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Jetting is based on water circulation and water pressure. As opposed to sludging, water is pumped down the drill pipe and the ‘slurry’ (water and cuttings) is transported up the borehole between the drill pipe and the borehole wall. A motor pump is used to achieve an adequate water flow. The drill pipe may simply have an open end, or a drill bit can be added. Partial or full rotation of the drill pipe can be used. Thickeners (additives) can be added to the water in order to prevent hole collapse and reduce loss of working water (drill fluid).水力喷射是基于水循环和水压的一种方法。与生成淤泥相反，水被泵至钻管下方，“泥浆”（水与钻屑）被向上输送至钻管和井壁之间的探孔。运用马达泵来获得适当的水流。钻管可能只有一端有开口，或者可以增加一个钻头。可使用部分或完全转动钻管。可在水中加增稠剂（添加剂），防止洞口塌陷并降低钻井用水（钻井液）的流失。
Jetting is practiced in a wide range of varieties. The most simple consists of driving a plastic pipe down with water pressure from a motor pump (no drill bit and no rotation, with the water flow jetting the sand up). The depth is limited (no drill bit and extendable pipes). Other systems make use of extendable plastic or galvanized pipes and a drill bit and are rotated during drilling. With these systems greater depth can be reached.水力喷射法使用的方式多样。最简易的是利用马达泵制造的水压将塑料管压下（不用钻头或转动，利用水流将沙子喷射上来），但深度有限（无钻头或可伸长的管子）。其它方法利用了可伸长的塑料或电镀管，使用钻头，且在钻井中进行旋转。使用这些方法，可以达到更深的深度。
===Suitable conditions适宜条件===
[[Image:Manually rotated jetting.jpg|thumb|right|200px|Manually rotated jetting]]
[[Image:Typical drill bit.jpg|thumb|right|200px|Typical drill bit]]