Patents by Inventor Randolf J. Sheffield

Randolf J. Sheffield 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).

  • Control line telemetry
    Patent number: 7493962
    Abstract: A system and method enable telemetry between a downhole device located in a wellbore and an uphole device. Electrical signals are communicated between locations via at least one fluid carrying control line. The control line provides a path for fluid flow as well as for the transmission of electrical signals. Thus, electrical signals may be transmitted from one location to another within a wellbore without separate electrical wires or cables.
    Type: Grant
    Filed: December 14, 2004
    Date of Patent: February 24, 2009
    Assignee: Schlumberger Technology Corporation
    Inventor: Randolf J. Sheffield
  • Plunger lift apparatus that includes one or more sensors
    Patent number: 7445048
    Abstract: A plunger lift apparatus includes wellhead equipment containing a receiver, a conduit extending from the wellhead equipment into a wellbore, and a plunger to be run through the conduit to a downhole location in the wellbore. The plunger includes at least a sensor to measure a downhole parameter, and a plunger is adapted to communicate the measured downhole parameter to the receiver.
    Type: Grant
    Filed: November 4, 2004
    Date of Patent: November 4, 2008
    Assignee: Schlumberger Technology Corporation
    Inventor: Randolf J. Sheffield