Directional drilling control
Directional drilling tool apparatus and method
Distributed sensors-controller for active vibration damping...
Downhole weight control device for impact rock drilling tool
Drilling method and apparatus
Drilling system
Drilling tool for sinking wells in underground rock formations
Dual antenna radio frequency locating apparatus and method
Earth drilling apparatus with control valve
Fluid flow restrictor valve for a drill hole coring tool
Fluid pressure actuated by-pass and relief valve
Fluid pressure actuated bypass and pressure indicating relief va
Guided oscillatory well path drilling by seismic imaging
Long range electronic guidance system for locating a...
Macro assisted control system and method for a horizontal...
Macro assisted control system and method for a horizontal...
Mapping tool for tracking and/or guiding an underground...
Mapping tool for tracking and/or guiding an underground...
Mapping tool for tracking and/or guiding an underground...
Method and apparatus for automatic closed loop drilling system