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In underground mining operations, conditions such as blasting and gas outbursts may generate intense shock waves, posing fatal threats to tunnel structures, equipment, and personnel. The Shock Resistant Valve, a safety device designed for this specific purpose, employs a dual mechanism of "directional pressure relief" and "instant closure."
link:https://www.rlycn.com/mining-ventilation-system/mine-doors/shock-wave-resistant-valve.html
Shock Wave Resistant Valve