Underbalanced drilling limitations - PetroWiki

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There are limitations, as well as advantages, to underbalanced drilling (UBD). Before embarking on a UBD program, the limitations of the process must be reviewed. There are technical limitations as well as safety and economic limitations to the UBD process. Wellbore stability is one of the main limitations of UBD. Borehole collapse as the result of rock stresses is one issue to consider.