Advanced drill string communication system, components and methods

Patent metadata

Field	Value
Publication number	US-9274243-B2
Application number	US-201313733097-A
Country	US
Kind code	B2
Filing date	Jan 2, 2013
Priority date	Jan 5, 2012
Publication date	Mar 1, 2016
Grant date	Mar 1, 2016

Abstract

A drill string communication system is described. An uphole transceiver can couple a signal onto the drill string at a power that is always greater that a selectable power for a downhole signal. Communication from a drill rig to an inground tool can be re-initiated using a maximum uphole transmit power of an uphole transceiver. A procedure can establish a new set of transmission parameters for a drill string signal to establish communication between the drill rig and the inground tool. The system can include a walkover locator that receives an active/inactive status-controlled electromagnetic locating signal. Responsive to a locating signal degradation, a reconfiguration command can modify the locating signal. The uphole transceiver and a downhole transceiver can automatically modify at least one parameter of a downhole signal. An uphole receiver can apply a compensation response to a transferred signal to compensate for a drill string channel transfer function.

First claim

What is claimed is:

1. A system for performing an inground operation at least which utilizes a drill string extending from a drill rig to an inground tool as an electrical conductor to provide communication therebetween, said system comprising:
a downhole transceiver located downhole proximate to the inground tool which is configured (i) to receive at least one sensor signal relating to an operational parameter of the inground tool, (ii) to generate a downhole signal that is transmitted to the drill rig on the drill string and which downhole signal is modulated based on the sensor signal, and (iii) to emanate an electromagnetic locating signal for above ground detection which locating signal is unmodulated at least by said sensor signal and selectively transmitted simultaneously with said downhole signal;
an uphole transceiver located at the drill rig including an uphole receiver that is configured to receive the downhole signal from the drill string and to recover the sensor signal such that information relating to the operational parameter is available at the drill rig; and
a walkover locator for receiving the electromagnetic locating signal to serve as at least one of a homing beacon and a tracking signal such that a detection range of the locating signal for a given transmission power without modulation is greater than the detection range of a modulated locating signal modulated by said sensor signal at the same, given transmission power.

2. The system of claim 1 wherein the downhole transceiver is configured to transmit the electromagnetic location signal at least approximately as a pure tone and the walkover locator includes a narrow band filter that is centered on a carrier frequency of the electromagnetic locating signal to detect at least approximately no more than the pure tone.

3. The system of claim 1 wherein the walkover locator is configured for telemetry communication with the uphole transceiver at the drill rig at least for correlation of sensor related data transferred to the uphole transceiver on the drill string from the inground tool with walkover locator generated data transferred by an electromagnetic telemetry signal to the uphole transceiver.

4. A system for performing an inground operation at least which utilizes a drill string extending from a drill rig to an inground tool as an electrical conductor to provide communication therebetween, said system comprising:
an uphole transceiver located at the drill rig including an uphole transmitter that is configured at least to transmit an uphole signal on the drill string to the inground tool;
a downhole transceiver located downhole proximate to the inground tool which is configured to receive the uphole signal from the drill string and to selectively emanate an electromagnetic locating signal for above ground detection;
a walkover locator for receiving the electromagnetic locating signal and for automatically detecting an active/inactive status of the walkover locator and, responsive to detecting a change in the active/inactive status, said walkover locator is configured to transmit a status indication to the drill rig that is indicative of a new active/inactive status; and
said uphole transceiver and said downhole transceiver are further configured to cooperate at least to turn off the electromagnetic locating signal responsive to the inactive state.

5. The system of claim 4 wherein the walkover locator is configured to actively use the electromagnetic locating signal during an active state of the walkover locator and to shut down components and/or processes of the walkover locator that are involved in detection and processing of the electromagnetic locating signal during an inactive state of the walkover locator.

6. The system of claim 4 wherein the walkover locator includes at least one accelerometer that produces an accelerometer output responsive to movement of the walkover locator and the walkover locator is configured to detect the inactive state based on said accelerometer output.

7. The system of claim 4 wherein the walkover locator includes a sensor that detects proximity of the locator to a surface of the ground and the walkover locator is configured to indicate the inactive state responsive to the locator being positioned on the surface of the ground.

8. A communication system forming part of a system for performing an inground operation at least which utilizes a drill string extending from a drill rig to an inground tool and a walkover detector to serve as at least one of a homing beacon and a tracking device, said communication system comprising:
an uphole transceiver located at the drill rig;
a downhole transceiver located downhole proximate to the inground tool;
a telemetry transceiver forming part of the walkover locator;
a first bidirectional communication link between the uphole transceiver and the downhole transceiver which uses the drill string as an electrical conductor to provide communication therebetween;
a second bidirectional communication link between the uphole transceiver and the telemetry transceiver of the walkover locator which employs wireless electromagnetic communication therebetween; and
at least a unidirectional communication link from the downhole transceiver of the inground tool to the walkover locator such that (i) a first communication mode is provided from the downhole transceiver to the uphole transceiver at the drill rig via the drill string using the first bidirectional communication link, (ii) a second communication mode is provided from the downhole transceiver to the uphole transceiver via the unidirectional communication link, the telemetry transceiver at the walkover locator and the second bidirectional communication link, and (iii) a controller for managing communication between the downhole transceiver and the uphole transceiver based at least in part on system status.

9. The system of claim 8 wherein said controller includes a communication manager at least for managing communication from the downhole transceiver at the inground tool to the uphole transceiver at the drill rig by automatically selecting between the first communication mode and the second communication mode for any given transmission from the inground tool to the drill rig based at least in part on a current operational status of the first and second bidirectional communication links and the unidirectional communication link.

10. The system of claim 9 wherein the controller is configured to select the first communication mode as a default mode.

Assignees

• Merlin Technology Inc

Inventors

• Chau Albert W
• Lam Loc Viet

Classifications

• E21B47/125

  using earth as an electrical conductor (by electromagnetic energy E21B47/13) · CPC title

• G01V3/30 Primary

  operating with electromagnetic waves · CPC title

• E21B7/046 Primary

  horizontal drilling (drilling with mechanical conveying means E21B7/003) · CPC title

• E21B7/30

  without earth removal · CPC title

• E21B47/091

  Fixed Constructions · mapped topic