This paper highlights PETRONAS's journey and experience in the Underbalanced Drilling (UBD) fractured basement pilot project, a 2 wells campaign in the Malay Basin. An integrated UBD team, has set best in class performance, applying lessons learnt in the 1st well to the 2nd well. Major highlights are the key learnings implemented, challenges turned to opportunities, overall project management, well delivery process, well assurance safety processes, achievements and future enhancements for UBD operation.
The process started with a comprehensive UBD Fractured Basement Pilot Project Feasibility study, assisted by risks assessment process which turned into a full engineering and execution plan. Well planning, well constructions and execution of this project will be highlighted. Relevant operational excellence process in PETRONAS such as DWOP, AAR, HAZID, and HAZOP has contributed to excellence in HSE and well delivery performance. Internal assurance process including Wells Peer Review and COP has facilitated a safe and successful project delivery. A multidiscipline and integrated wider scale project execution successfully yielded a noticeable performance improvement in the 2nd well in comparison to the 1st well.
For a back to back UBD well, the key learnings have been immediately brought forward and implemented in the 2nd UBD well. Results were apparent and can be demonstrated by the well KPI performance and benchmarking against other operators in Malaysia within the same class. This UBD pilot project demonstrated the project feasibility to drill a challenging fractured basement using UBD technique, which can be further enhanced and replicated to a similarly suitable projects. Overall, the 2nd well was completed 27 days ahead the planned days, with significant cost saving and total NPT of only 4.72%; while managing to drill with additional scope as requested by subsurface.
This campaign provided a basic foundation to institutionalize UBD capability and also will open up a new chapter in PETRONAS's involvement in the whole process starting from well planning & engineering, well construction, and post mortem for UBD specific projects in the future. This template will be used, replicated and improvised to suit future UBD drilling campaign particularly in PETRONAS' operations. In line with the dynamism of this Company, and frequent approach for creative & non-conventional technology implementation, it has kept PETRONAS abreast with a niche and most advanced industrial practices for a better & more effective natural resources exploration supporting the ability to maintain the supply of global non-renewable energy demand.