This adapter may be threaded or welded onto the casing, and may have a flanged or clamped connection to match the BOP stack or wellhead.

该接头也许是用螺纹与套管连接在一起，或焊接在一起，以及可能还有一个法兰或卡箍连接与防喷器组或井口配接。

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The adapter between the first casing string and either the BOP stack (during drilling) or the wellhead (after completion).

在第一根套管柱和防喷器组(钻井时)或完井后的井口之间的一个接头。

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