A Kick and Lost Circulation Monitoring Method Combining Bi-GRU and Drilling Conditions

The existing kick and lost circulation monitoring methods using pot volume and outlet flow of drilling fluids do not consider the influence of the pump on and off on the outlet flow, and pot volume of drilling fluids. So it can easily lead to false alarm. In order to address this problem, the correlation of drilling conditions with pot volume and outlet flow of drilling fluids was established, and an intelligent kick and lost circulation monitoring method combining a bidirectional-gated recurrent unit (Bi-GRU) and drilling conditions was proposed. The proposed model and other representative models for kick and lost circulation monitoring were tested by using the data collected from 23 wells. The experimental results show that the identification accuracy of the proposed model achieves 94.25%, which is superior to those of the other models. Compared with that of the Bi-GRU model without considering the drilling conditions, the false alarm rate of the proposed model drops from 12.52% to 1.12%. The proposed method reduces the false alarms caused by pump on and off states during kick and lost circulation monitoring, and these findings can provide technical support for safe drilling.