Going Deeper: Inspecting Subsea Live Assets by Means of an Advanced AUV Solution

Abstract

Abstract Data has always been the key: more data, at higher frequency, with better quality and, possibly, always cheaper. Data, if properly handled, means knowledge and knowledge allows better performance and with less risk. In this context, offshore IMR is not different compared to other business segments, with the addition that, in 2023, it appears to be somehow obsolete the need to mobilize a diesel propelled vessel with circa 60 people onboard with the purpose of taking some pictures and videos of subsea facilities. In order to respond to this challenge, several players in the market have launched their development programs, with the objective of developing and qualifying a new generation of subsea vehicles, or better drones, capable to match the industry needs in terms of cost efficiency and environmental footprint as well. Focusing on pipeline inspections, AUVs are the preferred choice for long range activities while optimizing the need for support vessels in constant control of the subsea operations. However, the complexity of the subsea domain resides in the non-linear objects such as subsea XTs, manifolds, etc., i.e. all those subsea assets requiring detailed inspections at frequent interval mainly to assess the status of valves, cathodic protection, flanges and connections in general. Doing this with a standard AUV is fairly impossible, therefore a new generation of advanced AUV solutions is required, capable of DP and hovering modes, thus adding the flexibility to stop-by at given location and perform a detailed assessment of the target point, including search and localization of possible hydrocarbon leaks. This functionality implies a rethinking of the subsea vehicle which -as anticipated- is then commonly redefined by the offshore industry as "subsea drone". After extensive qualification programs such subsea drones are currently being introduced by different suppliers and service providers to the market, promising substantial achievements in terms of inspection effectiveness. The focus of this paper shall then be in sharing the direct experience made by Saipem while bringing FlatFish to deepwater, in what it is believed to be a unique subsea campaign setting a number of industry firsts: autonomous deepwater inspections of flowlines, XTs, structures and risers. Such deepwater operations, carried out offshore Brazil at the beginning of 2023, have been an essential achievement in the subsea drone development and qualification plan, unlocking the next stage of FlatFish continuous development while marking a milestone for the offshore energy industry. Saipem intends to share, from its privileged viewpoint, the main outcomes and lessons learnt from such deepwater pilot operations.