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冲击钻井
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- Can drill further into the water table than dug wells, even drilling past one water table to reach another.与挖井相比，冲击钻井能深入地下水位更深，甚至可以超过一个地下水位而达到另一个。 <br>
| valign="top" | - The equipment can be very heavy and relatively expensive.钻井设备可能很重， 相对而言也较昂贵。<br>
- Especially in harder rock the method is slow (weeks, rather than days).尤其当岩石更为坚硬时，这一钻井方法较慢（需要几周，而不仅是几天） 尤其当岩石更为坚硬时，这一钻井方法较慢（需要几周，而不仅是几天）。 <br>- When temporary casing has to be used, the time taken driving and removing it can significantly increase drilling time.在必须使用临时套管的情况下，花费在的装卸套管的时间会大量增加钻井时间。<br>
- Equipment costs are high and the method is slow (resulting in high cost / drilled meter). <br>
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