Patents by Inventor John A. McCullagh

John A. McCullagh has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Drilling system with drill string valves
    Patent number: 8307913
    Abstract: A method to control borehole fluid flow includes detecting a drilling condition and operating at least one valve in the drill string to place an exterior of the drill string in fluid communication with an interior of the drill string in response to detecting the drilling condition.
    Type: Grant
    Filed: May 1, 2008
    Date of Patent: November 13, 2012
    Assignee: Schlumberger Technology Corporation
    Inventors: Lee F. Dolman, Benjamin P. Jeffryes, Ashley B. Johnson, Brian Clark, John A. McCullagh
  • DRILLING SYSTEM WITH DRILL STRING VALVES
    Publication number: 20090272580
    Abstract: A method to control borehole fluid flow includes detecting a drilling condition and operating at least one valve in the drill string to place an exterior of the drill string in fluid communication with an interior of the drill string in response to detecting the drilling condition.
    Type: Application
    Filed: May 1, 2008
    Publication date: November 5, 2009
    Applicant: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventors: Lee F. Dolman, Benjamin P. Jeffryes, Ashley B. Johnson, Brian Clark, John A. McCullagh