BHP Pyrenees WA-12-R Drilling Campaign
Location: Exmouth Sub-basin, Western Australia
Objective: Consult in the investigation of a mooring line entanglement with subsea assets during a rig move conducted by another contractor. Identify barriers to prevent similar incidents in the future and support rig moves going forward.
Solution: Delmar recreated the incident through simulation and provided a subsea view of the ensuing contact between the mooring system and the subsea assets. Subsequently, Delmar developed the Del-3DM software package to provide a rig move simulation tool to train, assess competency, and vet mooring plans for future rig moves.
Summary: Delmar Systems, Inc. was contracted by BHP to join the incident investigation team tasked with identifying the root cause of the incident. We were also contracted to identify additional barriers to implementation so as to prevent similar incidents in the future.
Delmar developed a new software package at the operator’s request and provided training/competency assessment sessions with the rig movers prior to the subsequent jobs. Delmar provided real-time offshore 3D monitoring services on the remaining rig moves for the campaign.
More Detailed Scope of Work:
Delmar Systems, Inc. was contracted by BHP to join the incident investigation team tasked with identifying the root cause, and identifying additional barriers to implementation, preventing similar incidents in the future.
Using advanced numerical analysis techniques, Delmar created a video of the mooring line profiles relative to the subsea infrastructure using the historical GPS rig position data along with the rig winch tension and payout records spanning the time period of the incident. The generated video clearly demonstrated the causal factors of the incident.
Through further analysis of the developed video, many process control issues were identified. Delmar recommended several additional barriers to prevent similar incidents in the future. Delmar supported the remaining mooring recovery offshore ensuring that no additional damage occurred.
Del-3DM is now used prior to rig moves to simulate the various proposed steps of the installation and recovery procedures. Kedging or winching of the rig from safe zone to safe zone can be simulated and competency assessed through an interactive session.
BHP now uses Starfix.moor, in conjunction with Del-3DM, to provide real-time monitoring of the mooring chain catenaries relative to the subsea assets for all rig moves in and around subsea infrastructure. These tools allow the rig movers to visually see the mooring line profiles relative to the subsea infrastructure based on the current surveyed rig position and the observed mooring line lengths and tensions.
Instituting the additional barriers and adhering to the defined process controls put in place, Delmar has completed many subsequent mooring deployments and recovery operations for multiple drilling rigs in and around the Pyrenees field without issue.