Early gas kick detection is an important measure to ensure well control safety. In this paper, firstly, a new two-phase flow model was developed to accurately describe the transient annular pressure responses at the PWD tool during the gas influx. Secondly, a Dual-Measured-Points Early Gas Kick Detection Method was proposed based on the consistency and discrepancy between the pressure responses of two PWD tools. The results of case research indicated that the annular pressure increased and changed periodically with time in the initial stage of gas kick and then declined approximately linearly after the gas-liquid interface reached the PWD tool. Additionally, the proposed gas kick detection method could significantly reduce the chances of the gas kick misdiagnosis and improve the reliability of the gas kick detection. Moreover, the gas kick confirmation time (GKCT) obtained by the proposed method was 2–7 min, and the corresponding gas kick confirmation volume (GKCV) was 0.3–0.5 m³. The GKCT diminished with the increase in the formation permeability and the bottomhole pressure difference and with the decrease in the borehole size and the well depth.

中文翻译：

---

基于两个PWD工具的压力响应的双测点早期气塞探测方法的开发

尽早发现天然气踢是确保井控安全的重要措施。在本文中，首先，开发了一种新的两相流模型，以准确描述PWD工具在气体涌入期间的瞬态环形压力响应。其次，基于两个PWD工具的压力响应之间的一致性和差异，提出了一种双测点早期气塞探测方法。案例研究结果表明，在气涌初始阶段，环形压力随时间周期性地增加和变化，然后在气液界面到达PWD工具后近似呈线性下降。另外，所提出的气塞检测方法可以显着减少气塞误诊的机会并提高气塞检测的可靠性。此外，³。GKCT随地层渗透率和井底压力差的增加以及井眼尺寸和井深的减小而减小。