Patent attributes
A stimulation tool for dislodging material from a perforation formed through a tubular disposed in a wellbore includes a main body formed at least in part from a material that is buoyant in a wellbore fluid, a ballast, a magnet, and a pressure pulse generator. The tool is configured to descend downhole by force of gravity when the ballast is attached and couple, by the magnet, to an interior surface of the tubular upon arrival at a downhole location proximate the perforation. When the tool is coupled by the magnet to the interior of the tubular, the tool transmits pressure pulses from the pressure pulse generator into the perforation, thereby dislodging material from the perforation. The tool de-couples from the interior surface and releases the ballast, thereby permitting the tool to ascend uphole, driven at least partially by a buoyant force exerted by the wellbore fluids.