Patents by Inventor Ljerka Kondres

Ljerka Kondres 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).

  • Thread compound developed from solid grease base and the relevant preparation procedure
    Patent number: 5885941
    Abstract: A new thread compound for tubing, casing and sucker rods which is composed of: mineral oil (freezing point in the range from -10.degree. to -14.degree. C.), polyisobutene solution (Staudinger index J.sub..degree. 46 to 52) in mineral oil, anticorrosive additive based on organic compounds, which do not contain heavy metals and chlorinated hydrocarbons, and which is dissolved in mineral oil, modified alumino-silicate as trialkylaryl ammonium smectite, propylene carbonate density/20.degree. C. 1.189, aluminium stearate (ash from 9.5 to 11.5 wgt. parts), graphite (quality as required in API 5A3), copper flake (quality as required in API 5A3), lead powder (quality as required in API 5A3) and zinc dust (quality as required in API 5A3), and a process for its manufacture are provided.The thread compound is characterized by high resistance to temperature, pressure, extreme friction and wear.
    Type: Grant
    Filed: November 4, 1997
    Date of Patent: March 23, 1999
    Assignee: "IVASIM" d.d. Za proizvodnju kemijskih proizvoda
    Inventors: Milka Sateva, Marija Koren-Markovic, Ljerka Kondres, Sajma Zajcic, Nikola Janusic