Method and Apparatus for Reducing Downhole Losses in Drilling Operations, Sticking Prevention, and Hole Cleaning Enhancement

Abstract

A downhole tool for use within a wellbore extending into an underground formation includes a wellbore wall disengaging assembly having a tubular string defining a longitudinal axis, and a plurality of longitudinal blades forming a retractable sleeve around the tubular string, the retractable sleeve having a substantially contiguous inner profile in a closed position, and wherein the retractable sleeve is actuated based on an internal pressure in the tubular string proximate to the downhole tool. A method of disengaging a downhole tool from a wall of a wellbore extending into an underground formation includes lowering a wellbore wall disengaging assembly, the assembly comprising a tubular string defining a longitudinal axis, and a plurality of longitudinal blades forming a retractable sleeve around the tubular string, the retractable sleeve having a substantially contiguous inner profile in a closed position, and actuating the retractable sleeve.

1 . A downhole tool for use within a wellbore extending into an underground formation, comprising:
 a wellbore wall disengaging assembly, comprising:   a tubular string defining a longitudinal axis; and   a plurality of longitudinal blades forming a retractable sleeve around the tubular string, the retractable sleeve having a substantially contiguous inner profile in a closed position, and wherein the retractable sleeve is actuated based on an internal pressure in the tubular string proximate to the downhole tool.   
     
     
         2 . The downhole tool of  claim 1 , wherein the retractable sleeve is mounted in coaxial relation to the tubular string. 
     
     
         3 . The downhole tool of  claim 1 , wherein the plurality of longitudinal blades of the retractable sleeve expand to a position with an increased internal diameter when the retractable sleeve is in an open position. 
     
     
         4 . The downhole tool of  claim 1 , wherein the retractable sleeve prevents a flow of a fluid in a lateral direction into the wellbore wall while in an open position, and permits the flow of the fluid in the lateral direction through at least one port in the closed position. 
     
     
         5 . The downhole tool of  claim 1 , wherein the retractable sleeve is configured to translate the longitudinal axis of the tubular string away from the wellbore wall in response to rotation of the retractable sleeve relative to the tubular string. 
     
     
         6 . The downhole tool of  claim 1 , wherein the wellbore wall disengaging assembly further comprises:
 a sensor for sensing pressure on the tubular string, and an actuator for receiving a pressure signal from the sensor and actuating the retractable sleeve.   
     
     
         7 . The downhole tool of  claim 6 , wherein the sensor is part of a cycling pressure mechanism. 
     
     
         8 . The downhole tool of  claim 6 , wherein the actuator is configured to move the plurality of longitudinal blades from the closed position to an open position and vice versa. 
     
     
         9 . The downhole tool of  claim 8 , wherein the actuation is aerodynamic or hydrodynamic in nature. 
     
     
         10 . The downhole tool of  claim 1 , wherein the outer surface of the longitudinal blades comprise a smooth or grooved configuration. 
     
     
         11 . The downhole tool of  claim 1 , wherein the tool is used for smearing a thief zone in a hydrocarbon well, and strengthening the wellbore to prevent downhole losses, pipe sticking, and improving the hole cleaning process. 
     
     
         12 . A method of disengaging a downhole tool from a wall of a wellbore extending into an underground formation, comprising:
 lowering a wellbore wall disengaging assembly, the assembly comprising a tubular string defining a longitudinal axis, and a plurality of longitudinal blades forming a retractable sleeve around the tubular string, the retractable sleeve having a substantially contiguous inner profile in a closed position; and   actuating the retractable sleeve based on an internal pressure in the tubular string proximate to the downhole tool.   
     
     
         13 . The method of  claim 12 , wherein the actuation is configured to move the plurality of longitudinal blades from the closed position to an open position. 
     
     
         14 . The method of  claim 13 , wherein the plurality of longitudinal blades of the retractable sleeve expand to a position with an increased internal diameter when the retractable sleeve is in an open position. 
     
     
         15 . The method of  claim 14 , further comprising:
 preventing a flow of a fluid in a lateral direction into the wellbore wall while in an open position; and   permitting the flow of the fluid in the lateral direction through at least one port in the closed position.   
     
     
         16 . The method of  claim 12 , further comprising:
 translating the longitudinal axis of the tubular string away from the wellbore wall in response to rotation of the retractable sleeve relative to the tubular string.   
     
     
         17 . The method of  claim 12 , wherein the wellbore wall disengaging assembly further comprises:
 a sensor for sensing pressure on the tubular string, and an actuator for receiving a pressure signal from the sensor and actuating the retractable sleeve.   
     
     
         18 . The method of  claim 12 , wherein the actuation is aerodynamic or hydrodynamic in nature. 
     
     
         19 . The method of  claim 12 , further comprising:
 smearing a thief zone in the hydrocarbon well; and   strengthening the wellbore to prevent downhole losses, pipe sticking, and improving the hole cleaning process.   
     
     
         20 . A downhole tool for use within a wellbore extending into an underground formation, comprising:
 a wellbore wall disengaging assembly, comprising:   a tubular string defining a longitudinal axis; and   a plurality of longitudinal blades forming a retractable sleeve around the tubular string, the retractable sleeve having a substantially contiguous inner profile in a first position, and wherein the plurality of longitudinal blades of the retractable sleeve expand to a position with an increased internal diameter when the retractable sleeve is in a second position.