Patent ID: 6896597
Filing Date: 2005-05-24
Classification: B24C

Abstract:
1. A blasting apparatus comprising: a pressure vessel adapted to contain a particulate blasting medium and a liquid and being comprised of an inlet and a bottom outlet; a conduit along which an entraining pressurized gas can be fed from a pressurizing gas source and with which the interior of the vessel communicates via an opening in the conduit connected to the outlet, the flow of pressurized fluid through the conduit entraining the contents of the vessel for dispersal into the fluid flow for blasting through a delivery line connected to the conduit; a pressurizing means to pump liquid from a liquid source into the vessel behind its contents in terms of its contents' outflow from the vessel through the bottom outlet; and valve means to control the flow of pressurized gas along the conduit; wherein a venturi is located in the conduit immediately upstream of the opening connected to the bottom outlet of the vessel so that the velocity of the pressurized gas is increased as it passes over the opening thereby to increase the quantity of particulate blasting medium entrained by the gas.