The Lateral Steering Division of Wellbore Navigation, Inc. 'WELNAV' offers a complete steering-survey system which includes hardware, software, and field personnel to direct and monitor the course of a wellbore being laterally displaced from a point of entry.

    Crossings 'of under-rivers, under-streets, and under buildings are a special application of the standard WELNAV steering-survey probe system currently being used in directional drilling applications involving downhole motors on land and offshore.

    The WELNAV lateral steering system is ideally suited for applications where a point of entry and the point of exit have been defined (surveyed) because of the three axis sensor pack, precise calibration and self-contained software for surveys and drill collar inspection.

    WELNAV's sensor pack and software monitors the earth's magnetic field and enables comparisons of known magnetic intensities and dip angles in order to support the real time steering-survey data.

    Case histories show successful "crossings" involving passing under river barges, oil pipelines, storage tanks and exiting on target.

• Crossings drilled under a river for pipelines and/or cables.

• Pipes or cables laid underneath freeways without disrupting traffic.

• Placing cables underneath obstacles such as buildings, hills and lakes.

• Monitoring fractures in subsurface rock.

• Placing cables and pipes underground to protect environment with minimum disruption of surface.

• Running cables and pipes underground to protect environments and prevent disruptions due to rockslides.

• Determining orientations of core samples.