| 摘要 |
Coring apparatus for obtaining core samples which may comprise: an outer barrel assembly, the lower end of which is adapted for connection to a core bit, the upper end of which is adapted for connection to a drill string; an inner barrel assembly concentrically disposed within the outer barrel assembly and having first and second axially spaced and fluid communicating chambers therein; and valve means carried by the inner barrel assembly and movable from an open position, in which a core sample may be received by the first chamber, to a closed position, sealingly enclosing the core sample within the first chamber. A method of obtaining core samples with the coring apparatus may comprise the steps of: lowering the coring apparatus and a core bit into a well bore on a drill string; rotating the drill string so the core bit cuts away an annular area at the bottom of the well bore, leaving a substantially cylindrical core extending upwardly into the inner barrel assembly; breaking the core near the base thereof to provide a core sample of desired length; continuing to rotate the drill string until the broken core sample is totally within the first chamber; lifting the drill string to clear core remaining in the well bore; actuating the valve assembly to sealingly enclose the core sample within the inner barrel assembly; and raising the coring apparatus to the surface of the well while allowing at least some of the fluid contained in the core sample to expand into the second chamber.
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