Realtime dogleg severity prediction

Patent metadata

Field	Value
Publication number	US-9043152-B2
Application number	US-201113204964-A
Country	US
Kind code	B2
Filing date	Aug 8, 2011
Priority date	Aug 8, 2011
Publication date	May 26, 2015
Grant date	May 26, 2015

Abstract

A method for estimating an inclination and azimuth at a bottom of a borehole includes forming a last survey point including a last inclination and a last azimuth; receiving at a computing device bending moment and at least one of a bending toolface measurement and a near bit inclination measurement from one or more sensors in the borehole; and forming the estimate by comparing possible dogleg severity (DLS) values with the bending moment value.

First claim

What is claimed is:

1. A computer-based method for estimating an inclination and azimuth at a bottom of a borehole, the borehole including a drill string with a bit at its end, the method comprising:
forming a last survey point including a last inclination and a last azimuth;
receiving at a computing device an actual bending moment value and a near bit inclination measurement from one or more sensors in the borehole; and
forming a plurality of sets of estimated inclination and azimuth values based on the last inclination and last azimuth;
forming an estimated bending moment value for each of the plurality of sets of estimated inclination and azimuth values;
comparing the actual bending moment value to the estimated bending moment value formed for each of the sets;
selecting an estimated bending moment value closest to the actual bending moment value;
selecting a set of estimated inclination and azimuth values corresponding to the selected estimated bending moment value as the estimated inclination and azimuth; and
changing a trajectory of the drill string based on the selected set;
wherein the plurality of sets of estimated inclination and azimuth values are limited to existing in a plane defined by the near bit inclination measurement.

2. The method of claim 1 , wherein the one or more sensors are included in a sensor sub located near the bottom of the borehole.

3. The method of claim 1 , further comprises:
determining a build rate based on the estimated inclination and azimuth.

4. The method of claim 1 , further comprises:
determining a turn rate based on the estimated inclination and azimuth.

5. The method of claim 1 , wherein the computing device is located at a surface location.

6. A computer program product for estimating an inclination and azimuth at a bottom of a borehole, the borehole including a drill string with a bit at its end, the computer program product including a non-transitory tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method comprising:
receiving a last survey point including a last inclination and a last azimuth;
receiving a bending moment value and a near bit inclination measurement from one or more sensors in the borehole; and
forming a plurality of sets of estimated inclination and azimuth values based on the last inclination and last azimuth;
forming an estimated bending moment for each of the sets of estimated inclination and azimuth values;
comparing the bending moment value to the estimated bending moment values formed for each of the sets;
selecting an estimated bending moment value closest to the bending movement value;
selecting a set of estimated inclination and azimuth corresponding to the selected estimated bending moment as the estimated inclination and azimuth; and
changing a trajectory of the drill string based on the selected set;
wherein the plurality of sets of estimated inclination and azimuth values are limited to existing in a plane defined by the near bit inclination measurement.

7. The computer program product of claim 6 , wherein the method further comprises:
determining a build rate based on the estimated inclination and azimuth.

8. The computer program product of claim 6 , wherein the method further comprises:
determining a turn rate based on the estimated inclination and azimuth.

Assignees

• Schuberth Frank
• Reckmann Hanno
• Macpherson John D
• Hood James Albert
• Baker Hughes Inc

Inventors

• Schuberth Frank
• Reckmann Hanno
• Macpherson John D
• Hood James Albert

Classifications

• E21B47/022 Primary

  of the borehole, e.g. using geomagnetism · CPC title

• E21B47/024

  of devices in the borehole (determining slope or direction of the borehole E21B47/022) · CPC title