气体循环钻井注气量计算与影响因素分析

依据气体循环钻井的工艺特点研究了循环钻井井筒及地面压力分布,在压力分布基础上结合最小动能法深入研究了封闭循环钻井关键点的选择,并研究了不同关键点对循环钻井注气量的影响。由于循环钻井为闭环钻井,利用循环钻进压力分布计算理论、气体P-V-T(压力-体积-温度)理论、最小动能携岩标准,研究了井口压力对注气量的影响。研究成果为循环钻井提供了理论基础,对循环钻井的现场应用具有积极的指导作用。

Calculation of Gas Injection Volume of Gas-cycling Drilling and Analysis on Its Influencial Factors

Based onthe technical characteristics of gas-cycling drilling, the wellbore and surface pressure distributions of the gas-cycling drilling were studied, and on the basis of the pressure distributional study and in combination with the method of minimum dynamic energy, the selection of key point of closed cycling drilling and effect of different key points on gas injectingvolume were studied. Because it was a closed well drilling, the theory of pressure distribution for cycling drilling, the theory of gas pressure-volume-temperature, the rock carrying standard of minimum dynamic energy were used to study the effect of wellhead pressure on gas injection volume. The result shows that it provides a theoretical basis for cycling drilling and provides a guidance of field application of gas-cycling drilling.