Patents by Inventor John R. Herold

John R. Herold 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).

  • Retrieval tool for back pressure valve and tree test plug
    Patent number: 5782297
    Abstract: A retrieval tool for retrieving a back pressure valve and tree test plug (generally, a check valve) has a spear formed as a solid ring at the bottom with free fingers extending upward. The fingers are resilient and have protrusions adapted to engage a retrieval groove in the check valve. A wedge ring is provided on the tool body to positively lock the fingers in radially outward engagement with the retrieval groove. The wedge ring is fixed to the body by a shear pin so that upon a predetermined axial force the pin shears and releases the wedge ring allowing withdrawal of the tool assembly, if the check valve is stuck in a tubing hanger or coupling.
    Type: Grant
    Filed: August 19, 1996
    Date of Patent: July 21, 1998
    Assignee: FMC Corporation
    Inventors: Martin L. Samuels, Bashir M. Koleilat, David E. Cain, John R. Herold, Neil C. Crawford, Henry Wong
  • Wellhead retrieval tool assembly
    Patent number: 5474124
    Abstract: A wellhead retrieval tool assembly for retrieving a check valve has a spear formed as a solid ring at the bottom with free fingers extending upward. The fingers are resilient and have protrusions adapted to engage a retrieval groove in the check valve. A wedge ring is provided on the tool body to positively lock the fingers in radially outward engagement with the retrieval groove. The wedge ring is fixed to the body by a shear pin so that upon a predetermined axial force the pin shears and releases the wedge allowing withdrawal of the tool assembly.
    Type: Grant
    Filed: August 26, 1994
    Date of Patent: December 12, 1995
    Inventors: Martin L. Samuels, Bashir M. Koleilat, David E. Cain, John R. Herold, Neil C. Crawford