The sequence of excavation for the shaft of diversion system at Pushihe storage power station is to excavate the pioneer well used by back well boring machine, then by hand air drill to expand it.

蒲石河抽水蓄能电站引水系统中的竖井开挖，拟采用反井钻机进行导井开挖，人工手风钻钻孔扩挖的方式施工。

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Suitable for broaching or tapping in the cabined place. The air drill is light, good rigidity an can be used for drilling in reverse, aiguilles of which has short distance form the border to center.

用于狭窄部位钻孔，扩孔攻丝等作业，具有重量轻，刚性好，钻削头边心距小等特点，且可反转。

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You need plenty of air so that you can take your time and experience what this drill has to offer.

前尽可能你需要充足的空气，这样你就可以把你的时间和经历这个钻子所提供的。

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To determine whether a deposit has enough of a mineral to merit mining, companies use air-based geological mapping and drill for core samples.

WSJ: Exhausting the Earth's Resources? Not So Fast

These dry, 15-to-20-second statements are as fun to listen to as the dentist's drill, and make the air only under the strictest of rules: There can be no mention of products, and no appeal to buy anything.

FORBES: Public Radio Goes Begging

They also noted the deployment of Russia's most advanced S-400 air defence system in Belarus and a parallel drill conducted by the Strategic Rocket Forces, the guardians of the Kremlin's nuclear arsenal.

ECONOMIST: NATO and Russia