METHODS OF DETECTING, PREVENTING, AND REMEDIATING LOST CIRCULATION

• US 20090188718A1
• Filed: 01/30/2009
• Published: 07/30/2009
• Est. Priority Date: 01/30/2008
• Status: Active Grant

• Current Assignee: M-I LLC (Schlumberger NV)
• Original Assignee: M-I LLC (Schlumberger NV)
• Inventors: Sanders, Mark, Kaageson-Loe, Nils, Asko, Arne, Manescu, Gabe, Daatland, Trond, Randeberg, Oystein, Growcock, Frederick B.
• Granted Patent: US 8,401,795 B2
• Time in Patent Office: Days
• US Class Current: 175/40
• CPC Class Codes: E21B 21/003 Means for stopping loss of drilling fluid plastering the borehole wall E21B33/138

Abstract

A method for planning a wellbore, the method including defining drilling data for drilling a segment of a planned wellbore and identifying a risk zone in the segment. Additionally, the method including determining an expected fluid loss for the risk zone and selecting a solution to reduce fluid loss in the risk zone. Furthermore, a method for treating drilling fluid loss at a drilling location, the method including calculating a drilling fluid loss rate at the drilling location, classifying the drilling fluid loss based on the drilling fluid loss rate, and selecting a solution based at least in part on the classifying.

Claims

1. A method for planning a wellbore, the method comprising:

defining drilling data for drilling a segment of a planned wellbore;

identifying a risk zone in the segment;

determining an expected fluid loss for the risk zone; and

selecting a solution to reduce fluid loss in the risk zone;

2. The method of claim 1, further comprising:

adjusting a drilling plan to include the solution.

3. The method of claim 1, further comprising:

creating a drilling plan comprising the solution.

4. The method of claim 1, wherein the identifying comprises:

comparing drilling parameters for the planned wellbore to offset well data; and

determining, based on the comparing, the risk zone for the planned wellbore.

5. The method of claim 1, further comprising:

predicting a fracture width of the risk zone; and

determining an optimal drilling fluid parameter based on the predicted fracture width.

6. The method of claim 5, wherein the predicting comprises using drilling parameters and rock properties to predict the fracture width.

7. The method of claim 1, further comprising:

predicting an affect of the solution on a drilling tool assembly parameter.

8. The method of claim 1, wherein the drilling data comprises at least one of wellbore lithology, porosity, tectonic activity, fracture gradient, fluid type, fluid properties, hydraulic pressure, fluid composition, well path, rate of penetration, weight on bit, torque, drag, trip speed, bottom hole assembly design, bit type, drill pipe size, drill collar size, and casing location.

9. The method of claim 1, wherein the solution comprises:

providing a lost circulation treatment.

10. The method of claim 9, further comprising:

maintaining the lost circulation treatment.

11. A method for treating drilling fluid loss at a drilling location, the method comprising:

calculating a drilling fluid loss rate at the drilling location;

classifying the drilling fluid loss based on the drilling fluid loss rate; and

selecting a solution based at least in part on the classifying.

12. The method of claim 11, wherein the classifying consists of at least one of seepage, partial loss, total loss, severe complete loss, and underground blowout.

13. The method of claim 11, further comprising:

implementing the solution at the drilling location.

14. The method of claim 13, further comprising:

re-calculating the drilling fluid loss rate after implementing the solution; and

re-classifying the drilling fluid loss based on the recalculated rate of drilling fluid loss.

15. The method of claim 14, further comprising:

repeating the steps of re-calculating, reclassifying, and selecting until the drilling fluid loss reaches a target fluid loss.

16. The method of claim 14, further comprising:

selecting a second solution based at least in part on the re-classifying.

17. The method of claim 11, wherein the solution selected is based in part on at least one of a severity of the losses, a type of drilling fluid used, and a type of formation drilled, a fracture type, and a fracture gradient.

18. The method of claim 11, further comprising:

predicting a fracture width of the risk zone; and

determining an optimal drilling fluid parameter based on the predicted fracture width.

19. The method of claim 18, wherein the predicting comprises using drilling parameters and rock properties to predict the fracture width.

20. The method of claim 18, wherein the calculating comprises using a rate of fluid loss and a hydraulic pressure in the loss zone to calculate the fracture width.

21. The method of claim 15, further comprising:

determining whether the fluid loss is a surface fluid loss or a downhole fluid loss.