Abstract:PDC drill bit manufactured by infiltration process with vibration does not work effectively in cobble interbed, a new type of PDC bit was developed because of the characteristics of high hardness, interbed, inhomogeneity and high abrasiveness. The structure of bit crown is of outside parabola-inside cone features with auxiliary cutting edges; and PDC is of non-plane, that is, multi groove binding has been adopted. According to the new design, 3 bits were produced and to be tried in 3 wells separately. It shows drilling efficiency increased by 26%, and the new type of PDC bit has advantages in drilling cobble formation.