Drill bit design selection and use

Patent metadata

Field	Value
Publication number	US-11704453-B2
Application number	US-201916433937-A
Country	US
Kind code	B2
Filing date	Jun 6, 2019
Priority date	Jun 6, 2019
Publication date	Jul 18, 2023
Grant date	Jul 18, 2023

Abstract

Systems and methods are disclosed for selecting a drill bit design that reduces or eliminates bit induced stick-slip. In some embodiments, each of a set of test drill bits is correlated with stick-slip events, wherein each of the test drill bits has a different design pattern comprising a combination of structural attributes. The design pattern stick-slip correlation includes, for each of the test drill bits, detecting variations in motion of the test drill bit during drilling operation. Stick-slip for each of the test drill bits is detected based on the detected variations in motion of the test drill bits during operation. The correlation further includes in response to detecting stick-slip, recording a stick-slip event in association with the corresponding test drill bit. The method further includes determining a performance efficiency value for each of the plurality of test drill bits and correlating the determined performance efficiency values with the stick-slip events to determine a threshold performance efficiency value. A design pattern for a drill bit is selecting or determined based, at least in part, on the threshold performance efficiency value.

First claim

What is claimed is:

1. A method comprising:
correlating each of a plurality of test drill bits with stick-slip events, each of the plurality of test drill bits having a different design pattern comprising a combination of structural attributes, wherein said correlating comprises, for each of the plurality of test drill bits,
detecting variations in motion of the test drill bit during drilling operation;
detecting stick-slip based on the detected variations in motion of the test drill bit; and
in response to detecting stick-slip, recording a stick-slip event in association with the test drill bit;

determining a drilling efficiency value for each of the plurality of test drill bits;
correlating the determined drilling efficiency values with the stick-slip events to determine a threshold performance efficiency value, wherein the threshold performance efficiency value is a value above or below which bit induced stick-slip does not occur; and
selecting and constructing a drill bit having a design pattern based, at least in part, on the threshold performance efficiency value.

2. The method of claim 1 , wherein each of the test drill bits includes a motion sensor comprising components for detecting rotational speed and acceleration, said detecting variations in motion of the test drill bit comprising detecting rotational speed and acceleration of the test drill bit.

3. The method of claim 2 , wherein said detecting the stick-slip comprises detecting a reduction in drill bit rotational speed to at or about zero.

4. The method of claim 2 , further comprising:
classifying a detected stick-slip as a bit induced stick-slip based, at least in part, on rotational speed and acceleration of the test drill bit and
wherein said recording the stick-slip event comprises recording the stick-slip event as a bit induced stick-slip event.

5. The method of claim 4 , wherein said classifying a detected stick-slip comprises classifying a detected stick-slip as a bit induced stick-slip based on a relatively high axial vibration during a slip phase and a coupling of axial vibration and torsional vibration.

6. The method of claim 2 , further comprising:
classifying a detected stick-slip as being a drill string induced stick-slip based, at least in part, on rotational speed and acceleration of the test drill bit; and
wherein said recording the stick-slip event comprises recording the stick-slip event as excluded from bit induced stick-slip events.

7. The method of claim 6 , wherein said classifying a detected stick-slip comprises classifying a detected stick-slip as being a drill string induced stick-slip based on a relatively low axial vibration during a slip phase and absence of coupling of axial vibration and torsional vibration.

8. The method of claim 1 , wherein said correlating the determined drilling efficiency values with the stick-slip events comprises:
determining, among the plurality of test drill bits having a recorded bit induced stick-slip event, a test drill bit having a highest drilling efficiency value; and
determining the threshold performance efficiency value to be higher than the highest drilling efficiency value.

9. The method of claim 1 , further comprising:
determining variations in the drilling efficiency value corresponding to variations in one or more of the structural attributes within the design patterns;
assigning a weighting to one or more of the structural attributes within the design patterns based on the determined variations;
wherein said selecting and constructing a drill bit comprises selecting or determining a design pattern based, at least in part, on the threshold performance efficiency value and the assigned weighting of the one or more structural attributes.

10. The method of claim 1 , wherein determining the drilling efficiency value for each of the plurality of test drill bits comprises determining an average drilling efficiency value for each of the plurality of test drill bits using a bit rock model.

11. The method of claim 1 , wherein the drilling efficiency value is a reactive torque value, and wherein determining a reactive torque value for each of the plurality of test drill bits comprises determining an average reactive torque value for each of the plurality of test drill bits.

12. The method of claim 1 , wherein the drilling efficiency value is a slop of reactive torque versus depth of cut per revolution, and wherein determining a slop value for each of the plurality of test drill bits comprises determining an average slop value for each of the plurality of test drill bits.

13. The method of claim 1 , wherein said determining a drilling efficiency value comprises:
for each of the plurality of test drill bits,
determining a weight-on-bit (WOB) during said operation;
measuring a rotation speed (RPM) during said operation;
determining a torque-on-bit (TOB) during said operation; and
determining a drill bit specific energy (E s ) based, at least in part, on the WOB, RPM, TOB, and a borehole cross-section area (A).

14. The method of claim 13 , wherein said determining E s comprises, for each of the test drill bits, determining a rate-of-penetration (ROP) during said operation and computing E s in accordance with the relation:

E
s

=

WOB
A

+

120
⁢

⁢

π
⁡

(
RPM
)

⁢

(
TOB
)

A
⁡

(
ROP
)

.

15. The method of claim 14 , wherein said determining a drilling efficiency value comprises:
determining compressive rock strength, σ rock , of formation material proximate to the operation of one or more of the plurality of test drill bits; and
determining a drilling efficiency (DE) in accordance with the relation

DE
=

σ
rock

E
s

.

16. A system comprising:
a processor;
a non-transitory computer-readable medium having instructions stored thereon that are executable by the processor to cause a drill bit design apparatus to,
correlate each of a plurality of test drill bits with stick-slip events, each of the plurality of test drill bits having a different design pattern comprising a different combination of structural attributes, wherein said

Assignees

• Halliburton Energy Services Inc

Inventors

• Chen Shilin

Classifications

• G06F30/17 Primary

  Mechanical parametric or variational design · CPC title

• E21B10/00

  Drill bits (specially adapted for deflecting the direction of boring {E21B7/064}; with means for collecting substances E21B27/00) · CPC title

• E21B10/54 Primary

  the bit being of the rotary drag type, e.g. fork-type bits · CPC title

• E21B47/007

  Measuring stresses in a pipe string or casing (for locating blocked portions of pipes E21B47/09) · CPC title

• E21B2200/20

  Computer models or simulations, e.g. for reservoirs under production, drill bits · CPC title