伊拉克南部油田φ244.5 mm套管环空带压补救技术  

Remedy of Sustained Casing Pressure inφ244.5 mm Casing Annulus in South Oilfield of Iraq

作　　者：王翔宇 刘文明 林志辉 刘金鹏 李文文 桑明 李中国 WANG Xiangyu;LIU Wenming;LIN Zhihui;LIU Jinpeng;LI Wenwen;SANG ming;LI Zhongguo(No.2 Cementing Branch Bohai Drilling Engineering Companty,Ltd.,Tianjin 300280)

机构地区：[1]渤海钻探工程有限公司第二固井分公司,天津300280

出　　处：《钻井液与完井液》2021年第3期360-364,共5页Drilling Fluid & Completion Fluid

基　　金：渤海钻探重大研发项目“环氧树脂修井液及核心外加剂开发研究”(2020ZD07F-01)。

摘　　要：伊拉克南部哈法亚、米桑等油田存在异常高压盐膏地层,部分井固井后环空带压(0.69-17.24 MPa),严重影响后期开发,针对上述问题,优选可固化环氧树脂进行封堵作业。评价了环氧树脂稠化时间、抗压强度、流变等综合性能,实验结果表明:通过调整固化剂加量,环氧树脂工作液稠化时间在100-500 min范围内可调,48 h抗压强度大于50 MPa,流性指数大于0.94,稠度系数小于0.10 Pa·sn。现场采用阶梯式挤注环氧树脂进行封堵作业,挤入量达到100 L以上,现场实施3井次,72 h后井口压力降低为零,成功解决伊拉克南部油田高压盐膏层φ244.5 mm技术套管环空带压问题,对环空带压井治理具有一定借鉴作用。Sustained casing pressure was encountered when cementing the wells penetrating abnormally high-pressure salt/gypsum formations in the Halfaya Oilfield and the Missan Oilfield in the south of Iraq.The sustained casing pressure was in a range of 0.69–17.24 MPa,seriously affecting the later development of the oilfields.A curable epoxy resin was used to solve this problem.Laboratory test was conducted to evaluate the thickening time,compressive strength and rheology of the epoxy resin fluid.The test results showed that by changing the concentration of the solidifying agent in the epoxy resin fluid,the thickening time of the epoxy resin fluid can be adjusted between 100 min and 500 min,the 48-hour compressive strength of the epoxy resin fluid can be greater than 50 MPa,the flow index of the epoxy resin is greater than 0.94,and the consistency coefficient is less than 0.10 Pa·sn.In field operation,the epoxy resin was squeezed and injected stepwise into the well and plug it.The total volume of epoxy resin fluid used was more than 100 L and the plugging operation with epoxy resin was done for three times in three wells.After 72 hours of squeezing the epoxy resin,the wellhead pressure was reduced to zero.Using this method,the sustained casing pressure in theφ244.5 mm casing annulus encountered in the south oilfields of Iraq was successfully solved.This technology can be used to solve similar sustained casing pressure problem.

关 键 词：高压盐膏层 环空带压 环氧树脂 阶梯式挤注 

分 类 号：TE256.6[石油与天然气工程—油气井工程]