This paper introduces the novel concept of a flexible polycrystalline diamo
nd compact (PDC) bit and demonstrates its capability to reduce detrimental
vibration often associated with drag bits. The tilt flexibility, introduced
at the bit, decouples the dynamic motion of the bottomhole assembly (BHA)
from that of the bit, thus providing a dynamically more stable bit. The pap
er describes the details of a prototype 81/2-in. flexible bit design, labor
atory experiments, and field tests, which verify the concept.