关键词: 牙轮钻头, 动力学特性, 钻柱, 耦合振动, 岩石, 相互作用, 数学模型, 仿真软件

Abstract: The dynamics of roller cone bit under the interaction of drilling string,bit and rock during the drilling process was investigated. According to Hamilton's principle and finite element method,the models for vertical,lateral and torsion coupled vibration of full-hole drilling strings were established.On the basis of many experiments,the mechanics model for the interaction of roller cone bit and rock was established.On the system dynamics,the dynamics model for roller cone bit under the interaction of drilling string and rock was established. The solving method for the nonlinear system dynamics model of roller cone bit was presented.The dynamics emulation software for bit system was finished. Using the emulation software,the emulation tests under different drilling operational parameters,geometric parameters of drilling tool and different rock property were finished.The research work can help reveal the motion rule of drilling string and bit,dynamics characters and failure meachanism.It also offers theoretical reference and technical basis for scientific prediction and control of well trajectory.

Key words: roller bit, dynamics property, drilling string, coupled vibration, rock, interaction, mathematical model, emulation software