Abstract
As part of the old time reservoir strategy to develop the Cusiana field in Colombia, PosiSet Plugs were set on Electric Line with cement on top mainly for Gas Shut Off purposes. In the recent years, it was necessary to remove the isolation to comply with the updated reservoir strategy to produce the lower reservoirs. Instead of a Workover rig intervention for cost optimization, Coiled Tubing was used to mill the cement, mill and push the PosiSet Plug and reestablish access and production of previously isolated zones.
At the beginning there were not many case stories of PosiSet Plug milling worldwide and several difficulties were observed in the first attempts. Milling time was high and not all interventions were successful. However a robust learning curve was created allowing the current removal of PosiSet Plugs without major difficulty in terms of hours. Tools used and operational procedure represents the key points of the implemented strategy.
