considered structures within the hardware component. Alternatively, the devices for implementing various functions can be considered both software modules implementing the method and structures within the hardware component.

[0267] In a typical configuration, a computing device includes one or more processors (CPUs), input / output interfaces, network interfaces, and memory.

[0268] Memory may include non-permanent storage in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. Memory is an example of a computer-readable medium.

[0269] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between the various embodiments can be referenced across them. Each embodiment focuses on the differences from the other embodiments. In particular, since the system embodiments are generally similar to the method embodiments, their description is relatively simple. For relevant parts, reference can be made to the description of the method embodiments. Throughout this specification, reference to the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the embodiments in this specification. In this specification, the schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, those skilled in the art may combine and integrate the different embodiments or examples, and features of different embodiments or examples, described in this specification, without conflict.

[0270] The above description is merely an example of the embodiments of this specification and is not intended to limit the embodiments of this specification. For those skilled in the art, various modifications and variations of the embodiments of this specification are possible. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of this specification shall be included within the scope of the claims of the embodiments of this specification.

Claims

1. An early warning method for oil and gas well overflow, characterized in that: include: At least one high-frequency radar liquid level detector is placed above a circulation tank of a target oil and gas well to collect the liquid level height of the circulation tank in real time; generating an actual circulation volume change curve of the circulation tank according to the liquid level; Comparing the actual circulation volume change curve with a pre-generated theoretical circulation volume change curve of the circulation tank; Compare the actual casing pressure change curve with the pre-generated theoretical casing pressure change curve; The overflow risk of the target oil and gas well is predicted based on a comparison result between the actual circulation volume change curve and the theoretical circulation volume change curve and a comparison result between the actual casing pressure change curve and the theoretical casing pressure change curve.

2. The oil and gas well overflow early warning method according to claim 1, characterized in that: The method of placing at least one high-frequency radar liquid level detector above a circulation tank of a target oil and gas well to collect the liquid level of the circulation tank in real time includes: Measuring the time difference and the difference frequency between the transmitted wave and the reflected wave by the high-frequency radar liquid level detector; The liquid level height is calculated according to the time difference and the difference frequency.

3. The early warning method for oil and gas well overflow according to claim 1, characterized in that: The step of generating the theoretical cycle volume change curve includes: Generate inlet and outlet flow rates based on the pump stroke count and the speed at which the string is lifted or lowered; The theoretical cycle volume change curve is generated according to the inlet and outlet flow rates.

4. The early warning method for oil and gas well overflow according to claim 1, characterized in that: The step of generating the theoretical casing pressure variation curve includes: Calculate theoretical casing pressure value based on vertical pressure and wellbore structure; The theoretical casing pressure variation curve is generated according to the theoretical casing pressure value.

5. The early warning method for oil and gas well overflow according to claim 1, characterized in that: Predicting the overflow risk of the target oil and gas well according to a comparison result of the actual circulation volume change curve and the theoretical circulation volume change curve and a comparison result of the actual casing pressure change curve and the theoretical casing pressure change curve, including: When the difference between the actual circulation volume change curve and the theoretical circulation volume change curve is greater than a first preset threshold, and the difference between the actual casing pressure change curve and the theoretical casing pressure change curve is greater than a second preset threshold, performing pressure control operation on the target oil and gas well; When the difference between the bottom hole pressure and the formation fracture pressure is greater than a third preset threshold, an overflow alarm of the target oil and gas well is issued.

6. The oil and gas well overflow early warning method according to any one of claims 1 to 5, characterized in that: Also includes: The pool volume fluctuation data caused by drilling tool activity is calculated based on the drilling tool lifting speed or lowering speed, drilling tool assembly data, and wellbore data.

7. The oil and gas well overflow early warning method according to claim 6, characterized in that: Also includes: The actual circulation volume change curve is corrected according to the pool volume fluctuation data.

8. An early warning device for oil and gas well overflow, characterized in that: include: A liquid level detector setting module is used to set at least one high-frequency radar liquid level detector above the circulation tank of the target oil and gas well to collect the liquid level height of the circulation tank in real time; An actual circulation curve generating module, configured to generate an actual circulation volume change curve of the circulation tank according to the liquid level; a first curve comparison module, configured to compare the actual circulation volume change curve with a pre-generated theoretical circulation volume change curve of the circulation tank; The second curve comparison module is used to compare the actual casing pressure change curve with the pre-generated theoretical casing pressure change curve; The overflow risk prediction module is used to predict the overflow risk of the target oil and gas well based on the comparison results of the actual circulation volume change curve and the theoretical circulation volume change curve and the comparison results of the actual casing pressure change curve and the theoretical casing pressure change curve.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the steps of the oil and gas well overflow early warning method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the oil and gas well overflow early warning method according to any one of claims 1 to 7 are implemented.

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