In the world of pipeline integrityThe capability of a pipeline to perform its intended function safely and reliably throughout its life. It includes a range of factors, including the structural …, laminations present a unique challenge due to their often-misunderstood nature and potential to significantly compromise a pipeline's health.
In this article, we’ll explore how laminations originate, the threat they pose to a pipeline's integrityThe capability of a pipeline to perform its intended function safely and reliably throughout its life. It includes a range of factors, including the structural …, and the best techniques and methodologies for detecting them. We’ll also outline how NDT Global assesses, categorizes, and prioritizes different types of laminations using a combination of data-driven tools and the expertise of our seasoned professionals.
The Many Challenges of Pipeline IntegrityThe capability of a pipeline to perform its intended function safely and reliably throughout its life. It includes a range of factors, including the structural … Management
Increasing economic pressures on energy producers worldwide mean fewer new pipelines are being constructed. That’s forcing pipeline managers in the oil and gas industry to rely heavily on aging infrastructure while trying to find ways to improve and extend the life of these assets.
Over time, ad hoc point repairs and improvements result in original pipeline infrastructures comprising a complex “patchwork” of varying pipe manufacturers and vintages, making it difficult to predict, assess, and detectTo sense or obtain a measurable indication from a feature.
anomalies—such as laminations—and other points of weakness.
Diverse physical environments only add to the complexity of pipeline infrastructure management. A single pipeline systemAll portions of the physical facilities through which liquid or gas moves during transportation. This includes pipe, valves, and other appurtenances attached to… may cross different terrains, temperatures, and elevations within the same run, making InspectionThe systematic process of visually examining, testing, or monitoring pipeline components to assess their condition, integrity, and compliance with regulatory re… and maintenance extraordinarily complicated.
What are Pipeline Laminations and Why Can They Be Cause for Concern?
Laminations are planes of non-fusion within steel plates that typically occur during the pipe manufacturing process when discontinuities or porosities in the plate steel are rolled out and flattened. They are most frequently observed in older pipelines (pre-1980s) due to the less rigorous quality controlProcess of assuring a task or process was performed as intended, meeting or exceed specified requirements and standards. It involves monitoring, inspecting, and… mechanisms employed at the time, but it’s not impossible for them to be present in modern pipelines.
Not every laminationA planar discontinuity, usually oriented parallel or near parallel to the pipe surface, is the result of inconsistencies in the material used in the pipe manufa… represents a significant threat or riskA measure of loss in terms of both the incident likelihood of occurrence and the magnitude of the consequences., but some can create planes of weakness within the pipe’s interior that can compromise the pipe’s long-term health and viability. For this reason, it’s vital to identify laminations and assess their individual impact as well as potential interactions with other defects or anomalies as part of a robust pipeline integrityThe capability of a pipeline to perform its intended function safely and reliably throughout its life. It includes a range of factors, including the structural … management strategy.
Pipeline Laminations: Types and Risks
Laminations come in various forms, each with its own set of risks and implications:
Planar laminations lie parallel to the pipe wall, remain on a single plane across the middle of the pipe’s steel wall, and are generally stable.
Sloping laminations are inclined towards the interior or exterior surface of the pipeline, posing a higher riskA measure of loss in terms of both the incident likelihood of occurrence and the magnitude of the consequences..
Surface-breaking laminations connect directly to the internal or external surface of the pipeline, presenting a significant threat.
Bulging laminations protrude from the surface, indicating severe structural and integrityThe capability of a pipeline to perform its intended function safely and reliably throughout its life. It includes a range of factors, including the structural … issues.
HydrogenA natural gas element used in non-destructive testing,
hydrogen is a chemical element with the symbol "H" and atomic number 1. It is the lightest and most abun…-induced blistering laminations have distinctive bubbles and circular patterns. Depending on their size and position, these laminations can significantly degrade the mechanical performance of pipeline steel.
Overlapping laminations are high-density layers that obscure inspectionThe systematic process of visually examining, testing, or monitoring pipeline components to assess their condition, integrity, and compliance with regulatory re… and assessment.
While planar laminations often don't require immediate action, most other types of laminations can significantly erode the thickness of pipelines and thus require urgent assessment and remediationThe appropriate actions taken to address or rectify issues, deficiencies, or anomalies identified in a pipeline system. It involves implementing corrective acti….
What Technologies Are Available to Assess Laminations?
Two primary types of technology are used across the industry to assess pipeline laminations.
Ultrasonic (UTSystems used in non-destructive testing that utilize sound waves to detect, identify, and measure anomalies within a pipeline integrity test or management progr…) Metal LossRefers to the reduction in material thickness or cross-sectional area of a pipe due to corrosion, erosion, or other forms of degradation. technology, which utilizes straight beam or compression wave UTSystems used in non-destructive testing that utilize sound waves to detect, identify, and measure anomalies within a pipeline integrity test or management progr…, is the most common and effective way to identify and assess laminations and size metal lossRefers to the reduction in material thickness or cross-sectional area of a pipe due to corrosion, erosion, or other forms of degradation. .
UT CrackA fracture or discontinuity in the wall of a pipeline, where the material is separated or broken, potentially compromising the integrity and safety of the pipel… technology, while not necessarily designed to detectTo sense or obtain a measurable indication from a feature.
and address mid-wall laminations, can also provide some value, especially when laminations have some form of radial componentAny physical part of the pipeline, other than line pipe, including but not limited to valves, welds, tees, flanges, fittings, taps, branch connections, outlets,….
NDT Global’s Approach to Detecting, Assessing, and Managing Laminations
At NDT Global, we approach laminations by uniting precision technology with deep analytical expertise. Here’s an overview of how we go about detecting, assessing, and managing laminations.
1. Detecting Laminations with UTSystems used in non-destructive testing that utilize sound waves to detect, identify, and measure anomalies within a pipeline integrity test or management progr… Metal LossRefers to the reduction in material thickness or cross-sectional area of a pipe due to corrosion, erosion, or other forms of degradation. Technology
UT Metal Loss technology is our primary tool for identifying and sizing laminations.
UTSystems used in non-destructive testing that utilize sound waves to detect, identify, and measure anomalies within a pipeline integrity test or management progr… Metal LossRefers to the reduction in material thickness or cross-sectional area of a pipe due to corrosion, erosion, or other forms of degradation. technology provides detailed wall thickness measurements and detects mid-wall features like laminations with unparalleled clarity. It can identify planar laminations by their uniform shape and detectTo sense or obtain a measurable indication from a feature.
sloping and surface-breaking laminations due to the distinct wall thickness patterns they introduce.
As part of the assessment exercise, our teams leverage UTSystems used in non-destructive testing that utilize sound waves to detect, identify, and measure anomalies within a pipeline integrity test or management progr… Metal LossRefers to the reduction in material thickness or cross-sectional area of a pipe due to corrosion, erosion, or other forms of degradation. technology to take three critical measurements:
Reference Wall ThicknessThe specified or intended thickness of a pipe's wall as determined by the design or engineering standards. It is typically denoted as a nominal value and is use…: The nominal wall thicknessThe specified or intended thickness of a pipe's wall as determined by the design or engineering standards. It is typically denoted as a nominal value and is use… in the area of the laminationA planar discontinuity, usually oriented parallel or near parallel to the pipe surface, is the result of inconsistencies in the material used in the pipe manufa….
Slope of the Lamination: Measured at the start and end points of the anomalyAny irregularity, defect, or abnormal condition identified in a pipeline system that deviates from the expected or normal operating condition. Anomalies in pipe….
Effective Length: The total length of the laminationA planar discontinuity, usually oriented parallel or near parallel to the pipe surface, is the result of inconsistencies in the material used in the pipe manufa… across the pipe wall.
Using this data, they can map laminations precisely and accurately quantify reductions in wall thickness due to surface-breaking or sloping laminations.
Addressing Complex Issues
Bulging laminations and hydrogenA natural gas element used in non-destructive testing,
hydrogen is a chemical element with the symbol "H" and atomic number 1. It is the lightest and most abun…-induced blistering are more complex issues that our expert use of UTSystems used in non-destructive testing that utilize sound waves to detect, identify, and measure anomalies within a pipeline integrity test or management progr… Metal LossRefers to the reduction in material thickness or cross-sectional area of a pipe due to corrosion, erosion, or other forms of degradation. technology can detectTo sense or obtain a measurable indication from a feature.
and address effectively:
Bulging laminations are easily identified due to their distinctive oval patterns in wall thickness and a reduction in standoff measurements.
HydrogenA natural gas element used in non-destructive testing,
hydrogen is a chemical element with the symbol "H" and atomic number 1. It is the lightest and most abun…-induced blistering produces circular patterns indicative of blistering within the pipeline material. Our team uses distinctive ultrasonic patterns to identify these anomalies accurately.
So, using UTSystems used in non-destructive testing that utilize sound waves to detect, identify, and measure anomalies within a pipeline integrity test or management progr… Metal LossRefers to the reduction in material thickness or cross-sectional area of a pipe due to corrosion, erosion, or other forms of degradation. technology allows us to not only clearly detectTo sense or obtain a measurable indication from a feature.
a wide range of laminations, but also to size them and perform the necessary in-depth assessments.
2. Supporting Detection with UTSystems used in non-destructive testing that utilize sound waves to detect, identify, and measure anomalies within a pipeline integrity test or management progr… CrackA fracture or discontinuity in the wall of a pipeline, where the material is separated or broken, potentially compromising the integrity and safety of the pipel… Technology
UT Crack technology (ShearWave) complements UTSystems used in non-destructive testing that utilize sound waves to detect, identify, and measure anomalies within a pipeline integrity test or management progr… Metal LossRefers to the reduction in material thickness or cross-sectional area of a pipe due to corrosion, erosion, or other forms of degradation. by honing in on any radial components present in sloping laminations. Sloping laminations that surface-break are particularly visible using this technology.
For instance, a sloping laminationA planar discontinuity, usually oriented parallel or near parallel to the pipe surface, is the result of inconsistencies in the material used in the pipe manufa… that connects to the interior surface (ID) will produce a corner echo in the UTSystems used in non-destructive testing that utilize sound waves to detect, identify, and measure anomalies within a pipeline integrity test or management progr… CrackA fracture or discontinuity in the wall of a pipeline, where the material is separated or broken, potentially compromising the integrity and safety of the pipel… data, signaling a surface-breaking anomalyAny irregularity, defect, or abnormal condition identified in a pipeline system that deviates from the expected or normal operating condition. Anomalies in pipe…. This echo allows our analysts to categorize the lamination appropriately and recommend appropriate remedial actionThe appropriate actions taken to address or rectify issues, deficiencies, or anomalies identified in a pipeline system. It involves implementing corrective acti….
"UT Metal LossRefers to the reduction in material thickness or cross-sectional area of a pipe due to corrosion, erosion, or other forms of degradation. technology is the optimal technique to detectTo sense or obtain a measurable indication from a feature.
, identify, and size laminations. Our team's expertise ensures accurate data interpretation and actionable insights that empower better decision-making." - Ryan Sikes, Product Manager at NDT Global
Key Takeaways: Using UTSystems used in non-destructive testing that utilize sound waves to detect, identify, and measure anomalies within a pipeline integrity test or management progr… Metal LossRefers to the reduction in material thickness or cross-sectional area of a pipe due to corrosion, erosion, or other forms of degradation. Technology vs. UT CrackA fracture or discontinuity in the wall of a pipeline, where the material is separated or broken, potentially compromising the integrity and safety of the pipel… Technology
UT Metal Loss technology is the optimal technique for detecting, identifying, and sizing laminations.
UTSystems used in non-destructive testing that utilize sound waves to detect, identify, and measure anomalies within a pipeline integrity test or management progr… CrackA fracture or discontinuity in the wall of a pipeline, where the material is separated or broken, potentially compromising the integrity and safety of the pipel… technology should support UT Metal LossRefers to the reduction in material thickness or cross-sectional area of a pipe due to corrosion, erosion, or other forms of degradation. technology in certain scenarios. For example, UT Crack technology can add significant value in cases where laminations have potential radial components—whether that's a surface breaking or an advanced sloping element. UT Metal Loss technology alone may not be able to detectTo sense or obtain a measurable indication from a feature.
radial components present in laminations.
It’s not possible, however, to accurately size laminations using UTSystems used in non-destructive testing that utilize sound waves to detect, identify, and measure anomalies within a pipeline integrity test or management progr… CrackA fracture or discontinuity in the wall of a pipeline, where the material is separated or broken, potentially compromising the integrity and safety of the pipel… diagnosis technology, and any findings should be treated as informative only unless additional assessments or correlations with additional data sets are performed.
In cases where pipelines have dirty steel or where there’s a high prevalence of known laminations, we may recommend combining the use of these two technologies, i.e., Metal LossRefers to the reduction in material thickness or cross-sectional area of a pipe due to corrosion, erosion, or other forms of degradation. technology to detectTo sense or obtain a measurable indication from a feature.
and size laminations and UTSystems used in non-destructive testing that utilize sound waves to detect, identify, and measure anomalies within a pipeline integrity test or management progr… CrackA fracture or discontinuity in the wall of a pipeline, where the material is separated or broken, potentially compromising the integrity and safety of the pipel… technology to assess and/or eliminate the riskA measure of loss in terms of both the incident likelihood of occurrence and the magnitude of the consequences. of associated radial components.
By combining and correlating those two data sets, we can obtain a holistic view of all laminations present and perform a level of assessment that a single technology may not necessarily allow.
3. Comprehensive Categorization
Once the presence of laminations has been confirmed, and we’re clear on their nature and size, the next step is determining how they should best be addressed or if any action is required at all. (As we mentioned earlier, parallel or planar laminations don’t necessarily justify further action or assessment.)
In categorizing identified laminations (whether they were detected through the use of UTSystems used in non-destructive testing that utilize sound waves to detect, identify, and measure anomalies within a pipeline integrity test or management progr… Metal LossRefers to the reduction in material thickness or cross-sectional area of a pipe due to corrosion, erosion, or other forms of degradation. technology alone or in conjunction with UT CrackA fracture or discontinuity in the wall of a pipeline, where the material is separated or broken, potentially compromising the integrity and safety of the pipel… technology), we take into account various aspects, including:
The type and nature of the laminationA planar discontinuity, usually oriented parallel or near parallel to the pipe surface, is the result of inconsistencies in the material used in the pipe manufa…
Its location and size/measurement
Its distance from or potential interaction with any other featureGeneral term for an anomaly detected during an assessment. Features can be anomalies, components, nearby metallic objects, welds, appurtenances, or some other i… or installation
Whether it's manufacturing or hydrogenA natural gas element used in non-destructive testing,
hydrogen is a chemical element with the symbol "H" and atomic number 1. It is the lightest and most abun…-induced
NDT Global’s integrityThe capability of a pipeline to perform its intended function safely and reliably throughout its life. It includes a range of factors, including the structural … services specialists will then categorize laminations into three primary categories:
Category A (Insignificant): These laminations are typically planar, lie parallel to the pipe surface, and have no contact or interaction with welds or other features. As such, they don’t necessarily require additional assessment or action.
Category B (Assessment Required): These laminations have varying depths—whether sloping or potentially surface-breaking—and have significant weldLocalized coalescence of metals produced by heating the materials to the welding temperature, with or without the application of pressure, or by the application… contact or adjoin to a weld. Additionally, any hydrogenA natural gas element used in non-destructive testing,
hydrogen is a chemical element with the symbol "H" and atomic number 1. It is the lightest and most abun…-induced or blistering laminationA planar discontinuity, usually oriented parallel or near parallel to the pipe surface, is the result of inconsistencies in the material used in the pipe manufa… would meet Category B assessment requirements.
Category C (Immediate Action Required): Laminations interacting with other significant anomalies, such as metal lossRefers to the reduction in material thickness or cross-sectional area of a pipe due to corrosion, erosion, or other forms of degradation. or cracking.
Prioritizing Laminations
Next, let’s look at how we prioritize laminations that require additional assessment or immediate action (i.e., Those in categories 2 and 3.)
If we discover blistering laminations or those that interact with welds, we follow API 579 guidelines to assess them based on contact distance and prioritize action accordingly. Laminations within 25mm (1 inch) or twice the wall thickness of a weldLocalized coalescence of metals produced by heating the materials to the welding temperature, with or without the application of pressure, or by the application… are considered interacting. We then categorize these interactions into three priority levels:
Priority 1: Significant contact with welds requires immediate verificationThe process of confirming or verifying that an inline inspection (ILI) meets specific requirements, standards, or expectations. It involves assessing and evalua….
Priority 2: Intermediate contact, requiring verificationThe process of confirming or verifying that an inline inspection (ILI) meets specific requirements, standards, or expectations. It involves assessing and evalua… if cracking is observed.
Priority 3: Clear separation from welds, considered acceptable.
The Power of Clarity™ in Action
As we’ve explored, assessing every pipeline laminationA planar discontinuity, usually oriented parallel or near parallel to the pipe surface, is the result of inconsistencies in the material used in the pipe manufa… thoroughly and taking the appropriate action based on its type, category, and riskA measure of loss in terms of both the incident likelihood of occurrence and the magnitude of the consequences. is a complex and multi-faceted endeavor.
By leveraging our "Power of Clarity" philosophy, NDT Global brings together UTSystems used in non-destructive testing that utilize sound waves to detect, identify, and measure anomalies within a pipeline integrity test or management progr… Metal LossRefers to the reduction in material thickness or cross-sectional area of a pipe due to corrosion, erosion, or other forms of degradation. and UT CrackA fracture or discontinuity in the wall of a pipeline, where the material is separated or broken, potentially compromising the integrity and safety of the pipel… technologies—and the best people—to capture the best diagnostic data. This provides pipeline operators with deep insights into their assets, empowering them to make the best decisions that ultimately ensure safety, business efficiency, and environmental stewardship.
Let us help you navigate the complexities of laminations and deliver the "Power of Clarity" for your pipeline's integrityThe capability of a pipeline to perform its intended function safely and reliably throughout its life. It includes a range of factors, including the structural ….
Let's talk.
