Coal mining machine cuts swath wider than itself and cuts entry passages into coal seam in one pass.
Miner for Cutting Entry Passages in Coal Seams
NASA Tech Briefs ; 8 , 1
1984-04-01
Miscellaneous
No indication
English
Bidirectional Continuous Coal Miner
NTRS | 1984
|Engineering Index Backfile | 1964
Tractor tread shuttle cars used in steeply pitching coal seams
Engineering Index Backfile | 1953
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