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[lawng-wawl, long-] /ˈlɔŋˌwɔl, ˈlɒŋ-/
adjective, Mining.
noting or pertaining to a means of extracting coal or other minerals in an underground mine from a continuous face, the roof before the face being supported at intervals by temporary or movable artificial supports.
Compare room-and-pillar.
the continuous face so worked.
Origin of longwall
1830-40; long1 + wall Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for longwall
  • longwall development is strikingly similar to the development for room-and-pillar mining.
  • Contributions during mining from major longwall dust sources thus increased the potential dust exposure from this source.
  • Eighty-eight percent of our coal is produced using the longwall method of mining.
  • The longwall coordinator and general mine foreman are responsible for longwall moves.
  • The longwall tailgate entries are also being explored.
  • The lease modification areas will allow four additional longwall panels to be mined.
  • One set of guidelines is specific for longwall mining operations.
  • The caved rock behind the advancing longwall face, known as the gob, has a significant effect on methane flow patterns.
  • longwall mining involves driving parallel sets of chain pillars and then removing all of the coal between the chain pillars.

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