高温深层碳酸盐岩裸眼酸压完井封隔器研制与现场试验

The Development and Field Testing of a High-Temperature Deep-Layer Open Hole Packer for Acid Fracturing Completion in Deep Carbonate Reservoirs

针对塔北深层奥陶系油藏裸眼完井过程中封隔器胶筒易老化、骨架易破损的问题,进行了故障原因分析,设计了柔性锚瓦结构,以保护钢骨架,防止大扩张比、高承压状态下钢骨架变形过大造成的胶筒破坏;在保持氟橡胶(FKM)优异耐老化性能的基础上进行了改性,提高其塑性和热稳定性,使其更容易在模具中注胶和成型;坐封机构进液通道设计了可投球激活的保护滑套,可以避免钻井液沉淀堵塞。改进后的裸眼封隔器耐温达180℃,封隔能力强,适用于不规则裸眼地层的长期密封。塔北哈拉哈塘作业区4口井应用了改进后的裸眼完井封隔器,封隔器下入顺利,坐封显示明显,大规模酸压施工及求产过程中套压无异常。研究结果表明,改进后的封隔器满足完井-酸压-求产一体化工艺需求,解决了塔里木盆地深层油气开发存在的问题,具有较好的推广应用价值。

Premature aging of packer rubber elements and damage-prone of packer skeletons during the open hole well completions have been a problem in the deep Ordovician reservoirs of Northern Tarim Basin.To solve this,the causes of failures have been analyzed,after which a flexible anchor slip structure was designed for the protection of steel skeleton and prevention of damage to the rubber element caused by the excessive deformation of steel skeleton under large expansion ratio and high pressure.While maintaining the excellent aging resistance of fluororubber,plasticizing modification technology was used to improve its plasticity and thermal stability,which would make it easier to be moulded through mold injection.For the fluid inlet channel of the setting mechanism,a ball-activated protective sliding sleeve was designed to avoid the settling and clogging of drilling fluid.The improved open hole packer had a temperature resistance of 180℃and strong sealing capacity,which was suitable for long-term sealing of irregular open hole formations.When applying such improved open hole completion packer in 4 wells in the Halahatang Area of Northern Tarim Basin,the RIH was smooth,the setting sign was obvious,and there was no abnormal casing pressure during the large-scale acid fracturing and production process.Research results showed that the improved packer met the needs of the integration of completion,acid fracturing and production testing,solved problems of deep oil and gas development in Tarim Basin,and had a good value for popularization and application.