Patent ID: 6189630
Filing Date: 2001-02-20
Classification: E21B

Abstract:
A core barrel having a working end for excavating ground in which substantially vertical foundation piles or secant wall piles are to be constructed, said core barrel comprising:a drive mechanism proximate a top end of said core barrel and adapted to receive a rotating kelly bar or top drive rotary;at least one core barrel wall defining a hollow interior of said core barrel and having a diameter of at least 36 inches;a plurality of hammer drills disposed proximate the perimeter of said core barrel, each of said hammer drills having a working end extending past said core barrel wall sufficiently far to cut a kerf having a diameter greater than said top end of the core barrel;a plurality of air conduits, each of said air conduits connected to one of said plurality of hammer drills for delivering pressurized air thereto.