longwall

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Longwall mining

Wikipedia

From long +‎ wall.

longwall (plural longwalls)

1. (mining, often attributive) A long wall of coal that is mined in a single slice.

   Coordinate term: shortwall

   • 1960, Colliery Guardian Overseas, page 50:

     In addition to its work on longwall faces, the A.B. Fifteen has been adapted for shortwall work either as undercutter or as overcutter, particular care having been taken to give it increased manoauvrability by the provision of special pulleys, and increased mobility by the addition of a tilting underframe.