B-annulus pressure of in excess of 400 bar (5800 psi) was observed at the well head and because of concerns that an internal blowout could occur, it was necessary to abandon the Z -17 well. As only a single barrier was in place between the pressurized B annulus and the environment, the well integrity situation, which required constant monitoring, and regular bleed off posed considerable challenges to operations and risk to personnel. There was also the risk that a surface blowout could occur, if B annulus pressure managed to communicate
with the C annulus, and as such the C-annulus required continuous monitoring.
Petroleum Technology Company successfully reinstated dual barriers against the accidental release of annulus pressure, while facilitating the remote bleed off of annulus pressure from Petroleum Development Oman’s Z-17 well.