The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 16, 2010
Filed:
Nov. 24, 2004
Applicant:
Roger Stave, Knarrevik, NO;
Inventor:
Roger Stave, Knarrevik, NO;
Assignee:
AGR Subsea AS, Straume, NO;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21B 29/12 (2006.01); E21B 1/12 (2006.01);
U.S. Cl.
CPC ...
Abstract
A method of reducing drilling fluid pressure during subsea drilling, where drilling fluid is pumped down into a borehole and then flows back to a drilling rig via the lined and/or unlined sections of the borehole and a liner, wherein the drilling fluid pressure is controlled by pumping drilling fluid out of the liner at the seabed, and where the liner annulus above the drilling fluid is filled with a riser fluid having a density different from that of the drilling fluid.