How is the cavity formed during the mining process of the mining and mining method generally handled?

The use of the mining and mining method generally solves the cavity in the following four ways:
1 The ore is placed on both sides of the arched hollow to destroy the arch of the arched hollow, so that the suspended ore falls;
2 bury a large drug pack above the cavity, and use the explosive force to shake off the suspended ore;
3 use mine rocket blasting to eliminate voids;
4 Wash with high pressure water to eliminate the void.

Commercial Aroma Diffuser

Commercial Scent Diffuser,Commercial Oil Diffuser,Commercial Scent Diffuser Machine,Commercial Air Diffuser

Guangzhou Chiyang Scent Technology Co., Ltd. , https://www.gzdiffuserscent.com