Simulation And Experiment Of Drill String Frictional Torque In Horizontal Well

With the increasing global demand for oil and gas resources,the number and scale of horizontal wells and extended-reach wells are also increasing.Horizontal wells can more efficiently extract oil and gas from geological reservoirs than traditional vertical wells,and can increase production rates and extend the life of reserves.However,the development of horizontal wells is a complex process that requires the use of high-end drilling technology and equipment,and the exploitation of horizontal wells also requires the use of advanced oil recovery technologies.Due to its special curved section and horizontal section,the friction torque of the drill string will become a key factor restricting whether the horizontal well can be drilled normally.The model calculation and simulation analysis of the friction torque of the horizontal well has become a feasible way to verify the horizontal well drilling It is an important method for troubleshooting and troubleshooting.In this paper,the method of combining calculation,simulation and experiment is used to carry out the research on the friction torque of horizontal well drill string.The main contents are as follows:(1)Summarized the friction torque calculation model of conventional horizontal wells,used MATLAB to program the calculation model,and analyzed the large hook load.The analysis shows that under the lowering condition,the Aadnoy model error is the smallest in the horizontal section,and the error is the smallest when the friction coefficient is around 0.15 in the stable slope section.Under the lifting condition,the Johancsik model and the Yan model are relatively close,and the accuracy of the model gradually decreases with the increase of the friction coefficient.The Johnsick model is more stable and accurate when it is lowered,and the Aadnoy model is more accurate when it is lifted.(2)Based on the SOLIDWORKS and ADAMS software,the whole well model of the horizontal well was established.During the modeling,different horizontal well models were established according to the hoisting and lowering conditions and different drill string unit lengths.When lifting,the drill string is first located in the horizontal section,and when it moves to the wellhead,the simulation data is recorded.The simulation analysis found that the smaller the length of the drill string unit,the closer the simulation result is to the calculated value of the model,but finally the drill string unit with a length of 1 m was selected comprehensively.(3)Comparing and analyzing the simulated analysis results of horizontal well friction torque under different drill string unit lengths and different working conditions with those calculated by MATLAB,the results show that when lifting,the simulated measured hook The load value is greater than the calculated value of the model in any well section;when lowering,the hook load measured by simulation is smaller than the hook load calculated by the calculation model in the vertical section.Moreover,the error between the calculation results of the simulation model and the calculation results of the calculation model is small,thus proving the reliability and correctness of the simulation model.(4)Use the drill string friction torque test experimental device to obtain the contact force of the drill string in the curved section and the axial force at the junction of the curved section and the vertical section during lifting,and compare it with the contact force at the same position of the simulation model.The results show that the trends of contact force and axial force at the same position are the same,which proves that the simulation model has certain accuracy.Through the research in this paper,we can compare and correctly select the appropriate friction torque model,which has certain guidance and practical significance for the design of horizontal well drilling,drilling feasibility analysis,and increasing the success rate of drilling.