Disclosed is a system for the in-situ retained coring of a rock sample, the system comprising a driving module (300), a retaining module (200), and a coring module (100) which are connected in sequence, wherein the coring module (100) comprises a rock core drilling tool and a rock core sample storage cylinder, the retaining module (200) comprises a rock core sample retaining compartment; the driving module comprises a coring drill machine that comprises a drill machine outer cylinder unlocking mechanism; the rock core drilling tool comprises a coring drill tool, a core catcher (11), and an inner core pipe (12); the coring drill tool comprises an outer core pipe (13) and a hollow drill bit (14); and the rock core sample retaining compartment comprises an inner coring cylinder (28), an outer coring cylinder (26), and an energy accumulator (229). The system is conducive to retaining the state of a rock core in an in-situ environment, and can improve the drilling rate and improve the coring efficiency.

A device and a method for transferring and storing a deep in-situ core in a sealed and pressure-maintaining manner includes a pressure vessel, a sealed storage vessel, a control system, a pressure regulation system and at least one spherical valve. The pressure vessel includes a first barrel and a first end sealing piston mounted at a first end of the first barrel and being slidable in the pressure vessel. The sealed storage vessel includes a second barrel and a second end sealing piston which is mounted at a first end of the second barrel. At least one spherical valve is connected between the first barrel and the second barrel. The pressure regulation system is configured for regulating an amount of water in the second barrel. The control system includes a first pressure sensor, a second pressure sensor, and a controller.

A device and a method for transferring and storing a deep in-situ core in a sealed and pressure-maintaining manner includes a pressure vessel, a sealed storage vessel, a control system, a pressure regulation system and at least one spherical valve. The pressure vessel includes a first barrel and a first end sealing piston mounted at a first end of the first barrel and being slidable in the pressure vessel. The sealed storage vessel includes a second barrel and a second end sealing piston which is mounted at a first end of the second barrel. At least one spherical valve is connected between the first barrel and the second barrel. The pressure regulation system is configured for regulating an amount of water in the second barrel. The control system includes a first pressure sensor, a second pressure sensor, and a controller.

A core retrieving tool for retrieving a core sample of an underground formation includes a coring assembly having a coring bit, a core barrel within a core-receiving chamber, an expandable fluid chamber in fluid communication with the core-receiving chamber, and a valve that selectively seals the core-receiving chamber. The expandable fluid chamber is expandable in response to a pressure differential between the pressure of the core-receiving chamber and an external pressure. With the valve closed, the expandable fluid chamber is in open fluid communication with the core-receiving chamber such that a pressure of the expandable fluid chamber is equalized with the pressure of the core-receiving chamber.

A core retrieving tool for retrieving a core sample of an underground formation includes a coring assembly having a coring bit, a core barrel within a core-receiving chamber, an expandable fluid chamber in fluid communication with the core-receiving chamber, and a valve that selectively seals the core-receiving chamber. The expandable fluid chamber is expandable in response to a pressure differential between the pressure of the core-receiving chamber and an external pressure. With the valve closed, the expandable fluid chamber is in open fluid communication with the core-receiving chamber such that a pressure of the expandable fluid chamber is equalized with the pressure of the core-receiving chamber.

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 long-distance core drilling method suitable for a horizontal geological core drilling rig. (1) An active drill rod is connected to a drill rod, which is connected to a wireline-coring outer-tube drilling tool. (2) A steel-pipe string is connected to a fishing device, and the fishing device is connected to a spearhead on a core tube, which is placed to a designated position through a pipe-feeding mechanism. (3) A washing pump is started. (4) A core drilling is carried out. (5) A core is pulled out. (6) The steel-pipe string and the fishing device are reconnected. (7) The core tube is salvaged. (8) The core tube and drill pipe are replaced. (9) A hole is swept. (10) Steps (1)-(9) are repeated until the hole is drilled to a designated depth. (11) The core tube and the wireline-coring outer-tube drilling tool are recovered.

A long-distance core drilling method suitable for a horizontal geological core drilling rig. (1) An active drill rod is connected to a drill rod, which is connected to a wireline-coring outer-tube drilling tool. (2) A steel-pipe string is connected to a fishing device, and the fishing device is connected to a spearhead on a core tube, which is placed to a designated position through a pipe-feeding mechanism. (3) A washing pump is started. (4) A core drilling is carried out. (5) A core is pulled out. (6) The steel-pipe string and the fishing device are reconnected. (7) The core tube is salvaged. (8) The core tube and drill pipe are replaced. (9) A hole is swept. (10) Steps (1)-(9) are repeated until the hole is drilled to a designated depth. (11) The core tube and the wireline-coring outer-tube drilling tool are recovered.

A system for transferring at least one subterranean core sample under pressure can include a retrieval vessel that collects and houses the at least one subterranean core sample at a sampling pressure at which the at least one subterranean core is collected. The system can also include a linear actuator that couples to the retrieval vessel through a valve in the open position at a first time, where the linear actuator facilitates removal of at least one pressure barrier from the retrieval vessel through the valve at the first time while maintaining the sampling pressure of the at least one subterranean sample. The system can further include a testing vessel that couples to the linear actuator through the valve in the open position at a second time, and a hydraulic device that facilitates pressurizing the testing vessel to the sampling pressure at the second time.