Automatic Control System For Connecting A Dual-Member Pipe

Abstract

A system and method of making up and breaking out a dual-member drill string. The system comprises a spindle, a spindle carriage and a drive frame. The drive frame provides thrust to the spindle, while the spindle carriage provides rotation. The spindle has an outer spindle and an inner spindle, and is adapted to connect to a pipe section having an outer pipe section and an inner pipe section. Inner joints are geometrically shaped, while outer joints are threaded. When making up dual member drill string, the spindle is advanced, with the outer spindle rotating, and the inner spindle rotating in alternating directions, or “dithering.” A float sensor and a processor are used in tandem to cooperatively couple the inner spindle with the inner pipe sections and the outer spindle with the outer pipe sections.

1 . A drill string make-up system comprising:
 a drive frame;   a spindle comprising an inner spindle and an outer spindle connectable to a pipe section having an inner pipe section and an outer pipe section;   a means for providing thrust and rotation to both the inner spindle and outer spindle, wherein the inner spindle is rotatable and thrustable independent of the outer spindle; and   a float sensor to indicate a float position of the inner spindle; and   a processor to generate a request for thrust or rotation of the inner spindle in response to signals from the float sensor.   
     
     
         2 . The system of  claim 1  wherein the inner pipe section comprises a threaded connection. 
     
     
         3 . The system of  claim 1  wherein the inner pipe section comprises a geometrically formed torque-transmitting slip fit connection. 
     
     
         4 . The system of  claim 3  wherein the geometrically formed slip fit connection comprises a hexagonal joint. 
     
     
         5 . The system of  claim 1  wherein the processor automatically controls rotation of the inner spindle over less than 360 degrees in alternating clockwise and counterclockwise directions in response to the float signal. 
     
     
         6 . A horizontal boring machine comprising a makeup/breakout system, the makeup/breakout system comprising:
 a drive frame;   a spindle comprising an inner spindle and an outer spindle connectable to a pipe section having an inner pipe section and an outer pipe section;   a carriage supported on the drive frame to provide thrust and rotation to both the inner spindle and the outer spindle, wherein the inner spindle is rotatable and thrustable independent of rotation and thrust of the outer spindle;   a float sensor to determine the amount of float between the carriage and the drive frame and to transmit a float signal indicating the inner spindle has not coupled with the inner pipe section; and   a processor to receive the float signal and to adjust the inner spindle and outer spindle in response to the float signal.   
     
     
         7 . The system of  claim 6  wherein the float sensor comprises centering springs. 
     
     
         8 . The system of  claim 6  wherein the float sensor comprises:
 a sensor rod secured to the drive frame; 
 a magnet secured to the carriage and positioned to move along the sensor rod as the carriage floats relative to the drive frame; and 
 a circuit to determine the position of the magnet along a length of the sensor rod and transmit the float signal to the processor. 
 
     
     
         9 . An HDD system comprising:
 a drilling machine;   a carriage supported on the drilling machine, the carriage comprising an inner spindle and an outer spindle; and   a drill string comprising an inner member operatively connectable to the inner spindle and an outer member operatively connectible to the outer spindle; and   a processor to command the carriage to connect the inner member of the drill string to an inner member of a pipe section;   a float sensor supported by the drilling machine to detect a carriage float position indicative of whether the inner member of the pipe section connected to the inner spindle is coupled to the inner member of the drill string and to transmit a float signal to the processor.   
     
     
         10 . The system of  claim 9  further comprising a downhole tool operatively connected to an end of the drill string. 
     
     
         11 . The system of  claim 10  wherein the downhole tool comprises a directional drilling tool. 
     
     
         12 . The system of  claim 10  wherein the downhole tool comprises a bent sub used to deflect the drill, bit from a linear path. 
     
     
         13 . The system of  claim 9  wherein the float sensor comprises:
 a sensor rod secured to the drive frame; 
 a magnet secured to the carriage and positioned to move along the sensor rod as the carriage floats relative to the drive frame; and 
 a circuit to determine the position of the magnet along a length of the sensor rod and transmit the float signal to the processor. 
 
     
     
         14 . The system of  claim 9  wherein the float sensor comprises an electromagnetic position sensor. 
     
     
         15 . The system of  claim 9  further comprising a pipe handling system adapted to load the pipe section into the carriage. 
     
     
         16 . The system of  claim 9  wherein the processor further commands the carriage to connect the outer member of the drill string to an outer member of a pipe section. 
     
     
         17 . The system of  claim 9  wherein the processor further commands the carriage to connect the inner member of a pipe section to the inner spindle.