Our non-ferrous metals, ferrous metals, chemical, nuclear industry, building materials, mining, extensive mining stope mining method in the open air room conditions pillar of the stay. In 1983, 25 non-ferrous metal mines were surveyed, and 23 of them were returned to the mining column in whole or in part. The advantages are simple process, high recovery strength and efficiency, and low cost. However, it is not suitable for mining when the ore value and grade are high or when it is necessary to protect the surface.
According to the stability of the ore rock, the dip angle of the ore body, and whether the upper empty area is collapsed, the pillars of the open-pit mine can be recovered by the empty field method or the caving method respectively.
In addition to the stability of the ore surrounding rock, the empty field method back to the mining column is generally used for the following situations: (1) horizontal or gently inclined thin to medium-thick ore bodies; (2) small-scale blind ore bodies; (3) steeply inclined ore The surrounding rock is stable at the first or subsequent stage of the body, and the empty area does not collapse naturally during the equivalent period. In the first case, only a part of the pillars are selectively recovered; in the second and third cases, the pillars can be all recovered. To ensure safety, a certain thickness of the ore cushion can be left or other measures can be taken. The empty area after returning to the mining column can be treated by isolation, caving or other methods depending on the specific situation.
Under other conditions, the caving method is used to return to the mining column. At the same time as the pillar collapses, it collapses the surrounding rock or transfers the upper part of the overburden rock, and the ore is discharged under the overburden.
Overview of Steel Bar Cutting Machine
The steel Bar Cutting Machine is a kind of tool used to shear steel bars.
There are automatic steel cutting machine and semi-automatic steel cutting machine.
It is one of the necessary equipment for steel rebar processing, and it is mainly used to cut off the length of rebar in buildings, Bridges, tunnels, power stations and large water conservancy projects.
Compared with other cutting equipment, the steel bar cutting machine has the characteristics of light weight, less energy consumption, reliable work and high efficiency. Therefore, it has been widely used in mechanical processing and small rolling mills in recent years, playing an important role in various fields of national economic construction.
Steel Bar Cutter
Steel Bar Cutter,Steel Cutter,Hydraulic Rod Cutter,Steel Bar Cutting Machine
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