2293 results about "Drilling fluid" patented technology

The invention discloses a radioactive measurement data processing method for improving uranium exploration efficiency. The method comprises the following steps: standardized data acquisition: integrating a multi-parameter module, carrying out time-space synchronous acquisition of geological geophysical environment parameters, standardizing protocol alignment data, and supporting three-dimensional modeling; a three-dimensional coupling model is used for processing interference in a sub-module mode, LiDAR-DEM is used for correcting gamma attenuation in the terrain, an optical fiber thermopermeability instrument is used for correcting daughter errors in the hydrology, signal attenuation of a borehole is compensated through a drilling fluid chart, and a space-time continuous interference field is formed; performing dynamic equilibrium coefficient inversion: constructing equilibrium coefficient isoparametric mapping, and inputting rock core, logging and geochemical data into a random forest model; the transfer learning is trained by using historical data, and dynamic inversion and updating of a new area are carried out; intelligent data processing three-dimensional visualization: self-adaptive denoising and spectral shape matching reinforcement abnormity are carried out; constructing a three-dimensional model, and carrying out transfer learning to optimize the precision; the WebGL platform integrates multi-parameter display, virtual drilling functions and high-dimensional data intuitive interpretation.

The invention discloses a nano blocking agent for drilling fluid and a preparation method thereof, and belongs to the technical field of blocking agents, the nano blocking agent for drilling fluid is prepared by reaction of a core layer blocking agent and a shell layer blocking agent, the core layer blocking agent is prepared by reacting nano silicon dioxide, gamma-methacryloxypropyltrimethoxysilane and a first part of vinylphosphonic acid, and has secondary blocking capability; and the shell blocking agent is prepared by reacting a second part of vinyl phosphonic acid, styrene and 2-dodecene-1-yl succinic anhydride, and has the characteristic of flexibility. The nano plugging agent has rigid supporting and flexible deformation capabilities, and the high-temperature stability and compressive strength of a plugging layer are remarkably improved. The chemical binding force of the plugging agent and the rock is enhanced; the hydrolysable methoxyl reserved in the core layer provides a secondary plugging function, and the plugging validity period is prolonged. The invention relates to a preparation method of a nano blocking agent for drilling fluid, which is used for preparing the nano blocking agent for drilling fluid.

The invention provides an underwater ultrasonic Doppler real-time analysis method and device based on a digital transducer, and relates to the technical field of data analys.The method comprises the steps that 1, multiple beams of directional ultrasonic waves are emitted into drilling fluid through a digital transducer array on the outer wall of a marine riser, echo signals reflected by gas-liquid two-phase flow are received, and the digital transducer array is used for receiving the echo signals; performing real-time digital conversion on the echo signal to generate an original digital signal containing phase and amplitude information; 2, Doppler frequency shift feature extraction is conducted on the original digital signals, and the real-time movement speed and direction of bubbles in the drilling fluid are determined by calculating the frequency deviation of reflected ultrasonic waves and transmitted ultrasonic waves. Through the digital transducer array and the ultrasonic Doppler technology, accurate measurement of motion parameters of bubbles in drilling fluid, real-time calculation of local gas content and early warning and grading response of gas cut are achieved, and the safety and the intelligent level of drilling operation are improved.

The invention discloses a drilling trajectory real-time dynamic tracking control method and system based on deep learning, and relates to the technical field of petroleum drilling, and the method comprises the steps: generating well trajectory control parameters according to the basic information of a well and preset well trajectory data; setting an optimal drilling fluid performance parameter corresponding to the current working condition according to the stratum environment where the drilling tool is located; deep learning is conducted on the well track control parameters and the optimal drilling fluid performance parameters through the correlation model, a drilling parameter setting scheme is generated, and an underground drilling tool is controlled to conduct drilling; comparing the drilling data with data in the drilling parameter setting scheme, and determining deviation in the drilling data; and determining a corresponding fault mode, and determining a corresponding solution from the solution library to correct the drilling parameter setting scheme. According to the method, deep learning is carried out on geological conditions and historical data, the well trajectory control model and other models are constructed, the model can be continuously updated and optimized along with data accumulation, and the drilling trajectory tracking and control precision is continuously improved.

The invention provides a salt-responsive temperature-resistant salt-resistant water-based drilling fluid tackifying filtrate reducer as well as a preparation method and application thereof, and belongs to the technical field of drilling. The tackifying filtrate reducer is prepared from the following raw materials in parts by mass: 30 to 50 parts of 1-(2-carboxyethyl)-2-vinylpyridine, 20 to 40 parts of (3-(methacrylamido) propyl) dimethyl (3-thiopropyl) ammonium hydroxide inner salt, 35 to 55 parts of N, N-dimethylacrylamide, 10 to 25 parts of 4-vinylpyridine, 300 to 500 parts of water and 1 to 5 parts of an initiator. According to the filtrate reducer, cations and anions are concentrated on one monomer molecule, so that the synthesized product contains the cations and the anions with the same charge number, has good adsorption capacity and salt response characteristics, is compatible with salt essentially, can effectively resist high temperature and high salt, and can be recycled. And the viscosity-increasing and filtrate-reducing agent has good viscosity-increasing and filtrate-reducing effects on the drilling fluid.

A milling bit valve is disclosed for improved debris collection within a wellbore. The check valve can be part of a debris removal tool that includes a motor, pump, gearbox, bailer, milling bit, check valve, and rotational shafts. In an example, on its uphole end, the milling bit can be coupled with the check valve. On its downhole end, the milling bit can be configured for debris removal with cutting edges. The downhole end can also include openings that provide access to an internal cavity of the milling bit. The internal cavity can extend the entire length of the milling bit. This allows the pump to pull drilling fluid into the bailers through the milling bit and check valve. As a result, the debris removal tool can simultaneously remove obstructions in a wellbore and collect debris from the obstruction removal.

Shown and described herein is a choke assembly for use with a downhole drill string. The choke assembly may include a rotating choke carrier, a stationary seat disposed on the rotating choke carrier and a rotating choke positioned adjacent to the stationary seat to create a seal surface. The choke assembly may further comprise a biasing mechanism applying a biasing force to press the rotating choke against the stationary seat and a flow port within the stationary seat which controls drilling fluid to allow some drilling fluid to become a bypass fluid and pass through the stationary seat.

The utility model provides an efficient drill bit for a mine drilling machine, which belongs to the technical field of drill bits and comprises a drill rod and a drill bit body arranged on the drill rod, a flange ring is mounted on the outer wall of one end of the drill rod, and a fixing seat is arranged at one end of the drill rod. According to the utility model, the crushing teeth arranged on the drill bit body are matched with the buffer springs, so that the positions of the crushing teeth can be effectively and automatically adjusted according to the hardness of external rocks and the drilling pressure, thereby reducing greater abrasion of the crushing teeth caused by hard rocks or abnormal loads, prolonging the service life of the drill bit, and improving the drilling efficiency at the same time; the spiral blade arranged outside the drill rod close to one end of the mounting seat continuously lifts the waste drilling fluid between the drill rod and the well wall in the process of synchronously rotating along with the drill rod, so that rock debris can be quickly and effectively removed from a drill hole, and the rock debris is prevented from being accumulated at the bottom of a drill bit to reduce the rock breaking efficiency; meanwhile, friction between the drill bit and rock is reduced, abrasion of the drill bit is reduced, and the drilling effect of the drill bit is improved.

The invention belongs to the technical field of drilling fluid, and particularly relates to a free radical polymerization water-based drilling fluid composition and a preparation method thereof. The invention relates to a core-shell composite particle-containing water reducer which comprises deionized water, salts (NaCl / KCl), alkalis (Na2CO3 and NaOH), barium sulfate and core-shell composite particles X. The particle is composed of a silicon dioxide core and a polymer shell layer, and the shell layer is formed by free radical copolymerization of acrylamide, 2-acrylamido-2-methylpropanesulfonic acid and acrylic acid and is covalently connected with the core through silanization treatment. Under the conditions of high salinity, strong alkali and high solid phase weighting, the drilling fluid simultaneously realizes the following effects: (1) high-density bearing and low-viscosity pumpability are realized; (2) compact plugging and water loss reduction and low formation damage flowback can be realized; and (3) stable rheology rock carrying, lubrication and friction resistance reduction. The problem that three aspects of performance are difficult to consider in the prior art is solved, and the drilling fluid is suitable for drilling of deep wells, ultra-deep wells and complex stratums and has remarkable industrial application value.

The invention relates to a preparation method and application of high-temperature-resistant organic modified bentonite. According to the method, three organic modifiers of long-chain quaternary ammonium salt, amide and a silane coupling agent are compounded to modify bentonite, and the problem that a single modifier is easy to decompose at high temperature is solved through the synergistic effect of physical intercalation, chemical crosslinking and interface bonding; and secondly, a three-dimensional stable structure is constructed by adding nano silicon dioxide and a composite modifier, so that the high temperature resistance and dispersion stability of the modified bentonite are further enhanced. According to the invention, the requirements of deep well and ultra-deep well drilling fluids on the temperature resistance and rheological property of the treating agent can be met, and the ultra-deep well drilling fluid which can tolerate the high temperature of 250-300 DEG C, and is low in filter loss and good in dispersion stability can be obtained.

The invention provides composite anionic cellulose ether as well as a preparation method and application thereof. The composite anionic cellulose ether is prepared by etherifying alkalized cellulose through an etherifying agent A and an etherifying agent B in sequence, the etherifying agent A is selected from water-soluble halogenated alkyl sulfonic acid and / or water-soluble halogenated alkyl sulfonate; the etherifying agent B is selected from water-soluble halogenated alkyl carboxylic acid and / or water-soluble halogenated alkyl carboxylate. According to the composite anionic cellulose ether, a sulfonic acid group and a carboxylic acid group are sequentially introduced, so that the composite anionic cellulose ether has relatively high temperature resistance and salt and calcium resistance; the compound can be used as a filtrate reducer for the drilling fluid, can effectively control the filter loss of the drilling fluid, and can improve the salt pollution resistance of the drilling fluid, especially the calcium and magnesium ion pollution resistance.

The invention discloses an ultra-deep well drilling wellbore pressure inversion correction method, and aims to improve pressure prediction precision and well control safety in an ultra-deep well drilling process. The method mainly comprises the following two parts: firstly, establishing a wellbore pressure calculation model, fully considering the change of drilling fluid density along with temperature and pressure based on a mass and momentum conservation equation in a drill rod and an annulus, performing discrete solution on the established control equation by adopting a finite difference method, and performing iterative calculation from a well bottom to a well mouth and from the well mouth to the well bottom, so as to obtain a well pressure calculation model; and acquiring pressure and physical property parameters of each node. Secondly, on the basis of model output, a friction correction factor is introduced, a nonlinear state space model is constructed, an unscented Kalman filter (UKF) algorithm is used for conducting dynamic estimation on the friction correction factor, and online self-adaptive correction on the wellbore pressure model is achieved; according to the method, the accuracy of wellbore pressure calculation is effectively improved, and reliable technical support is provided for ultra-deep well operation.

Disclosed are a device and method for rapidly regulating downhole pressure after a kick in deepwater shallow open-circuit drilling. The device includes a real-time monitoring device and a real-time regulation device. Aiming at deepwater shallow open-circuit drilling characteristics, the present disclosure proposes that a drilling fluid return condition at a seabed is monitored through a subsea remote operated vehicle (ROV); based on this data, whether gas influx occurs in a downhole or not and changes of the gas influx rate and the formation pressure after the gas influx are analyzed in real time, and then real-time guidance is provided for the design of key parameters such as well killing fluid displacement and density, and the well killing fluid displacement and density are regulated in real time, to achieve rapid regulation of the downhole pressure after gas influx of deepwater shallow open-circuit drilling.

The invention discloses a jet fluid pushing type self-guiding drill bit which comprises a drill bit assembly, a drilling part, a gauge protection part and a drill body part which are sequentially connected, a blade and a drilling nozzle are arranged on the drilling part, a plurality of pushing nozzle rows are arranged on the gauge protection part at intervals in the circumferential direction, each pushing nozzle row comprises at least one pushing nozzle, and the drilling body part is provided with a plurality of pushing nozzles; a drilling fluid flow channel communicated with the drilling nozzle and the pushing nozzle is formed in the drill bit assembly; the rotary inner cylinder is arranged in the drilling fluid flow channel of the gauge protection part, an overflowing hole row is formed in the side wall of the rotary inner cylinder, and the overflowing hole row comprises at least one overflowing hole; the measurement and control assembly is arranged on the drill body part in a sealed mode, and the measurement and control assembly comprises a near-bit measurement module, a data processing module, a regulation and control module and a power module; and the regulation and control module can control the rotary inner cylinder to rotate to a target position relative to the drill bit assembly based on real-time parameters obtained by the near-bit measurement module, so that the drill bit assembly can drill and deflect in the target drilling direction under the counter-acting force of the jet flow of the jet flow liquid pushing the well wall.

The invention provides a tool applied to the field of petroleum drilling, and particularly relates to an underground non-circular gear intelligent impact tool which comprises a power module, an axial impact module and a circumferential impact module, the power module enables drilling fluid to impact a turbine in a directional mode through a drainage disc, hydraulic energy is converted into mechanical energy, and the mechanical energy is transmitted to the axial impact module. The power is transmitted to the axial impact module and the circumferential impact module, the axial impact module lifts a rack punch hammer to compress a spring through meshing of an incomplete gear and the rack punch hammer, and when the incomplete gear is disengaged from the rack punch hammer, the spring releases energy to generate axial impact downwards. The circumferential impact module is composed of two groups of incomplete gears and racks which are arranged in an up-down 90-degree staggered mode, the rack punch hammer compresses a spring through meshing of the incomplete gears and the rack punch hammer, and the spring is released to generate circumferential impact when the incomplete gears and the rack punch hammer are disengaged. Periodic impact can be achieved, the mechanical rock breaking efficiency is effectively improved, and the stick-slip phenomenon at the drill bit is reduced.

The invention provides a 180 DEG C-resistant microcapsule type cementing wall-fixing agent for water-based drilling fluid as well as a preparation method and application thereof, and belongs to the technical field of drilling. The preparation method of the wall fixing agent comprises the following steps: (1) respectively adding the macromolecular hydrophilic colloid and the emulsifier into deionized water, and stirring until the macromolecular hydrophilic colloid and the emulsifier are completely dissolved to obtain a water phase; (2) adding phenolic resin, the MUF prepolymer solution and nano SiO2 into an organic solvent under a stirring condition, and uniformly stirring to obtain an oil phase; (3) adding the oil phase obtained in the step (2) into the water phase obtained in the step (1), and carrying out shear emulsification to obtain an oil-in-water emulsion; and evaporating to remove the organic solvent in the system, filtering, washing, and drying to obtain the product. Under the multi-element synergistic effect of hydrogen bonds or coordinate bonds, Van der Waals force and the like, the microcapsule type cementing wall-fixing agent can accelerate the interface to form a compact cemented network structure, the cementing strength of rock particles is remarkably improved, and the purpose of strengthening the stability of a well wall is achieved.

The invention provides a mining roller bit, and belongs to the technical field of drilling equipment. The invention provides a mining roller bit. The mining roller bit comprises a bit leg, a roller, a connector and a scrap throwing assembly. The tooth palm is provided with a plurality of tooth claws, and shaft necks are arranged on the tooth claws; the roller cone is rotationally mounted on the shaft neck, and a mounting position is arranged on the roller cone; the connector is arranged on the bit leg; the scrap throwing assembly is mounted on the mounting position; the scrap throwing assembly comprises a fixed ring body, a force transmission part, a telescopic part and a scrap throwing part; the fixed ring body is mounted on the mounting position, a plurality of through groove groups are formed in the fixed ring body, each through groove group comprises a first hole groove, a second hole groove and a connecting groove, and the force transmission part is arranged in the connecting groove; the telescopic part is arranged in the first hole groove; the scrap throwing part is arranged in the second hole groove; in the rotating process of the cone, the scrap throwing part can be matched with drilling fluid by rotating, rock debris and slurry adhered between the cutting edges are scattered, blockage between the cutting edges is avoided, and therefore the cutting efficiency in the drilling process is improved.

The invention belongs to the field of oilfield chemistry, and discloses development and a method of a gel breaker for recycling drilling fluid, and the preparation method comprises the following steps: (1) contacting chitosan with a modifier under an alkaline condition for chemical modification to obtain O-carboxymethyl chitosan; and (2) carrying out radical polymerization on the obtained O-carboxymethyl chitosan and a quaternary ammonium salt monomer in an acid environment under the action of an initiator to obtain the gel breaker.

The invention discloses an environment-friendly recycling device for oil-based drilling fluid, and relates to the technical field of petroleum drilling. The solid-liquid separation mechanism is located in one end of the shell and used for filtering solid impurities in the drilling fluid; the control panel is connected with the shell and is used for integrally controlling the equipment; the solid waste is ingeniously used as a filtering medium, solid impurities in the drilling fluid are effectively removed, the separation effect is further improved through the stacking and filtering effects of the solid waste, the solid waste is gradually stacked in the filtering process to form a multi-layer filtering barrier, particle impurities in the drilling fluid can be more thoroughly intercepted, and the filtering effect is improved. By means of the design, the limitation of a single filtering medium in a traditional filtering mode is avoided, the replacement frequency and the maintenance cost of the filtering medium are reduced, and the economical efficiency and the environmental protection property of the whole treatment process are further improved.

The invention provides a mussel bionic well wall thermal insulation material for drilling fluid as well as a preparation method and application of the mussel bionic well wall thermal insulation material. The mussel bionic well wall thermal insulation material for the drilling fluid is prepared from a viscous polymer, a structure reinforcing material, a nano thermal insulation hollow sphere material and a coating material, and has the characteristics of low heat conductivity coefficient, high strength, slow release of viscosity and high adhesion strength; when the thermal insulation material reaches a high-temperature stratum, the outermost coating layer is gradually broken under the action of high-temperature and high-speed shearing force, the inner viscous polymer-structure reinforcing material-nanometer thermal insulation hollow sphere material composite material is slowly released, the viscous polymer and well wall rock are combined through chemical bonds, and the thermal insulation performance of the well wall is improved. The composite material is tightly adsorbed on the well wall to form a stable heat insulation barrier, the problem that a traditional material falls off due to insufficient adsorption force is solved, and the heat insulation effect in the high-temperature environment is remarkably improved.

The invention discloses a while-drilling barrel rock debris and gas logging sample collecting device. The while-drilling barrel rock debris and gas logging sample collecting device comprises a liquid-sand separation system, a rock debris collecting system and a gas logging sample collecting system. The liquid-sand separation system is used for separating while-drilling well drilling fluid into drilling fluid liquid and rock debris and respectively conveying the drilling fluid liquid and the rock debris to the gas logging sample collection system and the rock debris collection system, and rock debris samples are collected through the rock debris collection system; the gas logging sample collection system comprises a quantitative metering mechanism and a degassing mechanism, and the quantitative metering mechanism quantitatively conveys the drilling fluid to the degassing mechanism; the degassing mechanism comprises a heating mechanism and a vacuum stirring degassing mechanism, and the drilling fluid is degassed through the heating mechanism and the vacuum stirring degassing mechanism to obtain the gas logging sample; the problems that an electric degasser cannot conduct quantitative degassing, oil gas in the C6-C8 range in mud cannot be removed, and the timeliness of manual rock debris collection is poor are effectively solved.

A method may include receiving real-time data relating to drilling fluid for drilling operations that utilize a drilling fluid system that includes tanks and pumps, where the drilling operations include operations that pump the drilling fluid to a drill bit on a drillstring that rotates to extend a borehole in a formation, and where the drilling fluid flows to an annulus between the drillstring and the formation to apply pressure to the formation; detecting a tank state from a group of tank states based at least in part on the real-time data, where the group of tank states includes tank states defined with respect to one or more operations of the pumps; and detecting a change in tank volume, based at least in part on the tank state, as an indicator of an undesirable interaction between the drilling fluid and the formation.

The invention discloses a simulation experiment device and method for casing drilling, and relates to an experiment device and method for simulating the smearing effect of casing drilling, and the device comprises a simulation assembly and a manifold assembly. The simulation assembly comprises an experiment kettle, a simulation piece and a casing pipe nipple, and an annular gap is defined between the simulation piece and the casing pipe nipple. The manifold assembly and the annular gap form a flow loop of drilling fluid. The manifold assembly comprises a liquid storage tank, a pump body and a material storage tank, and the pump body and the material storage tank are arranged between the liquid storage tank and the inlet end of the annular gap. Wherein the storage tank can enable the rock debris to enter the annular gap along with drilling fluid pumped by the pump body, and the simulation assembly can enable the casing pipe nipple to rotate at a preset rotating speed under a preset axial acting force under a preset experiment condition, so that the rock debris entering the annular gap forms a mud cake on the inner surface of the simulation piece. The experimental device can be used for analyzing influence factors of the smearing effect of casing drilling and guiding on-site construction of the casing drilling, so that the smearing effect of the casing drilling can play a more remarkable effect.

The invention provides a temperature-resistant and salt-resistant wall-fixing agent for a water-based drilling fluid for a myriameter deep well as well as a preparation method and application of the wall-fixing agent, and belongs to the technical field of drilling. The preparation method of the wall fixing agent comprises the following steps: adding acrylic acid into deionized water, adjusting the pH value of a system to 7.0, then sequentially adding N-hydroxymethyl acrylamide, N-[2-(3, 4-dihydroxyphenyl) ethyl]-2-acrylamide, an emulsifier, octadecyl vinyl ether and a complexing agent into the system, and shearing to obtain a monomer solution; adding an initiator into the monomer solution, and reacting; and after the reaction is completed, washing, drying and crushing to obtain the wall fixing agent. The wall fixing agent can resist the temperature of 200 DEG C, can resist the salt to be saturated, has strong adsorbability and high cohesion, and can effectively adsorb, block and bond micropores and micro cracks of rocks, so that the rocks are solidified, the well wall stability is effectively enhanced, drilling fluid leakage is prevented, and a technical guarantee is provided for safe and efficient drilling of deep wells.

The invention belongs to the technical field of drilling fluid processing, and particularly relates to a special silicate water-based drilling fluid for a coal-bed gas well as well as a processing method and a processing device of the special silicate water-based drilling fluid. The top end of the stirring tank is communicated with a first feeding hole and a second feeding hole, and the bottom end of the stirring tank is communicated with a discharging pipe; a rotating shaft is rotationally connected to the top surface of the inner wall of the stirring tank, and a sliding groove is formed in the bottom surface of the rotating shaft; a rotating shaft is driven by a first motor to rotate, and the rotating shaft drives a connecting shaft to rotate, so that fresh water and additives in a stirring tank are stirred and mixed by stirring blades, and a first screw rod can be driven by the first motor to positively and negatively rotate in a reciprocating manner in the mixing process; the first screw rod drives the connecting shaft to move up and down in the sliding groove, so that the stirring blades move up and down, the stirring blades stir and mix the water and the additive while moving, and the mixing efficiency and uniformity of the additive and the water are improved.

The invention discloses a high-temperature-resistant and high-pressure-resistant autonomous deep well pressure maintaining sampler, and belongs to the technical field of drilling engineering sampling. The sampler comprises an upper joint, a control outer pipe, an end cover, a valve body and a liquid storage chamber which are connected in sequence, an electromagnet is arranged on the outer side of the end cover; an electric control module is arranged in the control outer pipe; a valve element with a permanent magnet is arranged in the valve body in a sliding mode, the valve element is driven to move axially through non-contact electromagnetic force between the electromagnet and the permanent magnet, and opening and closing of the sampling flow channel are achieved. The bottom of the valve core is provided with a valve core inner channel communicated with the sampling flow channel and the liquid storage chamber and a one-way valve; a sampling inlet channel is formed in the joint of the end cover and the valve body. According to the invention, a pure mechanical sealing-based structure is adopted, so that the sealing reliability and the operation stability in a high-temperature and high-pressure environment of a deep well are remarkably improved, drilling fluid is not needed, and efficient and pressure-maintaining sampling of in-situ formation fluid is realized.

The application provides a temperature-resistant and salt-resistant wall stabilizer for a ten-thousand-meter deep well water-based drilling fluid and a preparation method and application thereof, and belongs to the technical field of drilling. The preparation method of the wall stabilizer comprises the following steps: acrylic acid is added into deionized water, the pH of the system is adjusted to 7.0, then N-hydroxymethyl acrylamide, N-[2-(3,4-dihydroxyphenyl)ethyl]-2-acrylamide, an emulsifier, octadecyl vinyl ether and a complexing agent are sequentially added into the system, shearing is performed, a monomer solution is obtained, an initiator is added into the monomer solution, and reaction is performed; after the reaction is completed, washing, drying and crushing are performed, and the wall stabilizer is obtained. The wall stabilizer has a temperature resistance of 200 DEG C and a salt resistance of saturation, has strong adsorption and high cohesion, can effectively adsorb, plug and cement micro-pores and micro-cracks of rocks, thereby consolidating the rocks, effectively enhancing the well wall stability, preventing drilling fluid leakage and providing technical support for safe and efficient drilling of deep wells.

The invention relates to a composite percussion drilling speed increasing tool, and belongs to the technical field of drilling tools. The reciprocating hammering unit comprises a hammer body and an impact hammer, the hammer body is axially and slidably connected into the sleeve, the impact hammer is rotatably connected into the hammer body, a reversing sleeve is rotatably connected into the impact hammer, a reversing cabin is arranged on the reversing sleeve, and a reversing runner hole is formed in the hammer body; the flow channel switch unit comprises a baffle ring arranged on the surface of the hammer body and a transmission mechanism connected between the sleeve and the baffle ring, and the transmission mechanism is used for converting axial motion of the baffle ring into rotary motion so as to open or close the reversing flow channel hole. When the drilling tool is lifted, the axial movement of the baffle ring can be converted into rotary movement, so that the baffle ring rotates relative to the hammer body while axially displacing along with the hammer body, a reversing flow channel hole is shielded, and high-pressure drilling fluid cannot flow into a reversing cabin, so that high-frequency composite impact is stopped, vibration and abrasion caused by idling are avoided, and the service life of the drilling tool is prolonged. And the service life and the safety of the tool are improved.

Provided in the present invention are a high-temperature-resistant filtrate reducer, a water-based drilling fluid and the use of the high-temperature-resistant filtrate reducer in drilling engineering in high-temperature subsurface environments. The filtrate reducer comprises carboxymethyl cellulose and a water-soluble polymer containing epoxy, and an open-loop coupling reaction of carboxyl and epoxy groups in high-temperature environments is utilized to induce in-situ self-crosslinking of carboxymethyl cellulose in high-temperature deep downhole environments, so that the filtrate loss reduction performance of the filtrate reducer at high temperatures is remarkably improved.

A system for pulsed power drilling a wellbore into a subsurface formation comprises a drill bit that includes at least one electrode coupled to a power source, the at least one electrode to periodically emit an electrical discharge based on electrical pulses received from the power source. The system comprises a first port to output a first type of drilling fluid having a different composition than a second type of drilling fluid to flow downhole for removal of cuttings, wherein the electrical discharge is to be transmitted through the first type of drilling fluid and through a rock of the subsurface formation, wherein an additive or a property of at least one of the first type of drilling fluid or the second type of drilling fluid reduces mixability between the first type of drilling fluid and the second type of drilling fluid.