Abstract: 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.

Abstract: A drilling apparatus including a drill collar forming part of a primary drilling assembly and having an outward opening groove in the side thereof, and a secondary drilling assembly. The secondary drilling assembly includes a tubular drill string connected at one end to the drill collar, a drilling motor mounted in the drill string, and a drill bit mounted at the other end of the drill string and connected to the drilling motor. The secondary drilling assembly is mounted in the drill collar so as to be movable between a first position in which the drill bit is seated in the groove, and a second position in which the bit projects laterally from the groove in the side of the drill collar.

Abstract: A drilling system comprising a rotatable drill pipe 12 connected to a tractor unit 10, and a steerable drilling system 18, 20, 22, connected to and movable by the tractor unit 10.

Abstract: A drilling system comprising a rotatable drill pipe 12 connected to a tractor unit 10, and a steerable drilling system 18, 20, 22, connected to and movable by the tractor unit 10.

Abstract: The invention relates to apparatus and methods useful for drilling lateral boreholes into a formation surrounding a main borehole. Proposed technique can be used for drilling of laterals which does not require such significant interruptions to deploy the small BHA and is based on the use of a drilling apparatus, comprising a drill collar forming part of a primary drilling assembly and having an outward opening groove in the side thereof, a secondary drilling assembly, comprising a tubular drill string connected at one end to the drill collar, a drilling motor mounted in the drill string, a drill bit mounted at the other end of the drill string and connected to the drilling motor, wherein the secondary drilling assembly is mounted in the drill collar so as to be movable between a first position in which the drill bit is seated in the groove, and a second position in which the bit projects laterally from the groove in the side of the drill collar.

Abstract: 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 neighbouring lateral boreholes by a relatively short distance. Drilling of the lateral boreholes can be for to extend 5-60 metres from the main borehole with a diameter in the range 3.

Abstract: Apparatus and methods to perform operations in a wellbore using downhole tools having movable sections are described. In one described example, a downhole tool for use in a wellbore includes a first extendable anchor to contact a wall of the wellbore to fix the tool at a location in the wellbore. The downhole tool also includes a first tool of the downhole tool to perform a first operation at the location in the wellbore, and a second tool of the downhole tool spaced from the first tool and to perform a second operation. Additionally, the downhole tool includes an extendable member to move the second tool to the location while the anchor is in contact with the wall of the wellbore to perform the second operation after the first operation.

Abstract: Apparatus and methods to perform operations in a wellbore using downhole tools having movable sections are described. In one described example, a downhole tool for use in a wellbore includes a first extendable anchor to contact a wall of the wellbore to fix the tool at a location in the wellbore. The downhole tool also includes a first tool of the downhole tool to perform a first operation at the location in the wellbore, and a second tool of the downhole tool spaced from the first tool and to perform a second operation. Additionally, the downhole tool includes an extendable member to move the second tool to the location while the anchor is in contact with the wall of the wellbore to perform the second operation after the first operation.