Double-layer barrel drill for rock-socketed construction of large-diameter rotary excavating pile

The utility model discloses a double-layer barrel drill for rock-socketed construction of a large-diameter rotary excavating pile. The double-layer barrel drill comprises an inner barrel body, an outer barrel body and a rotary excavating drill bit, an annular cavity is formed between the outer surface of the inner barrel and the inner surface of the outer barrel, a plurality of inclined drilling teeth with the same orientation are fixed to the bottoms of the inner barrel and the outer barrel along the circumferential edges, a rotary excavating drill bit is installed in the inner barrel in a nested mode, and the rotary excavating drill bit is directly connected to the end of a drill column of the rotary excavating drilling machine; the lower edge of the inner cylinder is lower than the lower edge of the outer cylinder, and the lower edge of the rotary excavating drill bit is lower than the lower edge of the inner cylinder; and the inner barrel and the outer barrel are fixed on a drill column of the rotary dril