Inflatable packing sealing borehole - has piston in hose-supporting tube shutting off filling material and with crown bursting to deliver into hole

摘要

The hose (2), supported on a tube (1), is inflated by the filling material and sealed, opening automatically on exceeding a set pressure to fill the borehole. A piston (7) sliding int he tube shuts off the interior of the inflated hose from the supply of material when a predetermined pressure is exceeded. Its crown bursts to form an outlet via which filling of the borehole takes place. The piston can be a press-fit in the tube, and the pressure required to burst its crown can be greater than that necessary to slide it in the tube. Its crown (10) can be connected via a fracture point to its skirt. ADVANTAGE - Simplicity, reliability, and usable with wide range of hose material.