Actuation system and method for a downhole tool

Abstract

An actuation system and method for a downhole tool. The downhole tool includes a body having an axial bore extending at least partially therethrough and a chamber disposed radially-outward from the bore. A valve is disposed within the bore and adapted to move between a first position which prevents fluid flow from the bore to the chamber through a port and a second position which permits the fluid flow from the bore to the chamber through the port. A motor, disposed within the bore, is adapted to move the valve between the first and second positions. An actuatable component of the downhole tool, e.g., a cutter block of an underreamer downhole tool, is movably coupled to the body and adapted to move from a non-actuated state to an actuated state in response to fluid flow through the port into the chamber.

What is claimed is: 
     
         1 . A downhole tool having an actuation system, comprising:
 a body having a bore axially extending at least partially therethrough, a chamber disposed radially-outward from the bore and being in fluid communication with the bore through a port;   a valve disposed within the bore and adapted to move between a first position in which the valve prevents fluid flow from the bore to the chamber through the port and a second position in which the valve permits the fluid to flow from the bore to the chamber through the port;   a motor disposed within the bore and adapted to move the valve between the first position and the second position; and   an actuatable component movably coupled to the body, the actuatable component adapted to move from a non-actuated state to an actuated state in response to fluid flow into the chamber through the port.   
     
     
         2 . The downhole tool of  claim 1 , wherein the valve is arranged and designed to move axially within the bore between the first position and the second position. 
     
     
         3 . The downhole tool of  claim 1 , further comprising a conversion assembly coupled between the motor and the valve that converts rotary motion of the motor into axial motion of the valve. 
     
     
         4 . The downhole tool of  claim 1 , wherein the motor is arranged and designed to rotate the valve about a longitudinal axis extending through the valve. 
     
     
         5 . The downhole tool of  claim 4 , wherein the valve comprises a finger arranged and designed to align with the port when the valve is in the first position and to be offset from the port when the valve is in the second position. 
     
     
         6 . The downhole tool of  claim 4 , wherein the valve has an opening formed radially therethrough, the opening arranged and designed to be offset from the port when the valve is in the first position and aligned with the port when the valve is in the second position. 
     
     
         7 . The downhole tool of  claim 1 , further comprising an actuating member responsive to hydraulic pressure of fluid flow into the chamber, the actuating member arranged and designed to move the actuatable component from the non-actuated state to the actuated state in response to increased hydraulic pressure due to fluid flow into the chamber. 
     
     
         8 . The downhole tool of  claim 1 , further comprising a position sensor system disposed at least partially within the bore and adapted to measure an axial position of the actuatable component. 
     
     
         9 . The downhole tool of  claim 8 , wherein the position sensor system includes:
 at least one magnet coupled to the actuatable component; and   a probe disposed within the bore, the probe having a plurality of magnetometers arranged along an axial length thereof.   
     
     
         10 . The downhole tool of  claim 9 , wherein the plurality of magnetometers is arranged along an axial length of at least two boards disposed within the probe. 
     
     
         11 . The downhole tool of  claim 8 , further comprising a telemetry system disposed within the bore, the telemetry system arranged and designed to transmit a signal representative of the axial position of the actuatable component to a remote location. 
     
     
         12 . The downhole tool of  claim 8 , wherein the actuatable component engages and moves a mandrel, the axial position of the mandrel representative of the state of the actuatable component. 
     
     
         13 . The downhole tool of  claim 1 , wherein the downhole tool is an underreamer. 
     
     
         14 . A well tool actuation system for use in a wellbore, comprising:
 a valve disposed within an internal flow passage of a downhole tubular and arranged and designed to move between a first position sealing a port in an inner wall of the downhole tubular and a second position permitting fluid flow from the internal flow passage into the port, the valve having one or more passages therethrough to permit fluid to pass axially therethrough to a downhole drill bit regardless of the valve position; and   a motor disposed within the internal flow passage of the downhole tubular to permit fluid in the internal flow passage to pass therearound, the motor coupled to the valve and arranged and designed to move the valve between the first position and the second position.   
     
     
         15 . The well tool actuation system of  claim 14 , further comprising a downhole receiver coupled to the motor and adapted to receive a signal from a remote location, the signal controlling one or more operations of the motor to move the valve between the first position and the second position. 
     
     
         16 . The well actuation system of  claim 14 , wherein the valve is arranged and designed to move axially within the internal flow passage between the first position and the second position. 
     
     
         17 . The well actuation system of  claim 16 , further comprising a conversion assembly coupled between the motor and the valve that converts rotary movement of a shaft of the motor into axial movement of the valve. 
     
     
         18 . The well actuation system of  claim 14 , wherein the motor is arranged and designed to rotate the valve about a longitudinal axis extending through the valve. 
     
     
         19 . The well actuation system of  claim 18 , wherein the valve is arranged and designed to seat in the first position in response to a pressure differential generated between the internal flow passage and the wellbore when fluid passes through the one or more passages of the valve. 
     
     
         20 . The well actuation system of  claim 14 , further comprising a position sensor system disposed at least partially within the internal flow passage and adapted to measure an axial position of an actuatable component. 
     
     
         21 . The well actuation system of  claim 20 , further comprising a telemetry system disposed within the internal flow passage, the telemetry system arranged and designed to transmit a real time signal representative of the axial position of the actuatable component to a remote location. 
     
     
         22 . The well actuation system of  claim 14 , wherein the valve and motor are modular and may be individually deployed and retrieved from surface to a downhole location of the wellbore. 
     
     
         23 . The well actuation system of  claim 14 , wherein the motor is coupled to the valve through a self-aligning coupling. 
     
     
         24 . A method for actuating a downhole tool, comprising:
 transmitting a signal from a surface location to a downhole receiver disposed in a downhole tool, the signal controlling one or more operations of a motor disposed within a bore that extends axially at least partially through a body of the downhole tool, the motor coupled to and moving a valve disposed within the bore between a first position and a second position, the valve preventing fluid flow through a port disposed between the bore and a chamber disposed radially-outward from the bore when the valve is in the first position and the valve permitting fluid flow from the bore into the chamber through the port when the valve is in the second position, the fluid flow into the chamber causing hydraulic pressure to increase within the chamber thereby actuating an actuatable component of the downhole tool; and   operating the downhole tool while the actuatable component of the downhole tool is actuated.   
     
     
         25 . The method of  claim 24 , wherein a conversion assembly coupled between the motor and the valve converts rotary movement of a shaft of the motor to axial movement of the valve. 
     
     
         26 . The method of  claim 24 , further comprising measuring an axial position of the actuatable component with a position sensor system disposed at least partially within the bore. 
     
     
         27 . The method of  claim 26 , further comprising transmitting the axial position of the actuatable component to the surface location via a telemetry system disposed within the bore. 
     
     
         28 . The method of  claim 27 , wherein the transmitting is conducted via a telemetry method selected from the group consisting of pressure pulse, acoustic waves, electromagnetic waves and insulated conductor.