Methods for cuttings for a wireline drilling tool

Abstract

A method of removing cuttings from a workfront of a lateral borehole hole being drilled from a main borehole by a drilling tool is provided. The drilling tool comprising a tool body including a motor, an axial drive mechanism for advancing the tool body in the well, and a drill bit powered by the motor for drilling the underground formation at the workface and producing cuttings as the tool is advanced. The drilling tool is preferably connected to the surface by means of a cable extending through the lateral borehole and main borehole. The method independently comprising transporting the drilled cuttings from the workface to the part of the lateral borehole immediately behind the drilling tool. Transporting the drilled cuttings from immediately behind the drilling tool to the junction of the lateral borehole and the main well. And transporting the cuttings from the junction to a place of disposal.

1 . A method of removing cuttings from a workfront of a lateral borehole hole being drilled from a main borehole by a drilling tool comprising a tool body including a motor, an axial drive mechanism for advancing the tool body in the well, and a drill bit powered by the motor for drilling the underground formation at the workface and producing cuttings as the tool is advanced, wherein the drilling tool is connected to the surface and powered by means of a cable extending through the lateral borehole and main borehole, the method comprising:
 transporting the drilled cuttings from the workface to the part of the lateral borehole immediately behind the drilling tool;   transporting the drilled cuttings from immediately behind the drilling tool to the junction of the lateral borehole and the main well; and   transporting the cuttings from the junction to a place of disposal;   
       wherein the steps of transporting around the drilling tool, transporting from the drilling tool to the junction and transporting from the junction to the place of disposal are all independent of each other. 
     
     
         2 . A method as claimed in  claim 1 , wherein the lateral borehole is filled with a fluid, at least part of which is circulated through the drilling tool during drilling. 
     
     
         3 . A method as claimed in  claim 2 , wherein transport of the drilled cuttings past or through the drilling tool includes transport by local fluid circulation. 
     
     
         4 . A method as claimed in  claim 1 , wherein the motion of the tool body is used to move the cuttings. 
     
     
         5 . A method as claimed in  claim 4 , comprising providing the outer surface of the tool body with a thread formation and rotating the body to move the cuttings by the action of the thread. 
     
     
         6 . A method as claimed in  claim 4 , wherein other formations or appendages are provided on the tool body and moved to move the cuttings. 
     
     
         7 . A method as claimed in  claim 4 , comprising deforming the tool body to create a peristaltic wave to move the cuttings. 
     
     
         8 . A method as claimed in  claim 1 , wherein transport of the cuttings from behind the tool to the junction with the main borehole includes creating an asymmetric pulsatile flow in the lateral borehole to drive the cuttings to the junction. 
     
     
         9 . A method as claimed in  claim 8 , wherein the pulsatile flow is created using the drilling tool. 
     
     
         10 . A method as claimed in  claim 1 , wherein transport to the junction is performed by drilling the formation underbalanced so as to create a net flow of well fluids back towards the main borehole. 
     
     
         11 . A method as claimed in  claim 10 , wherein the underbalance is created by a periodic burst of gas that allows the overall rockface pressure to be maintained at over or near balance, but helps increase transport velocities in the borehole. 
     
     
         12 . A method as claimed in  claim 1 , wherein the tool body is provided with a tail pipe extending back along the lateral borehole, the cuttings being transported by pumping them along the tail pipe. 
     
     
         13 . A method as claimed in  claim 1 , wherein cuttings are transported to the, junction by withdrawing the drilling tool from the lateral well so as to push the cuttings back to the junction. 
     
     
         14 . A method as claimed in  claim 1 , wherein one or more separate transport devices are provided between the drilling tool and the junction which are shuttled back and forth carrying the cuttings away from the drilling tool. 
     
     
         15 . A method as claimed in  claim 1 , wherein flow back to the junction is created chemically 
     
     
         16 . A method as claimed in  claim 15 , wherein flow is created by igniting propellant charges behind the drilling tool. 
     
     
         17 . A method as claimed in  claim 1 , wherein transport away from the junction includes allowing the cuttings to fall into a lower section of the main borehole. 
     
     
         18 . A method as claimed in  claim 17 , wherein the cuttings are allowed to fall into a collector which is later removed from the well. 
     
     
         19 . A method as claimed in  claim 17 , wherein the cuttings are later cleaned out via a secondary or plurality of tubing(s) passed into the well from the surface.