Washpipeless frac pack system

• US 20060243440A1
• Filed: 04/29/2005
• Published: 11/02/2006
• Est. Priority Date: 04/29/2005
• Status: Active Grant

• Current Assignee: Baker Hughes Incorporated (Baker Hughes Company)
• Original Assignee: Baker Hughes Incorporated (Baker Hughes Company)
• Inventors: MacDonald, Kenneth, Corbett, Thomas G., Amaral, Anderson DeSilva, Triplett, William
• Granted Patent: US 7,290,610 B2
• Time in Patent Office: Days
• US Class Current: 166/278
• CPC Class Codes: E21B 34/06 in wells
• CPC Class Codes: E21B 43/04 Gravelling of wells
• CPC Class Codes: E21B 43/045 Crossover tools

Abstract

A frac pack system and method for operating a frac pack system wherein an isolation string assembly has a lower circulation valve with lateral flow ports that are operated to an open position without the use of shifters on a wash pipe. The isolation string assembly is incorporated into a frac pack assembly within a wellbore and includes an upper sleeve tool that provides selective production of fluids through the frac pack assembly. In addition, the isolation string includes a lower circulation valve having a sliding sleeve that is shiftable from an open position to a closed position upon receipt of a suitable pressure differential. This configuration is particularly valuable for permitting monitoring of pressure or other conditions in the annulus of the wellbore portion being packed during frac pack operations. Further, the lower circulation valve tool can be used to selectively allow fluid returns during the frac pack operation.

Claims

1. An isolation string for providing selective communication of fluid between an interior flowbore of the isolation string and a wellbore portion surrounding the isolation string, the isolation string being disposed radially within a screen in a frac pack system, defining an axial flowbore within and comprising:

a first valve for selective communication of fluid between the flowbore and the wellbore portion, the first valve being moveable between a closed-locked position, a closed-unlocked position, and an open-unlocked position; and

a second valve for selective communication of fluid between the flowbore and the wellbore portion, the second valve being moveable between an open and a closed position.

2. The isolation string of claim 1 wherein the second valve comprises a sliding sleeve valve having:

a valve body;

a flow area metering orifice disposed within the valve body for transmitting a predetermined rate of fluid between the flowbore and the wellbore portion; and

a sleeve member disposed radially within the valve body and axially moveable therewithin, the sleeve member being moveable between an open position, wherein fluid flow is permitted through the metering orifice, and a closed position, wherein fluid flow is blocked through the metering orifice.

3. The isolation string of claim 2 further comprising a device for locking the sleeve member in the closed position.

4. The isolation string of claim 2 further comprising a frangible shear member for releasably securing the sleeve member in the open position.

5. The isolation string of claim 1 wherein the second valve is disposed into the wellbore in the open position and remains in the open position during frac pack operations.

6. The isolation string of claim 5 wherein the second valve is moved to the closed position prior to commencement of production through the isolation string.

7. A frac pack system for placing solids in a wellbore and subsequently producing production fluid from the wellbore, the frac pack system comprising:

a service tool portion;

a solids placement portion having;

a screen;

an isolation string having an interior flowbore and providing selective communication of fluid between the interior flowbore and the wellbore surrounding the isolation string, the isolation string comprising;

a) a first valve for selective communication of fluid between the flowbore and the wellbore portion, the first valve being moveable between a closed-locked position, a closed-unlocked position, and an open-unlocked position; and

b) a second valve for selective communication of fluid between the flowbore and the wellbore portion, the second valve being moveable between an open and a closed position.

8. The frac pack system of claim 7 wherein the second valve of the isolation string is actuated between open and closed positions by varying fluid pressure within the flowbore of the isolation string.

9. The frac pack system of claim 7 wherein the first and second valves of the isolation string are actuated between positions by varying fluid pressure within the flowbore of the isolation string.

10. A method of conducting a frac pack operation within a wellbore, comprising the steps of:

disposing a service tool portion and solids placement portion within a wellbore, the solids placements portion having an isolation string with a flowbore defined therewithin;

flowing a frac pack solids-containing fluid into the wellbore; and

monitoring a wellbore condition during the step of flowing a solids-containing fluid into the wellbore.

11. The method of claim 10 further comprising the step of subsequently producing production fluid from the wellbore through the isolation string.

12. The method of claim 10 wherein the isolation string further comprises a plurality of valves and wherein at least one of said plurality of valves is in an open position during the step of flowing a frac pack solids-containing fluid into the wellbore so that monitoring of a wellbore condition may be conducted.

13. The method of claim 12 wherein the at least one valve is movable between an open position wherein fluid communication is provided between the wellbore and the flowbore and a closed position wherein there is no fluid communication between the wellbore and flowbore.

14. The method of claim 12 wherein the plurality of valves further comprises at least one valve that is moveable between a closed-locked position, a closed-unlocked position, and an open position.

15. The method of claim 13 wherein the at least one valve is actuated between its open and closed positions by varying fluid pressure within the flowbore of the isolation sleeve.

16. The method of claim 13 wherein the at least one valve is actuated between its open and closed positions by a pressure differential between the flowbore of the isolation sleeve and the wellbore.

17. The method of claim 10 further comprising the step of circulating fluid returns through the isolation string.

18. The method of claim 16 wherein the at least one valve comprises:

a valve body;

a flow area metering orifice disposed within the valve body for transmitting a predetermined rate of fluid between the flowbore and the wellbore portion; and

a sleeve member disposed radially within the valve body and axially moveable therewithin, the sleeve member being moveable between an open position, wherein fluid flow is permitted through the metering orifice, and a closed position, wherein fluid flow is blocked through the metering orifice.

19. The method of claim 18 further comprising locking the sleeve member in the closed position.

20. The method of claim 18 further comprising shearing a frangible shear member to release the sleeve member from the open position.