压差激活密封剂

针对油气井的管件在生产过程中易出现损坏泄露,优选了胶乳、激活剂、终止剂、稳定剂,复配出一种模拟人体创伤流血自身修复的压差激活密封剂。该密封剂的主剂为丁腈胶乳,激活剂为CH3COONa、Mg SO4和Na Cl,终止剂为Gemini1231及Gemini1631,稳定剂为钠基膨润土。研究表明,该密封剂只在出现压差的泄漏点凝固,在其他情况下保持流动状态;使用温度为–20~120℃;密封剂粒度在0~1 000μm范围可控,甚至更大。采用φ139.7 mm油管对丝扣进行破坏模拟泄漏,结果显示,泄露速度为600 m L/min时,采用压差激活密封剂停留60 s成功修复,修复后体系在水压为40 MPa和氮气压力为35 MPa时的密封效果符合行业标准。

Pressure Activated Sealant

A pressure activated sealant was developed to overcome leaking of oil well pipework. The sealant was formulated with butyronitrile latex as base additive, CH3COONa, MgSO4 and NaCl as activators, Gemini1231 and Gemini1631 as terminators and sodium montmorillonite as stabilizer. Laboratory study showed that this sealant only became coagulated at leaking sites where there were differential pressures, otherwise maintained in mobile state. The sealant worked at temperatures between -20℃ and 120℃ and had particle sizes between 0 μm and 1,000 μm, or bigger. In a simulation test with 139.7 mm tubing in which the thread was damaged, when leaking rate was 600 mL/min, the leaking was stopped after applying the sealant and waiting for 60 s. After reparation, no leaking was found for the tubing under 40 MPa of water pressure and 35 MPa of nitrogen gas pressure, satisfying the requirement of industrial standard.