In the early 1990s asset integrity management was addressed by increasing inspection programmes. In the late 1990s, increasingly sophisticated IT tools were developed, and today a complex mix of strategies, IT solutions and inspections are often employed. This can potentially lead to client dissatisfaction, since from an operator’s point of view ‘it costs a lot, it’s complicated and we’re not sure we really need it’.
There are many different definitions of pipeline integrity management (PIM), including those listed within API 1160 and ASME B31.8S.
As a simple and understood-by-all definition, the following is proposed: “a system to ensure that a pipeline network is safe, reliable, sustainable and optimised.”
Bureau Veritas’ PIM step-by-step approach is comprised of the following six stages:
- Policy and strategy: where are you now, where do you want to go and what should you put in place to reach your target?
- Methodology: do you want/need to use a risk-based, threat-based or consequence-based approach or something else?
- Data: start thinking about data collection and modelling only once the policy and strategy, and methodology have been identified.
- Systems and tools: once policy and strategy have been defined, methodology has been selected and data gathered, select the most appropriate tool to use (simple or sophisticated software).
- Study and analysis: the tools will enable an assessment of the pipeline network and definition of your inspection plans.
- Inspection and expertise: after implementing the inspection plans, specific expertise should be used to analyse the inspection results. The knowledge gained will then be used during the regular PIM review.
Company policy and methodology is key
As a first step, it is important to properly define the roots of the PIM approach chosen. Local constraints, in-house specific requirements, international guidelines and adequacy will help set up the basis of the methodology to be developed.
The most appropriate approach will be found by referencing the local regulatory body’s policy (safety/inspections-oriented or risk/threat mitigation-oriented) along with common practices and existing procedures, the assets’ typology and age, the existing international best practices, and the level of in-house expertise. Several approaches may be considered, such as qualitative versus quantitative, threat-based versus damage-based, and probabilistic versus deterministic.
The identification of expected results (primary target) should be properly specified: restricted impact on the environment, corrosion-related failure prevention, inspection strategy, and means of mitigation. This will ensure that the PIM is set up in-line with the project targets.
The PIM methodology can then be chosen and tailored to the specific case.
A PIM approach that may be suitable for one operator may not be acceptable for another operator.
Only once the methodology is developed and understood by all project stakeholders can the data and tool issues be properly addressed.
Data and tools: you don’t need a video game
Data management is a crucial task within the PIM process. It should provide a complete system capable of delivering the right data in the right shape, at the right place and for the right purpose. This requires very organised and step-wise work.
By defining the PIM strategy, key performance indicators can be identified and data requirements can be defined. This refers to the format, accuracy, and frequency requirements of the data. It is also beneficial to think mid-term about PIM requirements, for example, consider the tools that will be used and any modifications that might be planned to the asset.
Finally, it is advised that data quality control/quality assurance is performed to obtain the ‘green light’ before processing data into the PIM process.
The same applies to the tools to be used. While there is a temptation to use a very ‘high tech’ tool, the most important consideration is for an easy-to-use tool that will monitor the health of the pipeline network and point out pipeline segments which require mitigation or inspection due to their threat or risk levels.
Depending on the pipeline’s length, a Microsoft Excel macro could be sufficient. However, an automated and integrated tool is necessary for longer pipelines or complicated networks.
Study and analysis: from integrity assessment to inspection plans
Now with an operational and clear pipeline database along with a PIM tool, the chosen PIM methodology can be implemented. The PIM tool will enable the first integrity assessment to be carried out – ‘first’ because PIM is a continuous loop where previous results are used to improve the following assessments. Following this, a ‘pipeline prioritisation’ can be obtained, which will form the basis to analyse and understand the pipeline network’s condition. Frrom here, the PIM can be expanded to include a mitigation plan plus inspection plan.
Here an important question arises: what actions should be performed in order to reduce the threat/risk level on the pipeline? Should the inspection frequency be increased, a mitigation action applied, or both? The decision should rely on the inspection and mitigation policies defined in the first step of the PIM process.
Inspection and expertise: method qualification and trustworthy results
Undoubtedly, one of the most visible steps of the PIM process is the inspection itself. There are many inspection techniques for pipelines but the most widely used are magnetic-flux leakage and ultrasonic testing. The in-line inspection provider should be selected very carefully, evaluating their qualification by referring to the specific requirements of the project.
The most critical part of this process is the analysis of results and the expertise required to obtain crucial information on the actual condition of the pipeline.
An effective PIM should be comparable to a high-quality management system.
This article started by outlining that a PIM is a system allowing operators to ensure that their pipeline networks operate in a safe, reliable, sustainable and optimised way.
If neglected and unused, even the most expensive and ‘high tech’ PIM solution will fail to be beneficial. A PIM needs to be accepted and embedded into the company’s processes.
Therefore, as a conclusion, Bureau Veritas would advise operators to keep in mind that a PIM, like a quality management system, is a continuous process. Therefore it is important to break down the PIM plan into manageable steps.
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