The initiation time difference between the cut hole and the back auxiliary hole is controlled within the range of 25 ~ 50ms. After the auxiliary eye explodes, the peripheral eye should be detonated by the same detonator at the same time, and the time difference between the auxiliary eye and the auxiliary eye should be controlled within 75 ~100 ms.
Cut, also known as cut eye, is used for tunnel excavation. The eye hole is arranged at the lower position in the center of the tunnel face (depending on the design). First, blasting is carried out in the hole to throw out the central rock and increase the free surface for the surrounding rock to achieve the best blasting effect. First of all, some rocks on the working face are broken, which makes the working face form a second free face, which creates favorable conditions for the blasting of other blast holes. Cutting quality plays a decisive role in improving rock breaking efficiency and circulating footage. Therefore, it is necessary to choose a reasonable cutting method and charge to make the rock completely broken and form an ideal cavity. There are two kinds of cutting methods: oblique cutting and direct cutting.