摘要
根据质量守恒及动量守恒方程,建立了微流量控制钻井过程中的节流阀调节的限压/限时动作模型,通过计算机编程对其求解,提出了有模型的节流阀控制环空波动压力方法。计算结果表明:环空中最大波动压力可通过限压/限时调节控制;节流阀控制环空最大波动压力均遵循省时不省压、省压不省时的规律,随限时减小环空波动压力高峰值增加,随限压减小节流阀调节时间增大,随井底溢流量增大,节流阀驻阀开度减小;节流阀关阀时间延长3.2s,节流阀开度低谷值增大2.5度,环空所受波动压力高峰值减小0.3MPa;限压/限时调节控制核心是采用触探式反复调节的方式控制节流阀开度。
During managing pressure drilling operations, precise control of annulus pressure based on the no-model and self-adjustment throttle valve control method cannot be achieved. In this paper, a time limited/pressure limited model for throttle valve control is established according to the mass conservation equation and momentum conservation equation. Control of throttle valve based on theoretical model is realized by solving the numerical solutions of the model by compiling the computer program. Calculation results show that the maximum fluctuating pressure can be controlled by the time limited/pressure limited adjustment. The maximum throttle control annulus pressure fluctuations are obey the law that saving pressure and wasting time or saving time and wasting pressure. With the decrease of the limited time, the maximum fluctuating pressure will be increased. With the decrease of limited pressure, the throttle valve adjustment time should be increased. With the increase of influx rate, the opening of throttle valve after the adjustment should be decreased. When the time for adjust throttle is prolonged to 3.2s, the minimum opening of throttle is increased 2.5 degrees, and fluctuations pressure is reduced 0.3MPa in annulus. The key of time limited/pressure limited control is to control the opening of throttle valve by repeated adjustment.
出处
《应用力学学报》
CSCD
北大核心
2017年第6期1014-1018,共5页
Chinese Journal of Applied Mechanics
基金
国家重大专项(2016ZX05038-006)
中石化石油工程公司科技项目(SG15-08K)
关键词
微流量控制钻井
反问题
节流阀动作
波动压力
限压调节
限时调节
micro flow control drilling
inverse problem
fluctuating pressure
pressure limited control
time limited control
