Meeting the demand for barrier plug integrity assurance & verification of well abandonment barriers. SPE 182468 By Arild Stein, Interwell, 13 Oct 2016

Well barrier installation practice is dictated by territory specific regulations which are largely based on historic practices. However, emerging technologies, tightening regulations, and demands from asset owners are gradually affecting the way we carry out installations.

Driving the technology development is cost savings, the need for documented verifications on temporary barriers, and barriers installed for well suspension and future P&A barrier installations.

There are multiple issues involved in gaining proper verification of an installed barrier e.g. two wellbore barriers installed in close proximity, wells general ability to support an inflow test, and time it takes to get a segregating well stable.

The wireless Barrier Verification System (BVS) was developed to meet the demand for barrier plug integrity assurance. The system consists of a pressure sensor with a transmitter attached below the barrier plug and a Receiver is mounted on top of the installation tool to wirelessly record the pressure measurements below the plug. An additional pressure sensor forms part of the receiver to provide an accurate pressure measurement above the plug.

The transmitter sends pressure readings and can record for multiple days depending on battery selection, wellbore temperature and logging frequency. The Receiver also records and stores the pressure information collected above and wirelessly below the barrier plug.

The measured pressure/drawdown testing from the BVS together with the forces and travel distances from the installation profile, recorded by the EST (Electronic Setting Tool), gives valuable information to determine the overall quality of the barrier installation.

The wireless BVS system was first used in the NCS, mounted on a 5.5” Medium Expansion (ME). Following the setting of the barrier plug, it was pressure tested from above. The results showed a clear differential pressure across the barrier plug which verifies and provided assurance that the plug was holding pressure.