Method and apparatus for wellbore fluid treatment
A method for fracturing a formation includes positioning a fluid treatment string in the formation. The fluid treatment string includes a port configured to pass fracturing fluid from within the string's inner bore to outside the string, and a sliding sleeve located inside string and configured to move by fluid pressure within the inner bore of the fluid treatment string between (i) a first position in which the sliding sleeve covers the port and (ii) a second position in which the sliding sleeve exposes the port to the inner bore. The method also includes applying a fluid pressure within the inner bore such that the sliding sleeve moves from the first position to the second position without the sliding sleeve engaging a sealing device, and pumping fracturing fluid through the inner bore and through the port to fracture a portion of the formation.
1. A method for fracturing a formation, the method comprising:
positioning a fluid treatment string in the formation, the fluid treatment string comprising:
a port configured to pass fracturing fluid from within an inner bore of the fluid treatment string to outside the fluid treatment string, and
a sliding sleeve located inside the fluid treatment string and configured to move by fluid pressure within the inner bore of the fluid treatment string between (i) a first position in which the sliding sleeve covers the port and (ii) a second position in which the sliding sleeve exposes the port to the inner bore of the fluid treatment string;
applying a fluid pressure within the inner bore of the fluid treatment string such that the sliding sleeve moves from the first position to the second position without the sliding sleeve engaging a sealing device; and
pumping fracturing fluid through the inner bore of the fluid treatment string and through the port to fracture a portion of the formation.
2. The method of claim 1 , wherein the formation comprises a hydrocarbon-containing formation.
3. The method of claim 1 , wherein the fracturing fluid comprises proppants.
4. The method of claim 3 , wherein the proppants comprise sand.
5. The method of claim 3 , wherein the proppants comprise bauxite.
6. The method of claim 3 , wherein the fluid treatment string comprises a casing string.
7. The method of claim 3 , wherein the fluid treatment string comprises a tubing string.
8. The method of claim 3 , wherein the port is the down-hole-most port of the tubing string through which fracturing fluid is pumped.
9. The method of claim 8 , wherein the port is adjacent a down hole end of the fluid treatment string.
10. The method of claim 3 , wherein the fluid treatment string further comprises a covering for the port.
11. The method of claim 3 , further comprising producing fluid from outside the fluid treatment string, through the port, and up hole through the inner bore of the fluid treatment string.
12. The method of claim 3 , wherein the sliding sleeve comprises a fluid actuated piston.
13. The method of claim 1 , wherein the fracturing fluid comprises a gel.
14. The method of claim 1 , wherein the fracturing fluid comprises an acid.
15. A fluid treatment string sub adapted to be connected to a tubing string for hydraulically fracturing a formation, the fluid treatment string sub comprising:
a port configured to pass fracturing fluid from an inner bore of the fluid treatment string sub to outside the fluid treatment string sub; and
a sliding sleeve located inside the fluid treatment string sub and configured to move by fluid pressure within the inner bore of the fluid treatment string, without requiring engagement with a sealing device, between
(i) a first position in which the sliding sleeve covers the port and
(ii) a second position in which the sliding sleeve exposes the port to the inner bore of the fluid treatment string sub,
wherein the fluid treatment string sub is adjacent a down hole end of the tubing string, and is the down-hole-most fluid treatment string sub of the tubing string that is configured to pass fracturing fluid, the fracturing fluid comprising proppants.
16. The fluid treatment string sub of claim 15 , wherein the formation comprises a hydrocarbon-containing formation.
17. The fluid treatment string sub of claim 15 , wherein the proppants comprise sand.
18. The fluid treatment string sub of claim 15 , wherein the proppants comprise bauxite.
19. The fluid treatment string sub of claim 15 , wherein the fluid treatment string sub is connected to a casing string.
20. The fluid treatment string sub of claim 15 , wherein the fluid treatment string sub further comprises a covering for the port.
21. The fluid treatment string sub of claim 15 , wherein the sliding sleeve comprises a fluid actuated piston.
22. The fluid treatment string sub of claim 15 , wherein the fracturing fluid comprises a gel.
23. The fluid treatment string sub of claim 15 , wherein the fracturing fluid comprises an acid.
24. A method for fracturing a formation, the method comprising:
positioning a fluid treatment string in the formation, the fluid treatment string comprising:
a port configured to pass fracturing fluid from within an inner bore of the fluid treatment string to outside the fluid treatment string, and a sliding sleeve located inside the fluid treatment string and configured to move by fluid pressure within the inner bore of the fluid treatment string between (i) a first position in which the sliding sleeve covers the port and (ii) a second position in which the sliding sleeve exposes the port to the inner bore of the fluid treatment string;
applying a fluid pressure within the inner bore of the fluid treatment string such that the sliding sleeve moves from the first position to the second position without the sliding sleeve engaging a sealing device;
and pumping a fracturing fluid comprising proppants through the inner bore of the fluid treatment string, through the port, and into the formation to fracture a portion of the formation.
25. The method of claim 24 , wherein the fluid treatment string comprises a tubing string.
26. The method of claim 24 , wherein the fluid treatment string comprises a casing string.