Drilling efficiency through beneficial management of rock stress levels via controlled oscillations of subterranean cutting elements

摘要

A device and system for improving efficiency of subterranean cutting elements uses a controlled oscillation super imposed on steady drill bit rotation to maintain a selected rock fracture level. In one aspect, a selected oscillation is applied to the cutting element so that at least some of the stress energy stored in an earthen formation is maintained after fracture of the rock is initiated. Thus, this maintained stress energy can thereafter be used for further crack propagation. In one embodiment, an oscillation device positioned adjacent to the drill bit provides the oscillation. A control unit can be used to operate the oscillation device at a selected oscillation. In one arrangement, the control unit performs a frequency sweep to determine an oscillation that optimizes the cutting action of the drill bit and configures the oscillation device accordingly. One or more sensors connected to the control unit measure parameters used in this determination.