A method for shutting off a wet interval of a wellbore includes producing hydrocarbons from a hydrocarbon bearing subterranean formation through a production string installed in the wellbore, identifying the wet interval of the wellbore, perforating the production string in the wet interval using an explosive-free punch tool to produce a plurality of openings in the production string, isolating the production string in the wet interval, treating the wet interval with a sealing composition injected through the plurality of openings into an annulus of the wellbore in the wet interval, and restoring a fluid flow path through the production string in the wet interval. The restored fluid flow path through the wet interval enables continued production of hydrocarbons from downhole intervals, while the sealing composition cured in the annulus provides a barrier to prevent fluid flow from the wet interval into the production string.

A mechanical service tool that may include one or more anchors, a cutter, a communication and control system, and one or more sensors, as well as methods for operating the mechanical service tool, are provided. The one or more anchors may extend radially from the mechanical service tool and the cutter may move relative to the mechanical service tool. The cutter may include a drilling bit. The communication and control system may obtain remote commands that control the cutter, the one or more anchors, or both. The one or more sensors may detect operational conditions of the mechanical service tool and may be operatively coupled to the communication and control system.

The present invention relates to a downhole operational tool for moving a tool part between a retracted position and a projected position in a well. The downhole operational tool comprises a tool body having an axial extension; the tool part being movable perpendicularly to the axial extension between the retracted position and the projected position; a projection actuator configured to project the tool part from the tool body by means of hydraulics, the projection actuator comprising an actuator housing and a projection piston configured to slide inside the actuator housing, the tool part being connected with the projection piston; and a retraction actuator comprising a spring element configured to retract the tool part into the tool body, the retraction actuator being connected with the projection piston so that when the projection actuator projects the tool part, the spring element is compressed. The spring element is arranged outside the actuator housing.

A perforation system includes: a perforating tool including a main body and a perforating head disposed within the main body; a wireline electrically coupled to the perforating head; a pulse generator electrically coupled to the wireline; and a power supply electrically coupled to the pulse generator. Upon electrification of the perforating head, a spark discharged from the perforating head arcs to a perforation target location.

A perforation system includes: a perforating tool including a main body and a perforating head disposed within the main body; a wireline electrically coupled to the perforating head; a pulse generator electrically coupled to the wireline; and a power supply electrically coupled to the pulse generator. Upon electrification of the perforating head, a spark discharged from the perforating head arcs to a perforation target location.

A tool for both perforating a well casing in a hydrocarbon formation and for subsequently fracturing the formation. The tool allows not only perforation and fracking, but in a preferred embodiment allows both perforation of the casing and fracking of the formation without having to further reposition the tool within the wellbore. The tool comprises a cylindrical member having thereon an upper and lower seal member and a longitudinal bore therein, and a cooperating piston which operates a punch to perforate the well casing. A flushing port is provided immediately uphole of the upper seal member, which port when said tool is lowered downhole allows fluid flowing up a longitudinal channel to flush an annular region immediately uphole of said upper seal, thereby greatly reducing the incidence of sand impaction and thereby better allow the tool to be moved uphole for further perforation and fluid injection into the formation.

A tool for both perforating a well casing in a hydrocarbon formation and for subsequently fracturing the formation. The tool allows not only perforation and fracking, but in a preferred embodiment allows both perforation of the casing and fracking of the formation without having to further reposition the tool within the wellbore. The tool comprises a cylindrical member having thereon an upper and lower seal member and a longitudinal bore therein, and a cooperating piston which operates a punch to perforate the well casing. A flushing port is provided immediately uphole of the upper seal member, which port when said tool is lowered downhole allows fluid flowing up a longitudinal channel to flush an annular region immediately uphole of said upper seal, thereby greatly reducing the incidence of sand impaction and thereby better allow the tool to be moved uphole for further perforation and fluid injection into the formation.

A perforation cluster of a longitudinal section of a wellbore is provided. The wellbore is for hydraulic fracturing in a preferred direction of a subsurface surrounding the longitudinal section. The longitudinal section has a longitudinal axis in a longitudinal direction and defining a radial direction about the longitudinal axis. The perforation cluster includes all of the perforations of the wellbore within the longitudinal section. The perforations are separated in the longitudinal and radial directions. Two perforations are adjacent in the longitudinal direction and have a first diameter. They also have respective centers that are aligned in the preferred direction with respect to the longitudinal axis and 180° apart in the radial direction, for initiating fractures through hydraulic fracturing in the subsurface. The remaining perforations have a second diameter smaller than the first diameter.

A multi-perforating assembly can include a housing containing a rotor. The rotor can be axially stroked by a multi-stroker tool. Upon axial movement, the rotor can cooperate with the housing to incrementally rotate. Axial movement of the rotor can cause a multi-perforating cartridge to radially pierce. Rotation of the rotor combined with piercing of the multi-perforating cartridge can enable multiple piercings to be easily and quickly performed in a single run. A multi-perforating cartridge can include a blade pivotally attached to a slider. The blade can be pulled past ports in a cartridge housing whereupon biasing springs can push the blade into the ports and a support pin can push the blade into piercing positions before pushing the blade into transitional positions, after which the blade can be biased into the subsequent port.

A multi-perforating assembly can include a housing containing a rotor. The rotor can be axially stroked by a multi-stroker tool. Upon axial movement, the rotor can cooperate with the housing to incrementally rotate. Axial movement of the rotor can cause a multi-perforating cartridge to radially pierce. Rotation of the rotor combined with piercing of the multi-perforating cartridge can enable multiple piercings to be easily and quickly performed in a single run. A multi-perforating cartridge can include a blade pivotally attached to a slider. The blade can be pulled past ports in a cartridge housing whereupon biasing springs can push the blade into the ports and a support pin can push the blade into piercing positions before pushing the blade into transitional positions, after which the blade can be biased into the subsequent port.