| 摘要 |
A drill bit comprises a shank member ( 31 ), a bit body ( 32 ) provided with cutters ( 33 ) and flexible material ( 35 ) between the shank ( 31 ) and the bit body ( 32 ) allowing relative tilting movement therebetween to reduce adverse effects caused by vibration of the bit. In other embodiments, flexible material is provided between the bit body and the cutters. In further embodiments, the flexible material may be provided in a tiltable sub-assembly for incorporation in a drilling above the drill bit. An apparatus for simulating drilling conditions is also provided. |
