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There are more than 6,700 platforms in operation worldwide and 30% of them have been in operation for more than 20 years. Many of these platforms are operating beyond their original design life. As more oil and gas discoveries have been made operators have been required to extend the life of their offshore assets without compromising personnel safety or the integrity, reliability and productivity of these assets.Demonstration of structural integrity of mature assets particularly those reaching or exceeding their design life is of paramount importance when considering life extension. The risks that are commonly posed by life extension are:• Corrosion -harsh corrosive environments • Overload -wave action, additional topside and environmental loads • Operational changes -platform modifications • Incidents -ship collision, explosion • FatigueManaging the structural integrity of offshore assets is one of the most challenging tasks imposed by a life extension project. This includes industry wide consultations, to deploy new technologies such as online monitoring systems. Life extension of an offshore installation is necessitated for a variety of reasons and results in some possible changes. Changes to a platform require re-assessment of the structure to evaluate increase in environmental loading and fatigue damage on the substructure as well as to account for variation in topsides weight.

To mitigate the threat of corrosion in any hydrocarbon pipeline a pipeline corrosion management strategy (CMS) is required. Once this Pipeline CMS is implemented its performance should be monitored and assessed on a regular basis to maintain and improve pipeline integrity. Corrosion key performance indicators (KPIs) are a powerful tool and should be used for this purpose. This article provides a detailed account on how corrosion KPIs are selected, expressed and what their main benefits are for hydrocarbon pipelines.

As offshore assets age they become more susceptible to hydrocarbon leaks and failures due to corrosion issues. Thus, they pose a greater threat progressively to the personnel's health and safety and also to the protection of the surrounding environment. An efficient way to reverse this trend is to create and implement an asset corrosion management strategy (asset CMS) which would simultaneously improve asset integrity and enhance plant uptime through reducing the number and severity of hydrocarbon leaks (due to corrosion), hence improving both personnel safety and environmental protection. Such an asset CMS would improve HS&E compliance (in particular in regard to the HSE's KP3 Report and its findings) onboard an offshore asset through pre-empting sections of the process systems before they can develop into a failure due to corrosion. This paper contains real data collected over a five-year period illustrating how the above has been achieved for an offshore asset in the North Sea through reducing the number and severity of hydrocarbon leaks over time, thus improving personnel safety and environment protection in particular and making the asset more HS&E compliant in general. Introduction Corrosion management enhances the value of an aging asset by maintaining or improving its production rate and continuity and by reducing its overall integrity management costs. To help discussing the above subject a range of data collated over a five-year period and pertaining to an offshore platform have been used. Such data render possible the comparison of five parameters before an after the implementation of a new asset corrosion management system (asset CMS). The paper also discusses how having a real risk-based inspection (RBI) system could help identifying high corrosion rate areas earlier; so a remedial action is planned for before they can develop into a corrosion failure forcing a total or partial operations shutdown upon the asset. Such data also illustrate that by using a real RBI system the extent of UT inspections can be optimised, while simultaneously more critical areas can be identified and the relative inspection costs significantly reduced. Corrosion Management Definition and Scope CM for any asset may be defined as the process of reviewing the applied corrosion engineering (CE) considerations, the regular monitoring of their performance and the assessment of their effectiveness post-commissioning. Therefore CM and its applications are very closely associated with an asset's operations phase. 1 Despite the existing distinctions, many of us still regard CM as a synonym for corrosion engineering (CE) with identical set of applications. For more detailed information on CM, its structure, principles and applications please refer elsewhere.2 Benefits of Corrosion Management Applications As an asset ages it becomes more susceptible to having more frequent unplanned operations shutdowns due to corrosion issues caused mainly by either or both of the following:The continuous thinning and the eventual exhaustion of the corrosion allowance layerCorrosion issues such as MIC getting more acute resulting in higher corrosion rates