Offshore universal riser system
First Claim
1. A method of pressure testing a riser string, the method comprising:
- installing a valve module into an internal longitudinal flow passage extending through the riser string between a blowout preventer stack and a diverter;
closing the valve module to thereby prevent fluid flow through the flow passage;
securing a tubular string within the riser string by an anchoring device in engagement with the riser string; and
applying a pressure differential across the closed valve module via the tubular string, thereby pressure testing at least a portion of the riser string.
1 Assignment
0 Petitions
Accused Products
Abstract
An offshore universal riser system may include a valve module which selectively permits and prevents fluid flow through a flow passage extending longitudinally through a riser string. An anchoring device may releasably secure the valve module in the passage. A method of constructing a riser system may include the steps of installing the valve module in the passage, and installing at least one annular seal module in the passage. The annular seal module may prevent fluid flow through an annular space between the riser string and a tubular string positioned in the passage. Drilling methods may include injecting relatively low density fluid compositions into the annular space, and selectively varying a restriction to flow through a subsea choke in a drilling fluid return line. The riser string, including housings for the various modules and external control systems, may be dimensioned for installation through a rotary table.
209 Citations
10 Claims
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1. A method of pressure testing a riser string, the method comprising:
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installing a valve module into an internal longitudinal flow passage extending through the riser string between a blowout preventer stack and a diverter; closing the valve module to thereby prevent fluid flow through the flow passage; securing a tubular string within the riser string by an anchoring device in engagement with the riser string; and applying a pressure differential across the closed valve module via the tubular string, thereby pressure testing at least a portion of the riser string. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
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Specification