T726井石炭系盐膏层钻井完井技术

T726井是中国石化西北分公司在塔河油田西南部边缘地区布置的一口重点评价井。针对塔里木盆地石炭系盐层埋藏深,温度高,地层压力大,极易发生“缩径、坍塌”,造成卡钻,同时由于盐岩层的塑性蠕动,形成不规则井眼,甚至造成套管挤毁变形事故,井身质量难以控制,固井质量难以保证等问题,通过对同类型已钻井进行总结分析,提出了一系列钻井技术措施,并在T726井严格实施。结果表明,施工全过程安全无事故,盐层套管无变形,井身质量和固井质量优良,为以后在该地区石炭系盐膏层安全钻井积累了成功的经验。

Drilling and Completion Technology in Carboniferous Salt Formation of Well-T726

Well-T726 is an important appraisal well,which is arranged in the south-west frontier area of Tahe oilfield by Northwest Exploration Bureau of SINOPEC.The characteristics of the salt formation in Tarim Basin is deep,high temperature and high pressure,easy to result in the undergauge,collapse,drill bit or pipe sticking.At the same time,the plastic creep of salt formation can cause borehole irregular,even lead to the troubles of casing collapse and casing deformation.It is very difficult to control the wellbore and cementing quality.In this paper,a series of drilling technical measures have been provided and applied in Well-T726 through analyzing the same type of wells early drilled.The result showed that no safety problems and no casing deformations occurred,and got a good wellbore and cementing quality in whole process of drilling operation,which accumulated the successful experience for future safety drilling in carboniferous salt formation in this area.