Research on Pore Pressure Detection While Drilling Based on Mechanical Specific Energy

The detection of the formation pore pressure while drilling is great importance to ensure safe operations. At present, dc-exponent concept mainly used detect drilling. based on theory shale compaction, which limited when in carbonate rocks. A mechanical specific energy (MSE)-based method proposed deep, complex intervals. that consumed by bit break and remove a unit volume rock can reflect effective stress situ. In this paper, torque weight (WOB) transfer model for estimating downhole WOB using drill string mechanics. Meanwhile, rotary speed positive displacement motors under compound are considered, total MSE modified. MSE-based was estimate region western Sichuan, there good agreement between detected measured pressure. results demonstrate accurate computed useful detecting deep