Cavitation nozzle plate adapter for rock bits

Claim 1

In a rock bit of the type that utilizes drilling mud directed through a drillstring and through said rock bit, said rock bit comprising: a bit body having a first pin end and a second cutting end, said bit body further forming a chamber therein, said chamber being in direct communication with said drilling mud in said drillstring, one or more non-cavitating nozzles in said bit body in communication with said chamber to direct said drilling mud in a borehole bottom, and one or more separate flow cavitation nozzle restriction means adapted to be positioned adjacent said one or more non-cavitating nozzles, said one or more flow cavitation restriction means comprises a substantially circular flow cavitation disc positioned adjacent said separate non-cavitating nozzle body, said disc forming a central nozzle orifice thereby, a flow cavitating restriction means is positioned within said nozzle orifice, said flow cavitation restriction means being attached to said disc, to cause said drilling mud to exit said nozzle openings in a turbulent flow and to cavitate as said drilling mud passes through said one or more separate nozzle flow restriction means.