随钻扩眼钻具组合与钻井参数优化研究

鉴于国内现有随钻扩眼系统钻具组合与钻井参数优化研究缺乏,同时考虑领眼钻头及扩眼器几何结构、地层岩石强度及钻井参数等3种影响因素的计算模型少有报道,以及扩眼系统扭矩分配比计算方法缺失等现状,通过建立模型分析了领眼钻头钻压和扭矩分配比随钻具组合、钻柱转速及地层强度的变化规律,进行了钻前不同扩眼钻具组合对比与优选以及随转扩眼...

Study on Bottom Hole Assembly and Drilling Parameter Optimization for Reaming While Drilling

Domestic studies on bottom hole assembly(BHA)and drilling parameter optimization for reaming while drilling(RWD)are lack of the calculation model which considers three influence factors(i.e.,geometric configuration of pilot bit and reamer,formation rock strength and drilling parameter)and the method for calculating the torque distribution ratio of reaming system.In this paper,a model is established to analyze the variation laws of weight on bit(WOB)and torque distribution ratio of pilot bit with BHA,WOB,rotation speed and formation strength.In addition,different reaming BHAs are compared and selected before the drilling and RWD case is analyzed.The results show the model for calculating the WOB and torque distribution ratio of pilot bit in the process of RWD is developed based on the model for calculating rock breaking mechanical energy,cutting depth and friction coefficient of cutting tool.What’s more,the optimization process of drilling parameters of RWD system is put forward,and the model for calculating the output WOB and torque of RWD system is established.The research conclusions can provide the theoretical support for drilling parameter optimization and automatic drilling in the process of RWD.