Patents Assigned to Donald E. Mosing
  • Well casing grip assurance system
    Patent number: 4676312
    Abstract: A casing grip assurance interlock system connected with the elevator and the spider of a well casing installation apparatus including positioning valves respectively actuated by the elevator and the spider to permit actuating fluid pressure to be admitted to either the elevator or the spider only when the other of the elevator or spider is positioned to firmly grip the well casing.
    Type: Grant
    Filed: December 4, 1986
    Date of Patent: June 30, 1987
    Assignee: Donald E. Mosing
    Inventors: Donald E. Mosing, Charles M. Webre