深水动态压井钻井井筒压力模拟  

Simulation on wellbore pressure during dynamic kill drilling in deep water

作　　者：付建红[1] 冯剑[1] 陈平[1] 韦红术[2] 刘正礼[2] 

机构地区：[1]西南石油大学油气藏地质及开发工程国家重点实验室,四川成都610500 [2]中国海洋石油有限公司深圳分公司,广东深圳518067

出　　处：《石油学报》2015年第2期232-237,共6页Acta Petrolei Sinica

基　　金：国家重大科技专项(2011ZX05026-001-04)资助

摘　　要：动态压井钻井技术可有效解决深水表层钻井过程中出现的溢流或井漏、井塌等井下复杂事故。为研究深水表层动态压井钻井过程中的压力变化特征,结合动态压井钻井基本原理,建立了动态压井钻井井筒物理模型,通过设定海水和加重钻井液的初始排量、排量随时间的变化率,推导出了变排量、变密度模式下的动态压井钻井井筒压力数学模型。根据墨西哥湾深水钻井实例数据,计算分析了动态压井钻井过程中环空密度、环空压力、环空压耗以及井底压力随时间的变化关系。结果表明,动态压井钻井技术的关键在于通过实时调整海水排量、加重钻井液排量控制混浆密度,进而控制环空液柱压力,达到深水表层安全钻井的目的;机械钻速是影响井底压力的重要因素,机械钻速越大,由岩屑产生的附加密度越大,井底压力越大。Dynamic kill drilling technology can effectively handle the well kick,loss of circulation or wellbore collapse during surface drilling of deep water.In order to figure out the pressure variation characteristics of dynamic kill drilling in deep water,this paper established a physical model of wellbore in dynamic kill drilling in combination with the basic theory of dynamic kill drilling.By setting up the initial flow rate and change rates of seawater flow rate and weighted drilling fluid flow rate,it derived the wellbore pressure computation model in variable flow rate and variable density scheme.According to the field data of Mexico Gulf deep water drilling,it calculated the annualar density,annualar pressure,annular pressure loss,and bottom hole pressure during dynamic kill drilling.The results demonstrated that the key step of dynamic kill drilling technology is controlling the mixture density by regulating the flow rate of sea water and weighted drilling fluid in timely,therefore,the annular fluid column pressure in drilling process is controlled,which is favorable to safety drilling in surface of deep water.Rate of penetration （ROP） has a great effect on bottom hole pressure in dynamic kill drilling.The additional density generated by cuttings increases with the increase of ROP,causing a larger bottom hole pressure.

关 键 词：深水 动态压井钻井 井筒压力 排量 密度 

分 类 号：TE24[石油与天然气工程—油气井工程]