Title:
デュアルライザアセンブリ、深海掘削方法および装置
Document Type and Number:
Japanese Patent JP4039798
Kind Code:
B2
Abstract:
The invention is designed to conduct drilling procedures between the deck of a dual-activity drilling assembly above the surface of the body of water and a single well location in the bed of the body of water. The dual riser assembly is operable to be connected to a single BOP of a well hole and includes plural riser segments. A first riser segment has a longitudinal axis substantially coincident with the longitudinal axes of a first riser from the surface drilling assembly and the well hole. A second riser segment extends from the dual riser assembly at an acute angle with respect to the first riser segment and is in selective communication with the first riser segment. Each riser segment of the subject invention is equipped with a valve, or blind rams, that may be independently opened or closed to respectively connect or seal off the riser above the well hole. The isolating properties of these valves accommodate the method of running simultaneous drillstrings in a non-active riser to a point above the valves without disrupting any activity being performed through the corpus of the assembly and well hole from the active riser.
Inventors:
Robert Jay Scott
Application Number:
JP2000305559A
Publication Date:
January 30, 2008
Filing Date:
October 04, 2000
Export Citation:
Assignee:
Transocean Offshore Deep Water Drilling Incorporated
International Classes:
E21B33/038; E21B43/01; E21B17/01; E21B43/00
Domestic Patent References:
| JP10508270A | ||||
| JP49095802A |
Foreign References:
| US4819730 | ||||
| US3472317 |
Attorney, Agent or Firm:
Akihiro Ryuka