The Vertical Deep Hole Spherical Pouch Mining Stage Method (VCR method) is a high-efficiency, safe and economical empty-field mining method characterized by large-diameter vertical deep-hole spherical packet falling ore. It comprehensively applies the achievements of new technologies and new processes such as large-diameter deep hole rock drilling equipment, spherical drug blasting theory and large-scale trackless mining equipment. 
The method is to excavate the rock drilling chamber (roadway) for rock drilling in the upper part of the ore block. The large diameter down-the-hole drilling rig (or roller rig ) is used to drill the deep hole to the deep hole until the lower part of the ore block is pulled down. Horizontal, and then from the lower part of the blasthole by the method of blasting with a spherical drug-packing funnel, layering from the bottom to the top until the upper level of the ore block. The ore that has collapsed is transported from the lower ore roadway.
Official large diameter and deep hole mining technology in underground mining first appeared in Canada's Copper Cliff North Mine in early 1973 for stage room mining method in Mine. At the end of 1973, in a column of 48m long, 6m wide and 19~25m high in the Levac copper mine of the International Nickel Corporation, a 165mm diameter vertical vertical blasthole and spherical blasting was used to successfully carry out the blasting. The first VCR method production scale test. Figure 1.
Figure 1 VCR method for the first time that Levac copper mine is used for returning to the mining column
1-filling body; 2-rock drilling chamber; 3-transporting roadway; 4-mining and penetrating roadway;
5-lower blasthole; 6-gun hole; 1~4-layered ore sequence
Subsequently, mines in countries such as the United States, Australia, Spain and Sweden were successively applied to production.
China began to apply the VCR method in 1980. Successfully tested in 1983 and between stope filling method Fankou lead zinc ore column. Since then, one after another to promote law VCR test different scenarios in Sichuan two gold mines, Jinchangyu Gold, giant pit copper mine tin ore body number 91, Tongling copper, copper and other Phoenix Mountains.
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