Patent ID: 7000714
Filing Date: 2006-02-21
Classification: E02D,E21B

Abstract:
1. A head for injecting a fluid under pressure to break up ground from a borehole, wherein said head has a longitudinal axis and is mounted to a string of rods or tubes having a bottom end, said string including a first feed pipe having a bottom end and disposed coaxially with said string of rods for feeding fluid under pressure, said head comprising: a body having a top end connected to the bottom end of the string of rods or tubes; a bottom wall; a mechanical drilling tooling mounted on said bottom wall and including a second feed pipe; an outer wall connected to said bottom wall; at least one injection nozzle mounted in said outer wall, said at least one injection nozzle having: a duct located inside said outer wall and above said bottom wall, connecting said first feed pipe to the inlet of said at least one injection nozzle, said duct having: a chamber disposed at the bottom wall of said head; at least one feed channel for feeding said mechanical tool with fluid under pressure, said at least one feed channel having a first end end a second end, wherein the first end of said at least one feed channel is connected to the first end of the duct, and wherein the second end of said at least one feed channel is connected to said chamber; and a controllable valve interposed between said chamber and said second feed pipe of said mechanical tool.