SYSTEM AND METHOD FOR SHAPING A DUCT SECTION

Coal and gas outburst monitoring device

Track structure with center rail

Vertical orthogonal top exhausting air duct structure of deeply-buried subway station and construction method therefor

Collaborative erosion-control method of releasing-splitting-supporting based on coal mass pressure relief and roof pre-splitting

Nuclear island base slab of nuclear power plant, manufacturing method therefor, and nuclear island of nuclear power plant

Track structure with hollow center rail usable as ventilation duct

Ventilation system

SYNERGISTIC MINING METHOD FOR UNDERGROUND MINING, SEPARATION AND FILLING FOR A CLOSE DISTANCE COAL SEAM GROUP

Method for radially mining open-pit end slope pressed coal

Ground wellhole dedicated protective pipe for gas extraction of mining-induced area

POLYMER LINER SYSTEM AND METHOD FOR LINING A VERTICAL SHAFT

Hose for providing an emergency fresh air supply to an underground vault after an explosion

Security for grate covering underground air vents

VENTILATION DUCT

Underground ventilation apparatus and method

System and method of pouring concrete around a flexible ventilation duct assembly

VENTILATION DUCTING SYSTEMS & METHODS

Mine ventilation structure and a deck panel for such a structure

Duct with electrically conductive coating

Ventilation ducting arrangement

Reinforced mine ventilation device