摘要
为满足Halfaya油田泥岩段井壁稳定、高压盐膏层安全钻进和有效保护储层等要求,开展钻井液体系优选和性能评价实验,形成的有机盐钻井液流变性能良好,120℃高温高压失水11.6 mL,泥饼摩阻系数0.043 7,高密度下抗盐钙污染能力强,对（40 ～60）/（20 ～40）目砂床的滤失量均＜3 mL,泥岩滚动回收率＞90％、16 h线性膨胀率＜7％,岩心动态污染酸洗后渗透率恢复值＞90％、动失水＜4 mL.2011 ～2013年,该钻井液累计应用20口井,钻进泥岩过程中未出现频繁扩划眼、泥包钻头、遇卡等复杂,盐膏层高密度条件下流变性能稳定,有效抑制了膏盐蠕变缩径,完井测试显示酸洗前表皮＜1、酸洗后＜0,取得了良好的稳定井壁和保护储层效果,有效保障了钻井安全高效顺利实施,对实现该油田快速建产具有重要意义.
In order to meet the wellbore stability of shale stone,safety drilling of high pressure salt-gypsum formation and the effective reservoir protection for halfaya oilfield,the optimization of drilling fluid system and experimental evaluation of performance were conducted.The laboratory evaluation results showed that the organic salt drilling fluid system had good rheological performance and strong ability for salt-calcium pollution under the condition of high density.The system＇s HTHP loss was only 11.6 milliliters under the temperature of 120 centigrade,mud cake friction coefficient was 0.043 7,sand bed＇ s loss was less than 3 milliliters under the mesh size of forty to sixty and twenty to forty,mudstone＇ s rolling recovery was more than ninety percent and linear expansion rate was lower than 7％ in sixteen hours,the permeability recovery values of cores soaked with acid after damage experiments were all higher than 90％ and the dynamic filtration was less than 4 milliliters.Between 2011 and 2013 year,this drilling fluid applied in twenty wells of halfaya oil-field.In the processes of application,no frequent reaming,bit balling,sticking phenomenon existed.It had steady rheological properties under the condition of high pressure salt-gypsum formation with high density and effectively inhibited the salt and gypsum dissolution.The skin factor before acid-washing is less than one,and after acid-washing is less than zero.The organic salt drilling fluid revealed good borehole stability and reservoir protection effect.So this technology effectively ensured the smooth implementation of saftely drilling and played an important role in the fast productivity construction for halfaya oilfield.
出处
《科学技术与工程》
北大核心
2015年第1期38-41,共4页
Science Technology and Engineering
基金
中国石油海外勘探开发公司项目专题(HFY-E&D-2013-002)资助
关键词
钻井
有机盐钻井液
井壁稳定
保护储层
高压盐膏层
Halfaya油田
drilling
organic-salt drilling fluid
wellbore stability
reservoir protection
high pressure salt-gypsum formation
Halfaya oilfield
