In general drilling, axes decline and diameter enlarged of the hole are the main problems to affect the precision of machine tooling.

麻花钻普通钻削中，孔轴线的偏斜和孔径的扩大是影响其加工精度的主要问题。

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In this paper the relation between the hole diameter and the pile thickness of the jet on the hole bottom for a jet penetrating or drilling process is theoretically examined.

本文在理论上探讨了射流在侵彻或钻孔过程中，孔径和射流在孔底的堆积厚度之间的关系。

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The article describes how DF concept is used in the design of pressure feeders in small-diameter deep-hole drilling process.

介绍如何应用DF 系统原理设计小直径深孔加工中吸压送水器的问题。

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Drilling a 2 or 3 foot hole can be done with normal equipment, while drilling a ten, fifty, or one hundred foot diameter vertical hole would require an entirely new invention.

FORBES: Why Can't We Start Building The World's Deepest Building?

It is currently drilling a 17.5-inch diameter hole -- smaller than the 28 inches required to rescue the miners -- in an effort to realign after veering off course over the weekend.

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