Borehole seals are connected directly with the injection line and inserted into the borehole down to the required depth. In the front area the borehole seal is equipped with a bursting disc blocking the flow of the injection material. Thus, at first, the
material runs through the lateral outlets, lifts the tube valve, and fills the inflation hose until the inside diameter of the borehole is reached. When the required pressure has been built up, the bursting disc cracks and unblocks the passage. Due to the pressure drop the tube valve returns to its initial position on the lateral outlets to block the reflux of the injection material out of the inflation hose. After the injection work has been finished, the valve (sealing lip valve, tube valve) at the tip of the borehole seal obstructs the passage in backward direction and seals the borehole. Borehole seals can be fixed safely even while water, gases, etc. are escaping. Borehole seals are used in the field of mining and tunnelling, for stabilisation, water drillings, exploration drillings, etc.
