Shallow depth, coiled tubing horizontal drilling system

Abstract

The invention relates to a system for coiled tubing drilling of substantially horizontal shallow depth boreholes for installation of transmission or conveyance lines. A mobile platform mounts a coiled tubing reel and an adjustably mounted injector head. On the leading end of the coiled tubing is a drilling assembly, including a drill, a drill motor, a tracking device, and an orienter. Once the borehole has been drilled by pushing the drilling assembly through the borehole and exiting the earth's surface, a back reamer may be attached for enlarging the borehole as the coiled tubing is pulled back through the borehole. Once the borehole has been properly sized, the transmission or conveyance line may be attached to the leading end of the coiled tubing and the transmission or conveyance pipe pulled back through the borehole.

What is claimed is:  
     
         1 . A coiled tubing drilling and reaming apparatus for creating substantially horizontal, shallow depth boreholes beneath the earth's surface and for the installation of transmission or conveyance lines, said apparatus comprising: 
 a mobile platform;    a staging reel mounted on a first end of said mobile platform, said staging reel constructed and arranged for storage, spooling and unspooling of the coiled tubing;    a coiled tubing injector head for exerting both push and pull forces on the coiled tubing and for causing the coiled tubing to penetrate the earth's surface and moving the coiled tubing through the shallow depth borehole;    means for guiding the coiled tubing from said staging reel to the coiled tubing injector head;    means for adjustably mounting said coiled tubing injector head at an acute angle with respect to the earth's surface;    a drilling assembly for drilling a borehole through the earth, said drilling assembly being mounted on the end of the coiled tubing entering the borehole;    means for orienting said drilling assembly, said means for orienting said drilling assembly being co-located with said drilling assembly; and    means for back reaming the borehole to a diameter which allows for the pulling of the transmission or conveyance line therethrough when pull forces are being exerted on the coiled tubing.    
     
     
         2 . The coiled tubing drilling and reaming apparatus as defined in  claim 1  wherein said coiled tubing injector head is mounted on a second end of said mobile platform.  
     
     
         3 . The coiled tubing drilling and reaming apparatus as defined in  claim 1  wherein said mobile platform is wheeled.  
     
     
         4 . The coiled tubing drilling and reaming apparatus as defined in  claim 1  wherein said mobile platform is a self-propelled tracked vehicle.  
     
     
         5 . The coiled tubing drilling and reaming apparatus as defined in  claim 1  wherein said staging reel swivels on a horizontal axis.  
     
     
         6 . The coiled tubing drilling and reaming apparatus as defined in  claim 1  wherein said staging reel traverses from one side to another on a travel path substantially perpendicular to the long axis of the coiled tubing.  
     
     
         7 . The coiled tubing drilling and reaming apparatus as defined in  claim 1  wherein said staging reel is mounted to be vertically adjustable.  
     
     
         8 . The coiled tubing drilling and reaming apparatus as defined in  claim 1  wherein said drilling assembly includes a drill bit and a drill motor.  
     
     
         9 . The coiled tubing drilling and reaming apparatus as defined in  claim 8  wherein said drilling motor is a fluid motor and wherein fluid is supplied to said fluid motor through the coiled tubing.  
     
     
         10 . The coiled tubing drilling and reaming apparatus as defined in  claim 8  wherein said drilling motor is an electric motor.  
     
     
         11 . The coiled tubing drilling and reaming apparatus as defined in  claim 1  wherein the coiled tubing includes a wire line for controlling the operation of said drilling assembly.  
     
     
         12 . The coiled tubing drilling and reaming apparatus as defined in  claim 9  further including a gearbox.  
     
     
         13 . The coiled tubing drilling and reaming apparatus as defined in  claim 1  wherein said means for orienting said drilling assembly includes means for remotely changing the angular orientation of said drilling assembly with respect to the long axis of said borehole.  
     
     
         14 . The coiled tubing drilling and reaming apparatus as defined in  claim 1  further including means for tracking the location of said drilling assembly.  
     
     
         15 . The coiled tubing drilling and reaming apparatus as defined in  claim 14  wherein said means for tracking is selected from a group including GPS, radio signal, and sonic.  
     
     
         16 . The coiled tubing drilling and reaming apparatus as defined in  claim 1  wherein control of the dispensing and retraction of the coiled tubing from this staging reel is assisted by a tubing level winder.  
     
     
         17 . The coiled tubing drilling and reaming apparatus as defined in  claim 13  wherein said means for orienting is remotely controlled from above the earth's surface.  
     
     
         18 . The coiled tubing drilling and reaming apparatus as defined in  claim 17  wherein said remote control is provided by radio signals.  
     
     
         19 . The coiled tubing drilling and reaming apparatus as defined in  claim 17  wherein said remote control is provided by a wire line.  
     
     
         20 . A method for using coiled tubing to drill and backream a substantially horizontal shallow depth borehole through the earth for the placement of transmission or conveyance lines therein, said method comprising the steps of: 
 storing a length of coiled tubing on a storage reel;    unwinding the coiled tubing from said storage reel;    guiding one end of said length of coiled tubing from said storage reel to a coiled tubing injector head;    guiding the free end of said coiled tubing through said coiled tubing injector head;    attaching an orienting tool to the free end of said coiled tubing;    attaching a tracking device to said orienting tool;    attaching a drill bit and drill motor to said orienting tool;    inserting said drill bit, drill motor, orienting tool and tracking device through the earth's surface from above at an acute angle;    causing said drill bit, drill motor, orienting tool, tracking device, and the coiled tubing to be pushed through the earth in a first direction by said coiled tubing injector head and rotating said drill motor to create a substantially horizontal shallow depth borehole;    causing said drill bit, drill motor, orienting tool, and tracking device to pass back through the earth's surface from below;    causing an attached back reamer, said drill and drill motor, said guide tool, and the coiled tubing to be pulled through the earth in a second direction, opposite to said first direction, by said coiled tubing injector head to enlarge the substantially horizontal shallow depth borehole.    
     
     
         21 . The method as defined in  claim 20  wherein the unwinding of the coiled tubing from said storage reel is assisted by a level winder.  
     
     
         22 . The method as defined in  claim 20  wherein the unwinding of the coiled tubing from said storage reel is assisted by laterally traversing said storage reel.  
     
     
         23 . The method as defined in  claim 20  wherein said acute angle of insertion is controlled by the angular position of said coiled tubing injector head.  
     
     
         24 . The method as defined in  claim 20  wherein said orienting tool is remotely controlled from a position above the earth's surface.  
     
     
         25 . The method as defined in  claim 20  wherein said storage reel and said coiled tubing insertion tool are mounted on separate platforms.  
     
     
         26 . The method as defined in  claim 20  wherein said borehole is backreamed with an enlarged bit following the pushing of the coiled tubing in a first direction and while the coiled tubing is being pulled in a second direction.  
     
     
         27 . The method as defined in  claim 20  wherein a transmission or conveyance line is pulled in said second direction through the borehole.  
     
     
         28 . The method as defined in  claim 20  wherein the coiled tubing is left in the borehole to become a transmission or conveyance line.  
     
     
         29 . A system for creating a substantially horizontal shallow depth borehole lined by a transmission or conveyance line through the earth, said system comprising: 
 a coiled tubing drill string having a leading end;    a reel assembly for winding, storing, and unwinding said coiled tubing drill string;    a drilling assembly mounted to the leading end of said coiled tubing drill string, said drilling assembly including a tracking device, a drill motor, and a drill bit;    an injector head for guiding said coiled tubing drill string into the borehole at an acute angle to the earth's surface, for pushing said coiled tubing through the earth and to exit the earth's surface, for pulling said coiled tubing from the borehole, and for lining the borehole with a transmission or conveyance line;    a connector for connecting said transmission or conveyance pipe to the leading end of the coiled tubing drill string to enable the transmission or conveyance pipe to be drawn into the borehole as said coiled tubing is pulled from the borehole.    
     
     
         30 . The system as defined in  claim 29  wherein said reel and said injector head are mounted on a mobile platform.  
     
     
         31 . The system as defined in  claim 29  wherein said mobile platform is a wheeled trailer.  
     
     
         32 . The system as defined in  claim 29  wherein said mobile platform is a tracked vehicle.  
     
     
         33 . The system as defined in  claim 29  wherein said drill bit is replaced with an enlarging back reamer when said transmission or conveyance line is pulled back through the borehole.