Abstract

Total Indonesie started combining DST (Drill Stem Tests) with underbalanced TCP (Tubing Conveyed Perforation) in order to try to flow zones in delineation wells which were not flowing with classical wireline methods of perforation. The theoretical advantage of underbalanced TCP would be:

– Perforating with a well bore pressure lower than for mation pressure

– Having an immediate clean up of perforation and not having mud particles clog up perforations while drill stem test tools are being run in hole.

This paper will describe the DST assembly used prior to underbalanced TCP. It will then describe problems encountered using underbalanced TCP in the first series of tests leading to further modification of the DST assembly. Evolution of TCP themselves from "dropped bar" ignition to "pressure actuated" ignition will also be described, including the draw backs and advantages of each.

Finally the currently used DST assembly will be shown and illustrate further evaluation done to accomodate production logging tools.