FSC were engaged to develop a Risk Based Inspection (RBI) regime for the hull structure of an ageing FPSO operating in Australia under a standard Class periodical inspection regime.
Such standard Class inspection schemes are designed to suit a range of vessels within a generic vessel class and consist of prescriptive inspection scope and frequency, based on the trends of the type of vessel under generalised conditions. An RBI approach however is asset specific with inspection scope and frequency tailored to specific asset risks under specific conditions.
Given the age and particular operating conditions of the asset, the standard prescriptive Class approach whilst robust and able to ensure structural integrity, lead to a sub-optimal inspection regime which was hard to implement offshore. It also resulted in unnecessary operations disruptions, higher costs and additional personnel safety exposure due to the extent of some manned inspections.
FSC therefore developed a tailored Risk Based Inspection regime for the asset in accordance with LR guidelines. This included a detailed basis of design to collate historical data and identify any knowledge gaps. Additional analysis was carried out, the results of which as well as inputs from key stakeholders during the RBI workshops, formed the key inputs to the qualitative risk assessment. Using the operator’s corporate risk matrix, defined inspection and monitoring methods and inspection frequency tables, suitable inspection and monitoring scopes and frequencies were determined to mitigate identified risks to an acceptable level whilst working within operational constraints.
The resulting Class approved RBI plan provided the operator and Class with a far better understanding of the specific risks applicable to the asset. This understanding was founded on an extensive and clearly documented evidence base, enabling tailored inspection scopes and frequencies to be implemented, increasing asset availability, and significantly reducing risk and cost.
RBI Plan Development