These provide access to the central bore of the well underneath most of the heavy valves which should have closed off the flow of oil, but for some reason did not.

这些为连接在许多沉重的真空阀下的钻井中心的钻孔提供了条件。这些真空阀本应该阻止石油的外泄，但出于某种原因没有做到这一点。

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In sticky oil production, economy, efficiency, environmental protection for well bore to reduce density is very important.

在稠油开采中，经济、有效、环保的井筒降粘技术是十分重要的。

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Application of insulation tech for well bore breaks off the heat exchange which is economic and efficient, and has gained a satisfied effect in test for dense oil well of Bohai oilfield.

井筒保温管技术的应用，阻止式隔绝了热交换的发生，经济、有效，在渤海稠油井测试中取得了满意的作业效果。

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About 2, 400 barrels of oil had escaped through the well bore, seeped up into the rock, then escaped through fissures in the seafloor.

FORBES: Chevron's Expensive Problems

Oil and gas companies use traditional horizontal drilling techniques to bore into the land were gas is trapped.

FORBES: China Closer To Joining Shale Gas Fracking Craze

These provide access to the central bore of the well underneath most of the heavy valves which should have closed off the flow of oil, but for some reason did not.

ECONOMIST: The Gulf oil spill