Integrity eXplorer Service Evaluated Cement Despite Microannulus in Casing Overlap Section
An operator in the Caspian region needed to evaluate 13,120-ft (4000 m) of cement behind a 7-in. liner within a 95/8-in. casing. Cement quality was especially critical in this well due to the complex lithology and irregular depletion of formations. The operator was concerned that cross-flow between permeable zones could create well integrity issues. Temperature logs and a conventional cement bond log were acquired soon after the cement job to determine the top of cement. But after performing a pressure test of the casing, the operator suspected there was a microannulus between the cement and casing and committed to investigate further to confirm zonal isolation. Microannuli are interpreted as bad cement-to-casing bond on cement bond logs. This causes operators to spend a great deal of time and money trying to remediate their cement.
Baker Hughes, a GE company (BHGE), recommended concurrently deploying the Integrity eXplorer™ cement evaluation service and Segmented Bond Tool™ (SBT™) services in order to evaluate the cement using three independent acoustic measurements: shear wave and flexural wave from the Integrity eXplorer service and compressional wave from the SBT service.
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