Friction Torque Analysis And Ultimate Extension Prediction Of Three-Dimensional Horizontal Well Of Shale Oil Friction Torque Analysis And Ultimate Extension Prediction Of Three-Dimensional Horizontal Well Of Shale Oil

With the development of unconventional complex oil and gas reservoirs such as shale oil,long horizontal well technology has become an important core technology.In the process of drilling long horizontal Wells,the problem of drag and torque is particularly prominent.Therefore,it is of great significance to carry out research on drag and torque analysis and limit extension prediction of horizontal Wells in shale oil.Based on the actual drilling conditions of shale oil RIGS in Longdong oilfield,this paper firstly analyzes the main technical difficulties in drilling and completion of long horizontal well groups.Secondly,the existing drill string mechanical model is analyzed and perfected.According to the fact that drill string mechanics of horizontal well is nonlinear,the static finite element mechanical analysis model of the whole drill string of horizontal well is established by using drill string finite element method,and the drill string mechanical equation and specific solution method are given.At the same time,considering the existing calculation model of drag and torque,the targeted three-dimensional force analysis and calculation software of horizontal well is researched and developed,which can carry out statical analysis and calculation of the tensile and torsional strength of drill tool under different working conditions.Based on the actual working conditions,the software is analyzed and compared with the calculation results of WellPlan and the field measured drag and torque values.The maximum error of software prediction is 7.5%,which has high prediction accuracy.Thirdly,by simulating the field design conditions of shale oil,the friction,torque and lateral force of horizontal Wells with different target forward distances are compared and analyzed under the same extension capacity,and the optimal limit construction of horizontal Wells with 500 meters target forward distances is determined.Taking the horizontal well 500 meters in front of the target as an example,the maximum extension capacity of the horizontal section under the current construction capacity of tools and RIGS is calculated.The research results can be used to guide the drilling of long horizontal section of shale oil in Longdong oilfield.