Bord-and-pillar Definition & Meaning
ResultThe meaning of BORD-AND-PILLAR 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 which are gradually cut away as the work proceeds.
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Conventional room-and-pillar mining | Britannica
ResultIn coal mining: Room-and-pillar mining. …two main room-and-pillar systems, the conventional and the continuous. In the conventional system, the unit operations of undercutting, drilling, blasting, and loading are performed by separate machines and work crews. In a continuous operation, one machine—the continuous miner—rips …
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Pillar Extraction | SpringerLink
ResultPillar extraction, (also referred to as retreat mining; pillar recovery; stooping; pillar robbing; and bord and pillar second workings) is the practice of forming a series of pillars and then partially or totally extracting some or all of the pillars, usually with mining operations retreating out of a panel. There are a …
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Pillar Extraction | SpringerLink
ResultTHE MODERN WONGAWILLI METHOD. Modern Pillar Extraction 0 Comment. The Wongawilli system involves much larger blocks of up to 200 m wide. It consists of a 2 or 3 heading entry headings …
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recovery by opencast pillar mining in the Witbank coalfield
Resultpillar coal remaining from a previous bord-and-pillar operation that reached its end of life in the 1980s. The underground mine was operated using the conventional drill-and-blast, bord-and-pillar mining method. The pillars were left intact when the underground operation was shut down. In 1995, a project to extract the remaining
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BORD & PILLAR METHOD | Mine Portal
ResultBORD & PILLAR METHOD. Bord and Pillar method: Schemes of development; design of bord and pillar working; statutory provisions; selection of equipment for development -mechanised loaders, continuous miners etc.preparatory arrangement for depillaring; statutory provision for depillaring;designing the system of pillar …
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The Extraction of Pillars Using the Wongawilli …
ResultMine Development . The primary method of developing the mine workings of a coal seam is to adopt what is known as the bord and pillar system. This involves driving a group of development …
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9: Illustration of Bord and Pillar Mining Method (Van der …
ResultThe bords currently mined gave a shorter stand-up time which again compromises safety. Pillars need to be redesigned together with the implementation of a new roofbolt system to improve both ...
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Coal mining
ResultOtherwise, the unrecovered pillars may start to fail, endangering the miners and mining equipment. The general procedure is to extract one row of pillars at a time, leaving the mined-out portion, or gob, free to subside. While extraction of all the coal in a pillar is a desirable objective, partial pillar extraction schemes are more …
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8.3.1: Room and Pillar Method | GEOG 000
Result8.3.1: Room and Pillar Method. Room and pillar mining is arguably the most important underground mining method in practice today. The majority of underground production comes from room and …
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THE MODERN WONGAWILLI METHOD – Mining Science …
ResultThe production and productivity of the Wongawilli system is tied up with coal cutting, support setting and coal clearance systems deployed. It is clear from Table 3 that correct combination of equipment and operational practices can lead to higher output and productivity as that shown by United, Cook and South Blackwater …
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Bord and pillar challenging longwall dominance
ResultBord and pillar challenging longwall dominance. A CHANGING economic climate and the higher cost of capital is forcing coal miners to look to bord and pillar mining as the way forward rather than a longwall. Bord and pillar mining operating costs are generally higher than those of a longwall but it may provide …
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Shortwall mining at Matla
ResultThe Matla shortwall produces coal at a cost of between 55% to 60% of the average bord and pillar sections. In determining the optimal face length of 127m for the new shortwall section, Nel said a range of criteria were considered. The cost of capital in South African Rand has made big equipment purchases …
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Bord & Pillar – Mining Science and Technology
ResultThe BLS were originally pioneered in the RSA at Middlebult Colliery by Voest-Alpine commencing in 1984 and later trialled in several Australian collieries commencing in 1987. Their subsequent use in pillar extraction panels has become widespread with some 60 units in operation by 1991. A BLS units is illustrated to […]
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PREVIOUS AND CURRENT MINING METHODS.
Resultproved to be competent and the coal mineable. d.) The floor is generally very competent sandstone. 4.2 Mining method and equipment 4.2.1 General The bord and pillar mining layout will be maintained because of its reliability, flexibility, low capital cost, low working costs and large skills source availability (Woodruff, 1966).
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Bord and pillar mining – Coal and coal mining
ResultThis diagram shows the traditional method of bord and pillar mining. Miners extracted coal along roadways or bords, with the coal between the bords acting …
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FIRST WORKINGS – Mining Science and Technology
ResultMethod 0 Comment. First workings are conducted for two main reasons: To develop the pillars, bords and/or panels to enable their subsequent extraction, and. To develop multiple main entries for access to the coal reserves. These entries are supported in the long term by the pillars consequently formed. …
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Pillar Extraction
ResultPillar extraction, also called depillaring, pillar pulling, pillar robbing, and just "pillaring," is the extraction of ore or coal from the pillars left during development. …
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SHUTTLE CAR – Mining Science and Technology
ResultSHUTTLE CAR. out 150 m. By back spooling of cables from an intermediate cable anchorage point the operational reach can be doubled but this may result in reduced cable life and is …
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Defining a representative overall equipment effectiveness …
ResultThe purpose of this article is to show how a representative overall equipment effectiveness (OEE) measurement can be calculated for an underground coal mining bord and pillar batch process. The calculation method, the typical losses (which include planned and unplanned availability losses, coal quality losses, and …
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CONTINUOUS MINER – Mining Science and Technology
ResultContinuous miners operate a room and pillar mining system. A series of 18 to 20 foot wide rooms are driven in the coalbed with pillars or columns of coal left standing to help support the roof. Roof bolts, typically four to six feet long steel bolts, are inserted into holes bored into the roof to bind the strata together support …
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Bord-and-pillar mining in inclined orebodies
ResultThe dimensions of the 16 West excavations were designed to fit the functional dimensions of machines into. Figure 1—Cross section through bord-and-pillars. the dimensions of the orebody with the least amount of dilution. The average reef width in the 16 West area is 135 cm with an average grade of 4.82 g/t.
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Bord & Pillar – Mining Science and Technology
ResultEquipment. Armoured Face Conveyor; Powered Support; Shearer; Pantechnicon; Coal Plough; Beam Stage Loader; Communication; Ground …
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Overall equipment effectiveness optimisation for a …
Resultan underground Bord and Pillar coal mine that has limited coal reserves and unfavorable geological conditions. The mine consists 10 CM sections, mining both high and low seams with equipment-suits that comprises the Continuous Miner (CM), Shuttle Cars, Feeder Breaker, Conveyor Belts and Roof Bolter.
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BREAKER LINE SUPPORT (BLS) – Mining Science and …
ResultThe BLS were originally pioneered in the RSA at Middlebult Colliery by Voest-Alpine commencing in 1984 and later trialled in several Australian collieries commencing in 1987. Their subsequent use in pillar extraction panels has become widespread with some 60 units in operation by 1991. A BLS units is illustrated to the right.
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An evaluation of the equipment used in South Africa for the bord …
ResultFor the purpose of this study, a thin coal seam was regarded as any seam 1,5 m thick or less to the minimum thickness at which mechanized equipment can operate in bord-and-pillar workings. The equipment being utilized in thin-seam bord-and-pillar layouts includes conventional equipment, load-hauldump cars (scoops), …
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Bord and pillar working with LHD/SDL | PPT
ResultBord and pillar working with LHD/SDL. The document discusses mining methods and equipment used for underground coal mining using the bord and pillar method. It provides specifications for various mining equipment used including Load Haul Dumpers (LHDs), Side Discharge Loaders (SDLs), drilling …
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(PDF) Coal Mining Methods Underground Mining Longwall & Room and Pillar
ResultCoal production from the mines in Illinois contributed about 61.7 million tons in 1990. In mines pillars are left to perform a variety of functions which influence their size and disposition. Room and pillar method of coal mining constitute the major mechanism of coal extraction in most parts of the world.
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DESIGN OF SUPPORT SYSTEM IN BORD AND PILLAR …
ResultThe report focuses on designing a support system for bord and pillar mines. Currently, CMRI-RMR and NGI-Q systems are commonly used in Indian coal mines to estimate rock load and design support. However, calculations using NGI-Q can be time-consuming. The objective of this project is to use formulas involving …
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Chronological development in coal pillar design for bord …
ResultBord and pillar method of mining coal seam involves driving two sets of parallel inseam headings, one set being orthogonal to another, thereby forming square or …
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