Remote hydraulic control of downhole tools

Patent metadata

Field	Value
Publication number	US-10443349-B2
Application number	US-201515555947-A
Country	US
Kind code	B2
Filing date	Apr 15, 2015
Priority date	Apr 15, 2015
Publication date	Oct 15, 2019
Grant date	Oct 15, 2019

Abstract

A well tool apparatus comprises a control arrangement configured to control response of the downhole tool by varying downhole drilling fluid conditions. The control arrangement includes a valve piston longitudinally slidable in a generally tubular controller housing that is in operation substantially co-axial with the wellbore, to open or close a valve port to a fluid flow connection between the drill strings interior and the tool. A latch mechanism is configured to latch the valve piston in an activated mode and/or a deactivated mode. Unlatching of the valve piston can be effected by displacement thereof in a particular axial direction to a mode change position. A stay member is automatically displaceable in the particular actual direction under hydraulic actuation responsive to above-threshold drilling fluid conditions, to obstruct movement of the valve piston under hydraulic actuation to the mode change position. The stay member can include a lock piston carrying a ball locking mechanism for obstructing axial movement of the valve piston.

First claim

What is claimed is:

1. An apparatus comprising:
a generally tubular housing configured for incorporation in a drill string which is to extend longitudinally along a borehole, the housing defining a longitudinally extending bore configured to convey drilling fluid through the housing;
a valve port configured for connection to a hydraulic tool activation mechanism of a tool incorporated in the drill string;
a valve piston that is longitudinally displaceable in the housing and that is configured to dispose the valve port from a closed condition to an open condition by longitudinal displacement of the valve piston in an opening direction, the valve port in the open condition permitting a fluid connection between the bore and the tool activation mechanism;
a latch mechanism configured for releasably latching the valve piston to the housing to restrain relative longitudinal movement of the valve piston, thereby to dispose the apparatus between operational modes comprising an activated mode in which the valve port is in the open condition upon application of drilling fluid pressures at or substantially above tool activation levels, and a deactivated mode in which the valve port is in the closed condition upon application of drilling fluid pressures at or substantially above tool activation levels, wherein the latch mechanism is configured to switch from one of the operational modes to the other in response to longitudinal movement of the valve piston to a mode change position;
a stay member that is automatically displaceable in the opening direction under hydraulic actuation in response to provision of drilling fluid pressures substantially above a trigger threshold level, to obstruct movement of the valve piston to the mode change position; and
wherein the stay member is configured to allow unobstructed movement of the valve piston to the mode change position in response to provision of drilling fluid pressures at levels below the trigger threshold level for at least a trigger threshold interval.

2. The apparatus of claim 1 , wherein the stay member is configured for preventing, in response to provision of drilling fluid pressures substantially above the trigger threshold level, both:
mode change from the activated mode to the deactivated mode, by obstructing movement of the valve piston in the opening direction before the valve piston reaches an unlatching position; and
mode change from the deactivated mode to the activated mode, by obstructing movement of the valve piston in the opening direction before the valve piston reaches a latching position.

3. The apparatus of claim 2 , wherein the latch mechanism is configured to latch the mechanism in the activated mode by preventing return of the valve piston for movement thereof in a closing direction into a longitudinal position in which the valve port is in the closed condition, the closing direction being opposite to the opening direction.

4. The apparatus of claim 2 , wherein the valve piston and the lock piston overlap axially in at least an overlap portion, the lock piston carrying an obstruction element that is located in the overlap portion and is configured to be movable by longitudinal movement of the lock piston between a clearing position in which relative longitudinal movement of the valve piston sufficient for movement to the mode change position is allowed, and an obstructing position in which the obstruction element is configured to obstruct movement of the valve piston to the mode change position.

5. The apparatus of claim 4 , wherein the lock piston is configured: to move the obstruction element from the clearing position to the obstructing position by hydraulically actuated longitudinal movement of the lock piston in the opening direction in response to provision of drilling fluid pressures substantially above the trigger threshold level; and wherein the lock piston is configured to move the obstruction element, when the obstruction element is in the obstructing position, from the obstructing position to the clearing position by longitudinal movement of the lock piston in a closing direction opposite to the opening direction, in response to cessation of drilling fluid pressures substantially above the trigger threshold level.

6. The apparatus of claim 4 , wherein the lock piston is configured to keep the obstruction element in the clearing position in response to provision of drilling fluid pressures below the trigger threshold level.

7. The apparatus of claim 4 , wherein the obstruction element is anchored to the lock piston for longitudinal movement therewith, and is radially displaceable relative to the valve piston in response to longitudinal movement between the obstructing position and the clearing position.

8. The apparatus of claim 7 , wherein the obstruction element is held captive against radial escape from the valve piston by a radially outer periphery of the valve piston in the overlap portion and a radially inner periphery of a chamber wall incorporated in the housing and defining at least part of a locking chamber in which the obstruction element is located.

9. The apparatus of claim 8 , wherein the chamber wall of the locking chamber is configured to define a release portion and a constricted portion, an inner diameter of the chamber wall being smaller in the constricted portion than in the release portion, the obstruction element being switchable from the clearing position to the obstructing position by longitudinal movement thereof from the release portion to the constricted portion caused by movement of the lock piston in the opening direction.

10. The apparatus of claim 4 , wherein the obstruction element is a roller configured for rolling along a radially outer periphery of the valve piston in the overlap portion.

11. The apparatus of claim 4 , wherein the obstruction element is a ball.

12. The apparatus of claim 4 , wherein the valve piston and the lock piston comprise substantially tubular parts mounted co-axially within the housing in end-to-end arrangement, the valve piston and lock piston having respective end portions that are telescopically received one within the other in the overlap portion, the obstruction element being located in a generally annular volume between a radially outer periphery of the valve piston and the housing.

13. The apparatus of claim 4 , wherein the valve piston carries one or more interference formations in the overlap portion, each interference formation comprising a radial protrusion on a radially outer surface of the valve piston, the radial protrusion being configured for obstructive engagement with the obstruction element when it is located in the constricted portion of the locking chamber.

14. The apparatus of claim 13 , wherein each interference formation comprises an inclined contact surface configured for wedging engagement with the obstruction element in the obstructing position.

15. The apparatus of claim 13 , wherein the one or more interference formations comprises a pair of axially spaced interference formations, one of the pair of interference formations being configured for obstructive engagement with the obstruction element to prevent movement of the valve piston, when latched, into the unlatching position, and the other one of the pair of interference formations being configured for obstructive engagement with the obstruction element to prevent movement of the valve piston, when unlatched, into the latching position.

16. The apparatus of claim 1 , herein the downhole tool comprises a reamer assembly, the reamer assembly comprising:
a tubular reamer body longitudinally aligned wi

Assignees

• Halliburton Energy Services Inc

Inventors

• Evans Benjamin
• Roche Olivier Christophe
• Lassoie Jean-Pierre

Classifications

• E21B23/006 Primary

  "J-slot" systems, i.e. lug and slot indexing mechanisms · CPC title

• E21B34/08 Primary

  responsive to flow or pressure of the fluid obtained (E21B34/10 takes precedence) · CPC title

• E21B34/16

  Control means therefor being outside the borehole {(control systems for submerged well heads E21B33/0355)} · CPC title

• E21B10/32

  with expansible cutting tools · CPC title

• E21B34/102 Primary

  with means for locking the closing element in open or closed position (E21B34/105 and E21B34/108 take precedence) · CPC title