气体钻井条件下工程异常监测方法

Monitoring methods for abnormal engineering under the condition of gas drilling

气体钻井是使用气体作为循环介质或作为循环介质一部分进行钻井的工艺技术,属于低压欠平衡钻井方式。由于工艺流程和循环介质与常规钻井存在差异,常规钻井条件下钻井异常预测技术不能完全满足气体钻井施工要求,为准确预测地层出水和防止发生井下燃爆等气体钻井特有的工程复杂状况,配套安装了温湿度传感器和红外线CO分析仪及其他相关传感器,并结合实际工作总结了气体钻井过程中地层出水、井下燃爆等工程异常的录井参数响应模式,进一步完善了工程异常监测方法,为保证气体钻井顺利施工提供了技术保障。

Gas drilling is a technology to use gas as a circulating medium or as a part of the circulating medium to drilling, which belongs to low pressure underbalanced drilling. Due to the differences with conventional drilling in technological process and the circulating medium, under the conventional drilling conditions, the prediction technology for drilling anomalies can′t fully meet the requirements of gas drilling operation. Thus, in order to predict formation water output and prevent specific engineering complex situations, such as downhole blasting, the temperature and humidity sensors, infrared CO analyzers and other related sensors were installed. With the actual operations, the authors summarized the impact modes of engineering anomalies, such as formation water output, downhole blasting on mud logging parameters, which further improve the abnormal engineering monitoring methods and provide technical supports to ensure successful gas drilling.