Patents by Inventor Robert E. Sheffield

Robert E. 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).

  • Repair of shallow casing leaks in oil wells
    Patent number: 4538684
    Abstract: Method of repairing a leak in a well production string by milling a protective pipe string down between the conductor pipe and the production string, and cementing it in place at depths up to 500 feet.
    Type: Grant
    Filed: April 9, 1984
    Date of Patent: September 3, 1985
    Assignee: Shell Western F&P Inc.
    Inventor: Robert E. Sheffield
  • Method for optimizing the position of a furnace damper without flue gas analyzers
    Patent number: 4054408
    Abstract: A process for optimizing the combustion of fuel in a furnace wherein the total weight of carbon and hydrogen in the fuel is determined and from the total weight of hydrogen and carbon the air required for combustion can be computed with the air flow to the furnace being adjusted to provide the combustion air plus the desired excess oxygen. The efficiency of the furnace versus excess oxygen is determined and the excess oxygen is varied a small amount on each side of the optimum point obtained from the efficiency versus excess oxygen determination to continuously verify the optimum point.
    Type: Grant
    Filed: August 30, 1976
    Date of Patent: October 18, 1977
    Assignee: Shell Oil Company
    Inventors: Robert E. Sheffield, Robert L. Chew, Charles R. Cutler