Method and apparatus to selectively reduce wellbore pressure during pumping operations

• US 20040231853A1
• Filed: 05/21/2003
• Published: 11/25/2004
• Est. Priority Date: 05/21/2003
• Status: Active Grant

• Current Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Original Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Inventors: Virally, Stephane J., Anyan, Steven L., Aardalsbakke, Olukemi Ibironke
• Granted Patent: US 7,128,160 B2
• Time in Patent Office: Days
• US Class Current: 166/373
• CPC Class Codes: E21B 34/10 operated by control fluid supplied from outside the borehole
• CPC Class Codes: E21B 43/045 Crossover tools

Abstract

The present invention provides for a tool having diverter valves to reduce the pressure in a wellbore caused by frictional resistance to fluid flow as the beta wave of a gravel pack operation makes its way up the wellbore.

Claims

1. A service tool for use in a well, comprising:

a tubular having a central passageway therethrough;

a crossover through which fluid flowing down the central passageway can exit the central passageway and enter a lower annulus below a packer and fluid flowing up the central passageway can exit the central passageway and enter an upper annulus above the packer;

a valve mounted to the tubular to allow or block fluid flow from the lower annulus into the central passageway through an opening in a wall of the tubular; and

in which

the valve is actuated by a pressure-responsive member.

2. The service tool of claim 1 in which the pressure-responsive member is a rupture disk.

3. The service tool of claim 1 in which the valve further comprises a housing and a piston sealingly and moveably mounted within the housing.

4. The service tool of claim 3 in which the housing further comprises an upper housing joined to a lower housing.

5. The service tool of claim 3 in which the piston and the housing form a chamber into which a piston head extends and divides the chamber into an upper chamber and a lower chamber.

6. The service tool of claim 5 in which the pressure-activated member is adjacent the upper chamber.

7. The service tool of claim 3 in which the piston has a lower end and an upper end, and in which the area of the lower end is greater than the area of the upper end.

8. The service tool of claim 3 in which the piston carries seals to control fluid flow.

9. The service tool of claim 1 in which the service tool is run through the packer and inside a screen.

10. The service tool of claim 1 in which a plurality of valves are spaced along the length of the service tool, and in which each valve is set to actuate independently from the other valves to an open state when the wellbore pressure reaches some predetermined threshold.

11. The service tool of claim 10 in which the wellbore pressure drops each time a valve is actuated to an open state.

12. The service tool of claim 10 in which the wellbore pressure never exceeds the fracture pressure of a wellbore formation.

13. A valve assembly for use in a well, comprising:

an upper housing having a port therethrough;

a lower housing joined to the upper housing, the lower housing having a pressure-responsive member therein;

a piston sealingly and moveably mounted within the upper and lower housings to form a chamber, the piston having a piston head extending into the chamber and sealingly dividing the chamber into an upper chamber and a lower chamber, the pressure-responsive member being adjacent to the upper chamber; and

in which

the piston allows or prevents fluid communication through the port.

14. The valve assembly of claim 13 in which the pressure-responsive member is a rupture disk.

15. The valve assembly of claim 13 in which actuation of the pressure-responsive member causes the piston to move, exposing the port.

16. The valve assembly of claim 13 in which the piston has a lower end and an upper end, and in which the area of the lower end is not equal to the area of the upper end.

17. The valve assembly of claim 13 in which the piston carries seals to control fluid flow paths.

18. A method to reduce wellbore pressure during pumping operations, comprising:

a) providing a service tool to which diverter valves can be mounted;

b) spacing the diverter valves along the service tool'"'"'s length;

c) setting each diverter valve to actuate independently from the other diverter valves to an open state when the wellbore pressure reaches some predetermined threshold;

d) placing the service tool in the wellbore; and

e) performing pumping operations.

19. The method of claim 18 in which placing the service tool in the wellbore further comprises running the service tool through a packer and inside a sand screen.

20. The method of claim 18 in which spacing the diverter valves further comprises computing the optimal locations for each diverter valve based on anticipated wellbore pressure and formation fracture pressure.