New Concepts for Vertical Drilling of Boreholes

Abstract

ABSTRACT Directional drilling equipment has been developing from conventional whipstock rotary assemblies over downhole motors with bent housing to navigational motors. A self-contained downhole automatic closed loop system is recognized as being the next major development milestone. As a first step such a drilling tool which automatically compensates for any deviation from the vertical direction has been introduced within the German scientific super-deep drilling project KTB. Technical function of the tool as well as recent field experience is reported.