Method and apparatus for sealing an undesirable formation zone in the wall of a wellbore

Patent metadata

Field	Value
Publication number	US-10030467-B2
Application number	US-201514663812-A
Country	US
Kind code	B2
Filing date	Mar 20, 2015
Priority date	Mar 20, 2014
Publication date	Jul 24, 2018
Grant date	Jul 24, 2018

Abstract

An apparatus for sealing a section of a wall of a wellbore adjoining a target zone containing undesirable fluids for preventing penetration of the undesirable fluids into the wellbore is described. The apparatus includes an inflatable balloon deployable in the wellbore, a coiled tubing for deploying the inflatable balloon into the wellbore and an inflating assembly tool for inflating the balloon to form a seal over the adjacent target zone of the well bore wall.

First claim

What is claimed is:

1. An apparatus for sealing a section of a wall of a wellbore adjoining a target zone containing undesirable fluids for preventing penetration of the undesirable fluids into the wellbore, the apparatus comprising:
an inflatable balloon deployable in the wellbore, the balloon comprising a central section, and upper and lower sections located, respectively, on opposite ends of the central section, each section configured to inflate in response to receiving formation plugging fluid, wherein the central section comprises a plurality of weakened areas configured to rupture during inflation to discharge the formation plugging fluid;
a coiled tubing for deploying the inflatable balloon into the wellbore; and
an inflating assembly tool for inflating the balloon to form a seal over the adjacent target zone of the well bore wall.

2. An apparatus for sealing a section of a wall of a wellbore adjoining a target zone containing undesirable fluids for preventing penetration of the undesirable fluids into the wellbore, the apparatus comprising:
an inflatable balloon deployable in the wellbore, the balloon comprising a central section, and upper and lower sections located, respectively, on opposite ends of the central section;
a coiled tubing for deploying the inflatable balloon into the wellbore; and
an inflating assembly tool for inflating the balloon to form a seal over the adjacent target zone of the well bore wall, wherein the assembly tool comprises an inflating container filled with a formation plugging fluid and having at least three pressure-operated inflating valves for passing pressurized plugging fluid into the respective sections of the balloon.

3. An apparatus according to claim 2 , wherein the central section of the balloon has a plurality of weakened areas configured to rupture during inflation to discharge plugging fluid.

4. An apparatus according to claim 2 , wherein the downhole end of the coiled tubing is secured in fluid communication to a timed circulation valve, the timed circulation valve being programmed to be open for a predetermined time to circulate wellbore fluid into the coiled tubing while the balloon is lowered to a predetermined target zone, the timed circulation valve being set to close at a predetermined time required for pumping a fluid reactant via the coiled tubing from the surface to the circulation valve depth.

5. An apparatus according to claim 4 , wherein an outlet of the circulation valve is in fluid communication with a chemical container containing a chemical reactant that produces an exothermic reaction upon addition of the fluid reactant, the chemical container in fluid communication with the timed circulation valve via a pressure-operated inlet valve programmed to open at a predetermined pressure to allow the fluid reactant to enter the chemical container, whereby a controlled explosive reaction occurs, the chemical container having a pressure-operated exit valve set to open under the pressure generated by the chemical reaction to admit reaction products into the inflating container, the inflating valves opening at a predetermined pressure in the inflating container to admit formation plugging fluid to inflate the sections of the balloon.

6. An apparatus according to claim 2 , in which the inflating valves for the upper and lower sections are configured to provide a greater flow rate of the plugging fluid into the upper and lower balloon sections than the flow rate of plugging fluid into the central section, whereby the upper and lower sections are inflated more rapidly than the central section to provide fluid-tight seals against the wall of the well bore at opposite ends of the central section.

7. An apparatus according to claim 2 , wherein upper and lower inflatable packers are secured and positioned above and below the inflatable balloon in axial alignment with the coiled tubing.

8. An apparatus according to claim 7 , wherein each of the inflatable packers includes an electric pump in fluid communication with fluid in the wellbore.

9. An apparatus according to claim 7 , wherein the inflatable assembly tool comprises an inflating container filled with a formation plugging fluid and at least one pressure-operated inflating valve for passing pressurized plugging fluid into the inflatable balloon.

10. An apparatus according to claim 9 , wherein the balloon has a plurality of weakened areas configured to rupture during inflation to discharge plugging fluid.

11. An apparatus according to claim 9 , which includes a timed circulation valve positioned below the upper inflatable packer in fluid communication with the coiled tubing, the timed circulation valve being programmed to be open for a predetermined time to circulate wellbore fluid into the coiled tubing while the balloon is lowered to a predetermined target zone, the timed circulation valve being set to close at a predetermined time required for pumping a fluid reactant via the coiled tubing from the surface to the circulation valve depth.

12. An apparatus according to claim 11 , wherein an outlet of the circulation valve is in fluid communication with a chemical container containing a chemical reactant that produces an exothermic reaction upon addition of the fluid reactant, the chemical container in fluid communication with the timed circulation valve via a pressure-operated inlet valve programmed to open at a predetermined pressure to allow the fluid reactant to enter the chemical container, whereby a controlled explosive reaction occurs, the chemical container having a pressure-operated exit valve set to open under the pressure generated by the chemical reaction to admit reaction products into the inflating container, the inflating valve opening at a predetermine pressure in the inflating container to admit formation plugging fluid to inflate the balloon.

13. A method of sealing a section of a wall of a well bore adjoining a target zone containing undesirable fluids for preventing penetration of the undesirable fluids into the well bore, the method comprising the steps of:
deploying an inflatable balloon in the wellbore using a coiled tubing;
initiating an exothermic reaction to form reaction products;
flowing the reaction products into the balloon;
inflating, by the reaction products, the balloon to expand against and form a seal with the wall of the target zone; and
contacting the reaction products with the interior of the inflated balloon to melt and separate the portion of the balloon in contact with the wall of the wellbore.

14. A method according to claim 13 , wherein the inflatable balloon is deployed with a timed circulation valve which is programmed to keep the timed circulation valve open for a predetermined time necessary to circulate wellbore out of the well bore while the balloon is lowered to the predetermined target zone, introducing a fluid reactant into the coiled tubing and pumping said fluid reactant until it reaches the timed circulation valve, closing the timed circulation valve at the end of a predetermined time period required to pump the fluid reactant to the depth of the timed circulation valve, increasing pressure of the fluid reactant in the coiled tubing to a level sufficient to open a pressure-operated inlet valve that is located downstream of the timed circulation valve.

15. A method according to claim 14 , comprising the steps of providing a chemical container containing a chemical reactant that produces an exothermic chemical reaction upon addition of a fluid reactant, introducing the fluid reactant into the chemical container to produce an exothermic controlled explosive reaction, and

Assignees

• Saudi Arabian Oil Co

Inventors

• Al-Gouhi Waleed Abdullah

Classifications

• E21B33/12 Primary

  Packers; Plugs (used for cementing E21B33/134, E21B33/16) · CPC title

• E21B33/1272 Primary

  inflated by down-hole pumping means operated by a pipe string · CPC title

• E21B33/127

  with inflatable sleeve (E21B33/122, E21B33/124 take precedence) · CPC title

• E21B34/10

  operated by control fluid supplied from outside the borehole · CPC title

• E21B33/138

  Plastering the borehole wall; Injecting into the formation · CPC title