摘要:
A subpart (430) of a drill string (211) is described having an outer circumferential surface which is contoured and adapted to engage the wall of the borehole with a small angle of attack while exerting during rotary drilling operations an compacting pressure on mud cake and/or cuttings present in the annulus between the drill string and the borehole.
摘要:
A subpart of a drill string is described having an outer circumferential surface which is contoured and adapted to engage the wall of the borehole with a small angle of attack while exerting during rotary drilling operations an compacting pressure on mud cake and/or cuttings present in the annulus between the drill string and the borehole.
摘要:
A subpart of a drill string is described having an outer circumferential surface which is contoured and adapted to engage the wall of the borehole with a small angle of attack while exerting during rotary drilling operations an compacting pressure on mud cake and/or cuttings present in the annulus between the drill string and the borehole.
摘要:
A subpart of a drill string is described having an outer circumferential surface which is contoured and adapted to engage the wall of the borehole with a small angle of attack while exerting during rotary drilling operations an compacting pressure on mud cake and/or cuttings present in the annulus between the drill string and the borehole.
摘要:
A subpart of a drill string is described having an outer circumferential surface which is contoured and adapted to engage the wall of the borehole with a small angle of attack while exerting during rotary drilling operations an compacting pressure on mud cake and/or cuttings present in the annulus between the drill string and the borehole.
摘要:
The present invention generally relates to an apparatus and methods for improving the stability of a wellbore during drilling operations using a rotary drill string. More specifically, embodiments of the present invention provide systems and methods for enhancing the performance of the filter or mud cake layer on the wall of the wellbore as a protective and isolating layer.
摘要:
A method of fracturing a rock formation is provided including placing through a wellbore penetrating the rock formation propellants in a cavity located at a radial distance from the wellbore and igniting the propellants to cause a pressure sufficient to fracture the formation.
摘要:
The invention relates to a method for obtaining gelled hydrocarbon compositions, and their application in the hydraulic fracturing of rocks.The gelling method according to the invention uses as an activator a partially neutralized aluminum acid salt.
摘要:
This invention relates to the construction of well such as oil and gas wells using techniques based on drilling small lateral wells from a main well. The problem of narrow pressure window is solved by the use of constructions techniques that are based on the use of lateral boreholes, i.e. secondary boreholes that are drilled a main borehole, wherein a method of constructing a well comprises drilling a main borehole extending from the surface through one or more underground formations, drilling a plurality of lateral boreholes extending from the main borehole into surrounding formations, wherein the lateral boreholes are substantially shorter and of smaller diameter than the main borehole; and wherein each lateral borehole is separated from its neighboring lateral boreholes by a relatively short distance. Drilling of the lateral boreholes can be for to extend 5-60 meters from the main borehole with a diameter in the range 3.8-10 cm by the lateral boreholes at an axial spacing of less than a few meters in the main borehole. Drilling of more than one lateral borehole can be done at the same depth in the main borehole with a trajectory that deviates from the main borehole by less than 10° or with trajectories that extend in a plane that does not contain the main borehole.
摘要:
An apparatus for modifying the wall surface of a borehole drilled through an underground formation. The apparatus comprises a tool body that can be introduced into the borehole using a conveyance system so as to be moveable along the borehole, and one or more members arranged so as to be able to be urged against, and moved across at least part of the borehole wall in order to work the surface thereof and modify its properties. A method of modifying the wall surface comprises positioning the tool body in the borehole at a location of interest using the conveyance system, urging the members against the borehole wall with sufficient force to modify the properties of the surface thereof, and moving the members across the surface of the borehole wall.