Analysis on Drill String Vibration Signal of Stick Slip and Bit Bouncing

Abstract

In drilling engineering, drill string premature damage are frequently observed, resulting in drilling cost and cycle prolonged. Researches show that, the common phenomenon of drill string vibration is the main cause of premature damage, thus more and more attention is paid to research on drill string vibration. Real time monitor and analysis on drill string vibration has important implications for vibration control, complex prevention, downhole condition prediction and drilling parameter optimization. Cases of vibration signal of stick slip and bit bouncing are collected and analyzed with Fourier transform, and frequency spectrum characteristic of vibration signal is obtained. The results show that, the vibration signal can reflect bottom hole condition of drill string, thus to predict premature damage of drill string and decrease drilling cost.
Key words: Drill string vibration; Stick slip; Bit bouncing; Signal characteristic