Hydraulic control of borehole tool deployment

Patent metadata

Field	Value
Publication number	US-2016251920-A1
Application number	US-201314387276-A
Country	US
Kind code	A1
Filing date	Oct 31, 2013
Priority date	Oct 31, 2013
Publication date	Sep 1, 2016
Grant date	—

Abstract

A control mechanism for a drill string tool is configured to activate the drill string tool by hydraulically actuated movement of the switching element to an activated position, with drilling mud serving as actuating medium. Movement of the switching element to the activated position is automatically regulated, so that tool activation is conditional upon application of above-threshold downhole drilling fluid conditions for at least a predetermined switching duration. A switch regulator that regulates movement of the switching element to the activated position can be configured to regulate a rate of movement of the switching element such that a substantially constant switching duration is maintained regardless of fluctuations in the magnitude of an actuating pressure differential during above-threshold downhole drilling fluid conditions.

First claim

What is claimed is:

1 . A well tool comprising:
a housing configured for incorporation in a drill string to convey drilling fluid along an internal bore defined by the housing; a valve body within the housing, the valve body defining a valve port in fluid communication with the internal bore and with an activation volume configured for cooperation with a hydraulic deployment mechanism of a drill string tool; a valve closing element configured for switching between an open condition in which the internal bore is in fluid communication with the activation volume, via the valve port, and a closed condition in which the closing element substantially prevents fluid flow through the valve port; a switch ram coupled to the valve closing element and configured for hydraulically driven movement in an activation direction in response to predefined above-threshold downhole drilling fluid conditions, to switch the valve closing element from the open condition to the closed condition; and a switch regulator coupled to the switch ram and configured to regulate switching of the valve closing element from the closed condition to the open condition by providing regulated hydraulic resistance to movement by the switch ram in the activation direction.

2 . The well tool of claim 1 , wherein the switch regulator comprises a switch timing mechanism configured to regulate a switching duration for hydraulically actuated movement of the valve closing element from the closed condition to the open condition in response to continuous exposure to above-threshold drilling fluid conditions, so that the switching duration is substantially independent of variations in the above-threshold drilling fluid conditions between respective instances of tool deployment.

3 . The well tool of claim 1 , wherein the switch regulator includes a hydraulic constriction through which a hydraulic medium is flowable in response to movement of the switch ram in the activation direction, the switch mechanism being configured such that a speed of movement by the switch ram in the activation direction is limited by a rate of flow of the hydraulic medium through the hydraulic constriction.

4 . The well tool of claim 3 , wherein the switch regulator further comprises a flow regulator mounted in the hydraulic constriction and configured to regulate flow of the hydraulic medium through the hydraulic constriction.

5 . The well tool of claim 4 , wherein the flow regulator comprises a flow rate control device configured to restrict a rate of flow of the hydraulic medium through the hydraulic constriction to a predetermined flow rate limit which is substantially consistent and is independent of fluctuations in a pressure differential across the hydraulic constriction during above-threshold drilling fluid conditions.

6 . The well tool of claim 3 , wherein the switch regulator comprises:
a regulator volume filled with the hydraulic medium and configured to be automatically pressurized in response to movement of the switch ram in the activation direction; and an evacuation passage providing a fluid flow connection between the regulator volume and an accumulation volume, movement of the switch ram in the activation direction being conditional upon flow of the hydraulic medium through the evacuation passage, so that the evacuation passage provides the hydraulic constriction, the flow regulator being mounted in the evacuation passage.

7 . The well tool of claim 1 , wherein the valve closing element is rotatable relative to the housing about a valve axis, the valve closing element configured for being switched between the open condition and the closed condition by angular displacement of the valve closing element about the valve axis.

8 . The well tool of claim 7 , wherein the valve closing element is generally tubular and is located co-axially in the housing, the valve axis being in alignment with a longitudinal axis of the housing, the valve closing element being configured to define a part of the internal bore of the tool assembly.

9 . The well tool of claim 7 , further comprising
a rotation mechanism to cause angular displacement of the switch ram about the longitudinal axis in response to longitudinal movement of the switch ram in the housing, wherein the switch ram is rotationally keyed to the valve closing element and is configured for reciprocating longitudinal movement relative to the housing,
to rotate the valve closing element to the open condition in response to hydraulically actuated longitudinal movement of the switch ram in the activating direction in response to above-threshold drilling fluid conditions, and
to rotate the valve closing element to the closed condition in response to longitudinal movement by the switch ram in an opposite return direction in response to subsequent cessation of the above-threshold drilling fluid conditions.

10 . The well tool of claim 9 , wherein the switch ram is longitudinally slidable relative to the valve closing element, the valve closing element having a fixed longitudinal position relative to the housing.

11 . The well tool of claim 1 further comprising a bias mechanism coupled to the switch ram and configured to exert a bias on the switch ram in a longitudinal return direction opposite to the activation direction, the bias mechanism being configured such that the bias matches or exceeds a hydraulic actuating force acting on the switch ram at below-threshold drilling fluid conditions, but is smaller than a hydraulic actuating force acting on the switch ram at above-threshold drilling fluid condition.

12 . A drilling installation comprising:
an elongate drill string extending longitudinally along a borehole, the drill string having a housing that defines a longitudinally extending internal bore configured to convey drilling fluid under pressure; a drill string tool forming part of the drill string and configured to be disposable between an activated condition and a deactivated condition; a control mechanism coupled to the drill string tool and configured to allow operator-controlled switching of the drill string tool by control of drilling fluid pressure conditions, the control mechanism comprising:
a valve body within the housing, the valve body defining a valve port in fluid communication with the internal bore and with a hydraulic deployment mechanism of the drill string tool;
a valve closing element configured for switching between an open condition in which the internal bore is in fluid communication with the activation volume, via the valve port, and a closed condition in which the closing element substantially prevents fluid flow through the valve port;
a switch ram coupled to the valve closing element and configured for hydraulically driven movement in an activation direction in response to predefined above-threshold downhole drilling fluid conditions, to switch the valve closing element from the open condition to the closed condition; and
a switch regulator coupled to the switch ram and configured to regulate switching of the valve closing element from the closed condition to the open condition by providing regulated hydraulic resistance to movement by the switch ram in the activation direction.

13 . The drilling installation of claim 12 , wherein the switch regulator comprises a switch timing mechanism configured to regulate a switching duration for hydraulically actuated movement of the valve closing element from the closed condition to the open condition in response to continuous exposure to above-threshold drilling fluid conditions, so that the switching duration is substantially independent of variations in the above-threshol

Assignees

• Halliburton Energy Services Inc

Inventors

• Galley Thomas Paul
• Winslow Daniel M

Classifications

• E21B21/10 Primary

  Valve arrangements in drilling-fluid circulation systems · CPC title

• E21B34/08 Primary

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

• E21B21/103 Primary

  Down-hole by-pass valve arrangements, i.e. between the inside of the drill string and the annulus (valves specifically for maintaining circulation of drilling fluid while connecting or disconnecting tubular joints E21B21/019) · CPC title

• E21B44/005

  Below-ground automatic control systems · CPC title

• E21B3/00

  Rotary drilling · CPC title