Reciprocatory Plunger Patents (Class 105/233)
  • Patent number: 4907916
    Abstract: A tool for inserting pipe piers, the method of forming such piers and a pressure grouted pier are disclosed. The tool utilizes a complementary double clamping system which allows faster pipe insertion and minimizes loading and unloading of the foundation as the pipe is driven. The tool further allows for pressurized grout to be forced through the pipe and into a volume along at least a portion of the length of the pipe to form a pier having improved stability in unstable soil.
    Type: Grant
    Filed: March 15, 1989
    Date of Patent: March 13, 1990
    Inventor: Philip L. Hartman