Method for guiding a downhole tool assembly using an above-ground receiver system

• US 8,482,286 B2
• Filed: 05/27/2011
• Issued: 07/09/2013
• Est. Priority Date: 09/28/2007
• Status: Active Grant

• Current Assignee: Charles Machine Works Incorporated The
• Original Assignee: Charles Machine Works Incorporated The
• Inventors: Cole, Scott Bryan
• Primary Examiner(s): PATIDAR, JAY M
• Application Number:
  US13/117,264
• Publication Number:
  US 20110227575A1
• Time in Patent Office: 774 Days
• Field of Search: 324326-329, 175/45
• US Class Current: 324/326
• CPC Class Codes: E21B 47/0232 at least one of the energy sources or one of the detectors being located on or above the ground surface
• CPC Class Codes: G01R 33/02 Measuring direction or magnitude of magnetic fields or magnetic flux G01R33/20 takes precedence
• CPC Class Codes: G01V 3/15 specially adapted for use during transport, e.g. by a person, vehicle or boat
• CPC Class Codes: G01V 3/30 operating with electromagnetic waves

Abstract

A method for guiding a downhole tool assembly using a receiver system. The receiver system comprises two antenna assemblies disposed in a substantially horizontal plane. The antenna assemblies are set at a target point such that the two antenna assemblies each lie on a desired borepath. The two antenna assemblies simultaneously detect in three dimensions a magnetic field source transmitted from the downhole tool assembly to determine a position of the downhole tool assembly.

Claims

1. A method for guiding a downhole tool assembly, the method comprising:

setting a receiver assembly at a target point, the receiver assembly comprising two separate antenna assemblies disposed in a substantially horizontal plane, such that the two antenna assemblies each lie on a desired borepath;

moving the downhole tool assembly relative to the target point; and

simultaneously detecting in three dimensions at each of the two antenna assemblies a magnetic field transmitted from the downhole tool assembly to determine a position of the downhole tool assembly.

2. The method of claim 1 further comprising calculating the position of the downhole tool assembly in a vertical plane containing the desired borepath using the fields detected by the two antenna assemblies.

3. The method of claim 1 wherein the position of the downhole tool assembly comprises a depth of the downhole tool assembly and a horizontal distance to the downhole tool assembly.

4. The method of claim 1 further comprising the step of using the fields detected by the two antenna assemblies to calculate whether the downhole tool assembly is left or right of the desired borepath.

5. The method of claim 1 further comprising the steps of:

detecting a pitch of the downhole tool assembly; and

using the fields detected by the two antenna assemblies and the pitch of the downhole tool assembly to calculate a predicted depth of the downhole tool assembly when the downhole tool assembly is at the target point.

6. The method of claim 1 further comprising the step of using the fields detected by the two antenna assemblies to determine whether the downhole tool assembly is approaching or has passed the target point.

7. The method of claim 1 wherein the target point is a point a predetermined distance below the receiving assembly.

8. The method of claim 1 wherein the target point comprises a below-ground point, wherein setting the receiver assembly at the target point comprises positioning the receiver assembly on the ground above the target point.