Pre-job diagnostics indicated a tubing leak in a Gulf of Mexico well. Prior to the Seal-Tite® operation, a spinner survey was performed. Based on the survey, it was determined that the leak was near the packer. The Seal-Tite® pressure-activated sealant was delivered to just above the packer by a dump bailer. Pressure was released from the casing and the shut-in tubing pressure was maintained at approximately 5000 psi. A differential pressure was created from the tubing to the casing annulus and the sealant was carried through the leak path. The above process was repeated six times with six separate dump bailing operations. With each operation, the casing pressure was reduced until it reached zero pressure.
BP was experiencing a packer leak of almost a barrel per minute. The first Seal-Tite® operation was to use only Seal-Tite® sealant to cure the leak, but was unsuccessful due to the severity of the leak. During the second operation, cement was circulated through the leak. As expected, gas bubbling through the cement created micro-channels and only a partial seal was established. Both oil- and water-based Seal-Tite® sealants were then displaced below the packer without success. Finally, a weighted, water-based sealant was pumped down the annulus and through the micro-channels in the cement. As the sealant was pumped through the micro-channels, the differential pressure through the micro-channels caused the liquid sealant to polymerize into a flexible solid that closed off the leak paths through the cement. The packer leak was sealed and the casing pressure was eliminated.
A Gulf of Mexico well was experiencing leaks through the polished bore receptacle at a depth of approximately 14,100´. A Seal-Tite® engineer ran troubleshooting diagnostics and verified the communication leak through a polished bore receptacle. Seal-Tite® pumped an 18 Bbl HEC pill, followed by a 2 Bbl Seal-Tite® sealant pill, followed by 9.0# NaBr mixture. The Seal-Tite® engineer maintained pressure across leak site until the sealant pill crossed the leak site. As the leak sealed, a slight pressure increase was observed and the pumping was stopped. The engineer bled off the casing pressure, shut-in the casing and monitored the pressure. There was no pressure increase on the casing, indicating that the leak was sealed.