HORIZONTAL DIRECTIONAL DRILLING IN WELLS

摘要

A method and apparatus for horizontally drilling in wells utilizing a shoe assembly (5) at the down hole end of upset tubing (52). The shoe assembly (5) includes a fixed section (10) and a rotatable section (11) suspended below the fixed section (10). An electric motor (57) and associated batteries (13) and a gyroscope (36) carried on the rotatable section (11) enable an operator on the surface to selectively rotate and position the rotatable section (11) to any desired angular location for drilling a hole in the well casing (20). After one or more holes have been cut in the casing (20), a drill assembly (12) can be removed from the upset tubing (52) and be replaced by a high pressure blaster nozzle to bore into the formation zones. The gyroscope (36) enables the operator to accurately position the rotatable section (11) to the same locations at which the holes have been cut. The drill assembly (12) includes an electric motor (57) with an associated battery (13), flexible drive shaft (59), and a hole saw (61).