Drilling tool, apparatus and method for underreaming and simultaneously monitoring and controlling wellbore diameter

Abstract

The Smart Reamer® Tool, Apparatus or Method is used to underream an oil or natural gas well while interlinked calipers and calibration sensors simultaneously record data relating to the geometry of the drilling operation (well diameter, diameter of the underreamed zone) and drilling fluid properties (density). Further sensors provide data on the relative position of the cutting and stabilizing blocks. Other sensors measure vibration data. All the sensors are interlinked by means of microprocessors which compare and correlate said data to automatically verify and deliver a desired wellbore diameter without the need to unnecessarily stop drilling or trip out of the hole.

What is claimed is: 
     
         1 . An underreaming tool comprising a tool body and at least one cutter block carrying a plurality of cutter elements directed outwardly of the tool body, wherein the cutter block is received within the tool body in a cutter block chamber having an open mouth and means for extending the cutter block from the chamber through the chamber mouth with the cutter elements projecting from the tool body, and for retracting the cutter block back into the chamber. 
     
     
         2 . The at least one cutter block of  claim 1  comprising a magnetic strip or sensor to detect a cutter block position. 
     
     
         3 . The said tool body of  claim 1  comprising a magnetic strip or sensor to detect a cutter block position. 
     
     
         4 . The tool of  claim 1  with an internal duct open to a source of drilling fluid to an external nozzle among the cutter elements and movable with said block. 
     
     
         5 . The magnetic cutter position sensor of  claim 2  further detecting a magnetic signal increasing or decreasing in strength 
     
     
         6 . The magnetic cutter position sensor of  claim 2  further detecting an aligned or misaligned magnetic signal. 
     
     
         7 . The magnetic cutter position sensor of  claim 2  further detecting the mechanical expansion or retraction of said extendable block position 
     
     
         8 . The tool of  claim 1  further comprising an axial internal through passage flow of drilling fluid. 
     
     
         9 . The of  claim 1  further comprising said position sensor connected to a sealed chamber wherein position sensor provides a mechanical alignment signaling block position, a vibration sensor and wherein block positional data is compared with vibration data. 
     
     
         10 . The tool of  claim 2  comprising an internal duct open to a source of drilling fluid communicable with an nozzle. 
     
     
         11 . The tool of  claim 1  further comprising pressure compensation to the wellbore. 
     
     
         12 . The tool of  claim 1  further comprising a mechanical locking collet finger which can be located into one of a plurality of retaining lip grooves by travelling lock which is located by sealing collar. 
     
     
         13 . The at least one cutter block of  claim 1  carrying a plurality of cutter elements directed outwardly of the tool body wherein a seal is provided around the cutter block at the mouth of the receiving chamber. 
     
     
         14 . The cutter block of  claim 13  further within a sealed chamber the body 
     
     
         15 . The tool of  claim 1  in contact with a surface decoder. 
     
     
         16 . The tool of  claim 2  further comprising determining said cutter block extension length and position.