Reverse nozzle drill bit

Abstract

A drill bit design that employs reverse flow nozzles through which a portion of the drilling fluid is diverted. This reverse or upward flow of drilling fluid creates a condition by which the extraction of drilling sludge (combination of drilling fluid and drilling cuttings) in the cutting area of the drill bit is more efficient and has a greater amount of flow than designs of prior art. This increased flow has the effect of more efficiently removing damaging cuttings away from the drill cutters, lubricating the drill cutters more efficiently, and cooling the drill cutters more efficiently. The end result is increased drilling uptime, increased drilling speed, and less frequent drill bit catastrophic failures.

1 . A drill bit for drilling subterranean formations comprising:
 a. a drill bit body extending between a drill bit cutting face and a coupling, the drill bit body having an inner cavity and an outer surface, the inner cavity adapted to receive drilling fluid;   b. a downward passage extending between the inner cavity and the drill bit cutting face, forming a downward nozzle; and   c. a reverse passage extending between the inner cavity and the outer surface, forming a reverse nozzle,   
     the reverse nozzle directed away from the drill bit cutting face at a reverse nozzle upward angle. 
   
   
       2 . The drill bit of  claim 1 , the reverse nozzle upward angle being between about 45 and about 90 degrees. 
   
   
       3 . The drill bit of  claim 2 , the reverse nozzle upward angle being substantially 90 degrees. 
   
   
       4 . The drill bit of  claim 1 , the reverse nozzle directed tangentially at a reverse nozzle radial angle. 
   
   
       5 . The drill bit of  claim 4 , the drill bit adapted to have a direction of rotation, the reverse nozzle radial angle being between about 50 degrees to about 75 degrees opposite the direction of rotation. 
   
   
       6 . The drill bit of  claim 1 , wherein the drill bit is adapted to receive a flow rate of drilling fluid, the reverse flow nozzle adapted to flow between about 10 percent and about 40 percent of the flow rate. 
   
   
       7 . The drill bit of  claim 1 , wherein the drill bit is adapted to receive a flow rate of drilling fluid, the reverse flow nozzle adapted to flow between about 15 percent and about 25 percent of the flow rate. 
   
   
       8 . The drill bit of  claim 1 , wherein the drill bit is adapted to receive a flow rate of drilling fluid, the reverse flow nozzle adapted to flow less than or equal to about 25 percent of the flow rate. 
   
   
       9 . The drill bit of  claim 1 , wherein the drill bit is adapted to receive a flow rate of drilling fluid, the reverse flow nozzle adapted to flow less than or equal to about 15 percent of the flow rate. 
   
   
       10 . The drill bit of  claim 1 , wherein the drill bit is adapted to receive a flow rate of drilling fluid, the reverse flow nozzle adapted to flow less than or equal to about 10 percent of the flow rate. 
   
   
       11 . The drill bit of  claim 1 , wherein the drill bit is adapted to receive a flow rate of drilling fluid, the reverse flow nozzle adapted to flow less than or equal to about 5 percent of the flow rate. 
   
   
       12 . The drill bit of  claim 1 , wherein the reverse nozzle is adapted to discharge the drilling fluid proximate the drill bit cutting face. 
   
   
       13 . The drill bit of  claim 12 , wherein the reverse nozzle is adapted to discharge the drilling fluid a reverse nozzle distance from the drill bit cutting face, the reverse nozzle distance being between about 10 inches to about 12 inches (about 250 mm to about 300 mm). 
   
   
       14 . The drill bit of  claim 1 , wherein the drill bit is adapted to receive a flow rate of drilling fluid, the reverse nozzle adapted to discharge a portion of the drilling fluid at a reverse nozzle velocity and the downward nozzle adapted to discharge a portion of the drilling fluid at a downward nozzle velocity, wherein the reverse nozzle velocity is between about 50 percent and about 150 percent of the downward nozzle velocity. 
   
   
       15 . The drill bit of  claim 14 , wherein the reverse nozzle velocity is between about 75 percent and about 125 percent of the downward nozzle velocity. 
   
   
       16 . The drill bit of  claim 14 , wherein the reverse nozzle velocity is between about 90 percent and about 110 percent of the downward nozzle velocity. 
   
   
       17 . The drill bit of  claim 14 , wherein the reverse nozzle velocity is substantially 100 percent of the downward nozzle velocity. 
   
   
       18 . The drill bit of  claim 1 , wherein the drill bit is a PDC type drill bit. 
   
   
       19 . The drill bit of  claim 1 , wherein the drill bit is a roller cone drill bit.