Riserless mud return system
OwnerJames F. Arnoldinventor
Life of this patent
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Abstract
A system and method are disclosed which eliminates the use of a riser pipe in underwater drilling operations. The system includes a mud sump connectable to the top of a submerged wellhead and has a bottom with a mud inlet provided therein and an upwardly extending wall cooperating with the bottom to support a quantity of mud, the sump restricting the water to contact with only the upper surface of the mud as the mud passes upwardly through the mud inlet in the bottom. A hose, separate from the drill string, is used to carry mud to the surface of the water. A pumping means is used to pump mud through the hose in response to the quantity of mud supported within the sump to thereby return the mud to the surface of the water without the use of a riser pipe.
Claims18
A system used in underwater drilling operations for returning drilling mud to the surface of the water, comprising a mud sump connectable to the top of a submerged wellhead and having (i) a bottom with a mud inlet provided therein, and (ii) an upwardly extending side coacting with the bottom to support a quantity of drilling mud, and means for placing the water in continuous contact with the upper surface of the mud as the mud passes upwardly through the mud inlet in the bottom during drilling operations, a hose separate from the drill string for carrying drilling mud to the surface of the water, and means for mechanically pumping the mud through the hose in response to the quantity of mud supported within the sump to thereby return the mud to the surface of the water without the use of a riser pipe.
A method of eliminating a riser pipe in underwater drilling operations, comprising the steps of positioning a mud sump having a mud inlet in the bottom over a bore of a submerged wellhead, flowing drilling mud down through a drill string extending through the mud inlet in the bottom of the mud sump into the bore, displacing water from the sump with drilling mud received through the mud inlet in the bottom of the container, supporting a quantity of the received drilling mud in the sump, causing the upper surface of the received mud to be continuously in contact with the water during drilling operations, and mechanically pumping mud from the mud sump through a hose separate from a drill string to the surface of the water to thereby return drilling mud to the surface of the water without using a riser pipe.
A system used in underwater drilling operations for returning drilling mud to the surface of the water, comprising a mud sump connectable to the top of a submerged wellhead having a bottom with a mud inlet provided therein and an upwardly extending side coacting with the bottom to support a quantity of drilling mud and restrict the water to contact with only the upper surface of the mud as the mud passes upwardly through the mud inlet in the bottom, a hose separate from the drill string for carrying drilling mud to the surface of the water, means for pumping the mud through the hose, and a level sensor provided in the sump to activate and deactivate the mud pumping means in response to the quantity of mud supported in the container to thereby return the mud to the surface of the water without the use of a riser pipe.
Dependencies are inferred from the claim text.