The invention relates to reamers used in downhole oil well drilling operations, particularly in reaming while drilling applications. Presented is a reamer having an interior channel which runs along an elongate axis of the entire body of the reamer, wherein there are openings along both ends of the reamer, exposing the interior channel. Additionally presented in the reamer are a plurality of paths extending parallel to the interior channel along the exterior of the body of the reamer, and running in a helical pattern along the entirety of the exterior of the body of the reamer. Disposed within the helical paths are a plurality of cutting inserts, which cutting inserts are enabled to provides a uniform cutting surface against a well bore, which preferably improves cutting action and reduces strain on the reamer.

The present invention refers to a method of drilling a marine wellbore with fluid reverse circulation without using drilling riser tubulars. In reverse circulation drilling, the fluid return with gravels occurs inside the drill string (17) and the injection of clean fluid is done through the annular of the well, so that, having a rotating head over the BOP (19), or inside it, the use of riser tubulars as a flow line for the fluid return with gravels is disposed, using instead the drill string (17). For the kill and choke lines, as well as for fluid injection, rigid or flexible lines can be used, eliminating the need to use drilling risers, thus releasing large load capacity and space on the probe. The method of this invention also eliminates the need for large volumes of fluid to fill entire riser tubulars. The entire operation can be done without the need for subsea pumps or concentric columns. Additionally, the invention makes the operation of lowering the drilling riser tubulars unnecessary, which lasts for days and has a high cost. Finally, for dual activity probes, the arrangement allows the use of the two towers even after connecting the BOP (19), something that is not possible with the use of drilling riser tubulars. Therefore, operations such as mounting and lowering the casing in the water depth can be carried out in parallel with the drilling of the phase, allowing a significant additional gain of time.

The present invention refers to a method of drilling a marine wellbore with fluid reverse circulation without using drilling riser tubulars. In reverse circulation drilling, the fluid return with gravels occurs inside the drill string (17) and the injection of clean fluid is done through the annular of the well, so that, having a rotating head over the BOP (19), or inside it, the use of riser tubulars as a flow line for the fluid return with gravels is disposed, using instead the drill string (17). For the kill and choke lines, as well as for fluid injection, rigid or flexible lines can be used, eliminating the need to use drilling risers, thus releasing large load capacity and space on the probe. The method of this invention also eliminates the need for large volumes of fluid to fill entire riser tubulars. The entire operation can be done without the need for subsea pumps or concentric columns. Additionally, the invention makes the operation of lowering the drilling riser tubulars unnecessary, which lasts for days and has a high cost. Finally, for dual activity probes, the arrangement allows the use of the two towers even after connecting the BOP (19), something that is not possible with the use of drilling riser tubulars. Therefore, operations such as mounting and lowering the casing in the water depth can be carried out in parallel with the drilling of the phase, allowing a significant additional gain of time.

It is disclosed a satellite well structure (300) and method for expanding a subsea satellite well system. The subsea satellite well structure (300) comprising:—a seabed-based foundation (330) supporting a subsea wellhead (340);—a first landing position (310) configured to receive a Christmas tree module (200) for interfacing the subsea wellhead (340);—a second landing position (320) configured to receive a subsea connection module (100) for connecting the Christmas tree module (200) to a hydrocarbon fluid export flowline; and—a plurality of Christmas tree guide posts configured to support the installation of the Christmas tree module; wherein the first landing position has a landing envelope defined by the plurality of Christmas tree guide posts, and wherein the second landing positions is arranged offset the landing envelope of the first landing position, (allowing:—the subsea connection module (100) to be landed on and retrieved from the seabed-based well structure (300) with the Christmas tree module (200) landed in the first landing position (310); and—the Christmas tree module (200) to be landed on and retrieved from the seabed-based well structure (300) with the subsea connection module (100) landed in the second landing position (320).

A drill device comprising: a pile configured such that same descends to a seafloor surface through a mooring installation device provided in a ship, and a part of the body thereof is fixed in an area of the seafloor surface as the upper surface thereof is pressurized in the vertical direction; a driving pipe configured such that same descends to the seafloor surface through a through-hole formed in the pile, the body thereof is inserted into a seafloor foundation, and same is recovered through the through-hole after excavation is completed; a chain, one end of which is fixed to one side of the pile, and the other end of which is introduced through the through-hole such that same is inserted into the seafloor foundation together with the driving pipe; and a drill bit unit.

A deepwater subsea coiled tubing drilling rig includes a lifting rack having an upper rack and a lower rack which are sleeved with each other and connected by a lifting device. A working space is enclosed by the upper rack and the lower rack, and an underwater connecting and disconnecting tool is installed in the working space; the working space is transformed between a high-position large-space state for connecting and disconnecting through the tool and a low-position small-space state for the drilling process, along with the up-down movement of the upper rack. The upper rack is provided with an underwater coiled tubing system used for lowering and lifting a downhole tool combination, and the lower rack is provided with a wellhead device.

A deepwater subsea coiled tubing drilling rig includes a lifting rack having an upper rack and a lower rack which are sleeved with each other and connected by a lifting device. A working space is enclosed by the upper rack and the lower rack, and an underwater connecting and disconnecting tool is installed in the working space; the working space is transformed between a high-position large-space state for connecting and disconnecting through the tool and a low-position small-space state for the drilling process, along with the up-down movement of the upper rack. The upper rack is provided with an underwater coiled tubing system used for lowering and lifting a downhole tool combination, and the lower rack is provided with a wellhead device.

A system for preventing annular pressure buildup comprising: a wellbore; two or more annuli located within the wellbore; a piston assembly located adjacent to a wellhead of the wellbore; and a pipe system that connects the two or more annuli in parallel to the piston assembly, wherein when the amount of pressure in the pipe system exceeds a predetermined amount, then a piston of the piston assembly moves whereby the movement reduces the amount of pressure in the two or more annuli.

A system for preventing annular pressure buildup comprising: a wellbore; two or more annuli located within the wellbore; a piston assembly located adjacent to a wellhead of the wellbore; and a pipe system that connects the two or more annuli in parallel to the piston assembly, wherein when the amount of pressure in the pipe system exceeds a predetermined amount, then a piston of the piston assembly moves whereby the movement reduces the amount of pressure in the two or more annuli.

The present invention refers to a method of drilling a marine wellbore with fluid reverse circulation without using drilling riser tubulars. In reverse circulation drilling, the fluid return with gravels occurs inside the drill string (17) and the injection of clean fluid is done through the annular of the well, so that, having a rotating head over the BOP (19), or inside it, the use of riser tubulars as a flow line for the fluid return with gravels is disposed, using instead the drill string (17).

For the kill and choke lines, as well as for fluid injection, rigid or flexible lines can be used, eliminating the need to use drilling risers, thus releasing large load capacity and space on the probe. The method of this invention also eliminates the need for large volumes of fluid to fill entire riser tubulars. The entire operation can be done without the need for subsea pumps or concentric columns. Additionally, the invention makes the operation of lowering the drilling riser tubulars unnecessary, which lasts for days and has a high cost. Finally, for dual activity probes, the arrangement allows the use of the two towers even after connecting the BOP (19), something that is not possible with the use of drilling riser tubulars. Therefore, operations such as mounting and lowering the casing in the water depth can be carried out in parallel with the drilling of the phase, allowing a significant additional gain of time.