1. Five Blades and Capacious Flume Symmetrical parabola crown profile, asymmetrical blades, the cutters are distributed as curve, more assistant cutters inserted and bit gauge is designed spiral. Flow roomage is optimal designed so that mud and rock granule can be clear easily in drilling. 2. High wear resistance cutters. High performance PDC cutters optimal design highly decrease the cutting resistance, largely increase the life of bit. 3. Oppose-circumnutation design. The load on bit is balanced, and the journal libration is decreased as well as good performance in directional drilling. 4. This series of bits are suitable for medium to medium-hard formation.
