Application Of Coiled Tubing Drilling Bridge Plug Process Simulation And The Drill Grinding Parameters Optimization

In recent years,with the transformation of the general oil and gas reservoirs and the increasing demand for unconventional oil and gas reservoirs,the optimization of the grinding parameters of the coiled tubing drill-grinding bridge plug has been widely studied.Coiled tubing has the characteristics of high strength and high toughness.Compared with the traditional tubing operation,it has the advantages of short operation period,high efficiency and convenient transportation especially in the special downhole operation.The drilling rate equation and wear equation analysis and parameter optimization for coiled tubing depth,exert drilling pressure,transmission medium displacement,analysis and evaluation of these to provide a theoretical basis to ensure the safe and reliable operation of various downhole tubing.This paper selects the coiled tubing drilling bridge plug as the research object,bases on cutting principle and elastic-plastic mechanics,aims at drill and the overall spatial structure of bridge plug,the stress analysis of the composite bridge plug made of composite bridge plug is carried out.And the numerical simulation results are obtained under the action of drilling pressure and torque.Considering drilling pressure,drilling speed,the characteristics of the bridge plug,hydraulic factors and the wear of the screw drill,the specific drilling rate equation and the bit wear equation were established.In the drill-grinding single bridge plug case,due to the limitation of the various factors in the construction of drill-grinding bridge plug,drilling pressure and displacement is the main control variables on the drilling speed,according to the current situation analysis of the effect of drill pressure and displacement of drilling speed.In the hierarchical operation,need a trip to drill a plurality of bridge plugs,in this condition,analyzes the relationship between the drilling pressure and drilling time,displacement and drilling time,drilling pressure and the maximum drilling plug length,so as to determine the optimal method of plurality of plugs drill-grinding,drilling pressure and displacement.According to the requirement of parameters optimization of the drill-grinding bridge plug,the mechanical properties of the main structural materials of the bridge plug were tested,the test object is the main supporting structure material of the bridge plug.Based on the compression test and torsion test,the grinding parameters of single plug and single pipe string under different working conditions were determined,and the drill-grinding time and the limit drill-grinding depth are obtained.