Abstract: A high-efficiency yield-increasing exploitation method for natural gas hydrates includes steps of drilling of natural gas hydrate reservoirs along horizontal wells, seepage increasing by fracturing for fracture forming and stability improvement by grouting in the natural gas hydrate reservoirs, and yield improvement by combined exploitation of depressurization of the horizontal wells and heat injection; according to the present invention, drilling time is shortened by rapid drilling along the horizontal wells, the permeability of the reservoirs can be effectively improved by fracturing for fracture forming, the stability of the reservoirs can be improved by injecting foam cement slurry into the reservoirs, and the yield of the natural gas hydrates can be improved by the combined exploitation method of depressurization of the horizontal wells and heat injection.

Abstract: A high-efficiency yield-increasing exploitation method for natural gas hydrates includes steps of drilling of natural gas hydrate reservoirs along horizontal wells, seepage increasing by fracturing for fracture forming and stability improvement by grouting in the natural gas hydrate reservoirs, and yield improvement by combined exploitation of depressurization of the horizontal wells and heat injection; according to the present invention, drilling time is shortened by rapid drilling along the horizontal wells, the permeability of the reservoirs can be effectively improved by fracturing for fracture forming, the stability of the reservoirs can be improved by injecting by the combined exploitation method of depressurization of the horizontal wells and heat injection.

Abstract: An apparatus for preventing and controlling secondary generation of hydrates in a wellbore during depressurization exploitation of offshore natural gas hydrates includes a gas recovery pipe column, a water recovery pipe column, a gas-liquid mixed transportation pipe section, a data collecting and processing unit, and a reaction control apparatus; according to characteristics of different exploitation pipe columns, three injection pipelines and three monitoring points are arranged to predict dynamic changes in a secondary generation risk of the hydrates throughout the wellbore; measures for preventing and controlling the secondary generation of the hydrates are taken at different pipe column positions by the integrated utilization of inhibitor injection, heating for pipe columns, the additional arrangement of electric submersible pumps, and other methods.

Abstract: A preparation method for and an application of a modified siloxane-based supercritical carbon dioxide thickener are disclosed. The method includes the following steps: using 1,3-diallyl-1,3,5-triazine-2,4,6-trione as a polymerization monomer, and dropwise adding 1,3,5,7-tetramethylcyclotetrasiloxane for hydrosilylation in the presence of a catalyst to obtain a modified siloxane polymer. The obtained modified siloxane polymer is directly used as a supercritical carbon dioxide thickener without purification post-treatment; when in use, the modified siloxane polymer is prepared into a solution with a concentration of 1-2%, has an excellent thickening effect with no cosolvent required, and has high solubility in carbon dioxide and high temperature resistance.

Abstract: A drilling well underground kick processing method and device are described.

Abstract: A drilling well underground kick processing method and device are described.

Abstract: A pressure compensation device with an accumulator group for controlled pressure drilling includes an electrical flat valve, a check valve, an accumulator group, a flanged pup joint and a support base. The electrical flat valve is connected to the check valve and is mounted on a top surface of the support base. The accumulator group mounted on the whole support base is a pre-storage pressure compensation device for controlled pressure drilling, and is located at a downstream position of the check valve. The liquid inlet end of the accumulator group is connected to the check valve, and the liquid discharge end is connected to the flanged pup joint.

Abstract: The present invention relates to the field of natural gas production, and discloses a well structure for natural gas hydrate production, which comprises: a natural gas production well (12); an injection well (4) capable of extending into a geothermal reservoir and injecting a heat-carrying fluid; a curved connecting well (7), the inlet end of the curved connecting well (7) is connected to the outlet end of the injection well (4); a hydrate production horizontal well (10), which may be arranged in a shallow hydrate reservoir (9), the curved connecting well (7) and the hydrate production horizontal well (10) are connected by an ascending well section (8). With the above technical scheme, the high curvature connected well connecting the horizontal well and the vertical well can be located in the bottom layer below the hydrate reservoir, enhancing the stability and production efficiency of the gas hydrate production well.

Abstract: The present invention provides a method and equipment for optimizing hydraulic parameters of deepwater managed pressure drilling in real time. The method comprises: acquiring overflow parameters in the current drilling process, performing preprocessing and feature extraction on the overflow parameters, and inputting the overflow parameters into trained support vector machine identification models for overflow judgment. If overflow occurs at the current drilling depth, reducing an opening of a throttle valve and increasing a displacement of a submarine pump, measuring a wellhead back pressure and calculating a bottom hole pressure, and judging whether overflow continues is performed.

Abstract: The present invention relates to the field of natural gas production, and discloses a well structure for natural gas hydrate production, which comprises: a natural gas production well (12); an injection well (4) capable of extending into a geothermal reservoir and injecting a heat-carrying fluid; a high curvature connecting well (7), the inlet end of the high curvature connecting well (7) is connected to the outlet end of the injection well (4); a hydrate production horizontal well (10), which may be arranged in a shallow hydrate reservoir (9), the high curvature connecting well (7) and the hydrate production horizontal well (10) are connected by an ascending well section (8), and connected with the natural gas production well (12). With the above technical scheme, the high curvature connected well connecting the horizontal well and the vertical well can be located in the bottom layer below the hydrate reservoir, enhancing the stability and production efficiency of the gas hydrate production well.

Abstract: An active control method and system for wellbore pressure in open-cycle drilling in marine natural gas hydrates. The system comprises a drilling system, a drilling fluid injection system, and a data processing system for conducting the drilling operation.

Abstract: An active control method and control device for wellbore pressure in the open-cycle drilling of marine natural gas hydrates comprises following steps: (1) optimized design of drilling parameter; (2) carry out open-cycle drilling according to the designed drilling parameters; (3) utilize the APWD to monitor the bottom-hole temperature and the bottom-hole pressure in real time for real-time correction of the wellbore annulus temperature and pressure calculation models; determine whether a hydrate decomposition has occurred in the annulus and then infer whether a shallow gas intrusion has occurred in the bottom hole; (4) Intelligent active control: control and adjust the mixed density of drilling fluid, the injection displacement of drilling fluid as well as the injection temperature of drilling fluid and the pump pressure in wellhead automatically during the well killing based on the real-time treatment results of the computer terminal for the signal fluctuations detected by the APWD.

Abstract: The well killing device comprises: a first path; a flow regulating device; a pressure detector and a controlling device. The controlling device may control the discharge amount of the killing fluid in different killing stages according to the gas-fluid two-phase flow theory, the pressure of the killing fluid at the wellhead, and the rising speed of the drilling column.

Abstract: The invention relates to the field of stratum drilling, and in particular to a control method and a control device for drilling operations. The control method comprises: detecting whether an overflow occurs in a well; controlling the wellhead back pressure based on a preset bottom hole pressure when no overflow occurs in the well, in order to keep the bottom hole pressure stable; and performing a shut-in operation and controlling the wellhead back pressure based on the increase in fluid discharge returned from an annulus of the well when an overflow occurs in the well, so as to keep the bottom hole pressure stable and prevent the gas in the stratum from continuing to invade into the drilling fluid during the process that the overflow drilling fluid is discharged from the bottom of the well.

Abstract: The present invention relates to the field of drilling, and provides an anti-settling apparatus and a method and apparatus for checking the same, and an apparatus for preventing settlement of a well. The anti-settling apparatus of the present invention is installed in the wellhead region of the well during drilling to prevent the well from settlement. The anti-settling apparatus generally includes: an anti-settling base having an opening corresponding to the wellhead formed at the center thereof, the anti-settling base being disposed in the wellhead region during drilling; and an interlocking member 5 disposed at the opening to connect and fix a casing provided in the well with the anti-settling base. The apparatus for preventing settlement of a well comprises the anti-settling apparatus and checking method for the anti-settling apparatus.

Abstract: The present invention relates to the field of marine hydrate reserve recovery technology, and discloses a homocentric squares-shaped well structure for marine hydrate reserve recovery utilizing geothermal heat and a method thereof. The present invention employs a homocentric squares-shaped well structure and utilizes heat-carrying fluid to transfer the energy in a geothermal reservoir to a hydrate reservoir to promote dissociation of natural gas hydrates. The homocentric squares-shaped well structure can realize cyclic utilization of the heat-carrying fluid while improving heat conduction efficiency, and has advantages including high recovery rate, low recovery cost, low energy loss, and high heat utilization efficiency, etc.

Abstract: The present invention relates to offshore oil and gas exploration drilling field and, in particular, to a surface layer conductor running tool for deep-water well drilling, which is used to run a conductor to a designated position, so that the drill stem can be released and the drilling can be continued. The surface layer conductor running tool for deep-water well drilling comprises a mandrel, an inner sleeve, an outer sleeve, and a main body, wherein the inner sleeve, the outer sleeve, and the main body are fitted over the mandrel sequentially; the inner sleeve can slide up and down but cannot rotate in relation to the mandrel, the outer sleeve and the inner sleeve are connected via a transmission thread pair, and the main body is situated on the inner sleeve; a retaining pawl penetrating the main body and radially slidable in horizontal direction; and an anti-rotation pin penetrating the main body and the outer sleeve, so that the outer sleeve can move up and down in the main body only, but cannot rotate.

Abstract: The present invention provides wellbore pressure control system and method for well cementation stages, and relates to the offshore oil and gas exploitation field. The wellbore pressure control system comprises: an injection pump; and a control device, configured to control the injection pump to inject a fluid or gas through an injection pipeline to a return pipeline that communicates with an annular space of the wellbore to decrease the pressure in the return pipeline and thereby decrease the pressure in the annular space, wherein, the density of the fluid or gas is lower than the density of a drilling fluid in the annular space. The technical scheme of the present invention can effectively prevent leaky zones from being fractured by high-density cement slurry in the well cementation process that may cause safety accidents such as well kick and well blowout, etc.

Abstract: The present invention provides a measuring unit, a kick information identification apparatus and method, and relates to the oil and gas well engineering field. The measuring unit comprises: a throttling device, mounted on a drill stem; sensors, arranged at the two sides of the throttling device, and configured to sense the pressure and/or temperature at the two sides of the throttling device; and a signal transmitter, configured to transmit the pressure and/or temperature values. The present invention employs a throttling device and measures the pressure drop and/or temperature difference across the throttling device, and can identify kick information successfully according to the pressure drop and/or temperature difference. Even in the case of horizontal wells where the flow and pressure variations are not apparent, the present invention can still attain a good kick information identification effect.

Abstract: The present invention relates to the field of oil and natural gas well cementation engineering, in particular to a foam stabilizer composition, foamed cement slurry and an additive composition thereof. The foam stabilizer composition comprises C6-C20 alkyl amido alkyl amine oxide, C6-C20 alkyl amido alkyl betaine, and triterpenoid saponin compound. The foam stabilizer composition provided in the present invention is helpful for forming foamed cement slurry that has high foam stability, and the foam stabilizer composition can work with other active components in the foamed slurry additive composition provided in the present invention to enable the foamed cement slurry that contains the additive composition to obtain low density, high foam stability, low permeability, and high compressive strength, which is especially applicable to well cementing operation in an oil and natural gas exploration and development process.