The loosening holes outside the plough cut are also drilled at an Angle which improves the breakage possibility.

在楔形掏槽眼外侧的扩槽眼也要有角度以改善爆破效果。

youdao

The loosening holes outside the plough cut are also drilled at an Angle which improves the breakage possibility.

在楔形掏槽眼外侧的扩槽眼也要有角度以改善爆破效果。

youdao