초록 ▼

Devices and methods for methods for cleaning of excess cement from a production assembly as well as from the annulus surrounding the production assembly. A hydrostatic closed circulation valve (HCCV) assembly is described that is primarily actuatable between open and closed positions by varying hydr

Devices and methods for methods for cleaning of excess cement from a production assembly as well as from the annulus surrounding the production assembly. A hydrostatic closed circulation valve (HCCV) assembly is described that is primarily actuatable between open and closed positions by varying hydraulic pressure in the flowbore of the production assembly. The valve assembly is useful for selectively circulating working fluid into the annulus from the flowbore of the production assembly.

대표청구항 ▼

What is claimed is: 1. A valve assembly for selectively providing fluid communication with a wellbore annulus comprising: a completion string; a tubular inner mandrel defining a flowbore within and having first and second ends disposed in the completion string; a fluid flow port disposed within the

What is claimed is: 1. A valve assembly for selectively providing fluid communication with a wellbore annulus comprising: a completion string; a tubular inner mandrel defining a flowbore within and having first and second ends disposed in the completion string; a fluid flow port disposed within the inner mandrel to permit fluid communication between the flowbore and an annulus area radially exterior of the inner mandrel after the completion string has been at least partially cemented in the wellbore; an outer sleeve radially surrounding the inner mandrel, the outer sleeve being moveable with respect to the inner mandrel between a substantially open position, wherein the outer sleeve substantially does not block the fluid flaw port, and a substantially closed position, wherein the outer sleeve substantially does block the fluid flow port; and a frangible rupture member disposed within the fluid flow port, the rupture member being rupturable in response to a first level of fluid pressure within the flowbore. 2. The valve assembly of claim 1 further comprising an inner sleeve contained within the flowbore of the inner mandrel, the inner sleeve being moveable between a substantially open position, wherein the inner sleeve substantially does not block the fluid flow port, and a substantially closed position, wherein the inner sleeve substantially does block the fluid flow port. 3. The valve assembly of claim 1 wherein the outer sleeve presents a pressure-receiving area so that an increase of fluid pressure upon the pressure receiving area moves the outer sleeve from the substantially open position to the substantially closed position. 4. The valve assembly of claim 2 wherein the inner sleeve presents a profile for selective engagement by a shifter in order to axially move the inner sleeve from the substantially open position to the substantially closed position. 5. The valve assembly of claim 1 wherein the outer sleeve presents an axially-located pressure receiving area, and the outer sleeve is moveable between the substantially open and substantially closed positions in response to a second level of fluid pressure upon the pressure receiving area. 6. The valve assembly of claim 5 wherein the outer sleeve is selectively secured to the inner mandrel by a frangible pin that is broken upon application of the second level of fluid pressure to the pressure-receiving area. 7. A system for cleaning excess cement from a completion assembly in conjunction with a cementing operation and to prepare the completion assembly for production of hydrocarbons from a formation, the system comprising: a completion string; a flowbore defined along the length of the completion string along which cement or hydrocarbon fluids may be flowed; a valve assembly incorporated into the completion string for providing selective fluid communication between the flowbore and an annular space surrounding the completion assembly after the completion string has been at least partially cemented in the wellbore; and a flow device selectively closing a lower end of the flowbore from fluid flow. 8. The system of claim 7 wherein the flow device comprises a plug member that is landed in a complimentary landing seat within the flowbore. 9. The system of claim 8 wherein the plug member comprises a wiper plug having at least one wiper disc for wiping of excess cement from the completion string. 10. The system of claim 7 wherein a first level of fluid pressure within the flowbore selectively opens the valve assembly. 11. The system of claim 7 wherein a second level of fluid pressure within the flowbore and the annular space closes the valve assembly. 12. The system of claim 7 wherein the valve assembly is substantially closable by a shifting tool. 13. The system of claim 7 wherein the valve assembly includes a fluid flow opening that provides for fluid communication between the flowbore and the annular space, the fluid flow opening being initially closed by a frangible rupture member that will rupture upon application of a first fluid pressure level to the valve assembly. 14. The system of claim 7 wherein the valve assembly comprises: an inner mandrel containing a lateral fluid flow opening; and a first sleeve that is moveable with respect the inner mandrel to selectively open and close the fluid flow opening to fluid flow therethrough. 15. The system of claim 14 wherein the first sleeve is moveable in response to fluid pressure that is applied to the valve assembly. 16. The system of claim 14 wherein the valve assembly further comprises a second sleeve that is moveable with respect the inner mandrel to selectively open and close the fluid flow opening to fluid flow therethrough. 17. The system of claim 16 wherein the second sleeve is manually actuatable by means of a shifting tool. 18. A method for operating a valve assembly having an axial flowbore and incorporated within a wellbore completion system, the method comprising: at least partially cementing a completion string in the wellbore; applying a first level of fluid pressure to the valve assembly disposed along the completion string to open a fluid flow port in the valve assembly; circulating well working fluid into the flowbore, through the fluid flow port, and into an annular space radially surrounding the valve assembly; and applying a second level of fluid pressure to the valve assembly to close the fluid flow port. 19. The method of claim 18 wherein the step of applying a first level of fluid pressure to open the fluid flow port further comprises rupturing a frangible rupture member. 20. The method of claim 18 wherein the step of applying a second level of fluid pressure to close the fluid flow port further comprises moving a sleeve of the valve assembly. 21. The method of claim 18 further comprising manually closing the fluid port in the event that the second level of fluid pressure fails to close the fluid flow port.