Abstract: An offshore well system for a subsea well includes an internal riser tension device configured to apply tension to an internal riser and an external riser tension device configured to apply tension to an external riser such that the external riser is supported at least partially independent of the internal riser tension device.

Abstract: An offshore well system for a subsea well. The system includes a floating platform, an external riser and an internal riser nested within the external riser. A external riser tension device tensions the external riser. The drilling system also includes a surface wellhead system that includes a wellhead, a collet, and a flange assembly. The wellhead, collet, and flange assembly are assembled to establish a common bore for receiving the top of the internal riser. A gasket located between the top of the internal riser and an inner shoulder of the flange assembly seals between the wellhead system and the top of the internal riser. The surface wellhead system also retains the internal riser in tension with the wellhead, the internal riser extending above the wellhead into the collet.

Abstract: An offshore well drilling system for drilling a subsea well is presented that includes a floating platform, a surface BOP stack, a riser, and a driveable environmental safe guard system. The safe guard system includes an upper wellhead connector, a lower wellhead connector, a blowout preventer with shearing blind rams, and a subsea pressure control system. The subsea pressure control system can be electric, hydraulic, acoustic, or ROV actuated. More importantly, the environmental safeguard system is moveable, and can be driven around using as ROV. The present invention provides swift disconnect and recovery for emergency situations. The subsea environmental safe guard system is also much lighter in weight than traditional subsea stacks.

Abstract: An offshore well system for a subsea well. The system includes a floating platform, an external riser and an internal riser nested within the external riser. A external riser tension device tensions the external riser. The drilling system also includes a surface wellhead system that includes a wellhead, a collet, and a flange assembly. The wellhead, collet, and flange assembly are assembled to establish a common bore for receiving the top of the internal riser. A gasket located between the top of the internal riser and an inner shoulder of the flange assembly seals between the wellhead system and the top of the internal riser. The surface wellhead system also retains the internal riser in tension with the wellhead, the internal riser extending above the wellhead into the collet.

Abstract: An offshore well system for a subsea well. The system includes a floating platform, an external riser and an internal riser nested within the external riser. A external riser tension device tensions the external riser. The drilling system also includes a surface wellhead system that includes a wellhead, a collet, and a flange assembly. The wellhead, collet, and flange assembly are assembled to establish a common bore for receiving the top of the internal riser. A gasket located between the top of the internal riser and an inner shoulder of the flange assembly seals between the wellhead system and the top of the internal riser. The surface wellhead system also retains the internal riser in tension with the wellhead, the internal riser extending above the wellhead into the collet.

Abstract: An offshore well system for a subsea well includes an internal riser tension device configured to apply tension to an internal riser and an external riser tension device configured to apply tension to an external riser such that the external riser is supported at least partially independent of the internal riser tension device.

Abstract: An offshore well drilling system for drilling a subsea well is presented that includes a floating platform, a surface BOP stack, a riser, and a driveable environmental safe guard system. The safe guard system includes an upper wellhead connector, a lower wellhead connector, a blowout preventer with shearing blind rams, and a subsea pressure control system. The subsea pressure control system can be electric, hydraulic, acoustic, or ROV actuated. More importantly, the environmental safeguard system is moveable, and can be driven around using as ROV. The present invention provides swift disconnect and recovery for emergency situations. The subsea environmental safe guard system is also much lighter in weight than traditional subsea stacks.

Abstract: An offshore well system for a subsea well. The system includes a floating platform, an external riser and an internal riser nested within the external riser. A external riser tension device tensions the external riser. The drilling system also includes a surface wellhead system that includes a wellhead, a collet, and a flange assembly. The wellhead, collet, and flange assembly are assembled to establish a common bore for receiving the top of the internal riser. A gasket located between the top of the internal riser and an inner shoulder of the flange assembly seals between the wellhead system and the top of the internal riser. The surface wellhead system also retains the internal riser in tension with the wellhead, the internal riser extending above the wellhead into the collet.

Abstract: An offshore well drilling system for drilling a subsea well is presented that includes a floating platform, a surface BOP stack, a riser, and a driveable environmental safe guard system. The safe guard system includes an upper wellhead connector, a lower wellhead connector, a blowout preventer with shearing blind rams, and a subsea pressure control system. The subsea pressure control system can be electric, hydraulic, acoustic, or ROV actuated. More importantly, the environmental safeguard system is moveable, and can be driven around using as ROV. The present invention provides swift disconnect and recovery for emergency situations. The subsea environmental safe guard system is also much lighter in weight than traditional subsea stacks.

Abstract: An offshore well drilling system for drilling a subsea well, including a floating platform, an external riser extending from the subsea well, and an internal riser extending from the subsea well to the platform. The internal riser is nested within the external riser. The system also includes an external riser tension device to apply tension to the external riser. The system also includes an internal riser tension device, separate from the external riser tension device, to apply tension to the internal riser.

Abstract: An offshore well system for a subsea well. The system includes a floating platform, an external riser and an internal riser nested within the external riser. A external riser tension device tensions the external riser. The drilling system also includes a surface wellhead system that includes a wellhead, a collet, and a flange assembly. The wellhead, collet, and flange assembly are assembled to establish a common bore for receiving the top of the internal riser. A gasket located between the top of the internal riser and an inner shoulder of the flange assembly seals between the wellhead system and the top of the internal riser. The surface wellhead system also retains the internal riser in tension with the wellhead, the internal riser extending above the wellhead into the collet.

Abstract: An offshore well system for a subsea well. The system includes a floating platform, an external riser and an internal riser nested within the external riser. A external riser tension device tensions the external riser. The drilling system also includes a surface wellhead system that includes a wellhead, a collet, and a flange assembly. The wellhead, collet, and flange assembly are assembled to establish a common bore for receiving the top of the internal riser. A gasket located between the top of the internal riser and an inner shoulder of the flange assembly seals between the wellhead system and the top of the internal riser. The surface wellhead system also retains the internal riser in tension with the wellhead, the internal riser extending above the wellhead into the collet.

Abstract: An offshore well system for a subsea well. The system includes a floating platform, an external riser and an internal riser nested within the external riser. A external riser tension device tensions the external riser. The drilling system also includes a surface wellhead system that includes a wellhead, a collet, and a flange assembly. The wellhead, collet, and flange assembly are assembled to establish a common bore for receiving the top of the internal riser. A gasket located between the top of the internal riser and an inner shoulder of the flange assembly seals between the wellhead system and the top of the internal riser. The surface wellhead system also retains the internal riser in tension with the wellhead, the internal riser extending above the wellhead into the collet.

Abstract: An offshore well drilling system for drilling a subsea well is presented that includes a floating platform, a surface BOP stack, a riser, and a driveable environmental safe guard system. The safe guard system includes an upper wellhead connector, a lower wellhead connector, a blowout preventer with shearing blind rams, and a subsea pressure control system. The subsea pressure control system can be electric, hydraulic, acoustic, or ROV actuated. More importantly, the environmental safeguard system is moveable, and can be driven around using as ROV. The present invention provides swift disconnect and recovery for emergency situations. The subsea environmental safe guard system is also much lighter in weight than traditional subsea stacks.