Innovative inspection techniques for ultra deepwater drillships and other floating O&G production assets saving costs, enhancing safety, while assuring operational availability and asset integrity

Abstract

The Hull Inspection Techniques and Strategy (HITS) Joint Industry Project (JIP), a subgroup of the Floating Production Storage and Offloading (FPSO) Research Forum, called for new methods to be developed that enhance safety, reduce costs and support the assurance of integrated asset management. Hull integrity is critical to enhancing safety and operational effectiveness for production operations, particularly for high-value assets. Good hull integrity requires accurate, relevant hull-inspection data of the internal structure, isolation valves, moonpools, external appendages and positioning systems. Current methods use divers or remotely operated vehicles (ROVs); this often disrupts drilling operations and, in the case of divers, is a high but managed risk. HITS JIP called for methods to minimise diver and man intervention in confined spaces. This has now been achieved on several assets while on station, operational and on-hire by an innovative method of conducting inspections from within the hull and using advanced techniques to inspect critical isolation valves, moonpool high-stress areas, thrusters and hull appendages. Aligning internal and external structural inspections optimises operational availability further and is achieved by means of class-approved ‘long-term inspection plans’ that align the ‘underwater’ scope with other hull inspections and spreads the work over several 5-year cycles. As well as safety enhancements, benefits include over 70% persons on board (POB) reduction on diver under water inspection in lieu of drydocking (UWILD) operations, minimising downtime and operational impact, and high-value inspection data. Further advances in hull inspection have also been proven that eliminate man entry of confined spaces for inspection of ballast and other tanks.