| 摘要 |
A method for designing a fixed cutter drill bit, includes simulating the fixed cutter drill bit in an earth formation, determining radial and circumferential components of imbalance forces on the drill bit and a Beta angle between the radial and circumferential components of the imbalance forces during a period of simulated drilling, and adjusting a value of at least one design parameter for the fixed cutter drill bit at least based upon the Beta angle. To facilitate drill bit design, the Beta angle can be displayed to a drill bit designer. To improve performance, the method can include repeating the simulating, determining, and adjusting to change a simulated performance of the fixed cutter drill bit. A drill bit may be made according to the design resulting from the method. The simulation may include modelling of the drill bit dynamically drilling in the formation without constraining a centreline of the drill bit to be coaxial with a centreline of a bore hole. A design parameter may be adjusted to increase the proportion of time the Beta angle is at or near 180 degrees. |
