摘要 |
A device for closing off a mine gallery, especially for use to prevent spreading of underground explosions, in which a bag of flexible substantially airtight material is first inflated with a gas under pressure, for instance air, until the inflated bag engages with its peripheral surface the inner face of the mine gallery, whereafter a flowable material is pumped into the interior of the bag, displacing the gas under pressure, which is permitted to escape through at least one overpressure valve provided in an uppermost portion of the inflatable bag. The material to be pumped into the interior of the bag is of a nature which quickly hardens after being pumped into the bag to thus provide a solid barrier extending across the mine gallery.
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