Patents by Inventor John M. Elsen

John M. Elsen 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 fluid additives for use in hard brine environments
    Patent number: 4743383
    Abstract: A drilling fluid additive is disclosed which will prevent water loss into subterranean formations during the drilling of oil and gas wells in hard brine environments. The drilling fluid additive comprises a hydrocarbon, an anionic surfactant, an alcohol, a sulfonated asphalt, a biopolymer, and optionally an organophilic clay, poly(N-vinyl-2-pyrrolidone-co-sodium-2-acryamido-2-methylpropane sulfonate, and water.
    Type: Grant
    Filed: November 24, 1986
    Date of Patent: May 10, 1988
    Assignee: Phillips Petroleum Company
    Inventors: Wayne S. Stewart, George G. Dixon, John M. Elsen, Billy L. Swanson