| 摘要 |
The present invention regards a method for performing core sampling during drilling of wells, comprising the steps of providing a dual bore drill pipe with drill bit in the end in the well bore, providing means to introduce a drill liquid into an annular space of the drill pipe and return it together with drill cuttings to the surface through centrally arranged return line in the dual bore drill pipe, removing larger cuttings at outlet of return pipe, and perform core testing on these cuttings, knowing where the cuttings come from in the well. The invention also regards a device for performing the invention. |
