Why is it taking so long to shut off the flow of oil? What methods have been tried to stop the oil flow at its source?

为什么需要花这么多的时间才能止住漏油？在这个过程中，我们都尝试了那些方法？

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A built-in automatic oiling system provides continuous oil flow to the cutting heads, for improved performance and blade life.

内置的自动加油系统提供持续的机油流向切割头，提高了刀片性能并延长了机器的使用寿命。

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Gaps in oil flow indicate unused capacity.

油流中的间隙表示未使用容量。

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Federal officials say stopping the oil flow could take weeks or even months.

VOA: standard.2010.05.02

But,once the fire is out, the well still needs to be covered,or capped, to stop the flow of oil.

VOA: special.2009.03.22

Some of the oil will flow out of the bag and can be collected.

VOA: special.2009.09.29

One key to Mix finding a solution to stop the oil flow was to calculate how much oil was gushing into the Gulf.

FORBES: Indictment of Fmr BP Exec Could Exonerate Another Fmr BP Engineer - Kurt Mix

British oil company BP, one of the firms operating the rig, has not been able to activate a device known as a blow-out preventer, designed to stop oil flow in an emergency.

BBC: Growing concerns over Gulf of Mexico oil leak

The oil sector could also get hit hard, with Iran potentially mining the Persian Gulf and attempting to close the Straits of Hormuz, putting a stranglehold on oil flow, Shepperd says.

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