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Nov 21, 2019· Bord and pillar mining method comprises two phases DEVELOPMENT and DEPILLARING. Sometimes both these phases proceeds simultaneously. In development, pillars are formed by driving a network of galleries, of which one set is generally parallel to the dip and the other set is parallel to the strike cutting the former at right angles.
Feb 27, 2016· Bord and Pillar method of mining is one of the oldest methods. 3. INTRODUCTION In India, about 98% of underground output of coal is obtained by Bord and Pillar method and barely about 2% by longwall methods. The other countries where Bord and Pillar method predominates are Australia, The USA and South Africa.
Bord and pillar mining Next. This diagram shows the traditional method of bord and pillar mining. Miners first extracted coal along roadways or bords, while the coal in between the bords acted as pillars holding up the roof. Then the outer pillars were mined, leaving the roof to collapse in a controlled way as miners retreated to the exit.
Mar 01, 2012· BordandPillar is a system for underground mining (mainly for coal, iron mining) in which a horizontal plane some "pillars" of mined materials are left to support the overburden while mined materials are extracted leaving some open areas around the pillars which are known as "rooms".
May 06, 2011· Cascading Pillar Failure (CPF) CPF is a potential problem faced by all Bordandpillar mining operations. CPF occurs when one pillar fails suddenly, which then overstresses the neighboring pillars, causing them to fail in very rapid succession. Within seconds, very large mining areas can collapse while giving little or no warning. ...
Southern African underground Platinum and Chrome Mines exploit the tabular platinumand chromebearing orebodies using either conventional mining methods making use of jackhammers and air legs, mechanized bord/room and pillar mining layouts or a
Mining Mining Ventilation and lighting: Ventilation is an important consideration in underground mining. In addition to the obvious requirement of providing fresh air for those working underground, there are other demands. For example, dieselpowered equipment is important in many mining systems, and fresh air is required both for combustion and to dilute exhaust contaminants.
The term bordandpillar is not used to any great extent in American mining literature, but has a place in English literature. Various names have been applied to this method, such as checkerboard system, Brown panel system, following up the whole with the broken, Lancashire bordandpillar system, modified roomandpillar working, narrow ...
May 31, 2017· Bordandpillar extractionnbsp;is the older of the methods, andnbsp; The wordnbsp;"bord" is not a misspelling ofnbsp;"board", but a mining term for an underground space or .
Room and pillar. Room and pillar is also known as bord and pillar is a mining system in which the mined material is taken out across a horizontal plane while leaving "pillars" of unscathed material to support the overstrain leaving open regions or "rooms" underground.
Conventional bord and pillar mining in thick seams is associated with very low percentage of extraction [around 30% in a panel] even under favourable conditions. Extensive development of pillars carried out earlier in thick seams had also resulted in large reserves of good quality coal locked up in developed bord and pillar workings [over 2,500
Our cutting tools for bord and pillar mining fit either continuous miners or roadheader machines. They feature a hardened steel body/shank fitted with a wear and impact resistant tungsten carbide tip. Depending on the application, we also...
Cat will no longer build tracked drills, bord and pillar mining machinery. August 19, 2016 News Ben Creagh Cole Latimer. Latest News. Follow the leaders: This week''s appointments ;
Longwall Mining (41) Overview (6) Equipment (17) Shearer (8) Powered Supports (3) Ventilation (3) Change Out (7) Ground Control (8) Bord Pillar (15) Method (7) Traditional Pillar Extraction (2) Panel Pillar Extraction (2) Modern Pillar Extraction (2) Equipment (5) Ground Control (1) Ventilation (2) Rock Bolting (20) Overview (2) Types of ...
CW: The primary benefit of bord and pillar mining is that for an equivalent production the capital cost of a bord and pillar operation would be 45% to 65% of that of a longwall mine. The operating costs may be 30% to 60% more than a longwall, but the risks are significantly less and production variances are very low compared to longwall.
Large roomandpillar stone mining fundamentals The value per ton of ore for large roomandpillar stone mines is typically low, therefore productivity must be high. Typical face areas are m wide x m high (40 ft wide by 25 ft high) with m (14 ft) pulled with each blast (Figure 1). This equates to over 1,000 tons of stone per
Underground Mining. Throughout the years, Moolmans has built extensive experience in coal, platinum, gold, copper and manganese mining, encompassing various mining methods, such as bord and pillar.
General, a pillar greater in size than 18 m x 18 Tm is split up into two stooks. In a large pillar of 30 m x 30 m size between centres, one split m wide in the middle of the pillar along the strike and another split of similar width in the middle of the pillar along the dip, are driven so that the pillar .
Bord and Pillar method of mining. Bord and Pillar method of mining is one of the oldest methods of mining. The success of Bord and Pillar mining is selecting the optimum pillar size. If the pillars are too large, then the extraction ratio decrease leading to less production and profitability and if .
Room and pillar is an underground mining method that has applications to a wide variety of hardrock deposits worldwide. It is commonly classified as an openstoping method, meaning that development involves mining out underground cavities while leaving the .
Bordandpillar definition is of or relating to a system of coal mining in which tunnels are driven in a checkerboard pattern having massive square pillars between them .
Basic parameters of bord and pillar mining system 1. Gallery (bord) 2. Pillar. 3. Junction. Calculation of percentage of extraction during development If coal from the full seam thickness is extracted, the percentage of extraction during development is nearly 20% in deep mines and 35% in shallow mines.
May 08, 2013· Bord and Pillar Method, Mine Ventilation, by OcS () OcSTeam. ... Block Caving Mining Method Duration: 3:17.
Room (Bord)andPillar Layout. ... In room pillar mining, high safety levels in design is important, and to achieve this, understanding the behaviour of the pillars is essential. It is ...
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