冀东油田大斜度井及水平井岩屑床厚度分析

针对冀东油田在大斜度井及水平井钻井过程中岩屑颗粒易在井壁低边堆积形成岩屑床、造成井下复杂情况并影响后续作业这一问题,对井下环空岩屑床形成与否及厚度大小、影响钻井液携岩效果的主要因素如井斜角、钻井液环空返速及性能、钻杆偏心及旋转等问题进行了研究,建立了环空岩屑床厚度计算模式,并用该模式对冀东油田高104-5平56井进行了具体分析。分析表明:该井二开钻进时预测最小排量与实际排量接近,钻进过程比较安全;三开钻进时上部二开井段实际排量远低于预测最小排量,致使该段岩屑床厚度达到危险情况。建立的岩屑床厚度计算模式的计算结果与实际情况比较吻合,该模式的应用可为现场施工人员了解井下岩屑床厚度提供参考。

Cuttings bed thickness analysis of high angle deviated well and horizontal well in Jidong Oilfield

The problem on cuttings bed accumulated easily by cuttings particle at low boundary of well wall in high angle deviated well and horizontal well while drilling in Jidong Oilfield,results in underground troubles and influencing subsequent operation.Aiming at the problem,whether underground annular cuttings bed forms,its thickness size and the main factors influencing carrying rock effect of drilling fluid such as well decline,annular velocity and performance of well drilling fluid,eccentricity and rotation of drill pipe,and so on are studied.Thickness calculation model of annular cuttings bed,by which high 104 flat 56 well in Jidong Oilfield is analyzed concretely is established.It shows that,the prediction for minimum displacement accesses to actual displacement on second open drilling in so the drilling process is relative safe.Actual displacement of upper second open well segment far lower than forecasting minimum displacement in third drilling in leads to this cuttings bed in dangerous state.Furthermore,the calculation results of cuttings bed thickness calculation model established are consistent with actual situation so the model application may provide reference for field constructors knowing underground cuttings bed thickness.