Patent ID: 6581702
Filing Date: 2003-06-24
Classification: E21B

Abstract:
A three-cone rock bit comprising:a drill hit body comprising a first end to connect with a drill string and a second end delimiting a cutting surface formed by a plurality of rotary cutter cones, said plurality of rotary cutter cones having at least one void defined above the cutter cones; a nozzle located above said cutter cones along a central vertical axis of said bit body; said nozzle further comprising a sidewall and a central passageway, said central passageway defining an inlet aperture at a top of the nozzle, and a main exit aperture at a bottom of the nozzle; said central passageway of said nozzle defining a descending tapering shape; said bit body further comprising an opening passageway extending through a top portion of said bit body in an axial direction, thereby keeping said drill string in fluid communication with said nozzle; means for attaching said nozzle within the opening passageway of said bit body; said nozzle further comprising a plurality of side passageways extending through the sidewall intermediate the top and bottom of the nozzle, each of said side passageways comprising an exit orifice at an exterior surface of said nozzle; a plurality of inlet orifices; each said inlet orifice leading to a corresponding said side passageway; said plurality of inlet orifices being individually, vertically staggered along said central passageway; each said inlet orifice sized to restrict passage of particles too large to completely pass through said corresponding side passageway; and said main exit aperture having a greater diameter then each said inlet orifice.