procedure and device to win a bodenschatzes from a deposit

摘要

An improved method and equipment of removing a minable product, such as coal, from an underground seam of minable product, such as a coal seam, includes the steps of drilling a vertical hole from the earth's surface through the seam of minable product, installing in the recovery hole an improved recoverable down hole tool, having a vertical auger and a hollow shaft extending from the earth's surface to the auger in the down hole tool, water pumped down the hollow shaft exiting through nozzles mounted from below the auger segments in the down hole tool and spaced vertically along the length of the hollow shaft to the earth's surface through the seam of minable product, the injection holes being drilled in a pattern extending from the recovery hole inserting and sequentially igniting explosives in the injection holes, injecting water sequentially in the injection holes and removing the fractured minable product by operating the down hole tool and water nozzles in the recovery hole and raising said minable product to the earth surface.