There are two kinds of gun drills, namely, the center-cut gun drill used for drilling blind holes and the trepanning drill.

深孔钻有两种类型，即用于钻盲孔的中心切削深孔钻和套孔钻。

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Suitable for broaching or tapping in the cabined place. The air drill is light, good rigidity an can be used for drilling in reverse, aiguilles of which has short distance form the border to center.

用于狭窄部位钻孔，扩孔攻丝等作业，具有重量轻，刚性好，钻削头边心距小等特点，且可反转。

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