Method for excavating mud line cellar for subsea well drilling
AssigneeNoble Drilling Services Inc.
InventorsHans H. J. Deul, Patrick O'Neill, Matthew Sibrel, Robert van Kuilenburg
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Abstract
A method for excavating a well cellar includes lowering an excavating apparatus having a cellar liner therein to a bottom of a body of water. The well cellar is excavated while contemporaneously lowering the cellar liner into the well cellar until a top of the cellar liner is substantially level with the bottom of the body of water. A pilot well is excavated below a bottom of the cellar. A well head support pipe is inserted into the pilot well. The bottom of the well cellar and a top of the cellar liner are covered.
Claims11
A method for excavating a well cellar, comprising:
- lowering an excavating apparatus having a cellar liner therein to a bottom of a body of water, the excavating apparatus comprising pads mounted to articulated arms, the arms extendable and retractable to selectively lock the excavating apparatus in place inside the cellar liner, a first motor coupled to a drill bit, the first motor mounted to the excavating apparatus by a pivoting element operable so that an angle of the first motor with respect to a longitudinal axis of the excavating apparatus is controllable during use, means to move the excavating apparatus upwardly and downwardly, and a second motor attached to excavating apparatus enable rotation of the first motor about the longitudinal axis;
- excavating the well cellar by operating the excavating apparatus, while contemporaneously lowering the cellar liner into the well cellar until a top of the cellar liner is substantially level with the bottom of the body of water;
- excavating a pilot well below a bottom of the cellar using the excavating apparatus;
- and
- inserting a well head support pipe into the pilot well.
Dependencies are inferred from the claim text.