改进型低自由水钻井液在NP4-55井的应用  

Application on Innovative Low Free-water Drilling Fluid in Well NP4-55

作　　者：赵亚宁[1] 陈春来[1] 秦博[1] 卢淑芹[1] 李占伟[2] 

机构地区：[1]中国石油冀东油田钻采工艺研究院 [2]中国石油冀东油田勘探开发建设项目部

出　　处：《钻井液与完井液》2012年第5期30-32,36,共4页Drilling Fluid & Completion Fluid

摘　　要：NP4-55井是南堡4号构造的一口重点探井,该井东营组地层存在大段泥岩,水敏性强,易造成水化剥落;该区块低孔、低渗,储层水锁损害比较严重;受井斜影响,中深层井壁稳定性差;探井对钻井液荧光要求高,常规钻井液技术难以满足施工要求。通过室内优选和评价,该井三开使用封堵性、润滑性、抑制性、储层保护效果好的低荧光改进型低自由水钻井液,该钻井液较强的抑制性配合防水锁剂的使用,降低了储层的水敏和水锁损害,油层保护效果提高,渗透率恢复值可达100%;在钻进过程中岩屑棱角分明,回收率达90%以上,平均井径扩大率仅为4.19%,改进型低自由水钻井液在NP4-55井的成功应用,满足了南堡油田中深层低渗油藏勘探开发的需要。The Well NP4-55 is a key exploration well of Nanpu oilfield.Some difficulties are encountered in this well,such as a long section of mudstone in Dongying group that is strong water sensitivity,low porosity and permeability that the reservoir is easy damaged by water blocking,sloughing in middle to deep formations,and high requirements of fluoroscopic degree.In this paper,the low fluoroscopic degree innovative low free-water drilling fluid system is developed,and the application in the third interval shows that it has good performances of sealing,lubricity,inhibitory and reservoir protection.Moreover,the permeability recovery value is 100%,the cuttings recovery rate is more than 90%,and the average borehole diameter enlargement rate is only 4.19%.

关 键 词：改进型低自由水钻井液 探井 低渗储层 泥岩 井壁稳定 

分 类 号：TE254.3[石油与天然气工程—油气井工程]