There is no need to control the rotational position about the axis of the bore, because up to the time when the holes are drilled, it is symmetrical about that axis.
由于直至钻这些小孔时，工件都对称于大孔轴线，所以没必要控制围绕大孔轴线回转的位置。
2
These two methods can be used to strengthen and repair surface for large-scale axis parts and bore of bearing.
这两种方法适合大型轴类零件的表面强化和修复。
3
The inner bore extends along the longitudinal axis at least partially through the gripping member, and opens on at least the first end of the gripping member.