Image A Closer Look: Effective Corrosion Management
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Collaborating with other members of the oil and gas industry means sharing knowledge and experiences to gain a deeper understanding of the unique challenges facing operators today. Through this valuable exchange, we grow closer to achieving the goal of zero incidents.

The workshop entitled “Corrosion Control and Management: Proactive, preventive and predictive” took place in Kuala Lumpur, Malaysia. This full day event was attended by 30 participants from diverse backgrounds, including engineers, technical authorities, integrity managers, and major operators within the Asia Pacific region.
 

Presentations were given on key topics surrounding a main theme: effective corrosion management in onshore and offshore pipeline assets in consideration of the significant challenges in recent years for the oil and gas industry. These include maintaining production against a backdrop of ageing assets, shortage of technically-skilled people, spiraling costs, and falling oil prices. At the close of the event, an engaging panel discussion and open Q&A took place, in which ROSEN’s Subject Matter Experts (SMEs) addressed some of the critical technical issues within the Asia Pacific region, such as Top-Of-Line Corrosion.  

Aging Assets

The first presentation of the workshop, “Aging Assets: Optimization of Chemical & Pigging Regimes,” examined the unique challenges facing aging systems and possible strategies to successfully and safely implement Asset Life Extension. Topic-related industry standards and experiences from projects in the North Sea, one of the most mature operational basins, were presented.

Corrosion & Costs

A topic of discussion in this presentation focused on the importance of chemical and pigging regimes to manage the occurrence of corrosion in pipeline infrastructures. This was examined through detailed case studies that included the presentation of design/operational data vs. direct examination findings (e.g. In-Line Inspection). While the implementation of corrosion control programs is essential in obtaining superior long-term operational integrity, it was stressed that this can be deeply impacted by the initial pipeline design.

The technical (and cost) issues related to ‘‘Overdoing” (e.g. chemical overdosing) and “obsolescence,” which could be partly associated with a lack of system awareness or shortage of technical expertise, were also addressed. Strategies were introduced, based on sound technical and cost analysis, on how to optimize mitigation and control regimes in order to successfully achieve lifetime extension while controlling costs.

Challenging Pipelines

The second presentation topic, “Challenging Pipelines: Pipeline Internal Corrosion Direct Assessments & Intelligent Predictive Corrosion Modelling,” discussed the application of Internal Corrosion Direct Assessment (ICDA) methodology in order to infer the internal condition and integrity of onshore and offshore pipelines. Critical prerequisites to the implementation of ICDA were examined to enhance the reliability of the method. The input of SMEs, the use of suitable modelling tools, the understanding of limitations in processes and tools - which are grasped by the SMEs - and the availability and quality of essential data were considered as prerequisites for proper implementation.

ICDA Method

Case studies were reviewed to demonstrate the effectiveness of the ICDA method, provided it is properly implemented. A key observation was that Direct Assessment (DA) approaches could, and should, be used to validate and optimize ILI findings for piggable pipelines. One example used was the linearity of corrosion growth rates identified between two different ILIs. However, higher or lower corrosion rates may apply, depending on the nature and magnitude of operational deviation and the intrinsic nature of the corrosion mechanism. Furthermore, the knowledge and data relating to a piggable pipeline of a similar operational framework could be applied to an unpiggable pipeline in order to infer its condition. However, the wrong analysis of these corrosion growth rates would negatively affect remaining life evaluations and future integrity management plans. Therefore, especially if intrapolations or extrapolations need to be conducted, a corrosion engineer should assist to confirm the validity and the limits under which this data could be applied.

New Developments

Knowledge and data are great assets to be used. Exclusive insight into a new development by ROSEN experts, the Internal Corrosion Model (ICP), was presented as an example of this. The ICP is based on the combination of big data and Artificial Intelligence, and implements ROSEN’s corrosion and flow assurance expertise, and its direct access to a vast in-line inspection database. When applied, this new model will help to further enhance pipeline prediction capabilities, the reliability of Direct Assessment (DA) methodologies, validation of ILIs, and will ultimately support further development of more reliable integrity management programs.

Conclusion

A final takeaway from the workshop is that a great number of strategies, standards, models, and tools is available to support operators in managing asset integrity, whether it is newly designed, mature, or aging. However, emphasis must be placed upon reliability, competency, and expertise during the implementation process of these resources. Cost control and reductions shall also only be conducted in a sensible manner on the basis of - and not to the detriment of - sound technical processes and analysis. Only then can an effective control of costs be achieved without negatively affecting the necessary understanding and safe management of the asset integrity and condition.