Adopt ceramic nozzle can be the nozzle, that is set to zero height vent end direct contact with the surface is cut, can achieve very good result.

采用陶瓷外喷嘴可以将喷嘴高度设为零，即喷口端面直接接触被切割表面，可以获得很好的效果。

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The bell of the motor nozzle, which was machined from a single piece of steel, is visible at the aft end of the rocket.

钟的发动机喷管，这是加工从单一的一块钢，可见在尾部结束火箭。

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Five, the nozzle height: refers to the nozzle surface and cutting the distance from the end, it constitutes the part of the whole arc long.

喷嘴高度：指喷嘴端面与切割表面的距离，它构成了整个弧长的一部分。

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In December 2010, when two cracks were discovered at the end on the second-stage engine nozzle on the Falcon 9, a cadre of NASA experts urged extensive analysis and testing before attempting to launch.

WSJ: SpaceX Acts Fast for New Launch