117 results about "Bottom hole pressure" patented technology

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 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 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.

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.

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 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 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.

The invention relates to an ultra-deep water narrow window pressure control well drilling hydraulic parameter design method, which comprises the following steps: researching the migration condition of rock debris from rock debris particle stress analysis, calculating the rock debris particle lifting critical return speed and the rock debris particle rolling critical return speed, taking the minimum value as the critical return speed of a certain well section, and taking the maximum value of the whole well section as the critical return speed of a certain well section. According to the method, the minimum rock-carrying displacement is taken as the minimum rock-carrying return speed of the whole well section, so that the obtained minimum rock-carrying displacement meets the condition of the whole well section, especially for a horizontal well, the borehole cleaning effect of the whole well section is ensured, and the change trend is more easily observed on site by drawing the change curve of the bottom hole pressure and the rock debris concentration along with the displacement; therefore, the displacement can be adjusted according to the displacement corresponding to the minimum value of the bottom hole pressure, the effect of ultra-deep water narrow window pressure control drilling is achieved, and guarantee is provided for safety and well control work.

The invention relates to the technical field of oil production engineering, in particular to a staged fracturing pump stopping test oil well packer and a control system thereof.The staged fracturing pump stopping test oil well packer comprises a central pipe, the upper end and the lower end of the central pipe are connected with an upper connector and a lower connector respectively, a rubber barrel is arranged on the periphery of the central pipe, and a thin groove is formed in the position, corresponding to the rubber barrel, of the central pipe; a traditional through hole is replaced by the thin groove, high-pressure fluid in the rubber sleeve can only be slowly decompressed through the thin groove after a pump is stopped, it is ensured that the rubber sleeve is kept in an expansion sealing state in a testing period, intersection fluid channeling is avoided, and pressure drop data of a well mouth and a well bottom truly reflects the characteristics of cracks and stratums; meanwhile, after the test is finished and the pressure of the high-pressure fluid in the central pipe is reduced to a certain value, the internal and external pressure difference of the first through hole pushes the piston to move upwards so as to open the second through hole, the fluid in the rubber sleeve can be rapidly discharged through the second through hole, the rubber sleeve rapidly shrinks and resets, the deblocking time is greatly shortened, and the single well fracturing operation efficiency is improved.

The invention provides a fractured-vuggy gas reservoir bottom hole flowing pressure calculation method considering fractured water evolution, and belongs to the field of oil and gas field development. In order to solve the problems that in a fracture-vug type gas reservoir, a fracture water body participates in seepage, and pressure response is complex, a coupling calculation process between a water body-fracture system and flowing bottomhole pressure is established. According to the method, a fracture water infiltration mechanism is introduced, the change of the fracture water content state along with the production process is dynamically described, a formation pressure iterative calculation model considering the water supply influence is constructed on the basis, and then hourly calculation of the flowing bottomhole pressure is achieved. The method only depends on conventional production data and basic geological parameters, the calculation process is clear, and the physical significance of the parameters is clear. Through comparison of example calculation and field actual measurement of flowing bottomhole pressure data, the result shows that the method can reasonably reflect the change characteristics of the bottomhole pressure in the production process of the gas well of the fracture-vug type gas reservoir, and technical support can be provided for dynamic analysis and production management of the fracture-vug type gas reservoir.

A device and process capable of early warning of density reduction of drilling fluid at the bottom of a casing belongs to the technical field of well control in a well shaft and comprises an early warning connector, a casing body, a wellhead receiver and a ground decoder, the early warning connector is arranged at the bottom of the casing body and sends signals to the wellhead receiver, and the wellhead receiver is connected with the ground decoder. After the density of the drilling fluid passing through the early-warning connector has a decline sign, the early-warning connector sends out a signal, the signal is transmitted to a well mouth through the casing body or the casing accessory, and after the well mouth receiver receives the signal, the signal is decoded through the ground decoder to judge that the overflow phenomenon exists in the underground technical casing. When the device is tripped into the bottom of the technical casing, the device can convert the change of the bottom pressure of the well bottom casing into a signal, the signal is uploaded to a well mouth by the technical casing, the change of the well bottom pressure is judged after a well mouth device decodes, and the process finds overflow at the first time, so that technical support is provided for perfecting the one-time well control problem, and the well control safety of well drilling is guaranteed to the maximum extent.

The invention relates to the technical field of shale gas well productivity prediction, and provides a shale gas well productivity prediction method, system, device and medium, the method comprises the following steps: constructing a single well bottom pressure prediction curve of a shale gas well, the bottom pressure prediction curve being a relation curve of bottom pressure and time corresponding to different production days of a single well; constructing a single well productivity prediction curve, wherein the single well productivity prediction curve is a relation curve between the total cumulative gas production and the bottom hole pressure and a relation curve between the total cumulative liquid production and the bottom hole pressure; using the single well bottom hole pressure prediction curve and the single well productivity prediction curve to obtain a relation between the total cumulative liquid production capacity and the total cumulative gas production capacity and the number of production days; and predicting the productivity of the shale gas well by using the total cumulative liquid yield and the relational expression between the total cumulative gas yield and the number of production days. The method can predict the productivity of the shale gas well based on the production characteristics of different stages.

This invention relates to a system and method for inverting formation cavity volume during well gas invasion, belonging to the field of petroleum drilling engineering technology. The system includes a wellbore throttling and circulation pressure control section, a throttling response parameter acquisition section, and multiphase flow simulation software. Using this system, three wellbore throttling response parameters—wellhead back pressure, inlet flow rate, and outlet flow rate—can be acquired. Then, based on a multiphase flow model, bottom hole pressure, gas dissolution rate, and gas invasion flow rate are predicted. Finally, the formation cavity volume is inverted using a reservoir model and gas state equations. This method fully utilizes field-obtainable parameters, eliminating the need for extensive data training, and is simple, efficient, and real-time. Furthermore, the method acquires relevant parameters during pressure control measures, which helps to curb gas invasion development. This invention enables the calculation of formation cavity volume after gas invasion occurs in the wellbore, providing theoretical support for decision-making regarding pressure-controlled drilling and well control measures in such formations.

The invention discloses an oil and gas collecting device with bottom hole pressure compensation and backflow control functions, which is applied to the technical field of oil and gas collection, and comprises a large four-way joint, an operation shut-in valve, a first small four-way joint, an operation heightening flange and a small annular communicating pipe, the lower end of the large four-way joint is connected with an outer layer pipe, and the upper end of the large four-way joint is connected with the operation shut-in valve; the upper end of the operation well shut-in valve is connected with a first small four-way joint, the upper end of the first small four-way joint is connected with an operation heightening flange, the upper end of the operation heightening flange is connected with a third gate valve, the side face of the large four-way joint is communicated with one end of a small annular communicating pipe, and the other end of the small annular communicating pipe is communicated with the side face of the first small four-way joint. And the outer-layer pipe, the middle pipe, the small-diameter pipe and the bottom hole pressure control assembly are arranged underground from outside to inside. According to the invention, the problem of flooding of deep-sea oil and gas wells, ultra-deep wells and low-pressure wells and the problem of long-term effective drainage and production of liquid producing wells can be solved.

The invention belongs to the technical field of oil and gas exploitation, and relates to a method, a system and equipment for determining formation starting pressure carbon absorption parameters and a medium. According to the method, the carbon injection pressure difference is obtained according to the flowing bottomhole pressure, the carbon absorption curve is established according to the daily carbon injection amount and the carbon injection pressure difference, the slope of the carbon injection curve visually represents the stratum carbon absorption index, and the stratum carbon absorption capacity can be rapidly and more accurately evaluated; the starting pressure of the carbon injection stratum is obtained according to the carbon absorption curve, and a basis is provided for model selection of a carbon injection compressor or a carbon injection pump; according to the carbon injection formation starting pressure and the formation static pressure, the carbon injection minimum bottom hole pressure is obtained; the carbon absorption index is obtained according to the flowing bottomhole pressure, the daily carbon injection amount and the starting pressure of the carbon injection stratum, the stratum carbon absorption index accurately represents the stratum carbon absorption capacity, and a powerful basis can be provided for ground engineering construction, carbon dioxide injection oil displacement recovery ratio improving scheme compilation, carbon dioxide injection geological design and the like.

The present application relates to the technical field of geothermal well, particularly to a geothermal well underbalanced drilling, system and prediction and installation method, wherein the geothermal well underbalanced drilling comprises a casing; a drill pipe coaxially arranged with the casing, an outer diameter of the drill pipe being smaller than an inner diameter of the casing, and an annulus existing between the drill pipe and the casing; and a gas injection pipe arranged outside the casing and in communication with the annulus, the gas injection pipe being used for injecting variable flow of gas to mix with drilling fluid in the annulus to form gas-liquid two-phase flow. The gas injection pipe is in communication with the annulus of the casing, the mixed density of the liquid in the annulus is changed by injecting gas into the casing, so that the bottom hole pressure is less than the formation pressure, thereby achieving the effect of underbalanced drilling, improving the drilling speed, and preventing a large amount of drilling fluid from leaking into the formation fracture.

This invention relates to a time-varying evolution inversion method for fracture morphology, net pressure, and minimum geostress, belonging to the field of petroleum technology. The method includes: acquiring on-site bottomhole pressure data, monitoring well information, and LF-DAS data during fracturing operations; discretizing the fracture along its length into several units based on the three-dimensional displacement discontinuity method and constructing a net pressure distribution matrix; using a pre-constructed mechanical response relationship between net pressure and fracture width distribution to solve for the fracture width distribution corresponding to the current net pressure distribution; calculating the axial strain response of the fracture at the monitoring well based on the fracture width distribution to form a forward model for pressure-fracture width-strain solution; iteratively updating the fracture half-length and net pressure using the least squares method, constructing a residual between the inverted strain and the on-site strain to minimize the residual, and obtaining the time-varying inversion results for the fracture half-length and net pressure. The time-varying evolution process of minimum geostress can be characterized by the difference between the on-site bottomhole pressure and the inverted net pressure.