A fluid separating device comprises: a cylinder; a plurality of separators disposed around a cylinder; a first elastic piece disposed between one of the separators and the cylinder and applying an elastic force to the separator outwardly in the radial direction of the cylinder; a first guiding device passing through the cylinder axially and configured to reciprocate between an expanded position and a contracted position in the axial direction of the cylinder; a second guiding device penetrating the cylinder, connected to the separator at one end, and slidably fitted with the first guiding device at the other end via a fitting surface. The fluid separating device eliminates the friction between the separator and the inner wall of the wellhole when descending, therefore descending to the bottom of the well quickly.

Measurement of the inclination and azimuthal direction of a borehole extending beneath an obstacle, such as a body of water, which utilizes magnetic and gravity sensors at the drill bit of a borehole being drilled. Embodiments of the present invention determine and remove remanent field components and the effects of ferromagnetic permeability prior to and during drilling of the borehole

A system and method of directionally steering a bottom hole assembly (“BHA”) by receiving data indicative of a directional trend of the BHA and a projection to bit depth; determining a location of the BHA based on the received data; comparing the location of the BHA to a planned drilling path to identify an amount of deviation; automatically creating a modified drilling path based on the amount of deviation and a predicted trend of a downhole parameter; detecting a trend of the downhole parameter while drilling along the modified drilling path; and automatically creating a further modified drilling path when the trend of the downhole parameter is a reversal of the predicted trend of the downhole parameter. The predicted trend of the downhole parameter is an increase of a d-exponent factor or a d-exponent-corrected factor with an increase in depth.

A method and system for steering the direction of propagation of a flexible liner everting under a driving fluid pressure. There is provided a method for controlling and guiding directionally the eversion of the flexible liner into a borehole that penetrates a subsurface (e.g., subterranean) void with a diameter substantially exceeding the nominal diameter of the borehole. Further, liner propagation by eversion can be controlled outside of a borehole and when unconstrained by a borehole, such as on or beneath the surface of a body of water.

A method for steering a downhole tool includes receiving an electromagnetic (EM) signal from the downhole tool. The downhole tool is in a wellbore in a formation. The EM signal comprises a gap voltage and a gap current that are measured across a gap sub in the downhole tool. The method also includes determining a gap impedance based at least partially upon the gap voltage and the gap current. The method also includes determining a first formation resistivity at a first location in the wellbore based at least partially upon the gap impedance. The method also includes steering the downhole tool based at least partially upon the first formation resistivity.

A method for steering a downhole tool includes receiving an electromagnetic (EM) signal from the downhole tool. The downhole tool is in a wellbore in a formation. The EM signal comprises a gap voltage and a gap current that are measured across a gap sub in the downhole tool. The method also includes determining a gap impedance based at least partially upon the gap voltage and the gap current. The method also includes determining a first formation resistivity at a first location in the wellbore based at least partially upon the gap impedance. The method also includes steering the downhole tool based at least partially upon the first formation resistivity.

A system can generate and output boundary lines for controlling a drilling operation. The system can receive data, including an offset well surveys, measuring instrument information, and a well casing diameter, about offset wells in a subterranean formation. The system can determine reference well values. The system can generate boundary lines for the offset wells based on the received data and the calculated reference well values. The system can adjust the boundary lines, and can output the adjusted boundary lines for controlling a drilling operation.

A system can generate and output boundary lines for controlling a drilling operation. The system can receive data, including an offset well surveys, measuring instrument information, and a well casing diameter, about offset wells in a subterranean formation. The system can determine reference well values. The system can generate boundary lines for the offset wells based on the received data and the calculated reference well values. The system can adjust the boundary lines, and can output the adjusted boundary lines for controlling a drilling operation.

Disclosed is a downhole tool and method suitable for geosteering within a lateral formation. The downhole tool includes a gamma sensor for monitoring gamma radiation within the lateral formation. The method provides for monitoring of the location of the drill bit or a RSS within a borehole and correcting the angle of inclination to maintain the drill bit or RSS within the target zone of the lateral formation.

Disclosed is a downhole tool and method suitable for geosteering within a lateral formation. The downhole tool includes a gamma sensor for monitoring gamma radiation within the lateral formation. The method provides for monitoring of the location of the drill bit or a RSS within a borehole and correcting the angle of inclination to maintain the drill bit or RSS within the target zone of the lateral formation.