41 results about "Deepwater drilling" patented technology

The invention relates to a preparation method and application of an inner-rigid outer-soft core-shell structure silicon dioxide blocking agent for marine drilling fluid, and belongs to the field of deepwater oil and gas drilling. N-vinyl-2-pyrrolidone, dimethyl diallyl ammonium chloride, acrylamide and 2-acrylamide-2-methylpropanesulfonic acid are polymerized and grafted on the surface of nano silicon dioxide to form the silicon dioxide blocking agent with a core-shell structure and a rigid inside and a soft outside; by means of rigid plugging of a nano material and deformation filling flexible plugging of a high-molecular polymer, shale micro-nano pores are efficiently plugged with rigid inside and flexible outside, so that the stability of a well wall is maintained, meanwhile, secondary generation of hydrates is effectively inhibited, and the safety and efficiency of deepwater drilling are improved; the plugging agent provided by the invention reduces the demand on a large number of thermodynamic inhibitors, not only saves the cost, but also has the characteristic of environmental protection.

The invention provides a deepwater drilling method for inhibiting bottom stratum erosion of a multi-wellhead suction pile and the suction pile. The drilling method comprises the steps that guide pipes and pre-inclined casing pipes are prefabricated and installed at a plurality of wellheads at the top of a pile cylinder to form the suction pile, the pre-inclined casing pipes and the guide pipes at the same wellhead are sequentially arranged in a sleeving mode from inside to outside, and the pre-inclined casing pipes and the guide pipes are arranged at the same wellhead in a sleeving mode from inside to outside; the shaft sleeve is coaxial with the wellhead; the suction pile is conveyed to a water entry position opposite to the drilling position; the suction pile is put down and penetrates into the set position of the stratum; a first well hole with the preset depth is drilled downwards in each pre-inclined casing pipe, and a first casing pipe is placed downwards in each first well hole; cement is injected into the first casing pipe for well cementation, so that the preset pressure intensity is achieved, and stratum erosion is restrained; and a second well hole with the preset depth is drilled downwards in the first casing pipe, a second casing pipe is placed downwards in the second well hole, well drilling is completed, erosion of the bottom stratum of the pile barrel can be restrained, and stage well drilling operation can be completed safely and efficiently.

The invention discloses a drilling tool for underwater installation and recovery of a top locking assembly and a construction method.The tool comprises a mandrel, an outer body, a release ring and a recovery ring, the outer body is in threaded connection with the mandrel through one corresponding step face, and the other step face of the mandrel is sleeved with the release ring in a threaded mode; a C-shaped recycling ring is arranged in the first containing groove, the recycling ring is bounced off or compressed through vertical movement of the release ring, and the recycling ring is clamped to the top locking assembly to recycle the top locking assembly when bounced off. The mandrel is provided with a first transmission block and a second transmission block which both protrude out of the mandrel, and the first transmission block and the second transmission block are correspondingly arranged in the grooves of the top locking assembly in a matched mode. The top locking assembly can be lowered, installed, adjusted in clearance and locked through one-time drilling, and at least one-time drilling is saved; and the underwater unlocking and recycling function of the top locking assembly is integrated, additional special tool allocation is reduced, tool allocation is optimized, the deepwater drilling operation cost is saved, and the operation efficiency is improved.

The invention belongs to the technical field of deepwater drilling, and discloses a deepwater drilling system and a deepwater drilling method. The deepwater drilling system comprises a drilling ship, a waterproof unit, a regulation and control device, a blowout prevention device and a drilling device. The upper end of the waterproof unit is connected with a drilling ship and provided with a first penetrating channel. The regulation and control device is arranged at the lower end of the waterproof unit and provided with a plurality of connecting channels. The connecting channel has an open state and a closed state, and in the open state, the first penetrating channel communicates with the outside through the connecting channel. And the blowout preventer is arranged at the wellhead and is connected with the waterproof unit. And the first penetrating channel can be communicated with a second penetrating channel of the blowout preventer. The drilling device is arranged on the drilling ship and penetrates through the first penetrating channel, the second penetrating channel and the well mouth. The well drilling device is provided with a conveying channel, and drilling fluid can be conveyed to the lower end of the well drilling device through the conveying channel. When the system is used for drilling operation, the pressure borne by a stratum at a wellhead can be effectively reduced, and stratum fracturing is avoided.

The present application relates to the technical fields of deepwater drilling and workover technology of offshore oil engineering, and particularly relates to a joint for emergency release of a deepwater light drilling and workover underwater riser and an operating method thereof. The emergency release joint comprises an upper joint body and a lower joint body which are mutually butted. A locking assembly composed of a clamp and a support ring is arranged on the periphery of the butt joint, and an electromagnetic drive assembly is correspondingly arranged. Upper and lower blowout preventer modules are arranged on both sides of the butt joint along the fluid passage in axial opposition. The electromagnetic drive assembly is used to drive the support ring to move between two working positions, so as to control the locking or releasing of the clamp on the butt joint. In operation, the upper and lower blowout preventer modules are first controlled to be closed, and then the mechanical locking is released to realize the release of the joint. After reconnection, the mechanical locking is restored and the fluid passage is opened. The scheme is suitable for emergency release and subsequent reconnection of the deepwater riser under abnormal working conditions.

The present invention discloses a subsea wellhead simulation test device and a test method for deep - water offshore drilling. The device includes: a kettle body, the chamber of which is used to fill with soil layers; earth pressure gauges, which are used to be distributed in the soil layers; a surface conductor, the bottom end of which is located in the soil layer and the top end is located above the soil layer; a subsea wellhead device, which is installed at the top end of the surface conductor; a riser, which is connected above the surface conductor through the subsea wellhead device; a tensioner, which is connected to the top end of the riser; a platform device, which is arranged on the tensioner; an experimental frame, which is erected around the kettle body; a push - pull motion device, which is used to simulate the marine environmental loads and the motion of the platform device; a height - adjusting mechanism, which is used to change the height position of the push - pull motion device; and a controller, which is electrically connected to the earth pressure gauges, the subsea wellhead device and the tensioner. The present invention can simulate the influence of the marine environmental loads on the subsea wellhead in deep water to reveal the variation law of the interaction between the deep - water surface conductor and the soil body.

The present application relates to a kind of pressure shell for riser monitoring and its fixing device, which mainly includes pressure shell, first fixed support, second fixed support, throat hoop steel band. Wherein the reliability of pressure shell is improved by triple sealing of pressure shell. The design of core plate fixed by screw through sleeve and lower bottom surface of sleeve, clamping snap ring is fixed by buckle, and secondary fixing is guaranteed, so that the monitoring error of pressure sealing shell will not be increased due to relative motion between structures during monitoring operation. First fixed support is disassembled with second fixed support by the contraction of internal spring of stop pin, which is simple in structure, easy to operate, and enhances the quick convenience of installation and disassembly. Throat hoop steel band passes through the V-shaped plate of second fixed support, and the support is fixed on the riser before being lowered, which improves the flexibility and versatility of device installation. The present application can be widely applied in pressure shell and its fixing device for deepwater drilling riser monitoring.

The invention belongs to the technical field of deepwater oil and gas field drilling gas cut monitoring, and particularly relates to a deepwater drilling gas cut monitoring method. According to the monitoring method, nonlinear dynamic characteristics of ultrasonic signals are extracted through multi-scale fuzzy divergence entropy, and a gas content value is obtained based on inversion of a support vector machine model subjected to sample training, so that quantitative monitoring and early warning of tiny changes of the gas content are realized; compared with an existing deepwater drilling gas cut monitoring method, the method has the remarkable advantages in the aspects of monitoring precision, dynamic response characteristics, noise interference resistance and the like, and accurate recognition and real-time quantitative monitoring of early weak gas cut signals can be achieved. A deepwater drilling gas cut monitoring method comprises the following steps that ultrasonic echo signals of gas-liquid two-phase flow are collected; extracting a multi-scale fuzzy divergence entropy value in the ultrasonic echo signal; and inputting a feature vector in the multi-scale fuzzy divergence entropy into the trained support vector machine classification model to obtain a gas content recognition result.

The application relates to a deep-water drilling chamber indoor vibration experiment device and an experiment method. The device comprises a derrick, a flexible drill string, a rigid drill string, a rock sample clamping mechanism, an air wave generator, a torque dynamometer and a sensor group. The actual marine environment is simulated through the air wave generator, and the dynamic characteristic parameters of the drill string system are collected through the torque dynamometer and the sensor, so that the problem that the actual marine environment load cannot be simulated, and the dynamic characteristic parameters of the drill string system cannot be accurately and comprehensively obtained in the prior art is solved.

This invention discloses an integrated logging-while-drilling (LOD) and measurement drill string assembly, relating to the field of oil and gas drilling engineering technology. It provides a series connection scheme for core protective drill string components, offering two switchable configurations: one with a mud motor and one without. Both configurations consist of an azimuth density neutron logging sub, a bidirectional communication power supply sub, an acoustic logging sub, a resistivity logging sub, an upper connecting sub, a flexible sub, a lower connecting sub, an azimuth gamma logging sub, and a steering actuator connected in series according to a fixed logic. The configuration with a mud motor only requires adding a mud motor at a designated location to complete the structural switch, without changing the series connection of the remaining subs. This assembly scheme is applicable to various drilling scenarios such as offshore exploration and development, deepwater drilling, complex directional wells, highly deviated wells, and horizontal wells. It enables integrated operations of geological steering, formation evaluation, and wellbore stability analysis during drilling, effectively improving drilling efficiency and reducing operational risks.

The present application belongs to the technical field of gas invasion monitoring of deepwater oil and gas field drilling, and particularly relates to a deepwater drilling gas invasion monitoring method. The monitoring method extracts the nonlinear dynamic characteristics of ultrasonic signals through multi-scale fuzzy divergence entropy, and obtains the gas holdup value based on the support vector machine model trained by samples, thereby realizing quantitative monitoring and early warning of the small change of gas holdup. Compared with the existing deepwater drilling gas invasion monitoring method, the present method has significant advantages in monitoring accuracy, dynamic response characteristics and anti-noise interference performance, and can realize accurate identification and real-time quantitative monitoring of early weak gas invasion signal. A deepwater drilling gas invasion monitoring method comprises the following steps: collecting ultrasonic echo signals of gas-liquid two-phase flow; extracting multi-scale fuzzy divergence entropy values in the ultrasonic echo signals; inputting the feature vectors in the multi-scale fuzzy divergence entropy values into the trained support vector machine classification model to obtain the gas holdup recognition result.

The invention relates to the technical field of oil and gas development drilling engineering, in particular to an overflow and leakage coexistence experiment device for simulating coupling of a stratum and a wellbore and a using method thereof.The overflow and leakage coexistence experiment device comprises a wellbore simulation unit, a drilling fluid circulation unit and a simulation medium injection unit, and the wellbore simulation unit comprises the wellbore and a drill column. The experimental device is mainly used for simulating the rule of influence of overflow leakage parameters, drilling fluid physical property parameters and the like on wellbore fluid flow parameters and the like when overflow and leakage coexistence occurs in a fractured stratum and a permeable stratum, and the experimental device can help deep water drilling and research of a well control method when overflow and leakage coexistence occurs. Compared with the existing experimental equipment, the actual coupling condition of the stratum and the shaft in the drilling process and the overflow or leakage working conditions of different types of stratums can be simulated, so that the simulation of abnormal working conditions under various stratum conditions can be realized; and the experiment result is more in line with the change rule of the shaft fluid under the actual working condition.

The utility model relates to the technical field of deepwater drilling, and discloses a connecting structure, a second connecting piece is sleeved on a first connecting piece, in order to enhance the connecting strength between the second connecting piece and the first connecting piece, a detachable locking piece is arranged on the second connecting piece, the locking piece comprises a locking part and an inserting part, the locking part is integrally in a sector ring shape, and the inserting part is arranged between the locking part and the first connecting piece. When the locking piece is located at the second position, the meshing teeth are clamped into the tooth grooves, the first connecting piece and the second connecting piece are connected through the locking piece, the contact face between the first connecting piece and the locking piece is a sector-ring-like contact face defined by the tooth faces of the meshing teeth, and the contact area of the first connecting piece and the locking piece is large. And the joint can bear larger load. The inserting part penetrates through the second connecting piece, the limiting piece can be connected with the inserting part and lock the locking piece at the second position, displacement of the locking piece after the first connecting piece and the second connecting piece are connected is avoided, and the connection reliability of the first connecting piece and the second connecting piece is guaranteed.

The invention discloses an ultra-deepwater drilling well leakage double-leakage layer positioning method, which comprises the following steps: acquiring the basis of each well section, calculating hydraulic parameters such as the flow velocity of drilling fluid in an annulus, calculating the Reynolds number of the drilling fluid in the annulus, judging the flow state, and selecting a corresponding annulus friction resistance coefficient formula according to the flow state; judging whether well leakage is returned or not according to whether drilling fluid returns from a well mouth, and selecting a model to calculate the depth of the double-leakage layer according to whether the well leakage is returned or not; determining the maximum value Kmax of the annulus pressure consumption distribution coefficient according to the fact that the first leakage layer depth is smaller than the second leakage layer depth, and enabling the annulus pressure consumption distribution coefficient to circulate within the range of (0, Kmax); and substituting the obtained first leakage layer depth and the second leakage layer depth into a post-well-leakage circulating vertical pressure expression to calculate post-well-leakage circulating vertical pressure, and when the post-well-leakage circulating vertical pressure is close to a post-well-leakage actually-measured vertical pressure value and the relation between the leakage layer depth and the length of the drill column meets the model requirement, ending the circulation. And obtaining a final double-leakage-layer leakage horizon calculation result.

The application discloses an anti-wear repair core for deepwater drilling of the sea, and relates to the technical field of offshore oil drilling and production equipment. The anti-wear repair core for deepwater drilling of the sea comprises a repair core assembly, the repair core assembly comprises a repair core body, a plurality of axial locking units arranged on the inner circumferential wall of the repair core body in a spaced manner and a recovery ring arranged on the top of the inner circumferential wall of the repair core body, the axial locking unit comprises an axial locking pin which can be horizontally moved towards the center of the repair core body, and a plurality of wellhead anti-rotation units for locking the wellhead are arranged on the outer circumferential wall of the repair core body; a retracting and releasing assembly, the retracting and releasing assembly comprises a lowering tool which passes through the repair core body and is used for connecting a drilling tool at the bottom, the lowering tool is externally provided with locking leaves which are equal in number to the axial locking pins and are opposite to the axial locking pins in position, transversely arranged grooves matched with the axial locking pins are formed on the locking leaves, and the top of the locking leaves is provided with a matching surface matched with the bottom of the recovery ring.

The utility model provides a direction adjusting assembly and deepwater drilling completion system integrated testing device, including fixed base and movable base, the upper surface of fixed base is provided with the groove, the groove bottom of groove is rotatablely connected with the turntable, the upper surface of turntable is provided with the connecting seat, the upper surface of connecting seat is embedded with the connecting shaft, and the connecting shaft is connected with the movable base. One end of the connecting shaft away from the connecting seat is connected with the lower surface of the movable base; two inclined blocks are symmetrically arranged on the lower surface of the movable base relative to the connecting shaft, and the two inclined blocks are located in the swinging direction of the connecting shaft; a sliding frame is further arranged on the upper surface of the rotating disc in a sliding mode. According to the utility model, the movable base swings left and right, and then the rotary table is used for driving the connecting seat and the sliding frame to rotate, so that the movable base rotates, the movable base swings obliquely, and the orientation of the movable base is adjusted; finally, multi-angle adjustment of the deepwater drilling and completion system integrated testing device installed on the upper surface of the movable base is achieved.

The invention discloses low-C-high-Mn-Ni-Cu corrosion-resistant L555-grade subsea pipeline steel and a preparation method thereof, belongs to the technical field of subsea pipeline steel manufacturing, and aims to solve the technical problem that existing L555-grade pipeline steel is poor in corrosion resistance and low-temperature toughness. The low-C high-Mn-Ni-Cu corrosion-resistant L555-grade subsea pipeline steel provided by the invention is prepared from the following components in percentage by mass: 0.031 to 0.045 percent of C, 2.00 to 2.10 percent of Mn, 0.15 to 0.22 percent of Si, 0.60 to 0.80 percent of Ni, 0.31 to 0.40 percent of Cu, 0.15 to 0.20 percent of Cr, 0.020 to 0.030 percent of Nb, 0.010 to 0.015 percent of Ti, less than or equal to 0.008 percent of P, less than or equal to 0.002 percent of S, less than or equal to 0.004 percent of N and the balance of Fe and inevitable impurities. The L555-grade subsea pipeline steel provided by the invention has good corrosion resistance and low-temperature toughness, and is suitable for deepwater drilling riser main pipes and other pressure-bearing service components.

The invention discloses a deepwater drilling guide pipe installation depth design method based on a mechanical relationship among operation parameters, which comprises the following steps of: performing preliminary design of deepwater drilling guide pipe installation by utilizing soil parameters of an adjacent well to obtain the bearing capacity and the mud entering depth of the deepwater drilling guide pipe; the deepwater drilling guide pipe is installed through the obtained deepwater drilling guide pipe bearing capacity and the obtained deepwater drilling guide pipe mud entering depth, the deepwater drilling guide pipe real-time bearing capacity is solved through the mechanical relation during deepwater drilling guide pipe installation operation, and therefore the deepwater drilling guide pipe installation depth is corrected in real time till deepwater drilling guide pipe installation is completed; when the deepwater drilling guide pipe is installed, the shearing strength of each area in the installation and descending process of the deepwater drilling guide pipe is obtained through operation parameter analysis, and a basis is provided for follow-up guide pipe depth theoretical design of an adjacent well. The accuracy of the designed depth of the drilling guide pipe can be guaranteed, and a large amount of seabed soil sampling cost can be saved.

The split type suction pile comprises an upper half part and a lower half part, the top of the upper half part is designed to be sealed, the bottom of the upper half part is designed to be open, a suction pump butt joint opening and an exhaust port are formed in the top of the upper half part, a reserved well opening is formed in the center of the interior of the upper half part, and the top of the lower half part is an open type horn mouth. The bottom of the lower half portion is open, a butt joint step and an anti-rotation structure are arranged in the lower half portion, the bottom of the upper half portion can enter the lower half portion and is clamped through the butt joint step and the anti-rotation structure, and hoisting structures are arranged on the outer wall of the upper half portion and the outer wall of the lower half portion respectively. According to the method, the underwater wellhead with excellent stability can be built on the ultra-deep water soft soil surface layer, and follow-up installation of equipment such as a Christmas tree is facilitated.

The present application relates to the field of oil and gas development drilling engineering, and is an experimental device for simulating overflow and leakage coexistence of formation and wellbore coupling and a use method thereof. The former includes a wellbore simulation unit, a drilling fluid circulation unit and a simulation medium injection unit. The wellbore simulation unit includes a wellbore and a drill string. The present application is mainly used for simulating the influence law of overflow and leakage parameters and drilling fluid physical property parameters on wellbore fluid flow parameters when overflow and leakage coexistence conditions occur in fractured formation and permeable formation. The experimental device can help the research of deepwater drilling and well control methods when overflow and leakage coexistence occurs. Compared with the existing experimental equipment, the present application can simulate the actual formation and wellbore coupling condition in the drilling process and the overflow or leakage condition of different types of formation. Not only can the abnormal conditions under various formation conditions be simulated, but also the experimental results are more in line with the change law of wellbore fluid under actual working conditions.

The present invention provides a pressure control drilling system and a drilling method for deepwater drilling in deep sea areas. The system includes a riser rotation control sub, an MPD hydraulic control sub, a riser annulus sealing device, a riser four-way joint, etc., which are integrated on an independent drilling riser joint. It forms a system with its corresponding key surface equipment: MPD choke manifolds, MPD hydraulic control manifolds, MPD buffer manifolds, MPD filter manifolds, MPD mud-gas separators, etc., and is used in conjunction with equipment such as riser boost pumps, metering tank pumps, rotary tables, mud diverters, riser telescopic joints, riser tension rings, drilling risers, subsea blowout preventer stacks, subsea wellheads, etc. of conventional deepwater drilling equipment. The present invention can be applied to carry out pressure control drilling and related drilling operations on equipment such as semi-submersible drilling platforms and drill ships in deep water (water depth above 300m).

The invention provides a deepwater drilling complex drilling multiphase flow simulation system and method, and the system comprises a drilling multiphase flow simulation database which is used for storing and managing multi-source heterogeneous data in a drilling process; the data service architecture module is used for constructing a data service architecture of drilling multiphase flow analogue simulation; the data standardization and cleaning fusion module is used for processing multi-source heterogeneous data in the drilling process; and the analogue simulation and real-time optimization module is used for carrying out analogue simulation and real-time optimization on drilling multiphase flow. According to the technical scheme, real-time simulation and optimization of multiphase flow in deepwater drilling engineering are achieved.

This invention relates to a method for preparing and applying a core-shell structured silica plugging agent with a rigid inner structure and a flexible outer structure for marine drilling fluids, belonging to the field of deepwater oil and gas drilling. This invention uses N-vinyl-2-pyrrolidone, dimethyl diallyl ammonium chloride, acrylamide, and 2-acrylamide-2-methylpropanesulfonic acid polymerized and grafted onto the surface of nano-silica to form a core-shell structured silica plugging agent with a rigid inner structure and a flexible outer structure. By utilizing the rigid plugging of nanomaterials and the flexible plugging of polymer deformation, this method effectively seals the micro- and nano-pores of shale and mudstone, thereby maintaining wellbore stability. Simultaneously, it effectively inhibits the secondary formation of hydrates, improving the safety and efficiency of deepwater drilling. Furthermore, the plugging agent of this invention reduces the need for large amounts of thermodynamic inhibitors, saving costs and possessing environmentally friendly properties.

The invention belongs to the technical field of marine drilling riser, and relates to a deepwater drilling riser fatigue life management method and system, and the method comprises the steps: obtaining the configuration information and structure parameter information of a riser through reading an electronic tag of the riser; according to the configuration information and the structure parameter information of the marine riser, wave-induced fatigue and vortex-induced fatigue analysis is carried out, so that the comprehensive fatigue damage and the service life of the marine riser are predicted; performing risk assessment according to wave-induced fatigue and vortex-induced fatigue analysis results; according to a risk assessment result, overhaul optimization is carried out, high-risk items are directly overhauled, for medium-low-risk items, the total process cost is calculated based on the defect type of the marine riser, a genetic algorithm optimization method is adopted, the minimum process use cost is used as a target function, self-adaptive optimization is carried out, and the most economical overhaul scheme of the marine riser is obtained. Individual identity information is given to the marine riser, information traceability in the whole life cycle is ensured, and automatic updating and efficient management of marine riser data are achieved.

The present application relates to a kind of marine drilling fluid with the preparation method and application of inner rigid outer soft core-shell structure nano zinc oxide blocking agent, the present application is polymerized by acrylamide, 2-acrylamide-2-methylpropane sulfonic acid and grafted on the surface of modified nano zinc oxide, and the micro-morphology is formed for the core-shell structure zinc oxide blocking agent of inner rigid outer soft;With the rigid plugging of nanometer material and the flexible plugging of the deformation filling of high molecular polymer, soft and hard combination, high efficient plugging shale micro-nanopore, further maintain wellbore stability, while effectively inhibit the secondary generation of hydrate, improve the safety and efficiency of deepwater drilling, preparation method is simple, raw material is cheap and easy to obtain, high efficiency and environmental protection;And good compatibility with drilling fluid.Effective plugging of micro-nanopore in deepwater formation can prevent drilling fluid filtrate from invading the formation, reduce reservoir hydration dispersion and improve the safety of deepwater drilling and production process.

The invention provides a deep sea drilling ship module ladder tower, which relates to the field of deep sea drilling ships, comprises a tower body and a base connected to a drilling ship deck, and is characterized by further comprising a hinge compensation mechanism arranged between the tower body and the base and comprising a spherical hinge assembly and an actuator group; the in-tower balance system is integrated in the tower body and comprises a hydraulic buffer device and an energy storage device communicated with the hydraulic buffer device; the lateral stabilizing devices are symmetrically arranged on the two sides of the tower body and comprise telescopic guiding pieces and bearing wheels arranged at the ends of the guiding pieces. And the retractable connecting platform is hinged to the top of the tower body and comprises a folding frame plate group and a liftable guardrail group. Through highly-integrated functional modules and intelligent coordination control, efficient and stable operation in a limited space is achieved, and the overall safety and economical efficiency of deep sea drilling operation are improved.

The invention discloses a control method and system of a deepwater drilling device, electronic equipment and a storage medium, and belongs to the technical field of drilling technologies. The deepwater drilling device comprises a riser pressure manifold, a drill rod, a marine riser and a rotation control device, the rotation control device is installed on the upper portion of the marine riser, a fluid conveying line between the rotation control device and the circulating pool comprises a first line and a second line which are connected in parallel, and the first line comprises a first return pipeline. The first line comprises a first return pipeline and a riser pressure manifold which are connected in series, the second line comprises a second return pipeline and a choke manifold which are connected in series, a first drilling pump is arranged in the first line, a second drilling pump is arranged in the second line, a third drilling pump is arranged in the riser pressure manifold, and the equivalent circulation density control method in deepwater drilling comprises the steps that the current working condition of the deepwater drilling device is determined; and selecting a corresponding control mode according to the current working condition. According to the method, the wellbore pressure can be effectively controlled, and the safety and efficiency of deepwater drilling are improved.

The invention relates to the field of offshore oil engineering equipment, and discloses a deepwater drilling pipe fatigue monitoring test device and method. According to the invention, the stress data and the stress response data of the deepwater drilling pipe model under the wave current coupling effect and the top reciprocating motion can be tested, the fatigue monitoring damage of the deepwater drilling pipe model is evaluated according to the stress data and the stress response data, and then the fatigue monitoring damage of the deepwater drilling riser and the underwater wellhead system conduit section is evaluated. And an effective fatigue monitoring test mode is provided for a deepwater drilling riser and an underwater wellhead system conduit section.

The invention provides a monitoring-based deepwater drilling riser system state prediction method, medium and system, and belongs to the technical field of offshore oil and gas development.The monitoring-based deepwater drilling riser system state prediction method, medium and system comprises the following steps that firstly, the state of a deepwater drilling riser system needing to be monitored is determined; establishing a deepwater drilling riser system mechanical simulation model, establishing a database by using the simulation model, performing initial parameter optimization on the gated circulation network through an ant colony algorithm, training the gated circulation network by using the database to establish a deepwater drilling riser system prediction model, and constructing a test set; verifying a deepwater drilling riser system state prediction model by using the determined monitoring state, and optimizing the prediction model based on a verification result; the prediction precision can be improved, and the adaptability of the prediction method is improved by using the prediction algorithm.

The invention discloses a top hydraulic tensioning type drilling riser system suitable for a cylindrical floating deepwater dry platform, which comprises a production riser system, a tensioning system, a wellhead connecting system and an underwater isolation barrier system, the production riser system comprises a flow divider, a telescopic joint, an overwater blowout preventer, a platform moon pool structure and a single drilling riser, the single drilling riser is of a hollow tubular structure, the flow divider, the telescopic joint, the overwater blowout preventer, the tensioning system, the platform moon pool structure and the top of the single drilling riser are sequentially connected, and the bottom of the single drilling riser is connected with an underwater wellhead through the wellhead connecting system and the underwater isolation barrier system. Based on an overwater blowout preventer mode, a huge, overweight and high-cost underwater blowout preventer does not need to be used, then the deepwater drilling operation cost is reduced, and through combined use of the overwater blowout preventer and the underwater isolation barrier system, the drilling operation safety is effectively improved, and the operation risk is reduced.