Intelligent Debris Removal Tool

Abstract

A debris removal tool uses a screen to separate the debris coming into the tool from the moving fluid. The fluid that gets through the screen then operates a flow sensing device that is preferably a turbine whose speed of rotation or other characteristics of its movement generates a signal that is picked up by the measurement while drilling tool and conveyed to the surface. The surface personnel first respond by turning off surface pumps to allow debris to fall by gravity off the clogged screen. If that fails, the tool is pulled through the well fluid inducing a reverse flow through the screen to get the debris blocking it to go back into the well through the debris removal tool inlet.

1 . A method of operating a debris removal tool in a wellbore comprising:
 moving fluid downhole to direct debris into a downhole debris catcher;   separating debris from said moving fluid with a screen;   sensing a change in flow through said debris catcher;   getting a signal at a surface location regarding said change in flow;   stopping fluid movement through said debris catcher in response to said signal.   
     
     
         2 . The method of  claim 1 , comprising:
 pulling said debris catcher uphole.   
     
     
         3 . The method of  claim 2 , comprising:
 pulling said debris catcher uphole after stopping said fluid movement.   
     
     
         4 . The method of  claim 2 , comprising:
 pulling said debris catcher uphole before stopping said fluid movement.   
     
     
         5 . The method of  claim 1 , comprising:
 sensing flow with a turbine flow sensor.   
     
     
         6 . The method of  claim 1 , comprising:
 sensing flow indirectly by measuring a parameter different than flow.   
     
     
         7 . The method of  claim 6 , comprising:
 measuring vibration as a way of determining flow.   
     
     
         8 . The method of  claim 1 , comprising:
 sensing flow downstream of said screen.   
     
     
         9 . The method of  claim 8 , comprising:
 placing a flow sensing device between said screen and an eductor that draws fluid through said screen.   
     
     
         10 . The method of  claim 1 , comprising:
 sending a signal from a flow sensor is said debris catcher to a measurement while drilling device;   relaying a signal from said measurement while drilling device to the surface.   
     
     
         11 . The method of  claim 10 , comprising:
 manually turning off a pump that moves fluid in said debris catcher in response to a predetermined change in said relayed signal.   
     
     
         12 . The method of  claim 10 , comprising:
 using a controller at the surface to automatically turn off a surface pump that moves fluid in said debris catcher in response to a predetermined change in said relayed signal.   
     
     
         13 . The method of  claim 1 , comprising:
 positioning said screen over a debris storage volume in said debris catcher;   allowing debris on said screen to fall into said volume when pumped fluid movement through said debris catcher is stopped.   
     
     
         14 . The method of  claim 13 , comprising:
 picking up said debris catcher after said stopping of said fluid movement through said debris catcher.   
     
     
         15 . The method of  claim 13 , comprising:
 picking up said debris catcher before said stopping of said fluid movement through said debris catcher.   
     
     
         16 . The method of  claim 13 , comprising:
 picking up said debris catcher at the same time as said stopping of said fluid movement through said debris catcher.