Roller cone bit

Abstract

A roller cone bit is described. The roller cone bit includes a body having concave sides. Legs are attached or integral to the body. Roller cones are rotatably engaged to the legs. The concave sides are positioned adjacent the legs. A nozzle is positioned in an approximately central portion of the body.

What is claimed is: 
     
         1 . A roller cone bit, comprising:
 a body having concave sides; and,   a nozzle to spray a drilling fluid, the nozzle comprising an extending portion and an opening, wherein the nozzle is positioned in an approximately central portion of the body.   
     
     
         2 . The roller cone bit according to  claim 1 , wherein legs are integrally attached to the body, and roller cones are rotatably engaged to the legs. 
     
     
         3 . The roller cone bit according to  claim 2 , wherein the concave sides are positioned adjacent to the legs to provide flushing of drill cuttings from a borehole. 
     
     
         4 . The roller cone bit according to  claim 1 , wherein the opening of the nozzle is positioned a distance from a surface of the body. 
     
     
         5 . The roller cone bit according to  claim 2 , wherein the legs and the concave sides are alternatingly arranged about a perimeter of the roller cone bit. 
     
     
         6 . The roller cone bit according to  claim 2 , wherein one of the concave sides is positioned between a pair of the legs. 
     
     
         7 . The roller cone bit according to  claim 2 , wherein the nozzle extends to a point approximately clearing a center cutter of the roller cone bit. 
     
     
         8 . The roller cone bit according to  claim 4 , wherein the extending portion of the nozzle extends from a surface of the central portion of the body, and the opening is positioned away from the surface of the central portion of the body. 
     
     
         9 . The roller cone bit according to  claim 1 , wherein the concave sides extend from an upper portion of the body to a lower portion of the body. 
     
     
         10 . The roller cone bit according to  claim 1 , wherein a length of the concave sides is generally parallel to an axis of rotation of the roller cone bit. 
     
     
         11 . The roller cone bit according to  claim 1 , wherein the bit comprises a first nozzle with a first opening having a first diameter, wherein the bit comprises a second nozzle with a second opening having a second diameter, wherein the second diameter is larger than the first diameter, the second nozzle provides a greater volume of drilling fluid, and the first nozzle provides the drilling fluid at a greater pressure. 
     
     
         12 . The roller cone bit according to  claim 1 , wherein the nozzle is removably engaged to the body. 
     
     
         13 . The roller cone bit according to  claim 1 , wherein the nozzle is in fluidic communication with an interior of the body, and a drilling fluid is forced through the interior of the body and into the nozzle. 
     
     
         14 . The roller cone bit according to  claim 1 , wherein the nozzle passes through a center portion surface of the body, a lower opening of the nozzle is in fluidic communication with an interior of the body, and a drilling fluid is forced through the interior of body and into the lower opening, and the drilling fluid is forced through the extending portion of the nozzle and is discharged at the nozzle opening. 
     
     
         15 . A roller cone bit, comprising:
 a body having concave sides, an upper portion, and a lower portion;   legs are integrally attached to the body, and roller cones are rotatably engaged to the legs;   the concave sides are positioned around an exterior of the body, the concave sides extend from the upper portion of the body to the lower portion of the body, and the concave sides form gaps in the exterior of the body to provide passage of drill cuttings past the body; and,   at least one of the concave sides is positioned between a pair of the legs.   
     
     
         16 . A method of drilling into a rock or earth formation, comprising:
 providing a roller cone bit, comprising: a body having concave sides; legs integrally attached to the body; roller cones rotatably engaged to the legs; the concave sides positioned adjacent the legs; and, a nozzle, comprising an extending portion and an opening; wherein the nozzle is positioned in an approximately central portion of the body; wherein the opening is positioned a distance from a surface of the body;   connecting the roller cone bit to a drill string;   rotating the roller cone bit;   directing fluid to the nozzle; and,   flushing drill cuttings with the fluid past the concave sides.   
     
     
         17 . The method according to  claim 16 , further comprising directing drill cuttings away from the roller cones. 
     
     
         18 . The method according to  claim 16 , further comprising making a pilot hole in the rock or earth formation with the drilling fluid from the nozzle. 
     
     
         19 . The method according to  claim 16 , further comprising adjusting an opening size of the nozzle to modulate pressure and volume of the drilling fluid. 
     
     
         20 . A roller cone bit, comprising:
 a body having concave sides;   legs integrally attached to the body;   roller cones rotatably engaged to the legs;   the concave sides positioned adjacent the legs to provide flushing of drill cuttings from a borehole; and,   a nozzle to spray a drilling fluid, comprising an extending portion and an opening;   wherein the nozzle is positioned in an approximately central portion of the body;   and, wherein the opening is positioned a distance from a surface of the body.   
     
     
         21 . A roller cone bit to drill into earth or rock, comprising:
 a body, the body including an upper portion and a lower portion, the upper portion including a threaded connection portion to connect with a drill string to rotate the roller cone bit;   three legs engaged to a perimeter of the body, each of the legs having an end at the lower portion of the body;   a roller cone rotatably engaged to the ends of each of the legs via a bearing system, wherein each of roller cones includes an inner cutter, a center cutter, and an outer cutter;   the body having three concave sides extending from the upper portion to the lower portion, the concave sides positioned between the legs, the concave sides forming gaps to flush drill cuttings; and,   a nozzle extending from the lower portion of the body to spray a drilling fluid; the nozzle comprising an extending portion and an opening; wherein the nozzle is positioned in an approximately central portion of the lower portion of the body; wherein the nozzle extends to a point approximately clearing the center cutter of the roller cone bit; and, wherein the nozzle is in fluidic communication with a fluid line or an interior of the body.