Abstract: Remote operation wire line core sampling device capable of increasing efficiency of working and maintaining a wall of a hole using a stabilized sea-bottom core drill at a sea-bottom, and adopting a wire line system. The device includes a drill rod held by a chuck of the sea-bottom core drill, a wire line core barrel having, at a tip thereof, a bit for annularly drilling into ground, an inner tube assembly detachably incorporated in the wire line core barrel, and an over-shot assembly having a function for engagement thereof with a spear head part at a top end of an inner tube assembly. The device also includes a water swivel in which water supply ports are formed at upper and lower parts thereof, a modified built-in type over-shot assembly is formed at upper and lower parts thereof, and a modified built-in type over-shot assembly is incorporated therein to reside at an intermediate part thereof.

Abstract: Provided is a downhole percussion drill, which is installed at an end portion of a drillstring and performs drilling by giving impact blows to a drill bit at the bottomhole, which includes a hydraulic hammering mechanism 7 which uses oil having high lubricating ability as a driving medium, a hydraulic pump 8 which pressurizes the oil, and a downhole motor 9 which drives the hydraulic pump 8.