Bay of Campeche, Mexico
In order to remove the requirement for a survey support vessel live “as-built” data during trenching was essential. Positioning algorithms were employed to allow extended layback ROV operations whilst auto processing techniques allowed DoB calculation, based on pre-trench pipe position.
While working with a client in the Gulf of Mexico, Sulmara Subsea was able to improve the speed of delivery of “as-trenched” survey work, as well as reducing overall vessel time spent, by performing simultaneous trenching and survey operations. The survey team on board identified that the vessel configuration would allow the ROV to fly behind the jet trencher, at a suitable offset, to allow trenching and the “as-trenched” survey to be completed in a single pass. This not only negated the need for a separate survey pass, but also enabled the project engineers and trenching supervisors to access data relating to the performance of the trencher in (almost) real-time, thus facilitating effective decision making and fostering confidence in trencher performance.
The overall project duration was reduced by approximately 25%. The client was impressed with the correlation between the simops survey DoB and conventional “as-trenched” survey results. Further confidence in the system came from continually comparing numerous passes on different pipelines before dropping traditional methodology in favour of innovation.