Patents Assigned to Prad Research and Development NV
  • Method of drilling a directonal well bore
    Patent number: 4715452
    Abstract: The invention relates to a method of drilling a directional well bore with a drill string. According to the invention, at least a part of the trajectory of the well bore is drilled with a constant build rate so that the part has substantially a constant curvature shape.
    Type: Grant
    Filed: January 7, 1986
    Date of Patent: December 29, 1987
    Assignee: Prad Research and Development NV
    Inventor: Michael Sheppard