| 摘要 |
PROBLEM TO BE SOLVED: To provide an improved double-core tube sampler which enables efficient coring. SOLUTION: In this double-core tube sampler, a drain hole (12c) for discharging water, supplied in excavation, to the outside is provided in a side wall slightly above the tip of a bit (12); the tip of the bit has such a stepped shape that an inner peripheral part (12a) is elongated in the direction of the tip with respect to an outer peripheral part (12b); and the inner peripheral part is formed of a dry diamond. Preferably, a reamer (12d) serving as a diameter-enlarged part is provided in a part below the weep hole of the side wall of the bit. COPYRIGHT: (C)2005,JPO&NCIPI
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