A core extracting apparatus and method is provided. The annular core extracting apparatus may be dimensioned so as to be lowered into the core groove circumscribing a drilled core. The core extracting apparatus has a cylindrical outer casing encasing a cylindrical inner grabber in a release condition, wherein the inner grabber is adapted to move from the release condition to a gripping condition as the outer casing is lifted from the core groove. The inner grabber provides a plurality of peripheral fingers, each finger providing a wedge along its outer surface, wherein the release condition each wedge nests in a taper provided by the outer casing so that when the inner grabber moves to the gripping condition the wedge interfaces with the outer casing to urge the fingers inward, gripping the core and extracting it from the drilling hole.

A core extracting apparatus and method is provided. The annular core extracting apparatus may be dimensioned so as to be lowered into the core groove circumscribing a drilled core. The core extracting apparatus has a cylindrical outer casing encasing a cylindrical inner grabber in a release condition, wherein the inner grabber is adapted to move from the release condition to a gripping condition as the outer casing is lifted from the core groove. The inner grabber provides a plurality of peripheral fingers, each finger providing a wedge along its outer surface, wherein the release condition each wedge nests in a taper provided by the outer casing so that when the inner grabber moves to the gripping condition the wedge interfaces with the outer casing to urge the fingers inward, gripping the core and extracting it from the drilling hole.

A core lifter and method for making same for use in a drilling system. The core lifter can include a tubular body having an exterior surface and an interior surface and can have a plurality of longitudinally-oriented recesses formed in the exterior surface of the tubular body of the core lifter and extending radially inwardly relative to the central axis of the core lifter. The plurality of longitudinally-oriented recesses formed in the exterior surface of the tubular body of the core lifter can extend along at least 50 percent of the length of the core lifter.

A core lifter and method for making same for use in a drilling system. The core lifter can include a tubular body having an exterior surface and an interior surface and can have a plurality of longitudinally-oriented recesses formed in the exterior surface of the tubular body of the core lifter and extending radially inwardly relative to the central axis of the core lifter. The plurality of longitudinally-oriented recesses formed in the exterior surface of the tubular body of the core lifter can extend along at least 50 percent of the length of the core lifter.

A core barrel sealing structure includes a core barrel, a drilling machine outer barrel, a chain mail-type flap valve and a trigger mechanism. The flap valve includes a valve seat and a chain mail-type valve flap. The trigger mechanism includes a trigger inner barrel and a trigger block. The trigger block is arranged in a through hole in a sidewall of the trigger inner barrel, and an inner wall of the drilling machine outer barrel is provided with a recessed opening adapted to the trigger block. When the core barrel is located in the valve seat, the valve flap is opened by 90° and is located between the trigger inner barrel and the drilling machine outer barrel. When the core barrel is lifted upwards, the valve flap returns to a top face of the valve seat to make sealing contact with a sealing face of a valve opening.

A core barrel sealing structure includes a core barrel, a drilling machine outer barrel, a chain mail-type flap valve and a trigger mechanism. The flap valve includes a valve seat and a chain mail-type valve flap. The trigger mechanism includes a trigger inner barrel and a trigger block. The trigger block is arranged in a through hole in a sidewall of the trigger inner barrel, and an inner wall of the drilling machine outer barrel is provided with a recessed opening adapted to the trigger block. When the core barrel is located in the valve seat, the valve flap is opened by 90° and is located between the trigger inner barrel and the drilling machine outer barrel. When the core barrel is lifted upwards, the valve flap returns to a top face of the valve seat to make sealing contact with a sealing face of a valve opening.

A core barrel sealing structure includes a core barrel, a drilling machine outer barrel, a chain mail-type flap valve and a trigger mechanism. The flap valve includes a valve seat and a chain mail-type valve flap. The trigger mechanism includes a trigger inner barrel and a trigger block. The trigger block is arranged in a through hole in a sidewall of the trigger inner barrel, and an inner wall of the drilling machine outer barrel is provided with a recessed opening adapted to the trigger block. When the core barrel is located in the valve seat, the valve flap is opened by 90° and is located between the trigger inner barrel and the drilling machine outer barrel. When the core barrel is lifted upwards, the valve flap returns to a top face of the valve seat to make sealing contact with a sealing face of a valve opening.

A core barrel sealing structure includes a core barrel, a drilling machine outer barrel, a chain mail-type flap valve and a trigger mechanism. The flap valve includes a valve seat and a chain mail-type valve flap. The trigger mechanism includes a trigger inner barrel and a trigger block. The trigger block is arranged in a through hole in a sidewall of the trigger inner barrel, and an inner wall of the drilling machine outer barrel is provided with a recessed opening adapted to the trigger block. When the core barrel is located in the valve seat, the valve flap is opened by 90° and is located between the trigger inner barrel and the drilling machine outer barrel. When the core barrel is lifted upwards, the valve flap returns to a top face of the valve seat to make sealing contact with a sealing face of a valve opening.

A core lifter and method for making same for use in a drilling system. The core lifter can include a tubular body having an exterior surface and an interior surface and can have a plurality of longitudinally-oriented recesses formed in the exterior surface of the tubular body of the core lifter and extending radially inwardly relative to the central axis of the core lifter. The plurality of longitudinally-oriented recesses formed in the exterior surface of the tubular body of the core lifter can extend along at least 50 percent of the length of the core lifter.

A core lifter and method for making same for use in a drilling system. The core lifter can include a tubular body having an exterior surface and an interior surface and can have a plurality of longitudinally-oriented recesses formed in the exterior surface of the tubular body of the core lifter and extending radially inwardly relative to the central axis of the core lifter. The plurality of longitudinally-oriented recesses formed in the exterior surface of the tubular body of the core lifter can extend along at least 50 percent of the length of the core lifter.