PETRONAS embarked on a new challenge to drill and complete 5 wells with high bottom hole temperature (BHT) of 180°C and highly deviated fractured carbonate with high velocity gas producers. These wells utilized 7" big bore production tubing with new material 17CR instead of the expensive cold worked 22CR duplex stainless steel (DSS).
As the first application of 17CR production tubing material in the world, a lot of risks were taken into account and mitigated via various approaches from planning engineering stage until execution. These mitigation measures included the qualification of material and connection; operational details involving parties from different disciplines to ensure smooth and efficient deployment of 17CR tubing. In addition to that, optimization opportunities were explored to further increase running efficiency and reducing flat time while ensuring tubing integrity is intact.
The successful deployment of 17CR were attributed to the following:
Connection modification from JFE BEAR to JFE BEAR DR-PK to minimize the risk of galling around the metal-to-metal seal area on the newly developed 17CR CRA material
Tubing was racked back in double joints per stand offline during installation using offline activity cantilever (OAC) deck available on a tender assisted rig to improve running time
Utilization of side door elevator instead of single joint compensator to enable running tubing in double.
Usage of Flush Mounted Slip (FMS) dressed with pre-qualified low penetration dies, to ensure sufficient gripping on the 17CR tubing OD surface without being affected by the surface scale which is known to have with high hardness value
Usage of low penetration dies instead of non-marking type hydraulic tong to reduce tubular running cost
With the above mitigation measures put in place, the project was delivered with high efficiency in terms of tubular running speed achieving up to 14 joints per hour on 7" high alloy CRA tubing with extremely low number of rejection rate (0.3%) for the entire project. Utilization of 17CR as an alternative to 22CR DSS has also contributed direct cost saving of up to USD 8.2 mil to the project.