DRILL HEAD STEERING

摘要

A method of steering a fluid drilling head in an underground borehole drilli ng situation is provided by rotating the flexible hose through which high pressure is provided to the drilling head and providing a biasing force on t he drilling head. The hose can be rotated from a remote surface mounted situati on by rotating the entire surface rig (13) in a horizontal plane about a turntable (24) causing the vertically orientated portion of the hose (11) to rotate about its longitudinal axis. The biasing force can be provided in a number of different ways but typically results from the use of an asymmetric al gauging ring on the fluid drilling head.