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Sofol-ийн хийж байгаа зүйл бол хэрэглэгчдэд хэмнэлттэй, тохиромжтой үйлдвэрлэлийн шугамыг тохируулах, брэндийн үнэ цэнийг бий болгох явдал юм.
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Sofol-ийн хийж байгаа зүйл бол хэрэглэгчдэд хэмнэлттэй, тохиромжтой үйлдвэрлэлийн шугамыг тохируулах, брэндийн үнэ цэнийг бий болгох явдал юм.
Guidelines for hard rock pillar design in South African bord-and-pillar operations are presented in this report as well as a proposed multi-year research project to address the unknowns in terms of pillar design.
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Bord and pillar mining method comprises two phases, i.e., development or 'whole working' and depillaring or 'broken working'. Sometimes both these phases proceed simultaneously.
WhatsApp: +86 18221755073
One among the oldest methods of mining is that the Bord and Pillar. It's a way within which the mined material is extracted across a horizontal plane while leaving "pillars" of untouched material to support the overburden leaving open areas or "rooms" underground.
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This diagram shows the traditional method of bord and pillar mining. Miners extracted coal along roadways or bords, with the coal between the bords acting as pillars holding up the roof. The outer pillars were then mined, leaving the roof to collapse in a controlled way as the miners retreated ...
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It begins by introducing bord and pillar mining and explaining that it involves driving parallel roads separated by coal pillars. It then explains some key aspects of bord and pillar design, including that the optimal pillar size is critical to ensure stability without leaving too much coal behind.
WhatsApp: +86 18221755073
Bord-and-pillar mining has some favourable promises such as improving labour difficulties, lowering operating costs and providing safer working conditions.
WhatsApp: +86 18221755073
The document discusses the bord and pillar method of underground coal mining. It describes how the method involves driving a series of parallel roads separated by blocks of coal (pillars) to develop the mine. After development, the pillars are extracted in the depillaring stage.
WhatsApp: +86 18221755073
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