guide hole meaning in English

超前炮眼
导孔
导向孔
导向钻孔
导销孔

Dual probe guiding hole drilling process for accurate probe contact
凸形孔制程，提高探针准确度。
The wedge disc of the valve with flow guide hole is always fitted with the sealing face whether in full open or full close status to have the sealing face protected without being directly eroded by the medium so as to extend the duration
带导流孔阀门的闸板，无论是全开或是全关始终与密封面吻合，密封面得到保护不受介质直接冲刷，从而延长使用寿命。