The manufacturer of External casing packer for thermal recovery will explain the reasons and failure analysis for you.

Use of External casing packer for thermal recovery:
1. In drilling operations: as a type bridge plug or a recoverable type bridge plug, a working packer or a type cement retainer.
2. During the test operation: separate the test interval from the drilling fluid and other intervals.
3. In the cementing operation: as an out-of-pipe packer, it can avoid the upward channeling of formation fluid caused by drilling fluid channeling and micro-gap.
4. During perforating operations: keep the gas pressure.
Reasons for the stuck external casing packer for thermal recovery:
During the test, when the packer was unpacked, the hydraulic anchor could not return normally, resulting in the RTTS packer being stuck. The common reasons are roughly as follows:
1. Corrosion and deformation of casing: Under the long-term immersion of formation fluid and the extrusion of rock formation, the casing of the oil layer will usually deform or corrode to varying degrees. The tile pole may be deeply embedded in the casing wall and cannot be returned, causing difficulty in unsealing.
2. Sand stuck: The formation sand and the sand settling not caused by well flushing will accumulate on the upper part of the packer, so that the hydraulic anchor cannot be returned smoothly during unpacking, resulting in the packer being stuck.