Corrosion Growth Assessment
Enabling accurate insights for reliable pipeline integrity decisions
Corrosion remains one of the most persistent threats to pipeline integrity, often developing slowly, invisibly, and unevenly across long distances and varied environments. Across regions where pipelines run through deserts, wetlands, mountain corridors, urban industrial corridors, or offshore routes, a clear understanding of corrosion behavior is essential for maintaining operational safety and for optimizing inspection, repair, and maintenance budgets
ROSEN’s Corrosion Growth Assessment (CGA) services transform inspection data into a clear understanding of how corrosion evolves over time. By combining advanced analytics with deep expertise in integrity engineering, we help operators uncover active threats, diagnose potential causes, and forecast how corrosion will progress. This supports more confident and efficient decision-making across your entire asset lifecycle.
Users of ROSEN’s CGA services consistently gain:
Deep understanding of corrosion activity, improving long-term planning
Increased accuracy in corrosion growth estimates when using pro service levels
Greater confidence in the remaining safe operational life of assets
Reduced impact of sizing differences with signal-level comparisons
Optimized inspection and rehabilitation strategies to reduce cost and downtime
A holistic approach to corrosion diagnosis
Every CGA begins with a review of all available pipeline data, where our integrity/corrosion engineers review historical and current information to determine internal and external corrosion distribution profiles along the pipeline length. This is an essential input into the segmentation of the pipeline into zones with distinct internal and external corrosion susceptibilities and provides insight into understanding long-term trends and defining suitable mitigation strategies.
Once this foundation is established, ROSEN determines historical corrosion growth rates (CGRs) for all reported corrosion anomalies by comparing recent and previous ILI data, using proprietary methodologies and software. These rates form the basis for predicting future behavior: how quickly corrosion is progressing, which areas pose the greatest concern, and where interventions will have the greatest impact. The pipeline is then segmented into internal and external corrosion growth profiles, for input into future integrity management calculations & strategies.
The precision of these insights depends on the availability and comparability of inspection data. When repeat ILI inspections are available, especially when using comparable technologies, such as MFL-A, CGR estimation becomes significantly more accurate. ROSEN’s Automated Signal Comparison and Normalization (AutoSCAN) technology offers market-leading reliability by comparing all metal loss indications at the signal level, minimizing the common‑mode sizing errors that typically reduce the confidence of conventional assessments.
To meet differing needs, ROSEN offers a scalable suite of Corrosion Growth Assessment options. Each service level builds upon the previous one, ensuring that operators, whether managing low-risk lines or critical, hard-to-access assets, can select the approach that best aligns with their goals, budget, and data quality.
This tiered structure is designed to provide the right balance of accuracy, depth of analysis, and investment for every situation.
Three levels of Corrosion Growth Assessment
This foundational service compares reported anomalies between two inspection runs using a structured, conservative box-matching approach. It is ideal for operators seeking a cost-effective method to obtain credible CGR estimates when ILI repeatability or technology alignment is limited and provides meaningful insights into whether active corrosion is present and how it has changed over time.
CGA Box Matching provides a robust, conservative, and universally applicable starting point for understanding corrosion behavior. Its main strength lies in its flexibility: because it relies on reported anomalies and standard matching criteria, it can be used with any ILI vendor, even when inspection technologies differ or historical data quality is inconsistent. This makes it particularly valuable for pipelines where inspection conditions are not ideal or where repeatability between inspections may vary.
As a general-purpose solution, CGA Box Matching offers operators a credible first assessment of corrosion activity, identifying whether corrosion is progressing and at what rate. Despite its conservative nature, it still supports operational planning, helping operators determine where corrosion activity is occurring and how it may influence future repairs or inspection intervals. It is especially advantageous for low-risk pipelines with good accessibility and lower repair costs, where simplicity and cost-efficiency outweigh the need for high-precision signal-level comparisons.
Building on box matching, CGApro incorporates selective manual signal comparison to enhance the accuracy of depth change estimates. It also introduces pipeline segmentation based on key indicators, making it especially beneficial when switching between ILI vendors or when corrosion mechanisms vary along the pipeline. With improved data clarity, operators can better understand corrosion behavior and make more precise predictions about the future integrity of their assets.
CGApro expands significantly on the standard approach by adding pipeline segmentation and optional manual signal comparisons, enabling a more refined and accurate view of corrosion development. This makes things clearer, especially when using different ILI vendors or when the data formats and sizing algorithms are different. The selective signal-level evaluation sharpens the accuracy of depth-difference estimates, offers visual confirmation of corrosion activity, and reduces some of the uncertainty inherent in pure box matching.
One of its strongest advantages is segmentation: CGApro divides the pipeline into regions based on internal and external corrosion susceptibility, allowing operators to understand how corrosion is behaving along the pipeline length. This segmentation enables more tailored forecasting of future corrosion growth, making CGApro ideal for medium-risk pipelines where moderate repair costs, varied environments, or vendor transitions demand a more nuanced assessment. Thanks to improved data reliability and corrosion segmentation, operators avoid unnecessary excavations caused by overly conservative estimates.
Overall, CGApro improves the accuracy of corrosion growth rates and offers operators greater confidence in their long term integrity planning.
As ROSEN’s most advanced CGA service, CGApro with AutoSCAN represents the highest level of diagnostic precision in corrosion growth assessment. It uses automated signal correlation and normalization, comparing every metal loss indication between repeat ROSEN MFL A inspections. This comprehensive signal level matching eliminates most common mode sizing and alignment errors, which are typically the biggest source of uncertainty in corrosion growth rate estimation.
With a clear understanding of maximum CGRs in each segment, operators gain unparalleled confidence in planning repairs, extending reinspection intervals, and minimizing unnecessary digs, especially in remote or high-risk environments.
Because it can distinguish true new anomalies from reporting differences, CGApro with AutoSCAN drastically increases both matching success and reliability of results. This allows estimation of historical depth changes with exceptional accuracy, enabling operators to confidently base integrity decisions on realistic, not overly conservative, corrosion behavior. As a result, pipeline segments are assigned maximum CGRs rather than conservative averages, giving operators a clearer understanding of worst-case growth scenarios and supporting optimized long-term repair and inspection strategies.
One of the strongest advantages of CGApro with AutoSCAN is its ability to minimize the number of required digs. Because the data is far less conservative and significantly more accurate, operators can eliminate a large portion of unnecessary excavations, a factor that delivers major cost savings, particularly for pipelines in remote, environmentally sensitive, or challenging terrain. In high-risk systems, where repairs are expensive and difficult, this efficiency can fundamentally shift integrity planning strategy.
By providing the least conservative, most precise corrosion growth analysis, CGApro with AutoSCAN enables operators to safely extend inspection intervals, reduce unnecessary digs, and better allocate maintenance budgets.
CGA services help quantify corrosion growth and support better integrity decisions. By combining CGA results with ROSEN’s Fitness for Service (FFS) assessments, operators receive a comprehensive view of their asset’s current condition and its future outlook. This integrated approach clarifies which anomalies require immediate attention, which require monitoring, and which may not pose a significant risk. It also highlights underlying corrosion mechanisms, helping operators refine mitigation, monitoring, and maintenance plans.
This full-picture perspective is especially valuable, where varying environments can create distinct corrosion patterns along a single pipeline. Understanding these variations enables more effective resource allocation and enhances overall operational reliability.
Get started with CGA
Fill out this form to connect with a ROSEN pipeline integrity expert and discuss how CGA Box Matching, CGApro, or CGApro with AutoSCAN can support your corrosion assessment and decision‑making.