Inventors:
Larry G. Stolarczyk - Raton NM, 87740
Gerald L. Stolarczyk - Raton NM, 87740
International Classification:
G01S 1388
US Classification:
342 22, 342 61, 342 70, 342175, 342194, 342195, 342196, 702 2, 702 6, 702 9, 175 24, 175 26, 324332
Abstract:
A radar-plow drillstring steering system comprises a steering plow and a measurements-while-drilling instrument for mounting just behind the drill bit and downhole motor of a drill rod. The instrument includes a radar system connected to upward-looking and downward-looking horn antennas and a dielectric-constant sensor. The steering plow includes four pressure pads radially distributed around the outside surface and their associated servo motors. A coordinated control of the pressure pads allows the steering plow to push the drillstring and drill bit up-down-left-right. The antennas and sensor are embedded in respective ones of the pressure pads and are used to electronically and non-invasively probe a coal seam to locate its upper and lower boundary layers. The dielectric-constant sensor provides corrective data for the up and down distance measurements. Such measurements and data are radio communicated to the surface for tomographic processing and user display.