Cartridge for a rotary drill bit

Abstract

A cartridge for a drill bit of a rotary directional drilling system, the cartridge comprising: a cartridge housing having an inlet end for receiving drilling fluid from a drill string and an outlet end at which drilling fluid can exit the cartridge housing; a flow diverter configured to selectively control the flow direction of drilling fluid as the drilling fluid exits the cartridge housing; and a bearing assembly for supporting the flow diverter; wherein the bearing assembly comprises at least one bearing located at the outlet end of the cartridge housing.

1 . A cartridge for a drill bit of a rotary directional drilling system, the cartridge comprising:
 a cartridge housing having an inlet end for receiving drilling fluid from a drill string and an outlet end at which drilling fluid can exit the cartridge housing;   a flow diverter configured to selectively control the flow direction of drilling fluid as the drilling fluid exits the cartridge housing; and   a bearing assembly for supporting the flow diverter;   wherein the bearing assembly comprises at least one bearing located at the outlet end of the cartridge housing.   
     
     
         2 . A cartridge for a drill bit of a rotary directional drilling system, the cartridge comprising:
 a cartridge housing having an inlet end comprising an inlet for receiving a drilling fluid from a drill string and an outlet end comprising an outlet at which the drilling fluid can exit the cartridge housing;   a flow diverter configured to selectively control the flow direction of the drilling fluid as the drilling fluid exits the cartridge housing; and   a bearing assembly for supporting the flow diverter;   wherein the bearing assembly comprises at least one bearing located within the cartridge housing and positioned between the inlet of the cartridge housing and the flow diverter.   
     
     
         3 . The cartridge according to  claim 1 , wherein the bearing assembly comprises a first thrust bearing located at the outlet end of the cartridge housing. 
     
     
         4 . The cartridge according to  claim 3 , wherein the first thrust bearing is a conical bearing. 
     
     
         5 . The cartridge according to  claim 4 , wherein the first thrust bearing is configured to rotate about a central longitudinal axis of the cartridge. 
     
     
         6 . The cartridge according to  claim 2 , wherein the bearing assembly comprises a second thrust bearing located within the cartridge housing. 
     
     
         7 . The cartridge according to  claim 6 , wherein the second thrust bearing comprises a biasing member for biasing the position of the flow diverter in an axial direction. 
     
     
         8 . The cartridge according to  claim 2 , wherein the bearing assembly comprises a radial bearing located within the cartridge housing. 
     
     
         9 . The cartridge according to  claim 8 , wherein the radial bearing comprises a spacing member and two contact members arranged at each end of the spacing member; and
 wherein the contact members contact a spindle of the cartridge.   
     
     
         10 . The cartridge according to  claim 9 , wherein the contact members are made of tungsten carbide and/or polycrystalline diamond. 
     
     
         11 . The cartridge according to  claim 9 , wherein the flow diverter is mounted on the spindle, wherein the spindle is fixedly attached to the flow diverter and rotates with the flow diverter. 
     
     
         12 . The cartridge according to  claim 9 , wherein the spindle is rotatably mounted within the radial bearing. 
     
     
         13 . The cartridge according to  claim 12 , further comprising a support hanger, wherein the support hanger supports the radial bearing. 
     
     
         14 . The cartridge according to  claim 13 , wherein the support hanger is arranged proximal or adjacent to the flow diverter. 
     
     
         15 . The cartridge according to  claim 14 , wherein the support hanger comprises a plurality of apertures to allow drilling fluid to pass through the support hanger. 
     
     
         16 . The cartridge according to  claim 2 , wherein the flow diverter is rotatably mounted within the cartridge housing. 
     
     
         17 . The cartridge according to  claim 2 , wherein the cartridge is adapted to be received within a shank bore of a drill bit. 
     
     
         18 . A method for directional drilling of a well-bore in a formation, the method comprising:
 receiving a cartridge within an internal space of a drill bit, the cartridge comprising a cartridge housing having an inlet end for receiving drilling fluid from a drill string and an outlet end at which drilling fluid exits the cartridge housing; and a flow diverter to selectively control the flow direction of drilling fluid as the drilling fluid exits the cartridge housing; and   using the flow diverter to selectively direct at least a portion of the drilling fluid to one or more nozzles of a drill bit.   
     
     
         19 . The method according to  claim 18 , further comprising:
 connecting the flow diverter to a rotation control unit;   rotating the flow diverter relative to the rotation of the drill string in a rotational direction opposite to that of the drilling drill string; and   controlling the rotational position of the flow diverter to selectively direct at least a portion of the drilling fluid to one or more nozzles of a drill bit.   
     
     
         20 . The method according to  claim 18 , wherein the cartridge is received in a drill bit at a drilling site or drilling rig.