A ladderway system for underground raises
A p-aromatic polyamide vent duct and its application, and...
A tube of fabric reinforced pvc
A tunnel cover for a tunnel for controlled ventilation of gas
Adjustable stairway for use with an overcast in a mine
Air stopping in underground mines
Airflow regulator
An advancing tailpiece
Anchored mine ventilation structure
Apparatus for assembling a liner
Apparatus for preventing the spontaneous combustion of...
Arrangement for passage control of mine vehicles
Articulated haulage vehicle
Articulated haulage vehicle
Articulated railway vehicle
Artificial underground cavern for storing natural gas in gas...