The mining sequence in the middle stage of the mine field is either down-and-down. The down-drilling sequence is the first mining method, the lower mining phase, and the mining method from the top to the bottom (or several stages simultaneously, but the upper stage leads the lower stage). The upside is the opposite.
In the production practice, the down mining order is generally adopted. Because the down-type mining has the advantages of small initial investment, short construction time, fast production, and gradual mining, it can further explore the advantages of deep ore bodies to avoid waste.
2 ) Mining sequence of nuggets in the stage
According to the positional relationship of the main development wells (main wells and main flats), the mining order of the nuggets in the stage can be divided into the following three types:
(1) Forward mining: After the transportation of the roadway has been carried out for a certain distance, it starts mining from the nuggets close to the main development wells and advances to the boundary of the well field. The advantage of this mining sequence is that the construction time is short and the production is fast; the disadvantage is that the maintenance cost of the roadway is high.
(2) Retreat mining: After the stage transportation roadway is digging into the minefield boundary, starting from the nugget at the boundary of the minefield, it will be sequentially recovered in the direction of the main development well. The advantages and disadvantages of this mining sequence are basically the opposite of the forward mode.
(3) Mixed mining: that is, the initial mining is carried out in the initial stage. After the transportation of the roadway to the minefield boundary, the retreat type is used. Although the mining sequence utilizes the advantages of the above two mining sequences, the production management is complicated.
In the actual production, the backward mining sequence is generally adopted.
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