單動(dòng)雙層巖芯管鉆具結(jié)構(gòu)簡(jiǎn)單,、操作方便,、同軸度好,、適用壽命長(zhǎng),,能有效地提高巖、礦芯的完整度,。
The swivel-tube barrel can effectively increase core recovery rato.suitable for drilling in formations in which oblique hole comes easy.It is effective to assure hole quality.