Patents Represented by Attorney Marchella D. Watkins

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  • High pressure conversion for circulating/safety valve
    Patent number: 5411097
    Abstract: A well testing tool for use in high pressure wells where it is desired to pressure test the equipment includes a mandrel that is ported to the interior of the test string. The ported mandrel allows pressure to equalize between the interior of the string and an annular chamber formed between the mandrel and the tool housing, and thereby eliminates the tendency of the mandrel to deform into the chamber.
    Type: Grant
    Filed: May 13, 1994
    Date of Patent: May 2, 1995
    Assignee: Halliburton Company
    Inventors: Kevin R. Manke, Paul Ringgenberg