Methods and systems for picking up a drill bit

Patent metadata

Field	Value
Publication number	US-9683418-B2
Application number	US-201213649397-A
Country	US
Kind code	B2
Filing date	Oct 11, 2012
Priority date	Apr 12, 2010
Publication date	Jun 20, 2017
Grant date	Jun 20, 2017

Abstract

The present disclosure provides a method for picking up a drill bit off the bottom of an opening in a subsurface formation. The method includes setting a predetermined level of differential pressure across a mud motor at which pickup of the drill bit is to be initiated, and monitoring the differential pressure across the mud motor. The method also includes allowing differential pressure across the mud motor to decrease to the predetermined level, and when the predetermined level is reached, automatically picking up the drill bit.

First claim

The invention claimed is:

1. A method of picking up a drill bit off the bottom of an opening in a subsurface formation, comprising:
a) setting in a control system a predetermined level of differential pressure across a mud motor at which pickup of the drill bit is to be initiated by the control system;
b) monitoring the differential pressure across the mud motor using data from at least one sensor of the control system;
c) allowing differential pressure across the mud motor to decrease to the predetermined level;
d) when the predetermined level is reached, picking up the drill bit; and,
e) monitoring one or more forces during pickup, wherein a torque and drag model is applied by the control system to estimate at least one of the forces during pickup.

2. The method of claim 1 wherein the pickup is conducted after a maximum available depth for a length of drill pipe has been reached.

3. The method of claim 1 wherein the predetermined level is a user set point.

4. The method of claim 1 , further comprising triggering an alarm if the estimated force exceeds a user-defined amount.

5. The method of claim 1 , further comprising assessing an open hole friction factor during pickup of the drill bit.

6. The method of claim 1 , further comprising continuously assessing an open hole friction factor during at least a portion of a drilling operation.

7. The method of claim 6 , further comprising triggering an alarm if the open hole friction factor exceeds a predetermined amount.

8. The method of claim 1 , further comprising:
triggering at least one alarm condition based on a assessed value of at least one force or open hole friction factor, and
commencing a mitigation procedure based on the assessed value of the at least one force or open hole friction factor.

9. The method of claim 1 , further comprising continually assessing an open hole friction factor during at least a portion of a drilling operation to verify that acceptable well bore conditions exist as a permissive for completion of the at least one drilling operation.

Assignees

• Shell Oil Co

Inventors

• Edbury David Alston
• Guerrero Jose Victor
• Macdonald Duncan Charles
• Rogers James Bryon
• Sitton Donald Ray

Classifications

• E21B47/003

  Determining well or borehole volumes · CPC title

• E21B37/00

  Methods or apparatus for cleaning boreholes or wells (E21B21/00 takes precedence) · CPC title

• E21B44/02

  Automatic control of the tool feed ({E21B44/005,} E21B44/10 take precedence) · CPC title

• E21B44/00

  Automatic control systems specially adapted for drilling operations, i.e. self-operating systems which function to carry out or modify a drilling operation without intervention of a human operator, e.g. computer-controlled drilling systems; Systems specially adapted for monitoring a plurality of drilling variables or conditions · CPC title

• E21B49/005

  Testing the nature of borehole walls or the formation by using drilling mud or cutting data · CPC title