Patents by Inventor Rienk M. Nijholt

Rienk M. Nijholt 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).

  • Method of manufacture of pig iron using hollow tube to reseal tap role
    Patent number: 5058864
    Abstract: In the manufacture of pig-iron in a shaft furnace, a taphole is closed with hardened plugging compound during making of the iron and is opened for the tapping of the iron and then resealed. The resealing of the taphole comprises inserting hardenable plugging compound into the taphole and, before hardening thereof, driving a hollow tube into the plugging compound. The hollow tube has an open front end. The tube is pulled out at the next tapping. The use of a tube avoids disturbance of the plugging compound and creates a smoother taphole, leading to improved flow of liquid iron.
    Type: Grant
    Filed: March 6, 1991
    Date of Patent: October 22, 1991
    Assignee: Hoogovens Groep BV
    Inventors: Ronald N. Molenaar, Rienk M. Nijholt