储气库SAB-4永久式封隔器套铣打捞实践

Milling and fishing of SAB-4 permanent packer in gas storage

贝克SAB-4封隔器是储气库完井中常用的永久式封隔器,其卡封性能可靠,得以广泛应用。但该封隔器回收过程相对复杂,不能像常规封隔器一样解封回收,尤其在储气库高压注采条件下,施工风险较大。通过对SAB-4封隔器结构和工作原理进行分析,制定了磨铣、套铣、打捞相结合的回收方案,成功完成了2口井的SAB-4封隔器及下部联座射孔管柱的回收施工,为储气库井更换注采管柱以及确保储气库井安全提供了一套行之有效的修井方法。

Baker SAB -4 packer is a common kind of permanent packer used in gas storage wells completion. It is widely used because of its outstanding sealing performance. But its withdrawal is complicated because it can＇ t be taken back by deblocking like other usual packers. The construction risks are especially high under high injection - production pressures of gas storage. By analyzing structure and working principles of SAB - 4 packer, a withdrawal project involving milling,washover and fishing was proposed to complete the withdrawal of packer and perforation pipes. Withdrawal con- structions for two wells were successfully implemented. A set of effective well workover method was provided for changing injection -production pipes in gas storage wells and guaranteeing safety.