PREDICTIVE VIBRATION MAPPING

Today, Drillers and Drilling Engineers are faced with significant challenges in effectively managing drilling parameters and mitigating risks associated with drilling dysfunction. An underlying risk that should be considered in any drilling program is the presence of excessive vibration in the BHA, especially those that coincide with the natural resonant frequencies of the drillstring. Excitation sources in drillstring, such as bits, reamers, stabilizers, mass imbalance, or mud motor nutation, can be compared to striking a guitar string: the excitation source induces vibrations that are amplified at critical rotation speeds that correlate to natural resonant frequencies of the drillstring. These intensified vibrations can manifest as drilling dysfunction in the form of bit-bounce (axial vibration), stick-slip (torsional vibration), and whirling (lateral vibration). Prolonged exposure to excess vibrations downhole at resonant RPMs can adversely affect penetration rate and elevate the risk of premature tool failure, twist-offs, and unplanned trips.