Research And Application Of Bit Selection For Marine And Continental Shale Gas Drilling

In the process of drilling,the reasonable selection of drill bit and drilling parameters is a n important link to increase drilling speed and reduce drilling cost.Shale gas drilling is still the f irst time in Henan marine and continental strata.This study is an exploratory work carried out thr ough statistical analysis of the actual drilling data in this area.In this paper,the current research methods of bit selection at home and abroad are inves tigated,the drillability characteristics of layers in the region are described,and the usage of drilli ng bits in the region has been statistically analyzed.By using the method of formation drillabilit y optimization,the drillability values of different formations are obtained,and the average rock d rillability values and the average well depth in layers are regressed by using the linear equation,t hus establishing a regional formation rock drillability numerical gradient formula model.Accord ing to the regional stratum drillability gradient law and the corresponding distribution range of st ratum values,combined with the study of bit performance data provided by bit vendors,a metho d for optimizing bit drillability in the regional stratum is formed.At the same time,using the par ameter data obtained from actual drilling,the performance of the drill bit is evaluated by means o f average mechanical penetration rate method,bit benefit index method and specific energy meth od.Combined with the comprehensive comparative analysis of the two methods,the final drill b it optimization model is constructed.The drill bit types suitable for the Quaternary,Neogene and Paleogene strata in the regi on were determined by numerical calculation of the optimization model,and the drill bit types su itable for the upper strata of Triassic Sanggou Formation,Liujiagou Formation and the lower stra ta of Liujiagou Formation were found.The problem of bit selection in complex formations of th e Upper Permian Sunjiagou Formation and Pingdingshan Formation was solved,the bit selection in complex formations of the Upper Permian Sunjiagou Formation and Pingdingshan Formation was solved,the bit selection scheme for shale gas drilling technology in marine and continental f ormations in Henan region was realized,the effective assembly process of drilling tools was furt her optimized,and the drilling efficiency was improved.