Patent · US Active

Systems and methods for subsea drilling

US8640778B2 · kind B2 · utility

12Cited by

11References

36Claims

0Family size

Assignee

Ocean Riser Systems AS · NO

Inventor

Børre Fossli · Oslo, NO

Key dates

Filing date	Apr 6, 2009
Grant date	Feb 4, 2014
Priority date	—
Expiry date	Apr 6, 2029

Classification

Technology area (CPC E)Fixed Constructions
CPC primaryE21B43/36
WIPO fieldCivil engineering
WIPO sectorOther fields

Abstract

A subsea drilling method and system for controlling the drilling fluid pressure, where drilling fluid is pumped down into the borehole through a drill string and returned back through the annulus between the drill string and the well bore. The drilling fluid pressure is controlled by draining drilling fluid out of the drilling riser (8) or BOP (6) at a level between the seabed and the sea water in order to adjust the hydrostatic head of drilling fluid. The drained drilling fluid and gas is separated in a subsea separator (28) where the gas is vented to surface through a vent line (39), and the fluid is pumped to surface via pump (40).

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.