摘要
固井水泥浆凝结成水泥石过程中的体积收缩会导致水泥石与套管和井壁之间耦合力降低,甚至产生微间隙从而影响固井质量,严重时会导致环空带压。憋压候凝不仅能提高固井质量,而且解决了水泥浆失重引起的压稳问题。在地层承压能力不能满足一次性憋压的情况下,可根据水泥浆在凝结过程中具有塑性体的特征,分时段逐渐提高憋压值以实现环空憋压。分段逐级憋压通过井口把压力分时段传递到正处于凝结区域的水泥浆,正处于凝结区域上部的浆体的凝结时间、高度、密度对传压能力影响较大。上部浆柱凝结时间越长,压力传递能力越低;上部浆柱高度越大,压力传递能力减小;相同的凝结时间和浆柱高度,压力传递能力随上部浆柱密度增加而降低。PX2井177.8 mm+193.68 mm尾管固井作业中采用了分段逐级憋压技术,固井质量合格率达到98.1%,环空无气窜现象,该技术不增加成本,具有较大的推广价值。
After the cement slurry is condensed into cement stone,the volume of cement stone decreases.The reduced volume will lead to the reduction of the coupling force between the cement stone and the casing and the well wall,and even produce micro-gap,which will affect the cementing quality,and even lead to annulus pressure.Holding pressure and waiting for cementing can not only improve cementing quality,but also solve the problem of pressure stability caused by weight loss of cement slurry.However,the pressure bearing capacity of many formations can not meet the requirements of one-time pressure holding.At this time,according to the characteristics of plastic body in the process of cement slurry setting into cement stone,the pressure holding value is gradually increased in different periods to achieve the purpose of annulus pressure holding.Therefore,in order to effectively transfer the pressure from the wellhead to the cement slurry setting area,it is necessary to consider the influence of different height,setting time and density of cement slurry in the upper part on the pressure transmission capacity.The results show that the pressure transmission capacity of cement slurry decreases with the increase of setting time,and decreases with the increase of slurry column height;At the same setting time and slurry column height,the pressure transmission capacity decreases with the increase of slurry column destiny.Based on the above research,the field test has been carried out in 177.8 mm+193.68 mm liner cementing operation of Well PX2.Through testing,the qualification rate of cementing quality reaches 98.1%,and there is no gas channeling in the annulus.The"stage by stage pressure holding"cementing technology can not only improve the cementing quality,but also reduce the occurrence rate of gas channeling without increasing the cost,and has great popularization value.
作者
符豪
李成全
何彦兵
廖伟
官红
姚舜
王文
张超平
邓天安
FU Hao;LI Chengquan;HE Yanbing;LIAO Wei;GUAN Hong;YAO Shun;WANG Wen;ZHANG Chaoping;DENG Tianan(Development Department of PetroChina Southwest Oil and Gasfield Company,Chengdu,Sichuan 610056,China;Downhole Operation Company of CNPC Chuanqing Drilling Engineering Co.,Ltd.,Suining,Sichuan 629000,China)
出处
《钻采工艺》
CAS
北大核心
2023年第2期35-40,共6页
Drilling & Production Technology
基金
国家自然科学基金“干热岩型地热泡沫钻井流体相变行为下井筒温度压力响应特性研究”(编号:52174008)。
关键词
环空憋压
憋压值
分段逐级憋压
固井质量检测
annulus pressure holding
pressure holding value
stage-by-stage holding pressure
cementing quality inspection
作者简介
符豪(1968-),工程师,1997年毕业于西南石油大学钻井工程专业,从事油气井钻井工程研究。地址:(610066)四川省成都市锦江区下沙河铺街59号联合广场,电话:13880189233,E-mail:fu_hao@petrochina.com.cn。
