| Patent application number | Description | Published |
|---|
| 20090095463 | CIRCULATION CONTROL VALVE AND ASSOCIATED METHOD - A circulation control valve includes an opening between the valve exterior and an interior passage, an internal closure device for permitting and preventing flow through the opening, a valve device initially preventing flow through the opening, and an internal chamber. The valve device opens upon application of a pressure differential between the passage and the exterior to thereby permit communication through the opening, and the closure device displaces upon a second pressure differential between the passage and the internal chamber to thereby prevent communication through the opening. Another valve includes first and second valve devices. Communication through the opening is permitted upon application of the first pressure differential to the first device, thereby unbalancing a first piston, and fluid communication through the opening is prevented upon application of the second pressure differential to the second device, thereby unbalancing a second piston having a greater piston area than the first piston. | 04-16-2009 |
| 20090095486 | CIRCULATION CONTROL VALVE AND ASSOCIATED METHOD - A circulation control valve. A method of controlling circulation flow between an interior flow passage of a tubular string and an annulus external to the tubular string in a subterranean well includes the steps of: interconnecting a valve in the tubular string, the valve including at least one opening for providing fluid communication between the interior flow passage and the annulus; applying an increased pressure to the interior flow passage while fluid communication through the opening between the interior flow passage and the annulus is prevented, thereby permitting fluid communication through the opening between the interior flow passage and the annulus; and then applying another increased pressure to the interior flow passage while fluid communication through the opening between the interior flow passage and the annulus is permitted, thereby preventing fluid communication through the opening between the interior flow passage and the annulus. | 04-16-2009 |
| 20100051260 | Fluid Isolating Pressure Equalization in Subterranean Well Tools - A fluid isolating pressure equalization in a subterranean well. A well system includes a well tool including a chamber therein containing an electrical assembly in a dielectric fluid, and a pressure equalization apparatus including a flowpath having opposite ends. One end is connected to the chamber, and the other end is connected to a source of another fluid. The flowpath extends alternately upward and downward between the opposite ends. A pressure equalization apparatus for use with a well tool in a subterranean well includes multiple spiral wraps of a tube. A flowpath in the tube extends in opposite directions in respective successive wraps of the tube. | 03-04-2010 |
| 20110042099 | Remote Actuated Downhole Pressure Barrier and Method for Use of Same - A downhole pressure barrier ( | 02-24-2011 |
| 20110079393 | CIRCULATION CONTROL VALVE AND ASSOCIATED METHOD - A circulation control valve. A method of controlling circulation flow between an interior flow passage of a tubular string and an annulus external to the tubular string in a subterranean well includes the steps of: interconnecting a valve in the tubular string, the valve including at least one opening for providing fluid communication between the interior flow passage and the annulus; applying an increased pressure to the interior flow passage while fluid communication through the opening between the interior flow passage and the annulus is prevented, thereby permitting fluid communication through the opening between the interior flow passage and the annulus; and then applying another increased pressure to the interior flow passage while fluid communication through the opening between the interior flow passage and the annulus is permitted, thereby preventing fluid communication through the opening between the interior flow passage and the annulus. | 04-07-2011 |
| 20110240299 | SUBTERRANEAN WELL VALVE ACTIVATED WITH DIFFERENTIAL PRESSURE - A method of actuating a valve in a well can include storing energy as a result of a differential pressure across a closed closure device of the valve, and releasing at least a portion of the stored energy while opening the closure device. A valve for use in a well can include a closure device, a biasing device, and an actuator which stores energy in the biasing device in response to a pressure differential across the closure device. A well system can include a tubular string, and a valve which controls fluid flow through the tubular string. The valve may include a closure device and an actuator which actuates the valve at least partially in response to a pressure differential across the closure device. | 10-06-2011 |
