套管外补接技术在水下井口的应用

Application of casing external patching technology in underwater wellhead

南海东部某区块采用水下井口开发,完井阶段对井筒完整性测试时,发现套管存在泄漏点;采用封隔体(RTTS)确认漏点位置,进一步采用高精度声波能谱成像(SNL)测井及井下电视确认浅层套管存在漏点;对比多种工艺方案,最终选择切割漏点以下套管,使用套管外补接技术回接套管,确保井筒完整性。利用外补接器使新套管与原井套管连为一体,同时不缩小原有井筒内径,保障后续工艺的实施,能够有效地解决水下井口浅层套管完整性问题。

Underwater wellhead development is adopted in a block in the east of the South China Sea,during wellbore integrity test at completion stage,leakage point of casing is found;Use RTTS to confirm the location of leakage point,further use SNL logging and downhole television to confirm the existence of leakage points in shallow casing;Compare various process schemes,finally,cut the casing below the leakage point,connect the casing back with the external casing patching technology to ensure the integrity of the wellboreThe new casing is connected with the original well casing by using the external connector,and the internal diameter of the original well bore is not reduced,so as to ensure the implementation of the follow-up process,which can effectively solve the integrity problem of the shallow casing at the underwater wellhead.