Offshore Integrity Management 20 years On - An Overview of Lessons Learnt Post Piper Alpha

Abstract

Abstract Since the piper Alpha disaster in 1988, many changes have been implemented across world offshore regions. The emanating points for these sweeping changes have been the Cullen Report and the UK North Sea industry. However, there are many secondary, finer points that constitute important lessons learnt, many of which still need to be addressed, if pragmatic life cycle safety and performance are to be recognized. This review looks at such major changes instigated by step changes in safety criticality regarding offshore assets. It is argued that the second tier modes of failure, such as internal corrosion, environmental cracking, erosion, etc., have been somewhat overlooked. These mechanisms are equally major threats to the integrity of any infrastructure, especially within high-risk deepwater and arctic applications. It is noted that such root causes of failure as witnessed in practice or as predicted in theory have yet to be appraised fully, and as a result such frontier areas may be sitting on the proverbial time bomb if due attention is not fully paid. The authors use wide experiences post Piper Alpha to highlight worries and concerns, offering rational pragmatic solutions through related case histories. Conclusions and recommendations are based on cross-asset interpretations and verified, with solutions offered. The clear industry disconnects between knowledge transfer and management under this tutelage are identified, and refocused. Powerful advances in mechanical, materials, and corrosion engineering are emphasized and the use of key performance indicators (KPIs) is reasoned for best life-cycle integrity management. This is important where surprise failures, environmental and political snafus are not an option. It is argued that more purposeful design investment at CAPEX is more amenable than at OPEX, and the gray zone between the two cost centers must be bridged to industry advantage. Introduction On the 6th of July 1988, the world's worst offshore oil industry disaster occurred on the Piper Alpha platform in the UK sector of the North Sea. The loss of life was staggering: 167 dead, with 62 survivors, and dozens badly injured. Wood Group itself lost 39 employees in that tragedy. Much has been written and debated on the incident. This paper examines a new angle on the subject matter, and that is the closer review of so called secondary items of interest. These are corrosion-related items that have been accepted as pertinent over the years, but generally and often erroneously perceived with less priority. This is largely because the subject matter is considered too specialistic, or complex and often requiring costly subject matter expertise. As a result, corrosion integrity is sometimes erroneously and dangerously taken off the agenda by non-subject-appreciative project or even industry leaders. This paper delves into this sometimes contentious area, examines the role of corrosion mechanisms in the root cause analyses of most significant failures and virtually all loss of performance issues. The interpretations are made with the support of solid observations and new understandings in the direct context of integrity and corrosion management. The authors come from a mixed blend of offshore disciplines, with over 80 years of combined experience, predominantly from the North Sea and Gulf of Mexico. The objectives are aimed to be educational and not controversial, but the opinions are strong and considered very worthy of continued debate and development.