Patents Assigned to Njal Underhaug
  • Patent number: 6234719
    Abstract: A method in or relating to piling of e.g. tubular bases which are placed and, possibly, casted within a hole drilled out in earth mass in ground or the like is described. One uses a generally known drilling rig, in which a bit is assigned a drilling hammer, and drills a hold having a depth approximately corresponding to the base pipe. If there exists a need for piling, the drill string is swung aside, away from the hole, after having been pulled up, and one or, possibly, a plurality of piles is/are rammed down with a starting point at the bottom level of the bore hole. In order to drive the pile(s) down, the drilling hammer of the drilling rig is used.
    Type: Grant
    Filed: July 2, 1999
    Date of Patent: May 22, 2001
    Assignee: Njal Underhaug
    Inventor: Tom Toralv Roynestad