Abstract:
A method and apparatus for monitoring the wear on a rotary drill bit including means for measuring the revolutions of the drill string and the weight on the bit, and for obtaining the product thereof, such product being a measure of the wear on the bit. A pulse train is generated having a pulse rate proportional to the weight on the bit. Controlled portions of the pulse train are registered in a counter, the portions being proportional in duration to the number of revolutions turned by the bit, with the result that the accumulated count registered provides at any time the integrated product of weight and revolutions, as a measure of bit wear.