Title : Magnetic Tomographic Tnspection (MTI) based fitness for service assessment
Abstract:
This paper shares on recent effort in PETRONAS on standardization of risk model and Risk-Based Inspection (RBI) and Integrity Management Planning (IMP) for its flexible risers and pipelines asset. A semi quantitative approach is currently adopted by PETRONAS 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. These were developed in-house by engineers and technical specialists which then used as a guideline to further establish an Integrity Management Plan (IMP) 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 on the risk model for flexible risers and pipelines aids PETRONAS to understand and determine its flexible and risers pipeline risk timely for intervention to prevent their failure. 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. Meanwhile, flexible risers and pipelines Risk-Based Inspection (RBI) is still considered new to the industry as the current practice is following a time-based approach defined by the manufacturer. 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 by reducing capital expenditure of these assets. Thus, a robust integrity management system is deemed necessary. 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 premature pipelines failure and production and operational cost.
Audience Takeaway Notes:
- Understanding of a systematic and standardized approach of categorizing risk as well as identifying integrity management plan for flexible pipelines developed and implemented by PETRONAS
- Helps audience to adopt similar approach or to develop site specific Risk Based Integrity Management Planning for flexible pipelines
- Open for possible exchange of ideas and collaboration with others flexible pipeline operators to establish a standard approach for Flexible Pipelines RBI for inspection and maintenance optimization.
