Flexible Pipelines Risk Based Integrity Management Planning

Abstract

Abstract This paper shares on recent effort in PETRONAS on standardization of risk model and risk-based integrity management planning for its flexible pipeline assets. A semi quantitative approach is adopted in determining the likelihood of failure by using set of descriptors, coupled with the company standard consequence of failure descriptors to define risk of each threat and damage mechanisms. Screening of credible threats involves understanding on the function and impact of each to flexible pipelines components and compared against failure statistics and experiences in industry. Then, a guideline on the Integrity Management Plan (IMP) was established based on the risk rating i.e. High, Medium and Low, underlining respective inspection, monitoring and maintenance activities required to reduce and control the risk to As Low As Reasonable Practicable (ALARP). The result of this standardization effort on the risk model for flexible pipelines, the company easily can determine its flexible pipeline risk timely. Meanwhile, with the IMP would enable the company to strategize and prioritize its resources to focus particularly to its high risk, thus high consequences flexible pipeline assets. In previous practice, each pipeline will be assessed based on engineering judgement through an exercise participated by various experts. While sometimes these criteria are not standardized from one pipeline to another, this exercise normally would take several days and sessions to complete due to the fact of lengthy review and challenge session to arrive to consensus on the final risk and its integrity management plan of each of its pipeline. Flexible pipelines integrity management is still considered new to the industry. This type of asset, originally installed on marginal fields with short lived economic life with very less or no maintenance at all. Nevertheless, most of these assets also have been operated beyond its design life as operators are continuously cutting down its production cost. Due to this, a robust integrity management system is required. It is imperative that with understanding on risk as well as exploring ways to maintain this kind of asset is becoming increasingly vital to balance between the risk of failure and cost to operate.