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繩索取芯工具是一種不提鉆而從鉆桿內(nèi)撈取巖芯的鉆井工具。整套鉆具包括：鉆具總成、打撈器、鉆桿、絞車、提引器、夾持器及自由鉗等部件。它具有鉆進效率高、巖芯采取率高、鉆頭壽命長、勞動強度小等優(yōu)點。隨著鉆孔的加深，其優(yōu)勢更為明顯。

Wire-line drill tools can lift drill core from drill rods without picking up bit.All the tools include principal of the drill tools,overshot assembly,drill rods,holding dog,circle wrench and etc.Their advantages are higher penetrarion,higher core recovery ratio.Longer bit life and lower labour intensity,and the advantages get more clear with the increasing of hole depth.