当取心钻具采用双层管时，钻进所用的钻头就需要用普通双管钻头。

Conventional double tube bits should be used as bits for drilling, while coring tool is double tube.

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使用1 / 16“钻头，钻一个孔在上面管中间的横截面。这将使天然气逃脱焊接过程。

Using a 1/16" drill bit, drill a hole in the middle of the cross section tube above. This will allow gas to escape during welding."

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本文介绍了薄壁管专用钻头的结构特点及工作原理，其结构设计新颖，对薄壁管的钻削有实用价值。

In this paper, the structure feature and principle of this special drill has been introduced. Its special design is very useful for drilling thin-wall pipe.

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