File:LongwallOld.png
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Summary
| Description |
English: Original caption: "Fig. 24. -- Plan of individual roadway longwall mine." The three-compartment hoisting shaft is in the center of the central pillar, which is not mined in order to avoid subsidance around the hoist. The downdraft ventilation shaft is 100' left of the pillar. Arrows show directions of air flow. Access to the face is through roadways through the gob, protected by packwalls, and with the roof "brushed" to maintain clearance as the roof subsides. |
| Date | |
| Source | Coal Mining Methods in Missouri, School of Mines and Metallurgy Bulletin, Vol. 5, No. 4, University of Missouri, Rolla |
| Author | William Walbridge Weigel |
Licensing
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This media file is in the public domain in the United States. This applies to U.S. works where the copyright has expired, often because its first publication occurred prior to January 1, 1931, and if not then due to lack of notice or renewal. See this page for further explanation.
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| Date/Time | Thumbnail | Dimensions | User | Comment | |
|---|---|---|---|---|---|
| current | 15:15, 2 July 2009 | | 738 × 1,000 (133 KB) | Douglas W. Jones | {{Information |Description={{en|1=Original caption: "Fig. 24. -- Plan of individual roadway longwall mine." The three-compartment hoisting shaft is in the center of the central pillar, which is not mined in order to avoid subsidance around the hoist. T |
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