160 results about "Bottom hole pressure" patented technology

The invention discloses a while-drilling pressure monitoring and regulating device for a complex fractured reservoir, and relates to the technical field of well drilling automatic control, and the while-drilling pressure monitoring and regulating device comprises a data acquisition module which comprises a micro-resistivity imaging logging device and a well drilling data acquisition device; the micro-resistivity imaging logging device is used for acquiring well wall imaging data to obtain crack characteristic parameters; the drilling data acquisition device is used for acquiring operation parameters in the drilling process; the data analysis module is used for evaluating the total fracture pressure, calculating the pressure gradient while drilling and constructing a seepage model to obtain the fracture flow according to the fracture characteristic parameters and the operation parameters; and the self-adaptive control module is used for calculating the optimal bottom hole pressure according to the fracture flow in combination with the operation parameters, and controlling the pressure while drilling based on the optimal bottom hole pressure. Real-time evaluation of the fracture pressure state and self-adaptive regulation and control of the bottom hole pressure can be achieved, and the safety of the drilling process is effectively improved.

The invention relates to the field of geothermal well drilling, and discloses a gas lift reverse circulation well drilling method, which comprises the following steps of: determining formation pore pressure based on the height of a static water level in a well; setting the annulus bottom hole pressure to be equal to the formation pore pressure, and determining the reference dynamic water level height of the drilling fluid according to the annulus bottom hole pressure, the relevant parameters of the gas lift reverse circulation drilling equipment and the relevant parameters of the drilling fluid; based on the reference dynamic water level height, a first target dynamic water level height is determined, in the drilling process, the dynamic water level height of the drilling fluid is controlled to be the first target dynamic water level height, and the first target dynamic water level height is lower than the reference dynamic water level height. By controlling the dynamic water level height of the drilling fluid in the drilling process to be lower than the corresponding reference dynamic water level height when the annulus bottom hole pressure is equal to the formation pore pressure, the annulus bottom hole pressure can be controlled to be lower than the formation pore pressure, the drilling process is kept in an unbalanced state, the drilling fluid can be prevented from leaking into the formation, and the drilling efficiency is improved. The heat storage is damaged.

The invention discloses a method for evaluating the crude oil utilization rate during shale oil in-situ heating modification exploitation, and is applied to the field of oil development. The method comprises the following steps: (1) constructing a three-dimensional grid model of shale oil reservoirs between two horizontal wells, and determining parameters such as initial temperature, initial fluid pressure, initial porosity, initial oil saturation, initial gas saturation, initial water saturation and initial dissolved gas volume of three-dimensional grid units of each reservoir; (2) determining the pressure of each reservoir three-dimensional grid unit when the fluid pressure is balanced according to the shale oil layer section bottom hole pressure and the reservoir displacement pressure gradient; (3) according to the characteristics of a temperature field, a pressure field and the like of the in-situ heating shale oil reservoir, obtaining three-dimensional grid unit temperature and instantaneous fluid pressure parameters of each reservoir, and determining porosity and fluid saturation at each time point; and (4) according to the instantaneous fluid pressure and the balanced fluid pressure of the three-dimensional grid unit of each reservoir, determining the oil, gas and water production quantity and the production rate of the grid unit of each reservoir in combination with the oil, gas and water saturation.

The invention provides a shale oil well pressure recovery well test interpretation method and device and electronic equipment.The method comprises the steps that effective well shut-in pressure test data and well entering time of a pressure gauge are obtained, the effective well shut-in pressure test data are well bottom pressure data after well shut-in and after the pressure gauge is lowered to the target test depth away from a well opening, and the well entering time is obtained; the well entering time is the time required for lowering the pressure gauge to a target test depth from a well mouth after the well is closed; obtaining well shut-in starting time and a pressure gradient in a well entering process of the pressure gauge; according to the pressure gradient, fluid pressure data at the well shut-in starting time and the target test depth from the well mouth are calculated to serve as supplementary pressure data; according to the effective shut-in pressure test data, the well entering time and the supplementary pressure data, a complete pressure recovery well test curve is determined; and on the basis of the complete pressure recovery well test curve, pressure recovery well test interpretation is carried out. According to the method, the problem of data missing in the early stage of well shut-in testing can be solved, the integrity of a pressure recovery well testing curve is guaranteed, and the accuracy of pressure recovery well testing interpretation is improved.

The invention relates to the field of petroleum and natural gas extraction, and discloses a self-adaptive temporary plugging agent for plugging irregular holes and a preparation method and application thereof. The temporary plugging agent comprises a flexible material and a ductile material layer wrapping the flexible material. Wherein the tough material layer is made of polyurea, and the thickness of the tough material layer is larger than or equal to 0.5 mm. The temporary plugging agent is of a double-layer structure which is soft inside and tough outside, the inner layer is made of a flexible material and can deform easily, the outer layer is made of a tough material, the bottom hole pressure is within the compressive strength of the temporary plugging agent, and a tough material wrapping layer can deform sufficiently along with the flexible material of the inner layer and cannot be damaged.

The invention provides a method and a device for predicting a steam cavity in steam flooding by using an overlap factor, and belongs to the technical field of oil field oil extraction. The method comprises the following steps: determining an incidence relation between wellhead production characteristics of a first production well and a well bottom average temperature value, and determining a well bottom average temperature value of a second production well according to wellhead production characteristics of the second production well by utilizing the incidence relation; determining overlap factors of different displacement layer sections of the first production well; weighting the well bottom average temperature value of the second production well by using the overlay factor of each displacement layer section, and obtaining the well bottom correction temperature of each displacement layer section in the second production well in a one-to-one correspondence manner; and comparing the well bottom correction temperature of the second production well with the well bottom temperature of the steam injection well in the well group where the second production well is located, comparing the well bottom pressure of the second production well with the well bottom pressure of the steam injection well, and identifying the steam cavity of each displacement layer section of the second production well. By means of the method, rapid, accurate and low-cost recognition of the steam cavity is achieved.

The invention discloses a coal bed gas horizontal well energy increasing and well repairing method. The method comprises the following steps that S1, basic data of a well are collected, and production data of the well are analyzed; s2, configuring an extra-low pressure energizing well repair scheme; s3, a ground process of a continuous pipe nitrogen foam sand washing process; s4, nitrogen foam well washing is carried out; s5, circulating liquid desanding is conducted till the sand content meets the preset condition, and well repairing is ended. The method is suitable for the technical field of unconventional gas field development, nitrogen is injected into a production layer to increase energy, the well bottom pressure is increased, nitrogen foam well flushing fluid with certain viscosity is adopted as well flushing fluid, the density of the nitrogen foam well flushing fluid is designed according to the well bottom pressure, and the well flushing efficiency is improved; a normal circulation channel is established, solid particles in a shaft are discharged out of the shaft, perforation blast holes are dredged at the same time, the effects of purifying the shaft and improving gas production and water production are achieved, a tubular column is fixed, operation under pressure can be achieved, and production halt and operation time can be greatly shortened.

The invention provides a shale gas well inter-well pressure channeling identification method, system, device and medium, the shale gas well inter-well pressure channeling identification method comprises the following steps: carrying out well test analysis in a pump stop pressure drop stage after fracturing, and collecting data; the bottom hole pressure is calculated, and pressure data oscillation caused by the water hammer effect is eliminated; drawing a pressure difference and pressure difference derivative double logarithmic curve based on the bottom hole pressure data; establishing a shale gas well non-uniform fracture multi-zone coupling well test seepage model; the model parameters are adjusted, a pressure difference and pressure difference derivative double logarithmic curve is fitted, and when the model result is close to the drawn pressure difference and pressure difference derivative double logarithmic curve, the crack parameters of the model parameters are obtained through inversion; judging whether the crack parameter is too high or not; and determining the relationship between the child well group and the mother well group, analyzing the pressure difference and pressure difference derivative curve morphological characteristics of the fracture parameter high section, and judging whether pressure channeling occurs or not. The system can realize the method. According to the method, the inter-well pressure channeling identification efficiency in the well group synchronous fracturing period can be improved.

The invention relates to a method for treating shale oil crack wall surfaces by using carbon nanotubes to increase the heat transfer capacity of a reservoir, a plurality of horizontal wells are drilled from the ground, the horizontal sections of the horizontal wells form three parallel well rows, the uppermost well row and the lowermost well row are heating wells, and the middle well row is a production well. The fracturing fluid carrying the proppant is injected into the heating well and the production well with the displacement greatly exceeding the stratum absorption capacity, the bottom hole pressure is larger than the stratum fracture pressure, hydraulic fracturing is carried out, a tensional fracture area and a communication well group are generated, and meanwhile it is guaranteed that fractures are not closed after the proppant is filled. Under the condition that the pressure is lower than the formation fracture pressure, a weak acid solution is slowly squeezed into the heating well and the production well, the well wall and the crack wall face are treated, and a large number of corrosion micropores are formed. And under the condition that the pressure is lower than the stratum fracture pressure, a weak acid solution added with the carbon nano tubes is squeezed into the heating well and the production well, so that the carbon nano tubes are adsorbed or filled in the corrosion micropores, and the micropores where the carbon nano tubes are attached are formed. And high-temperature steam is circularly introduced into the heating well and the production well to heat the oil shale stratum. After heating for a certain time, stopping steam injection of the production well, and changing into production; and continuously injecting steam into the heating well. The method is suitable for an oil shale underground in-situ conversion exploitation technology, and is also suitable for geothermal exploitation and heavy oil thermal exploitation.

The invention relates to the technical field of multi-layer commingling production, and discloses a multi-layer commingling production interlayer interference mechanism calculation method for different types of gas reservoirs, which comprises the following steps of: constructing a single-layer dimensionless mathematical model for respectively representing each reservoir of a commingling production well, and solving a bottom hole pressure solution of the corresponding model; the known gas production rate of the commingled production well is input into the model, and a theoretical well bottom pseudo-pressure value is calculated through the superposition principle; performing historical fitting on the actual well bottom pseudo-pressure value and the theoretical well bottom pseudo-pressure value of each reservoir to obtain characterization parameters; calculating to obtain the predicted gas production rate of the corresponding model in combination with the characterization parameters, and summing the gas production rate of the commingled production well; the abscissa material equilibrium time, the ordinate regularization yield and the calculation formula of the Blasingame curve are obtained, and the gas production rate of the commingling production well is obtained through calculation; according to the obtained gas production rate of the commingled production well at the current time step, determining the influence of the reservoir interference between the obtained gas production rate of the commingled production well during multi-layer commingled production and the gas production rate of the commingled production well obtained through summation.

The invention relates to a pressure-controlled drilling formation pressure calculation and control method and system based on multi-field coupling, and belongs to the field of oil exploration and development. The method comprises the steps that 1, an industrial personal computer is connected with a logging instrument, and basic data needed by calculation are obtained in real time; 2, shaft-stratum space domain grids are divided, and drill rod and annulus temperature distribution and stratum temperature distribution at different distances from a borehole are calculated; 3, considering the thermal-fluid-solid multi-field coupling influence, and calculating well circumference stresses at different well depth positions in elastic-plastic regions; 4, solving a real-time formation pore pressure profile after multi-factor coupling correction; 5, calculating real-time stratum fracture pressure profiles and collapse pressure profiles at the well walls at the different well depth positions after multi-factor coupling correction in the elastic-plastic areas; and 6, determining a bottom hole pressure control standard, calculating in real time based on a shaft hydraulic parameter calculation model, and controlling the wellhead back pressure in real time through an industrial personal computer. The method can effectively improve the calculation precision of the formation pressure during the pressure-controlled drilling period.

A method comprises retrieving attributes of a blowout well and a relief well and simulating a dynamic kill of a blowout from the blowout well via a kill mud pumped down through the relief well, wherein the simulating comprises determining a flowing bottom hole pressure for the blowout well and the relief well based on an intersection of a reservoir inflow performance relationship (IPR) curve and a wellbore vertical lift (VLP) curve.

The invention discloses a gas lift reverse circulation bottom hole pressure prediction method. The method comprises the steps that regional grid division is carried out; calculating unit parameters; determining an iterative calculation position; and outputting bottom hole pressure. The gas lift reverse circulation drilling technology is one of typical shaft bottom negative pressure drilling technologies, and the technology can greatly reduce shaft circulation pressure consumption, reduce the shaft bottom hold-down effect and effectively reduce the probability of well leakage. The invention aims to deduce a calculation method for predicting the gas injection point pressure and the bottom hole pressure under the gas lift reverse circulation, which provides important reference for predicting the bottom hole pressure and preventing well leakage, and has important significance for the development of the gas lift reverse circulation technology.

This invention relates to the field of exploration and development, and discloses a method, system, and equipment for quantitative analysis of friction resistance in directional drilling. The method includes: acquiring logging information and drill bit speed in the drilled section; constructing a drilling speed prediction model using the drill bit speed and the composite drilling data; determining a bottom hole pressure prediction model based on the directional drilling data and the drilling speed prediction model; combining the bottom hole pressure prediction model with the surface pressure to determine a drill string axial friction resistance model; and calculating the axial friction resistance in the real-time directional drilling process using the drill string axial friction resistance model based on the logging information and drill bit speed. The quantitative friction resistance analysis method disclosed in this application solves the problem of difficulty in accurately assessing bottom hole pressure and axial friction resistance, enabling dynamic assessment of theoretical bottom hole pressure and axial friction resistance. It allows for full-process monitoring and post-drilling analysis of sliding drilling, providing a basis for improving the bottom hole drill string load condition.

The invention relates to the technical field of drilling engineering, and discloses a method, device and equipment for controlling pressure and downloading an instruction while drilling, according to the method, a well bottom pressure negative fluctuation of a downloading instruction while drilling is balanced in a mode of constructing a well mouth back pressure real-time prediction model of a target area and calculating real-time target back pressure, and in the process, the real-time target back pressure is calculated; key parameters of a wellhead back pressure real-time prediction model are determined by acquiring standing pressure parameters and bottom hole pressure parameters in a non-control instruction downloading process, namely, wellhead back pressure adjustment proportion parameters are determined, so that initialization of the wellhead back pressure real-time prediction model is completed, and real-time measurement standing pressure in a pressure control instruction downloading process is acquired, so that the wellhead back pressure real-time prediction model is obtained. The real-time target return pressure is calculated through the constructed wellhead return pressure real-time prediction model, and the wellhead pressure is adjusted in real time according to the real-time target return pressure, so that the bottom hole pressure negative fluctuation of the instruction transmitted while drilling is balanced, the downhole complex occurrence probability is reduced, and the drilling safety is further guaranteed.

The invention relates to the field of oil development engineering, in particular to a method, a system and equipment for controlling water content rise of an oil well of an ultra-low permeability reservoir. The problems that an existing method is short in validity period and causes pollution to stratums and the environment are solved. The method comprises the following steps: screening oil wells based on basic data to obtain a target oil well; pressure distribution of plane radial flow and pressure distribution of gas-phase unidirectional flow of the gas cap of the target oil well are calculated; pressure distribution of plane radial flow and pressure distribution of liquid-phase unidirectional flow of the oil layer of the target oil well are calculated; the position of the perforation is further calculated; calculating a roof-remaining reference value based on the stratigraphic dip angle, and calculating a roof-remaining thickness based on the roof-remaining reference value; setting the perforations based on the positions of the perforations and the thickness of the top, and adjusting the pressure distribution of the perforations by adjusting the bottom hole pressure based on practice so as to adjust the water content rising speed. The invention has the advantages of long period of validity and no pollution.

The invention relates to a stratum karst cave volume inversion system and method in a drilling gas cut process, and belongs to the technical field of petroleum drilling engineering, and the system comprises a shaft throttling circulation pressure control part, a throttling response parameter acquisition part and a multiphase flow simulation software part. By means of the system, three wellhead throttling response parameters including wellhead back pressure, inlet flow and outlet flow can be obtained, then bottom hole pressure, gas dissolution amount and gas cut flow are predicted based on a multiphase flow model, and stratum karst cave volume inversion is conducted through an oil reservoir model and a gas state equation. According to the method, on-site available parameters are fully utilized, a large amount of data training is not needed, and the method has the advantages of being simple, efficient and high in real-time performance; in addition, related parameters are obtained in the process of taking pressure control measures, and the method has a restraining effect on gas cut development. By means of the method, the volume of the stratum karst cave can be calculated after gas cut occurs in the shaft, and theoretical support is provided for stratum pressure control well drilling and well control measure decision making.

The invention relates to the technical field of oil and gas field drilling and logging, and particularly discloses a formation pressure monitoring method and system based on drilling and logging real-time data fusion. The formation pressure monitoring method comprises the following steps that S1, geological data of a drilling well adjacent to a target well in a geological block where the target well is located are obtained, and formation factors of the geological block are obtained; s2, comprehensive real-time well drilling data of the target well are obtained, and a dynamic factor of the target well is solved; s3, constructing a formation pressure evaluation model of the target well by using the formation factor and the dynamic factor and utilizing a formation pressure monitoring model, and taking the formation pressure evaluation model as a real-time monitoring standard of the target well; and S4, the dynamic factors and the bottom hole pressure of the target well are monitored in real time, and the formation pressure can be monitored in real time according to the formation pressure evaluation model of the target well. No underground sensor is needed, and the formation pressure can be monitored in real time only through well gas measurement data.

The present application relates to a kind of design methods of cementing annular slurry column, comprising the following steps: 1) collecting the leakage parameter of the weakest formation in the formation to be cemented, the leakage parameter of the second weakest formation, the bottom hole leakage parameter and the maximum formation pressure parameter;2) calculate the maximum pressure bearing parameter at the weakest formation when cementing operation is bumped, the maximum pressure bearing parameter at the second weakest formation when cementing operation is bumped, the maximum pressure parameter that bottom hole bears when cementing operation is bumped and the bottom hole pressure parameter when tail slurry gelatinization loses weight during cementing operation;3) according to the leakage parameter of the weakest formation, the leakage parameter of the second weakest formation, the bottom hole leakage parameter and the maximum formation pressure parameter, the maximum pressure bearing parameter at the weakest formation when cementing operation is bumped, the maximum pressure bearing parameter at the second weakest formation when cementing operation is bumped, the maximum pressure parameter that bottom hole bears when cementing operation is bumped and the bottom hole pressure parameter when tail slurry gelatinization loses weight during cementing operation, it is judged whether annular slurry column is designed reasonably.

This invention provides a method for dynamic prediction of cement slurry weight loss in long inclined vertical well sections. The method includes: calculating the effective bottom hole pressure P during the cement slurry weight loss process. b Effective pressure at the bottom of the well, P b The calculation formula is: P b = P0 + P1; where P0 is the liquid column pressure at the top of the cement slurry; P1 is the effective pressure of the cement slurry; the calculation of the effective pressure P1 of the cement slurry includes determining the remaining pressure P after the cement slurry gels and loses weight, taking into account the eccentricity of the tailpipe and the downhole temperature and pressure. sy The residual pressure P after the cementation and weight loss of the mud obtained by this invention sy The calculations are more consistent with the gelation and weight loss characteristics of cement slurry under complex downhole conditions, effectively ensuring the accuracy of dynamic prediction of cement slurry weight loss.

The present invention relates to the technical field of pressure-controlled drilling for oil and gas development, and in particular to a pressure-controlled drilling method for a formation with coexisting leakage and spillage based on a controllable pressure window. The technical solution comprises the following steps: determining the formation pressure coefficient and pressure window; judging whether the pressure window is safe based on monitoring data and the density of the drilling fluid used on site; if the pressure window is within the safe pressure window, maintaining normal drilling; otherwise, entering the controllable safety window calculation process; determining the maximum controllable leakage rate based on the actual leakage volume and the on-site drilling fluid mud supply capacity; determining the maximum controllable overflow rate based on the on-site wellhead back pressure control capacity; forming a controllable safety density window; after obtaining the controllable drilling fluid safety density window and the bottomhole pressure range, updating the safety density window, and drilling under the condition of maintaining micro-leakage and micro-overflow in the coexisting leakage formation. The present invention implements a pressure-controlled drilling method within the controllable pressure window, thereby ensuring operational safety.

The invention discloses a coupling method of a shale gas multi-scale percolation mechanism. The coupling method comprises the following steps: establishing a percolation equation based on a quadruple-pore shale matrix model of spherical matrix particles and columnar matrix bars; establishing a seepage equation considering a gas slippage effect, a diffusion effect and adsorption gas desorption; establishing a seepage equation considering the starting pressure gradient and the crack stress sensitive effect; establishing a seepage equation considering desorption of adsorbed gas on the surfaces of the organic matter particles and diffusion of dissolved gas in the organic matter particles; carrying out simultaneous solution on a total seepage equation obtained by coupling the boundary conditions and the pore model characteristics to obtain a bottom hole pressure solution of the fractured horizontal well; drawing a well testing curve chart according to the well bottom pressure solution of the fractured horizontal well; and fitting measured data by adjusting model parameters to obtain inversion results of reservoir parameters and fracture geometric parameters. According to the method, the seepage rule of the shale gas reservoir fractured horizontal well is more comprehensively simulated, and the interpretation precision and range of well testing parameters are improved.

The invention relates to the technical field of oil and gas reservoir permeation enhancement and carbon dioxide geological sequestration, and discloses a laumontite-containing reservoir permeation enhancement and carbon dioxide sequestration strengthening method. The method comprises the following steps: firstly, screening a reservoir with the laumontite content reaching the standard and meeting thermodynamic reaction conditions; injecting carbon dioxide into the target layer by adopting a two-stage pressure control strategy; and finally, the well closing duration is dynamically controlled by monitoring the bottom hole pressure in real time and calculating the change rate of the bottom hole pressure function, and when the change rate is continuously lower than a threshold value, it is indicated that stability tends to be achieved, and well closing is stopped. By utilizing the mineralization reaction of laumonite and carbon dioxide, the carbon dioxide is converted into calcium carbonate minerals for permanent storage while effective permeation enhancement of the reservoir is realized, and the method has the advantages of small reservoir damage, high storage safety and low cost, and meets the requirements of green and low-carbon development.

The present disclosure provides a method for predicting the productivity of a direct well of a gas storage under the conditions of interwell interference and strong injection and production, comprising: obtaining basic data of a target formation of a natural gas underground gas storage; based on the basic data of the target formation of the natural gas underground gas storage and a direct well productivity prediction mathematical model, using the superposition principle to calculate the pressure superposition solution of the target direct well under the conditions of interwell interference and strong injection and production, and obtaining the bottom hole pressure solution of the target direct well of the direct well productivity prediction mathematical model; based on the bottom hole pressure solution, obtaining the production solution of the target direct well, and predicting the productivity of the target direct well in the natural gas underground gas storage. On the basis of the existing productivity prediction method, the superposition principle is used to solve the influence of interwell interference and strong injection and production on the calculation of the productivity of the direct well of the gas storage, improve the accuracy of the direct well productivity prediction mathematical model, reduce the error in the productivity calculation process, and accurately predict the productivity of the direct well of the gas storage.

The invention provides a prediction method and device for a steam cavity in steam flooding and computer equipment, and relates to the technical field of oil field oil extraction. The method comprises the steps that the incidence relation between wellhead production characteristics of a first production well and the bottom hole temperature is determined, and according to the incidence relation, the bottom hole temperature of a second production well is determined according to the wellhead production characteristics of the second production well; calculating the bottom hole pressure of the second production well; and comparing the well bottom temperature of the second production well with the well bottom temperature of the steam injection well, comparing the well bottom pressure of the second production well with the well bottom pressure of the steam injection well, and identifying a steam cavity at the well bottom of the second production well. According to the method, the incidence relation between the wellhead production characteristics and the bottom hole temperature is established by using the production data of the first production well with the bottom hole temperature monitoring data, and the bottom hole temperature of the second production well without the bottom hole temperature monitoring data is predicted by using the incidence relation. And rapid and accurate identification of the steam cavity of the second production well is realized.

This invention relates to the field of well test interpretation technology, and discloses a method and related equipment for calculating the length of large-scale natural fractures. By establishing a mathematical model of well test in a naturally fractured reservoir, calculating the real-time bottom hole pressure, and plotting the interpretation curve of the well test in the naturally fractured reservoir, the theoretical bottom hole pressure is obtained by combining the real-time bottom hole pressure and the interpretation curve, and the theoretical well test curve is plotted. Finally, the natural fracture length is obtained by fitting the theoretical and measured curves. This method overcomes the limitation of uniform fracture distribution in conventional models, is suitable for deep gas reservoirs with poor matrix properties and strong fracture heterogeneity, and avoids the problem of only being able to obtain equivalent parameters and interpreting parameters that do not reflect reality. It accurately characterizes the fracture development state and improves the accuracy of well test interpretation.

This invention discloses a real-time assessment method for bottom-hole pressure in annular multiphase flow driven by both physical models and data, comprising the following steps: S1: Establishing an annular multiphase flow mechanism model; S2: Initializing the annular multiphase flow mechanism model; S3: Calculating the prior estimate of the bottom-hole pressure at the current moment based on the physical parameters of the target well at the previous time step; S4: Calculating the theoretical riser pressure and obtaining the pressure residual; if the pressure residual is less than a threshold, the prior estimate is the final estimation result; otherwise, proceed to step S5; S5: Inputting the pressure residual and the operating characteristics of the target well into a neural network, mapping and outputting the physical parameter correction; S6: Correcting the physical parameters, performing a secondary solution, and obtaining the corrected value of the bottom-hole pressure at the current moment, which is the final estimation result; S7: Repeating steps S3-S6 to obtain the real-time assessment result of the bottom-hole pressure in annular multiphase flow. This invention can quickly and accurately assess the bottom-hole pressure of annular multiphase flow in real time.

The application provides a water injection well pressure analysis method considering the influence of fracture induced by pressure drive water injection, which comprises the following steps: step 1, establishing a water injection well pressure analysis model considering the influence of fracture induced by pressure drive water injection; step 2, solving the water injection well pressure analysis model considering the influence of fracture induced by pressure drive water injection; step 3, obtaining a water injection well double logarithmic pressure analysis curve through analysis, and judging different flow stages of the reservoir in the fracturing process according to the curve; and step 4, analyzing the bottom hole pressure response characteristics of the pressure drive water injection well, and applying the characteristics to an actual well to verify the accuracy of the established model. The water injection well pressure analysis method considering the influence of fracture induced by pressure drive water injection establishes a water injection well pressure analysis model considering the dynamic expansion of the fracture, has certain technical difficulty, and can determine the flow stage of fluid in the reservoir at different production moments.

The invention discloses a bottom hole pressure calculation method and device for fracturing construction, and the method comprises the steps: comparing the accumulated liquid amount of a target well at the current moment with the preset liquid amount of a corresponding well section position, and determining the well section position on which the accumulated liquid amount acts at the current moment according to the comparison result of the accumulated liquid amount; based on the corresponding relation table at the same moment, the liquid type, the sand concentration and the displacement of the well section position are searched in the corresponding relation table according to the accumulated liquid amount of the target well at the current moment and the acted well section position; according to the liquid type, the sand concentration and the displacement corresponding to the well section position, the corresponding pipe column friction resistance and the liquid column static pressure are calculated; and calculating the bottom hole pressure at the current moment according to the known casing pressure at the current moment, the calculated liquid column static pressure and the pipe column friction resistance. According to the method, measurement errors caused by dynamic change lag of shaft liquid distribution in a traditional method are effectively overcome, and the accuracy of shaft bottom pressure monitoring is remarkably improved.

The invention discloses a high-gas-liquid-ratio lifting method and device. The lifting method comprises the steps that a production well is selected, and a gas anchor is installed; a remote control one-way valve is mounted on the wall of the oil pipe; a bottom gas flowmeter and a bottom pressure gauge are mounted at the bottom of the production well; a remote control one-way valve on the wall of the oil pipe is closed, and well bottom gas flow, well bottom pressure and oil production data are monitored; when the gas-liquid ratio of the production well exceeds a first set threshold value or the bottom hole pressure is lower than a second set threshold value of saturation pressure, the remote control one-way valve on the oil pipe wall is opened, and annular gas enters the oil pipe; when the bottom hole pressure rises to a third set threshold value of the original formation pressure or the gas-liquid ratio decreases and is lower than a fourth set threshold value, the remote control one-way valve on the oil pipe wall is closed; and monitoring production parameters, and repeatedly executing the steps of starting the separated gas auxiliary lifting and closing the separated gas auxiliary lifting. And lifting is assisted through separated gas, the annulus pressure of an oil pipe and an oil sleeve is balanced, and safe lifting of a high-gas-liquid-ratio well is achieved.