28 results about "Wellbore instability" patented technology

This invention relates to a drilling system and method for preventing wellbore instability during drilling through goaf areas, belonging to the field of drilling machinery technology. The objective is to provide a drilling system that effectively prevents wellbore instability during drilling through goaf areas. The technical solution includes a motor, a reducer, a clutch, a square drill pipe, a rotary table, a transmission rod, a drill pipe, a guide rod, and a drill bit. The motor is connected to the upper end of the square drill pipe via the clutch and reducer. The lower end of the square drill pipe passes through the rotary table and is connected to a first universal coupling. The first universal coupling is connected to the upper end of the transmission rod via a universal joint. The lower end of the transmission rod is connected to a second universal coupling via a cross bar. The lower end of the second universal coupling is connected to the upper end of the drill pipe via a flange. A rubber sheet is connected to the lower end of the drill pipe, and a solution damper is connected below the rubber sheet. The lower end of the solution damper is connected to the upper end of the guide rod, and the lower end of the guide rod is connected to the drill bit. This invention is used for drilling through goaf areas.

The invention relates to the technical field of geologic model analysis, in particular to a coal bed gas fracturing three-dimensional well network seam network design method based on a geologic model, and the method comprises the steps: firstly constructing a three-dimensional discrete geologic model containing grid node mechanical parameters, and generating a three-dimensional dynamic induced stress potential energy tensor field; performing low-potential-energy gradient optimization calculation by using the field to obtain a shaft space topological coordinate avoiding a high-potential-energy area so as to reduce the well wall instability risk; meanwhile, fracture extension simulation is cut off through an equipotential surface threshold value in the field, and hydraulic fracture geometrical morphology parameters matched with formation energy constraint are accurately determined; and finally, integrating the parameters to generate an optimized three-dimensional well pattern seam network design scheme, and realizing efficient and safe fracturing design based on the rock mass accumulated deformation energy distribution characteristics.

This invention provides a method for preparing a polyamine that combines inhibition and solid-phase cleaning effects. Compared with existing technologies, the polyamine prepared by this invention exhibits better inhibitory and solid-phase cleaning effects under high-temperature conditions, and also demonstrates better compatibility in drilling fluids. Its application in drilling fluids can effectively solve the wellbore instability problem in highly water-sensitive shale formations, and effectively avoid drilling fluid slurry formation problems caused by drill cuttings hydration, thus ensuring wellbore stability and drilling fluid cleanliness.

This invention belongs to the field of natural gas extraction technology in deep thin coal and rock formations. It discloses a directional anti-sticking drill string assembly and drilling method for horizontal wells in deep thin coal and rock formations. A closed-loop control system is formed between the drill bit trajectory control mechanism and the wellbore dressing and anti-sticking mechanism, encompassing near-bit high-precision sensing, real-time data transmission while drilling, surface analysis feedback control, active downhole directional correction, and synchronous wellbore dressing and protection. Multi-directional gamma sensors positioned near the drill bit provide high-resolution formation information; the bend structure of the downhole power drill string provides the direction of the wellbore trajectory; the non-magnetic bearing section ensures the stability of measurement while drilling and the reliability of communication; the surface control unit enables real-time decision-making and trajectory correction; and the wellbore dressing and anti-sticking mechanism simultaneously improves wellbore stability and cuttings carrying capacity. This significantly enhances the drilling throughput and resistance to coal seam collapse in complex sections of thin coal and rock formations while ensuring trajectory controllability, reducing the risk of sticking due to wellbore instability and cuttings accumulation.

This invention discloses an inhibitory water-based foam drilling fluid system to solve the wellbore instability problem currently existing in foam drilling. The system comprises 0.5%-1.0% fluorocarbon foaming agent, 0.2%-1.0% inhibitor, 0.04%-0.2% foam stabilizer, 0.2%-0.4% thickener, 1.0%-5.0% bentonite, and water as the balance. The fluorocarbon surfactant is a fluorocarbon surfactant containing a quaternary ammonium salt cationic structure, the inhibitor is a small-molecule amine salt structure inhibitor, and the large-molecule foam stabilizer is one or more combinations of starch, cellulose, and polyacrylamide. The foaming agent provided by this invention, when applied in foam drilling, possesses both strong foaming and inhibitory properties.

Aspects of the disclosure provide a method of mitigating liquid instability in controlled intra-well cross-flow between two, or more, zones accessed by a well. One or more embodiments define new functionalities necessary for dynamic multiphase flow (MPF) simulation to model, mitigate and control liquid instability observed in a well.

The invention discloses a geomechanical method for quantitatively evaluating the well wall stability of a fractured formation, which comprises the following steps of: acquiring a crustal stress state, a rock strength parameter, a fracture occurrence and a fracture strength parameter according to seismic data, logging data and rock mechanics experimental data; according to the obtained parameters, determining the stress state of the complete rock of the target layer section and the instability index of the crack-containing rock; the instability index of the complete rock and the instability index of the crack-containing rock are solved through the stress state; the weight values of the parameters are considered, and a comprehensive instability index of the target layer section is obtained; and finally, according to the corresponding relationship between the calculated comprehensive borehole wall instability index and the instability degree, determining the borehole wall instability degree of the target interval corresponding to the instability index. According to the method, the crustal stress state, the rock strength parameter, the fracture occurrence and the fracture strength parameter are comprehensively quantified, comprehensive evaluation of the instability index is formed, and the objectivity and the accuracy of the evaluation result are improved.

The invention provides a CaCO3 / polymer-based plugging agent, a preparation method thereof and a water-based drilling fluid, the preparation method of the CaCO3 / polymer-based plugging agent comprises the following steps: S1, synthesizing CaCO3 in the presence of a modifier to obtain modified CaCO3; s2, taking the modified CaCO3 and a functional monomer as raw materials, adding a cross-linking agent, an initiator and a dispersing agent, and synthesizing a CaCO3 / polymer-based plugging agent by adopting a reversed-phase suspension polymerization method; wherein the functional monomers are styrene, acrylamide and N-vinyl pyrrolidone. The water-based drilling fluid based on the CaCO3 / polymer-based plugging agent is low in cost, has a good plugging effect, has temperature resistance and pressure bearing performance, and can solve the problem of well wall instability of a high-temperature well section.

The present disclosure provides a wellbore instability analysis method based on big data, which relates to the field of wellbore instability. The wellbore instability prediction based on big data analysis and deep learning, combined with existing wellbore instability theory and experimental research results, finds the main control factors and related factors of wellbore instability in the studied block. Based on data classification, a big data model is established to improve the accuracy of analysis and prediction through big data learning. Through the application of the big data model, the deep learning technology is used for regional wellbore instability evaluation and research, and finally the regional wellbore instability evaluation and prevention technology based on big data is formed. The wellbore instability analysis tool based on big data analysis mainly provides the safety density window for preventing wellbore instability, the control analysis of hole diameter change, the optimization of drilling fluid performance and additive dosage, adjacent well data analysis, ECD analysis and drilling time effect analysis through data analysis, so as to reduce the hydration swelling effect of the target formation rock and prevent wellbore instability. The present disclosure is suitable for wellbore instability prediction.

The invention belongs to the technical field of petrochemical engineering, and provides a deepwater superficial portion hydrate-containing stratum borehole stabilizer and a preparation method and application thereof. The deepwater superficial portion hydrate-containing stratum borehole stabilizer comprises a copolymer of a vinyl lactam monomer, acryloyl dopamine and a derivative of the acryloyl dopamine; the preparation method comprises the following steps: dissolving dopamine and a derivative thereof in a solvent, adjusting to be alkaline, adding an acrylic acid derivative with an acrylic acid or methacrylic acid group, reacting, dissolving the obtained acryloyl dopamine in a solution, mixing and dissolving with a vinyl lactam monomer and an initiator, and carrying out copolymerization reaction. After being added into a drilling fluid, the deepwater shallow hydrate-containing formation well wall stabilizer disclosed by the invention can play a multi-functional role, not only can improve the cementing property between hydrates and mineral particles and between mineral particles in a formation and improve the pressure-bearing strength of the formation, but also can inhibit the decomposition of the hydrates in the formation and the reduction of the strength of the formation, so that the drilling fluid can be well protected. And the well wall instability risk is reduced.

The present invention relates to the technical field of petroleum drilling. Disclosed are a plugging agent, and an oil-based drilling fluid and a use thereof. The plugging agent provided by the present invention has a multi-scale broad-spectrum strong plugging effect on formation micro-fractures, and the addition of the plugging agent into the oil-based drilling fluid can effectively solve the problem of wellbore instability and improve the safety of deep oil and gas exploration.

The invention provides a rock debris image data processing method and device, electronic equipment and a storage medium. The method comprises the following steps: acquiring rock debris image data and carrying out image segmentation processing to obtain rock debris classification data and a mask pattern; calculating the mask pattern to obtain rock debris particle size distribution data; performing shape analysis processing according to the rock debris particle size distribution data to obtain rock debris shape characteristic data; performing rock debris contour calculation on the mask pattern to obtain shape category data; performing visualization processing on the rock debris particle size distribution data to obtain a rock debris particle size distribution diagram, and performing rock debris particle block length ratio distribution diagram on the rock debris shape characteristic data; and performing visualization on the shape category data of the rock debris particle blocks to judge the instability condition of the well wall of the current drilling well. The efficiency and objectivity of rock debris classification and particle size calculation are remarkably improved through automatic images; comprehensive quantification of physical attributes of the rock debris is realized based on particle size and shape conjoint analysis, one-sidedness of a traditional method is avoided, and analysis precision and classification accuracy are effectively improved.

This invention relates to the field of drilling fluid treatment agents, and discloses a formulation with reduced filtration loss properties, its preparation method, and its application. The method includes: (1) mixing an organic solvent, an oil-phase matrix material, and an organic hydrophilic modifier to carry out a first modification reaction, wherein the oil-phase matrix material is selected from asphalt and / or resin; (2) adding graphene material to the system obtained in step (1) to carry out a second modification reaction. The formulation prepared by this method can not only quickly form an oil film on the wellbore to seal cracks, but can also be widely used in well sections prone to wellbore instability at 60-120℃, while also effectively improving the lubrication performance of drilling fluids.

The invention relates to the technical field of oil reservoir engineering, in particular to a stratum well wall stability evaluation method and device based on a mineral logging technology, and the method comprises the steps that the volume content of water-sensitive minerals in a stratum mudstone sample to be evaluated is obtained; determining the water absorption rate of each water-sensitive mineral; according to the volume content and the water absorption rate of the water-sensitive mineral, calculating to obtain the plastic water-sensitive strength of the mudstone mineral; and evaluating the formation well wall stability based on the mudstone mineral plasticity water sensitivity. On the basis of the mineral water sensitivity mechanism, the X diffraction mineral logging technology is combined with the well logging diameter curve, the water-sensitive stratum well wall instability level standard is established, the well logging diameter is used for verification, the reliability is high, and the method has the advantages of being capable of obtaining data while drilling in time, high in efficiency and high in field applicability and is suitable for shale and well drilling. And the method can also be expanded to other water-sensitive compact sand shale stratums, and is wide in application range.

The invention relates to the technical field of oil exploration, and discloses a casing liquid column pressure automatic balancing device which comprises an upper connector, a lower connector and a pressure balancing device. The outer sleeve is arranged outside the upper joint; the first shear pin is arranged on the inner side of the upper connector. When the whole device is tripped into a well, the internal and external pressure difference can be balanced, so that the whole device can be prevented from being extruded and damaged by the liquid column pressure difference generated due to untimely grouting, the labor intensity of workers can be reduced, a large amount of energy consumption for casing running pump starting grouting is saved, and the problem that the grouting pipeline is not firmly fixed and cannot be damaged is solved. And manual grouting at a well mouth is not needed, the potential safety hazard in the grouting process is reduced, the casing running speed is improved by more than 30%, the time is saved, the time efficiency is improved, air is prevented from being pressed into a well in the grouting process, and the well wall instability and well control risk caused by the pressure of a liquid column in the well are reduced.

The present application belongs to the technical field of oil and gas drilling engineering, and particularly relates to a polymer-coated inhibitor for strong inhibition drilling fluid and a preparation method thereof; the inhibitor is prepared by aqueous solution polymerization of acrylamide, acrylamidomethylpropane sulfonic acid, dimethyldiallylammonium chloride, vinyltrimethoxysilane and two novel inorganic modified compounds. The two inorganic modified compounds are a titanate intercalated magnesium aluminum tin silicate nanocomposite and a polyoxometalate grafted rare earth doped cerium dioxide nanorod, respectively. The former is prepared by coprecipitation and intercalation reaction, and the latter is prepared by hydrothermal synthesis and graft modification. The present application significantly improves the hydration inhibition capacity for shale, and can still maintain stable coating effect in high temperature and high salt environment, effectively solving the problem of wellbore instability. The preparation method is simple in process, the raw materials are all commercially available, and is suitable for industrial production, and has a broad application prospect in the field of water-based drilling fluid.

The invention discloses a fractured stratum modeling method for establishing a cluster template through three-dimensional scanning, which comprises the following steps: step 1, generating a real rock contour through three-dimensional scanning of a real rock sample, and establishing a basic flexible cluster template; 2, establishing a discrete element parameter calibration model, and simulating to obtain various mechanical parameters of the rock sample; step 3, establishing a real fractured stratum model; and 4, extracting a crack network structure by utilizing the well wall instability model in discrete element simulation, and further controlling the well wall instability phenomenon influenced by the well wall. According to the method, the contour of the rock block is obtained through three-dimensional scanning, the stratum model is constructed through the basic principle of the discrete element method, the cementation characteristic of the rock is restored, fracture of the rock block is simulated through Cluster, the particle crushing effect is reflected, namely, a more accurate crushed stratum well wall model is established, and the model is applied to the field of well wall construction. And the evaluation of the instability characteristics under the conditions of different fractured stratums, different fracture development degrees and the like can be realized.

The invention discloses a borehole wall stability analysis and risk evaluation method based on a quasi Monte Carlo method, and relates to the technical field of petroleum and natural gas drilling, and the method comprises the following steps: carrying out data cleaning and preprocessing on multi-source parameters, and carrying out parameter distribution modeling to obtain a multi-parameter joint probability distribution model; a quasi-Monte Carlo sampling method is utilized to obtain large-scale parameter combination samples with uniform sample coverage, and well wall stress, collapse conditions and fracture conditions are calculated to obtain collapse coefficients and fracture coefficients under each sample; performing variance decomposition according to a corresponding relation between each input parameter and a borehole wall instability result, identifying key control factors, constructing a training sample set, and training the long-short-term memory neural network model; and inputting related parameters obtained in an actual drilling process into the trained long-short-term memory neural network model to obtain a borehole wall stability result. By implementing the method provided by the invention, the accuracy and reliability of borehole wall stability analysis and risk prediction can be improved.

Aspects of the disclosure provide a method of mitigating liquid instability in controlled intra-well cross-flow between two, or more, zones accessed by a well. One or more embodiments define new functionalities necessary for dynamic multiphase flow (MPF) simulation to model, mitigate and control liquid instability observed in a well.

The present application relates to the technical field of oil reservoir engineering, and is a formation borehole wall stability evaluation method and device based on mineral logging technology, which comprises the following steps: obtaining the volume content of water-sensitive minerals in a mudstone sample of a formation to be evaluated; determining the water absorption rate of each water-sensitive mineral; calculating the plastic water-sensitive strength of the mudstone mineral based on the volume content and water absorption rate of the water-sensitive mineral; and evaluating the formation borehole wall stability based on the plastic water-sensitive strength of the mudstone mineral. The present application is based on the water sensitivity mechanism of minerals, combines X-ray diffraction mineral logging technology with well diameter curves, establishes a wellbore instability grade standard for water-sensitive formations, and is verified by well diameter logging, which is highly reliable, has the characteristics of timely and efficient data acquisition while drilling, and is highly applicable in the field. The present application is not only suitable for mud shale, but also can be extended to other water-sensitive tight sand-shale formations, and has a wide application range.

The invention discloses a borehole wall collapse pressure analysis method and device based on mudstone hydration. Comprising the steps that a mudstone well wall is regarded as a semi-permeable membrane, chemical potential difference is introduced, and a drilling fluid invasion physical model and a multi-field coupling equation under the drilling fluid invasion mudstone multi-field coupling condition are established under the solute diffusion condition; based on the assumed condition of drilling fluid invading mudstone, a well circumference stress calculation model under the multi-field coupling condition and a hydration mechanical stress balance equation, obtaining an all-directional stress expression under the hydration effect and boundary conditions of well wall instability calculation of the drilling fluid invading physical model, and obtaining stratum well circumference stress under the hydration effect; the change rule of rock mechanical parameters along with the formation water content is analyzed, a borehole wall collapse pressure model after mudstone hydration is established based on linear elastic hypothesis of the mudstone borehole wall and superposition of formation well circumferential stress, and the well circumferential borehole wall collapse pressure after mudstone hydration is solved in combination with actual drilling data. The method can be used for reasonably predicting the borehole wall collapse pressure of a mudstone-containing interlayer or sand mudstone.

The invention discloses a method for calculating the well wall falling block stacking height in the open hole well production process. The method comprises the steps that a reservoir rock mechanics parameter profile and a reservoir geomechanics parameter profile are calculated through a rock core mechanics experiment and field data; a true triaxial well wall instability experiment is carried out, well wall falling blocks are collected, and the natural stacking density of the well wall falling blocks is calculated; simulating a well wall instability process by a numerical simulation method, and drawing a well wall instability range chart; performing two-dimensional interpolation on the well wall instability range chart to obtain the well wall instability range of the whole well section of the open hole well, and calculating the total mass of well wall falling blocks through integration; and calculating the natural accumulation height of the falling blocks on the well wall. According to the method, the collapse instability range and the falling block stacking height under different production pressure differences can be calculated, and a theoretical basis is provided for design of the production pressure differences in different production stages.

The invention discloses a fracture and hole development type stratum borehole wall collapse instability prediction method, and relates to the field of petroleum and natural gas exploration and development, and the method is characterized in that firstly, according to a target stratum cylinder complete rock sample compressive strength experiment, a rock stress-strain curve, compressive strength and a material parameter m are obtained; further, rock mesomechanics parameters are determined according to a complete rock biaxial compressive strength test, and model parameters a and b and a hole index weight parameter B are obtained through fitting according to a crack and hole development type stratum rock strength criterion; then, interpretation and analysis are conducted according to target stratum imaging logging data, and the fracture development density Qf and the hole development density Qd of the predicted well section are obtained; and finally, in combination with the well periphery stress distribution model, calculating to obtain the bottom hole pressure of collapse and instability of the well wall of the crack and hole development type stratum. According to the method, the actual structural characteristics of the crack and hole development type stratum are fully considered, and the rock strength of the stratum and the prediction precision of the stratum well wall instability are remarkably improved.

The invention provides an integrated preparation method of microwave-assisted deep-eutectic solvent extraction-in-situ carboxymethylation modified cellulose, the modified cellulose and application. The preparation method comprises the following steps: (1) mixing choline chloride, urea and a modifier sodium chloroacetate, heating and stirring to form a uniform transparent liquid, and cooling to room temperature to obtain a deep eutectic solvent ternary system; (2) adding a biomass raw material into the eutectic solvent ternary system, and carrying out microwave treatment; and precipitating, centrifuging, washing and drying the obtained reaction liquid to obtain the modified cellulose. According to the method, raw material pretreatment, cellulose extraction and carboxymethylation reaction are integrated in a single reaction system, the technological process is remarkably simplified, the production cost is reduced, meanwhile, the product performance and environmental friendliness are improved, excellent performance is shown in the fields of oil field drilling fluid and the like, and the well wall instability risk is reduced.

The present application relates to a kind of polar permafrost cooling drilling device, i.e.method, to the problem of polar environment due to drill bit friction heat generation, temperature change in well causes wellbore instability deformation, rock sample thermal metamorphism etc., provide a kind of cooling drilling device and method.The present application is to maintain the function of low temperature foam drilling fluid circulation in low temperature environment in well, the drilling device provided has air sandwich and hole slot structure, realize the circulation of low temperature foam drilling fluid in the inside of drilling sampler, play the cooling effect, and avoid contact wellbore.This device can maintain wellbore stability, protect rock sample in polar permafrost environment compared with conventional drilling device.

The present application relates to the technical field of oil exploration, and discloses a casing liquid column pressure automatic balancing device, which comprises an upper joint for connecting a pipe column, an outer sleeve arranged outside the upper joint, and a first shear pin arranged inside the upper joint. When the device is lowered into a well, the device can balance the internal and external pressure difference, so that the device can be prevented from being squeezed and damaged by the liquid column pressure difference caused by untimely grouting, the labor intensity of workers can be reduced, a large amount of energy consumption for casing lowering and pump grouting can be saved, accidents caused by the unfirm fixing of grouting pipelines, such as splashing and dancing of the grouting pipelines, can be avoided, manual grouting at the wellhead is not needed, the safety hidden danger in the grouting process is reduced, the casing lowering speed is increased by more than 30%, time is saved, time efficiency is improved, air is prevented from being pressed into the well during the grouting process, wellbore instability and well control risks caused by the liquid column pressure in the well are reduced.

The utility model discloses a tool for drilling a well first and then inversely reaming in one-time well descending, and belongs to the technical field of oil and gas drilling, oil and gas exploitation and mining. The tool comprises a reverse reamer and a drill bit, wherein the reverse reamer comprises a tool arm, a supporting rod, a sliding rod, a sliding block and a flexible wear-resistant waterproof baffle. The supporting rod supports the unfolded cutter arm, the sliding block slides up and down along the sliding rod, and an outer locking mechanism is arranged in the sliding block and used for achieving locking and unlocking of the sliding block at the lower locking position and the upper locking position of the sliding rod; the flexible wear-resistant waterproof baffle is mounted between the two adjacent cutter arms; according to the one-time well descending first drilling and then reverse reaming tool, one-time well descending firstly uses the drill bit to drill a guide well with the small diameter, then the expanded reverse reaming device is used for reverse reaming, large drilling pressure, torque and displacement are not needed in the whole process, drilling cuttings always go upwards through an annulus with the small diameter, the well drilling efficiency can be improved, the cuttings carrying effect of drilling fluid can be improved, and the drilling efficiency is improved. The shaft bareness time is shortened, and the shaft instability risk is reduced.