伊拉克鲁迈拉油田优化固井技术

Application of Optimized Cementing Technology in Rumaila Oil Field

摘要:

伊拉克鲁迈拉油田地层破裂压力低，技术套管固井易发生漏失，生产层页岩层发育导致井眼不规则，存在“大肚子”和井眼缩径、固井顶替效率低、固井质量难以保证的情况。为此在后期固井施工中，通过分析地层特性，从影响固井质量的几个关键因素出发，优化堵漏技术措施。利用固井设计软件，优化扶正器下放数量，通过室内试验优选抑制性加重钻井液，控制调节不稳定页岩层钻井液性能参数，将钻井液API失水量控制在4 mL、密度1.35 g/cm3，优化固井工艺措施，形成了一套适合该地区的综合固井技术。现场试验中，固井质量合格井段达到了80%以上，优于同区块其他队伍施工井段。

Abstract:

Because of low fracturing pressure in Rumaila formation, leakage is easy to happen in the intermediate casing cementing procedure; the shale development in production layer leads to irregular chambering and shrunk holes; cementing displacement efficiency is low and it is difficult to guarantee cementing quality. In late well cementing construction, the formation characteristics are analyzed starting from several key factors that affect the cementing quality to optimize the technical measures of plugging and by cementing design software to optimize the number of casing centralizer; through indoor test, inhibited weighted drilling fluid is optimized to control and adjust the performance parameters of drilling fluid used in unstable shale layer, the API fluid loss is controlled at 4mL and density 1.35g/cm3. A set of comprehensive cementing technology is formed, the cementing qualified ratio reaches to more than 80% in field tests.