Evaluation Of Formation Properties And Bit Efficiency Based On Mechanical Specific Energy During Drilling

With the development of oil and gas exploration,more and more deep and complex formations have been drilled,which has brought many new challenges to drilling technology.How to use logging data to make fast,real-time and accurate interpretation,diagnosis and optimization of formation properties and drilling construction state has become especially important.This thesis mainly analyzes from the angle of drilling energy consumption,and uses the theory of energy conservation to integrate logging engineering parameters such as drilling pressure,rotation speed,torque,mechanical drilling speed,hydraulic parameters and bit size into a single mechanical specific energy parameter,and establishes a drilling while drilling evaluation method of formation physical property and bit efficiency based on mechanical specific energy.Firstly,considering the response characteristics of drilling engineering parameters under different drilling tool combinations and well types,the corresponding mathematical and physical model of mechanical specific energy is established,,and a method for predicting and monitoring the basic value line of mechanical specific energy is put forward by using laboratory experiment method,logging data method and logging monitoring method.Secondly,the longitudinal and transverse wave time difference experiment,porosity experiment and micro drill bit drilling experiment were carried out,and the characteristics of drilling pressure,torque and mechanical specific energy of rocks with different physical characteristics,and establish the relationship model between mechanical specific energy and formation physical properties,so as to quantitatively evaluate formation physical properties through mechanical specific energy while drilling.Finally,the corresponding characteristics of the mud hole,vibration and bit wear of the drilling well in the intersection of the mechanical energy value and the feed rate of the drill bit are studied.The real-time monitoring and forecast by using logging data.The results show that the mechanical specific energy theory can be used for qualitative and quantitative analysis and evaluation of formation physical properties while drilling,and real-time prediction of drilling construction status during drilling,which has certain guiding significance for improving drilling efficiency and oil and gas discovery rate.