| 摘要 |
A drill bit (110 ) with at least one 'plural set' of cutting blades (137,138), and a number of 'single set' blades (139-142). The plural set of cutting blades (137,138) have redundant cutter element arrangements (150), that is to say the cutter elements have equivalent longitudinal and axial spacing on the blade and from the longitudinal axis (111) of the bit. The single set blades (139-142) have unique cutter element arrangements that are different from every other blade on the bit. This asymmetric configuration generates an imbalance which will help push the drill bit against the side of the borehole which will stabilize the bit and reduce the likelihood of mechanical failure. |
