Earth boring device and method of use

Abstract

A borehole tool for drilling in a formation is disclosed. The tool is of the type that incorporates a sphere for deploying cutting elements for hydraulically expanding the same for borehole reaming or enlargement during drilling. The tool conveniently includes a reset function where the cutting elements can be reset to a retracted position within the cutter housing. Advantageously the reset of the cutter elements is achievable by simply removing a cutting bit at the end of drill string and inserting the reset member in the form of a elongate rod through the end of the drill string to urge the sphere or ball back to the top of the drill string for retrieval and resetting the movable member which allows for fluid flow redirection within the cutter housing. The reset function can be achieved on site thus avoiding significant expenses and downtime typically associated with systems that cannot be reset onsite.

We claim: 
     
         1 . An expandable reamer apparatus for subterranean drilling, comprising:
 a tubular body having a longitudinal axis and a trailing end for connecting to a drill string;   fluid pressure actuable cutting members movable from a storage position retracted within said tubular body to a use position extending outwardly of said tubular body for reaming and/or expanding the diameter of a borehole;   a drilling fluid flow redirection member movably mounted within said tubular body from a first inactive position to a second active position where fluid is redirected adjacent said fluid pressure actuable cutting members to actuate said cutting members to said use position.   
     
     
         2 . The apparatus as set forth in  claim 1 , wherein said drilling fluid flow direction member is coaxially disposed within said tubular body. 
     
     
         3 . The apparatus as set forth in  claim 1 , wherein said apparatus includes an annulus tube. 
     
     
         4 . The apparatus as set forth in  claim 3 , wherein said annulus tube is in fluid communication with said cutting members. 
     
     
         5 . The apparatus as set forth in  claim 4 , wherein said apparatus includes a coaxially disposed receiving tube for receiving said flow redirection member and redirecting flow to said annulus tube. 
     
     
         6 . The apparatus as set forth in any one of  claim 1 , wherein said apparatus includes an actuator for actuating said drilling fluid flow redirection member. 
     
     
         7 . The apparatus as set forth in  claim 6 , wherein said actuator comprises a solid sphere. 
     
     
         8 . The apparatus as set forth in  claim 1 , wherein said drilling fluid flow redirection member is resettable from said active position to said inactive position. 
     
     
         9 . The apparatus as set forth in  claim 8 , further including a reset member for effecting movement of said drilling fluid flow redirection member from said active position to said inactive position. 
     
     
         10 . The apparatus a set forth in any one of  claim 1 , wherein said drilling fluid flow redirection member is disposed coaxially within said body adjacent said fluid pressure actuable cutting members. 
     
     
         11 . The apparatus a set forth in any one of  claim 10 , wherein said drilling fluid flow redirection member comprises a collet sleeve having a plurality of openings. 
     
     
         12 . The apparatus a set forth in  claim 1 , wherein said cutting members are manually or self resettable. 
     
     
         13 . A method for reaming a borehole in a subterranean formation, comprising:
 positioning an expandable reaming apparatus within a subterranean formation, said reaming apparatus having a tubular body, a drilling fluid flow path extending through said tubular body, fluid pressure actuable cutting members movable from a storage position retracted within said body to a use position extending outwardly of said tubular body for reaming and/or expanding the diameter of a borehole;   introducing drilling fluid into said reaming apparatus;   redirecting said drilling fluid flow in said reaming apparatus with a redirection member movably mounted within said tubular body from a first inactive position to a second active position distal from said cutting members to facilitate drilling fluid flow redirection whereby drilling fluid pressure actuates said cutting members to said use position; and   reaming or expanding an expanded borehole in said formation with said apparatus.   
     
     
         14 . The method as set forth in  claim 13 , wherein said redirection member in said inactive position is adjacent said cutting members. 
     
     
         15 . The method as set forth in  claim 13 , wherein said redirection member in said inactive position is distal from said cutting members. 
     
     
         16 . The method as set forth in  claim 13 , further including the step of actuating said redirecting member with an actuating member. 
     
     
         17 . The method as set forth in  claim 16 , wherein actuating includes positioning a solid sphere at one end of said apparatus. 
     
     
         18 . The method as set forth in  claim 13 , further including the step of resetting said redirection member. 
     
     
         19 . The method as set forth in  claim 18 , wherein resetting includes urging said redirection member from said active position to said inactive position with an elongate member. 
     
     
         20 . The method as set forth in  claim 16 , wherein said cutting members are manually or self resettable.