System and method for monitoring wear of a drill bit

Abstract

The present disclosure relates to a system for monitoring wear of a drill bit, comprising: a drill bit provided with: a cutting surface; an internal matrix; and a channel at an internal region of the drill bit, beneath the cutting surface; a source of pressurised drilling fluid, the internal matrix of the drill bit being connected to the source of pressurised drilling fluid, and configured to receive drilling fluid from the internal matrix; and a monitor for monitoring the pressurised drilling fluid; wherein the channel is configured to release drilling fluid to an exterior of the drill bit when the cutting surface above the internal region is worn away to expose the channel. There is also provided a drill bit and method associated with the system.

1 . System for monitoring wear of a drill bit, comprising:
 a drill bit provided with:   a cutting surface;   an internal matrix; and   a channel at an internal region of the drill bit, beneath the cutting surface;   a source of pressurised drilling fluid, the internal matrix of the drill bit being connected to the source of pressurised drilling fluid, and configured to receive drilling fluid from the internal matrix; and   a monitor for monitoring the pressurised drilling fluid;   wherein the channel is configured to release drilling fluid to an exterior of the drill bit when the cutting surface above the internal region is worn away to expose the channel.   
     
     
         2 . System according to  claim 1 , further comprising one or more drilling fluid outlets for supplying drilling fluid from the internal matrix to the exterior of the drill bit. 
     
     
         3 . System according to  claim 12 , wherein the channel is enclosed within the drill bit. 
     
     
         4 . System according to  claim 1 , wherein the channel is positioned at a predetermined distance from the cutting surface, such that exposure thereof to the exterior occurs due to wear of the cutting surface greater than or equal to the predetermined distance. 
     
     
         5 . System according to  claim 1 , wherein the monitor is a pressure monitor for measuring the pressure of the pressurised drilling fluid. 
     
     
         6 . System according to  claim 1 , wherein the channel extends closest to the cutting surface beneath a shoulder or nose section of the drill bit. 
     
     
         7 . System according to  claim 1 , wherein the channel comprises at least one branching point. 
     
     
         8 . System according to  claim 1 , wherein the monitor is positioned remotely relative to the drill bit. 
     
     
         9 . System according to  claim 1 , wherein the monitor comprises a sensor for automatic detection of variation of pressure. 
     
     
         10 . A drill bit, comprising:
 a cutting surface;   an internal matrix connectable to a source of pressurised drilling fluid; and   a channel at an internal region of the drill bit, beneath the cutting surface, configured to receive drilling fluid from the internal matrix, the channel extending to an internal region of the drill bit;   wherein the channel is configured to release drilling fluid to an exterior of the drill bit when the cutting surface above the internal region is worn away to expose the channel.   
     
     
         11 . The drill bit according to  claim 10 , further comprising one or more drilling fluid outlets for supplying drilling fluid from the internal matrix to the exterior of the drill bit. 
     
     
         12 . The drill bit according to  claim 10 , wherein the channel is enclosed within the drill bit. 
     
     
         13 . The drill bit according to  claim 10 , wherein the channel is positioned at a predetermined distance from the cutting surface, such that exposure thereof to the exterior occurs due to wear of the cutting surface greater than or equal to the predetermined distance. 
     
     
         14 . The drill bit according to  claim 10 , wherein the channel extends closest to the cutting surface beneath a shoulder or nose section of the drill bit. 
     
     
         15 . The drill bit according to  claim 10 , wherein the channel comprises at least one branching point. 
     
     
         16 . Method of monitoring wear of a drill bit, the method comprising the steps of:
 providing the drill bit with a channel configured to be exposed to the exterior of the drill bit by wear of the drill bit;   monitoring pressurised drilling fluid; and   detecting a change in the pressurised drilling fluid, indicative of exposure of the channel to the exterior.   
     
     
         17 . Method according to  claim 16 , wherein the method is applied to the system of  claim 1 . 
     
     
         18 . Method according to  claim 16 , wherein the drill bit is the drill bit of  claim 10 . 
     
     
         19 . Method according to  claim 16 , wherein the step of detecting a change comprises detecting a change in pressure of the pressurised drilling fluid, and optionally comprises detecting a drop in pressure of the pressurised drilling fluid for a predetermined time interval. 
     
     
         20 . Method according to  claim 16 , further comprising an additional step of emitting an audible and/or visual alarm when the change in the pressurised drilling fluid, indicative of exposure of the channel to the exterior, is detected.