Downhole system and method for fastening upper and lower casings via expandable metal sleeve

1. A downhole system for deployment in a borehole, the downhole system comprising:

an upper casing having an inside surface; and

a lower casing having a first annular barrier connected to an outer surface of the lower casing, the first annular barrier including a first expandable metal sleeve, the first expandable metal sleeve being expandable upon the application of pressurized fluid to engage the inside surface of the upper casing, to fasten the lower casing to the upper casing, the lower casing configured to allow fluid to flow directly through the lower casing and into the first annular barrier, the first annular barrier being positioned between the outer surface of the lower casing and the inside surface of the upper casing after the first expandable metal sleeve has been expanded, the outer surface of the lower casing being radially spaced from the inside surface of the upper casing after the first expandable metal sleeve has been expanded, wherein the inside surface of the upper casing is located proximate a downhole end of the upper casing, and the first annular barrier of the lower casing is located proximate an uphole end of the lower casing, and wherein the lower casing is structured to be pressurized separately from the upper casing.

2. The downhole system of claim 1 , wherein the lower casing includes a second annular barrier, axially spaced from the first annular barrier, the second annular barrier having a second expandable metal sleeve expandable to be fastened to an inside surface of the borehole.

3. The downhole system of claim 2 , wherein the second annular barrier is connected to the outer surface of the lower casing.

4. The downhole system of claim 1 , wherein the upper casing has a diameter that is larger than a diameter of the lower casing.

5. The downhole system of claim 1 , further comprising a running tool detachably attached to an uphole end of the lower casing.

6. The downhole system of claim 5 , wherein the lower casing has an inside surface including a cavity and the running tool includes a dog that is retractably receivable in the cavity.

7. The downhole system of claim 5 , further comprising a disconnecting tool to detach the running tool from the lower casing.

8. The downhole system of claim 5 , further comprising a drill pipe attachable to the running tool.

9. The downhole system of claim 1 , wherein the lower casing has a diameter that is the same before and after the first expandable metal sleeve has been expanded.

10. A downhole system for deployment in a well bore, the downhole system comprising:

an upper casing having an inside surface; and

a lower casing having a first annular barrier including a first expandable metal sleeve, the first expandable sleeve being expandable upon application of pressurized fluid to engage the inside surface of the upper casing, to fasten the lower casing to the upper casing, the lower casing configured to allow fluid to flow directly through the lower casing and into the first annular barrier, the first annular barrier being positioned between the inside surface of the upper casing and the outer surface of the lower casing, such that the inside surface of the upper casing is radially spaced away from the outer surface of the lower casing after the first expandable metal sleeve has been expanded,

wherein:

the lower casing includes a second annular barrier, axially spaced downhole from the first annular barrier, the second annular barrier having a second expandable metal sleeve expandable upon application of the pressurized fluid to be fastened to an inside surface of the well bore,

the inner surface of the upper casing is located proximate a downhole end of the upper casing, and the first annular barrier of the lower casing is located proximate an uphole end of the lower casing,

the upper casing has a diameter that is larger than a diameter of the lower casing, and

the first and second annular barriers are connected to an outer surface of the lower casing.

11. The downhole system of claim 10 , further comprising a running tool detachably attached to the uphole end of the lower casing.

12. The downhole system of claim 11 , wherein the lower casing has an inside surface including a cavity and the running tool includes a dog that is retractably receivable in the cavity.

13. The downhole system of claim 11 , further comprising a disconnecting tool to detach the running tool from the lower casing.

14. The downhole system of claim 11 , further comprising a drill pipe attachable to the running tool.

15. A method for installing a downhole system in a borehole having an upper casing, the method comprising:

connecting a running tool to a lower casing having at least a first annular barrier with a first expandable metal sleeve,

connecting the running tool with a drill pipe,

lowering the drill pipe, running tool and the lower casing into the borehole, and

upon application of pressurized fluid, expanding the first expandable metal sleeve of the first annular barrier and connecting the lower casing with the upper casing via the first expandable metal sleeve, wherein the lower casing has an outer surface radially spaced away a distance from an inside surface of the upper casing after the first expandable sleeve has been expanded, the distance corresponding to a thickness of the first annular barrier after expansion, and wherein-the first sleeve is structured to be expanded via pressurized fluid introduced through the lower casing whilst the upper casing is isolated from the pressurized fluid applied to the lower casing and the first sleeve.

16. The method of claim 15 , wherein the method further comprises disconnecting the running tool from the lower casing using a disconnecting tool, and raising the running tool, the drill pipe and the disconnecting tool.

17. The method of claim 15 , wherein the lower casing has a second annular barrier with a second expandable metal sleeve adapted to fasten the lower casing to an inside surface of the borehole, and the first and second expandable metal sleeves are expanded with the pressurized fluid at substantially the same time.