Method and device for drilling for oil or gas
DC CAFCFirst Claim
1. A method for drilling for oil or gas in an underwater bed by means of a drilling rig disposed on a floating drilling platform or on the underwater bed and having at least one drilling derrick, the method comprising the following steps:
- a. assembling a drill string and drilling a borehole in the underwater bed with the drill string by means of the drilling derrick;
b. removing the drill string from the borehole;
c. assembling and placing a casing string in the borehole;
d. repeating steps a., b. and c. at least once for boreholes and casing strings of ever decreasing diameter;
e. assembling a riser string, and placing a riser string after placing of one of the casing strings;
the method further comprising the step of, prior to the placing of a casing string, the placing of a riser string or the drilling of a hole, pre-assembling one or more parts of the casing string, the riser string or the drill string on the drilling rig at one or more pre-assembly points which are in a position which is different from the position of the at least one drilling derrick; and
conveying to the drilling derrick each part of the casing string, riser string or drill string from the pre-assembly points to means for assembling the casing string, riser string or drill string and placing the casing string in the borehole, placing the riser string in the borehole or drilling a borehole.
3 Assignments
Litigations
0 Petitions
Accused Products
Abstract
In a method and device for drilling for oil or gas in an underwater bed by means of a drilling rig with a drilling derrick disposed on a floating drilling platform or on an underwater bed, prior to the placing of a casing string, the placing of a riser string or the drilling of a hole, one or more parts of the casing string, the riser string or the drill string are pre-assembled on the drilling rig at one or more pre-assembly points which are in a position which is different from the position of the drilling derrick.
45 Citations
24 Claims
-
1. A method for drilling for oil or gas in an underwater bed by means of a drilling rig disposed on a floating drilling platform or on the underwater bed and having at least one drilling derrick, the method comprising the following steps:
-
a. assembling a drill string and drilling a borehole in the underwater bed with the drill string by means of the drilling derrick; b. removing the drill string from the borehole; c. assembling and placing a casing string in the borehole; d. repeating steps a., b. and c. at least once for boreholes and casing strings of ever decreasing diameter; e. assembling a riser string, and placing a riser string after placing of one of the casing strings; the method further comprising the step of, prior to the placing of a casing string, the placing of a riser string or the drilling of a hole, pre-assembling one or more parts of the casing string, the riser string or the drill string on the drilling rig at one or more pre-assembly points which are in a position which is different from the position of the at least one drilling derrick; and conveying to the drilling derrick each part of the casing string, riser string or drill string from the pre-assembly points to means for assembling the casing string, riser string or drill string and placing the casing string in the borehole, placing the riser string in the borehole or drilling a borehole. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
-
-
15. A drilling rig for drilling for oil or gas in an underwater bed, disposed on a floating drilling platform or on the underwater bed, comprising;
-
at least one drilling derrick; means on the drilling derrick for assembling a drill string and drilling a borehole in the bed; means for assembling and placing a casing string in the borehole; and means for assembling and placing a riser string on the borehole; the drilling rig further comprising; one or more pre-assembly installations which are situated in a place which is different from that of the at least one drilling derrick, for the pre-assembly of one or more parts of a casing, riser or drill string; and conveyor means for conveying to the drilling derrick each part of a casing, riser or drill string from each pre-assembly installation to the means for assembling the casing, riser or drill string and placing the casing string in the borehole, placing the riser string on the borehole or drilling a borehole. - View Dependent Claims (16, 17, 18, 19, 20, 21, 22, 23, 24)
-
Specification