Abstract：High frequency torsional impact drilling is a new emerging drilling technology, which can enhance the drilling efficiency by a large margin. But it is not popularized interiorly due to ignorance of its rock breaking mechanism. A 3D non-linear dynamic simulation model of dynamic rock breaking with full gauge PDC bit is established, in which the finite element model is created based on elastoplastic mechanics and rock mechanics. The constitutive relation of rock is controlled by Drucker-Prager law and plastic strain is adopted to judge the rock breaking. The dynamic rock breaking process of bit under high frequency torsional impact in tough formation is analyzed. Results show that most of the rock elements are damaged by the pulling stress, with which the ROP are enhanced greatly. The high frequency torsional impact mitigate stick-slip vibration effectively and increase the rock breaking efficiency greatly. The research achievements provide theoretical basis for deep understanding and popularizing the high frequency torsional impact drilling technology.
祝效华;汤历平;童 华. 高频扭转冲击钻进的减振与提速机理研究[J]. , 2012, 31(20): 75-78.
ZHU Xiao-hua;TANG Li-ping;TONG Hua. Study on damping and speed-raising mechanism of high frequency torsional impact drilling. , 2012, 31(20): 75-78.
2012, Vol. 31 
