基于工程参数变化趋势异常诊断的卡钻实时预警方法

Real-time early warning of pipe sticking based on abnormal diagnosis of engineering parameter change trend

摘要:

川南工区是中石化重点页岩气勘探开发工区，该工区地层压力系数高、钻井地质条件苛刻，导致该工区钻井复杂、故障频发，其中卡钻故障最为突出，严重制约了川南页岩气的安全高效开发。现有卡钻识别技术存在监控信息综合利用能力差、风险预警不及时、主观性强等问题。本文通过分析钻井作业过程中卡钻故障的专家知识判断，确定了卡钻风险对应的关键表征参数，并研究了卡钻发生位点的关键表征参数的变化趋势，得到了相应的变化规律；在此基础上建立了基于工程参数变化趋势异常诊断的卡钻实时预警方法。选取WY-XX井为实例进行分析，软件预警结果与实际井下风险相吻合，验证了模型的准确性和可靠性，准确率达83%。

Abstract:

South Sichuan work area is a key shale gas exploration and development area of Sinopec. The high formation pressure coefficient and harsh drilling geological conditions in this work area lead to complex drilling and frequent failures， among which sticking fault is the most prominent which seriously restricts the safe and efficient development of shale gas in South Sichuan. There are some problems in the existing technology， such as poor comprehensive utilization of monitoring information， not timely risk warning and strong subjectivity. In this paper， through the analysis of the expert knowledge judgment of sticking fault in the drilling process， the key characterization parameters corresponding to the risk of sticking are determined， the change trend of the key characterization parameters at the location of sticking is studied and the corresponding change rules are obtained. On this basis， a real-time early warning method for sticking fault based on abnormal diagnosis of engineering parameter change trend is established. Well WY-XX is selected as an example for analysis， as a result， the warning results by this software is consistent with the actual downhole risk which verified the correctness and reliability of the model with the success rate of 83%.