Mud Pit Volume Trend Correction for Kick and Lost Circulation Monitoring
Mud pit volume is often used to monitor kick and lost circulation.During normal drilling operations,with the change of the wellbore volume and the exchange of drilling and formation fluids in the wellbore,the mud pit volume usually has a risk-like trend similar to that of kick and lost circulation,which leads to false alarms when existing kick and lost circulation monitoring methods are applied.In order to address this problem,the cau-ses of the risk-like trend of mud pit volume are analyzed,and mud pit volume change models under the drilling and tripping conditions are established,which are used to correct the risk-like trend of the mud pit volume and thus reduce the false alarm rate of kick and lost circulation monitoring.Then,the kick and lost circulation monito-ring model based on rule inference established in this paper is used to measure the impact of the risk-like trend of the mud pit volume on the kick and lost circulation monitoring.4,500 groups of drilling data measured on field were used to test the performance of the proposed models using the kick and lost circulation monitoring method based on rule inference.The results show that the false alarm rate of the risk monitoring method drops from 10.03%to 3.06%.
mud pit volumekick and lost circulation detectiontrend correctionrule inference