摘要
深层和超深层地层钻井通常存在钻井安全密度窗口窄和井控难度大等问题,传统的解决措施是对井下溢流进行早期监测,对于深井和超深井早期监测存在误差大及信息滞后等问题。鉴于此,根据井下微流量测量装置特点,以单个节流元件为基础,结合流体力学基本原理,建立了流量压差计算理论模型,并利用流体动力学模拟对理论模型进行了验证。研究结果表明:理论压差计算模型对微流量测量装置压差计算具有较高的精度和准确性;钻井过程中,流体流量增大,节流压差将会增大且增幅逐渐增大;井下环空流体稳定时,当井下发生井径缩小或溢流等复杂情况时,节流压差大于正常工况下节流压差,节流压差随井径缩小率或溢流量增大而增大且节流压差增幅逐渐增大。建议进一步建立微流量测量装置压差多相流模型,并对多种工况同时发生时井下微流量测量装置压差变化规律进行研究。所得结论可为深井和超深井钻探中溢流监测技术的现场应用提供参考。
Deep and ultra-deep formation drilling usually has problems like narrow density window and well control difficulty.The conventional solution,which monitors the early downhole overflow,has large errors and information lags for early downhole overflow monitoring in deep and ultra-deep wells.To address the problem,according to the characteristics of the downhole micro-flux measuring device,on the basis of single choke unit and combined with the basic principles of fluid mechanics,the theoretical model of pressure difference is established,and is verified by fluid dynamics simulation.The analysis results show that the theoretical pressure difference calculation model of the micro-flux measuring device has a high precision and accuracy.During the drilling process,with the increase of flow rate,the choke pressure difference will increase with gradually increased amplitude.Given the stable flow rate in annular,when hole shrinkage or overflow occurs in the well,the choke pressure difference is larger than that under normal conditions.The choke pressure difference increases with the hole shrinkage rate or the overflow flow rate.It is suggested to further establish multiphase flow pressure difference model of the micro-flux measuring device,and study the behaviors of the pressure difference of the downhole micro-flux measuring device when multiple working conditions occur simultaneously.The conclusions obtained can provide references for the field application of overflow monitoring technology in deep and ultra-deep well drilling.
作者
唐弢
马天寿
陈平
曾秀权
孙少林
Tang Tao;Ma Tianshou;Chen Ping;Zeng Xiuquan;Sun Shaolin(State Key Laboratory of Oil and Gas Reservoir Geology and Exploration,Southwest Petroleum University;Petroleum Engineering School,Southwest Petroleum University;Karamay Drilling Company,CNPC Xibu Drilling Engineering Company Limited)
出处
《石油机械》
北大核心
2019年第3期1-6,共6页
China Petroleum Machinery
基金
国家科技重大专项"深水高温高压气井井筒套管环空泄压工具研制"(2016ZX05028-001)
国家自然科学基金项目"地层压力随钻测试压力响应的数值模拟与物模试验"(41874216)
关键词
微流量测量装置
节流压差
溢流监测
漏失
井径缩小
micro-flux measuring device
choke pressure difference
overflow monitoring
well loss
hole shrinkage
