Patents Assigned to Washington Rotating Control Heads
  • Drilling head method and apparatus
    Patent number: 4531591
    Abstract: A rotary drilling head wherein rotary friction between the rotary spindle assembly and the spindle housing is limited by improvements in bearing and seal lubrication and by seal structure such that the gripping action of a resiliently flexible packer on a drill string provides a rotary drive connection sufficient to impart rotation to the spindle assembly through rotation of the drill string.
    Type: Grant
    Filed: August 24, 1983
    Date of Patent: July 30, 1985
    Assignee: Washington Rotating Control Heads
    Inventor: Vaughn R. Johnston