Deepwater environment pose several challenges and constraints on well drilling operations. These challenges include but are not limited to harsh and hostile weather conditions, distance from shore, water depth, personnel safety and piracy in some cases. All these can be successfully managed and operational excellence achieved through innovative approaches.
The aforementioned challenges, if not recognized and adequately addressed especially during the well planning phase, will ultimately manifest as unscheduled downtime, high-risk exposure, low operational performance and above all, increase in overall well cost. Petrobras and her partners recognized these challenges during the planning phase of a recent exploration well and put measures to optimize the operational efficiency of the well.
The exploration well is located in deepwater ALPHA block offshore outer continental shelf waters of Nigeria; western flank of the Niger Delta. The acreage spans 853.5 km2. The water depth range from 1600m to 1800m and an approximate round-trip sailing time of 60hrs (about 350 nautical miles) from the logistics base. Round-trip flight time of 1 hour (about 80km) from the nearest airport. Thus, the environment is considered remote with high level of logistics challenges.
This paper presents some of the innovative approaches employed in managing the challenges which led to the positive results achieved. It is imperative to note that our intent is to share our experiences and lessons learned in this well operation with the industry so that drilling operational process can be improved and well cost reduced significantly.