Advanced inground operations, system and associated apparatus
First Claim
1. A method for use in conjunction with a horizontal directional drilling system that includes a drill string that extends from a drill rig to an inground tool such that extension and retraction of the drill string generally produces corresponding movements of the inground tool during an inground operation, said drill string defining a through passage for carrying a pressurized flow of drilling mud from the drill rig to the inground tool for emission from the inground tool, said method comprising:
- during the inground operation, monitoring an annular mud pressure in the ground surrounding the inground tool;
detecting a decrease in the annular mud pressure;
continuing to monitor the annular mud pressure subsequent to detecting said decrease for a recovery in the annular mud pressure such that a negative going pulse is defined in the annular mud pressure; and
initiating a response as being indicative of a potential cross-bore.
1 Assignment
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Accused Products
Abstract
Systems, apparatus and methods are described for purposes of initiating a response to detection of an adverse operational condition involving a system including a drill rig and an inground tool. The response can be based on an uphole sensed parameter in combination with a downhole sensed parameter. The adverse operational condition can involve cross-bore detection, frac-out detection, excessive downhole pressure, a plugged jet indication and drill string key-holing detection. A communication system includes an inground communication link that allows bidirectional communication between a walkover detector and the drill rig via the inground tool. Monitoring of inground tool depth and/or lateral movement can be performed using techniques that approach integrated values. Bit force based auto-carving is described in the context of an automated procedure.
42 Citations
16 Claims
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1. A method for use in conjunction with a horizontal directional drilling system that includes a drill string that extends from a drill rig to an inground tool such that extension and retraction of the drill string generally produces corresponding movements of the inground tool during an inground operation, said drill string defining a through passage for carrying a pressurized flow of drilling mud from the drill rig to the inground tool for emission from the inground tool, said method comprising:
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during the inground operation, monitoring an annular mud pressure in the ground surrounding the inground tool; detecting a decrease in the annular mud pressure; continuing to monitor the annular mud pressure subsequent to detecting said decrease for a recovery in the annular mud pressure such that a negative going pulse is defined in the annular mud pressure; and initiating a response as being indicative of a potential cross-bore. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
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14. A method for use in conjunction with a horizontal directional drilling system that includes a drill string that extends from a drill rig to an inground tool such that extension and retraction of the drill string generally produces corresponding movements of the inground tool during an inground operation, said drill string defining a through passage for carrying a pressurized flow of drilling mud from the drill rig to the inground tool for emission from the inground tool, said method comprising:
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during the inground operation, monitoring an annular mud pressure in the ground surrounding the inground tool; detecting a decrease in the annular mud pressure; initiating a response based at least in part on detecting said change as being indicative of one of a potential cross-bore and a potential frac-out; measuring a rate of change of the decrease in the annular mud pressure; and distinguishing between the potential cross-bore and the potential frac-out based on the rate of change for use in initiating said response. - View Dependent Claims (15)
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16. An apparatus for use in conjunction with a horizontal directional drilling system that includes a drill string that extends from a drill rig to an inground tool such that extension and retraction of the drill string generally produces corresponding movements of the boring tool through the ground during an inground operation, said drill string defining a through passage for carrying a pressurized flow of drilling mud from the drill rig to the inground tool for emission from the inground tool, said apparatus comprising:
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a sensor for sensing an annular mud pressure in the ground surrounding the inground tool during the inground operation to produce a sensor output; and a processor receiving the sensor output and configured for monitoring the annular mud pressure based on the sensor output and for continuing to monitor the annular mud pressure subsequent to detecting said decrease for a recovery in the annular mud pressure such that a negative going pulse is defined in the annular mud pressure and issuing a warning responsive to identification of the negative going pulse.
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Specification