THE TRADITIONAL WONGAWILLI METHOD
Panel & Pillar Extraction 0 CommentProblems encountered with the Old Ben system prompted the design of Wongawilli system of Pillar extraction, and the following parameters were set: 1. Provision of a single working place 2. Extraction of coal in stress relieved areas 3. Utilisation of the coal in stress as a support 4. Maximise extraction of […]
Read MoreOLD BEN SYSTEM
Panel & Pillar Extraction 0 CommentWhen the statutory limitations on pillar extraction by mechanical means were lifted in NSW, a number of problems became evident due to the time which had elapsed from the development of the original workings. Many pillars had partially crushed due to the time they had stood unworked or due to […]
Read MoreTHICK SEAM MINING
Traditional Pillar Extraction 0 CommentThe method was designed to limit some of the problemsinherent with the open ended lifting. It reduces the lenght of each lift so the a continuous miner and its crew are exposed to a lesser span of cantilevered roof. It is not so amenable to ad hoc changes to the […]
Read MoreOPEN ENDED LIFTING
Traditional Pillar Extraction 0 CommentIn this method a succession of drives is made down the goaf side or sides of the pillar (picture). Roof support for the drives is by rows of breaking-off propos placed along the goaf sideand with or without cross timber to support the immediate roof of the place. The method […]
Read MoreFIRST WORKINGS
Method 0 CommentFirst 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. The number of development headings […]
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