| 摘要 |
A method of forming a PDC drilling bit including the steps of imposing a side drilling direction on the bit, determining a total bit side force acting on the bit, computing a walk angle between the total side force and the side drilling direction, and modifying a configuration of cutters on the profile of the bit so as to change the walk angle to a desired angle. The step of determining a total side force includes the steps of determining a normal side force of the bit, computing a total cutter friction force, and combining the normal side force and the total cutter friction force so as to produce a total side force. The total cutter friction force is obtained by summing single cutter forces perpendicular to a direction of cut of the bit. The step of imposing a side drilling direction includes measuring a normal side force applied to the bit. The modification of the bit can be carried out by increasing or reducing the aggressiveness of the cutters facing outwardly on an outer surface of the bit or by replacing cutters on the bit with low friction pads.
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