REVIEW ON DRILL BIT SELECTION METHODS

Rational selection of the bit type is of major importance in achieving high penetration rates and reducing drilling comprehensive cost. The primary methods for bit selection in recent years at home and abroad are summarized and evaluated. At present, bit selection methods can be classified into three types. The first is called bit usage effect method by which the bit selection was decided by parameters, which could reflect the performance of the bit. The second is named rock mechanics parameter method by which the bit selection was decided both by one or several rock mechanics parameters of the format ions, which would be countered in the drilling process, and by manufacturers’ product guides. The last is comprehensive method. Combined bit usage effect with rock mechanics parameters, the bit type is selected by use of this method. The primary principle of each method was described. At the same time, the shortcomings of each method were analyzed. Finally, key problems and the development trend in this field are pointed out.