Table of Contents
1 Introduction
Pipeline workers and industrialists are under growing pressure to maintain the reliability of their network of pipelines from regulatory bodies, governing agencies, and environmentalists, as well as financial compulsion to cut maintenance costs.
The scope of modern non-destructive testing (NDT) methods over older ones, including manual pit gauge, is growing in popularity. The most recent advancements in 3D optical technology satisfy the requirement for faster, higher-quality inspections and repeatable results.
Through the use of a contactless dynamic referencing mechanism in place of conventional mechanical connections, the scanner has ability to capture the affected area by ensuring consistent precision in a dynamic location.
Figure 1 Corrosive Pipeline
The network of pipelines must be inspected by the pipeline workers or inspectors by themselves or by third-party NDT inspection services. By using ultrasonic (UT) or magnetic flux leakage (MFL) techniques, ILI (in-line inspection) equipment enables the detection of significant points with mechanical damage or exterior corrosion. The law stipulates that critical sections must be having a prove-up from the exterior of the pipeline, which often necessitates excavation.
To determine the proper remedy, a variety of procedures may be employed as a direct evaluation methodology. With the most recent 3D optical developments from quality control of metrology and now applied to NDT applications, each approach has certain limits that may be reduced or avoided.
Using a pit gauge for manual observations and measurements makes the assessment reliant on the abilities of the inspector. Due to the large number of data points needed, it produces inconsistent findings, a drawn-out inspection procedure, and poor report quality. Owing to water leakage and misalignment of probes on uneven surfaces, UT systems need continual water coupling, which is challenging. The front wall echo interface is another factor that reduces precision. UT probe positioning requires a mechanical scanner to accommodate various pipe sizes, which increases complexity and decreases mobility.
Additionally, a full-coverage C-Scan needs a high-rate displacement due to the tiny dimensions of a UT probe, which adds to the examination duration. When taking into account a smooth exterior surface, this approach is more suited for interior corrosion. Conventional or traditional one-line laser systems provide a significantly wider reach and do not need a water connection. Unfortunately, because of the physical fitting, they also have significant mobility constraints.
The most recent advancements in 3D technology preserve the benefits of the traditional approach thereby addressing the majority of related drawbacks. The 3D scan is appropriately scaled to replicate the actual shape and makes it simple to see exterior flaws. To make decision-making easier, the analysis software needs to be capable to handle a big volume of data and provide a report in a matter of minutes with thorough findings.
2 The need for NDT 3D scanning
Processes and services for 3D laser scanning might are likely to be very common. The 3D technique also enables controlled laser beam guidance for distance measurements. The unit’s inbuilt rotary encoder controls the scan motions by switching out various scan mirrors for laser beam focusing. Businesses can precisely record their goods thanks to 3D laser scanning. By utilizing a 3D laser scan, companies can readily assess how much substance will be needed to manufacture the identical thing.
It is possible to create the completed item using traditional techniques, maintaining the impression of excellent quality. The process of making digital copies of real-world items is called 3D scanning. The goal of 3D scanners is to precisely measure, digitize, reproduce, and adjust their dimensions.
Figure 2 Inspection of pipeline
These faster scan systems provide outstanding results because the information and the resolution are the essential elements of a top-quality 3D scanning. Its quality is now improved by high-quality software, and this top-notch data collection is often utilized to print the model.
3D scanning has been used in production for a very long time. Industries needed dimensions measurements to ensure that all items met quality standards. The production of more sophisticated medical devices has expanded the usage of dimensional measurements in the medical sector, and 3D scanning is a useful tool for measuring and assessing medical components.
The ability to customize wearable devices, such as braces and implants, increases patient convenience are top benefits of it. This technique often produces results without having to contact directly with patients, and it does it in a steady and timely manner. There are several benefits over traditional measuring methods. In comparison to manual measurement, which is slower and limited in the amount of data it can collect, 3D contactless scanning enables the collection of large sets of data more quickly.
3 What level of expertise is needed?
As pipeline owners and operators develop their networks, there is an increase in the need for trained and competent inspectors. Finding pipeline inspectors in the current market who have all the required training and are knowledgeable about several various traditional measuring procedures and instruments is quite challenging.
It may take a while and be expensive to prepare technical staff in order to get license of inspectors of pipeline. The workers are can commit errors in spite of proper training. The working environment is unfavorable, and turnover is quite high. Therefore, solutions are needed to address these concerns with the inspection crew.
4 Current Issues & Challenges related to pipeline inspection
Because pipelines are naturally complicated, it may take a lot of time to examine them for damage including corrosion, gouges, weld arc strikes, cracking, and dents. The precision, dependability, and repeatability of traditional approaches, which were formerly manual, depended on the technician’s expertise and were often hampered by the environment on any particular inspection day.
Based on the pipe segment to be examined, these manual inspection approaches sometimes need time-consuming equipment setups and measurement durations that might last hours or even days. Additionally, the inspection teams’ capacity to detect additional significant information or damage may be hampered by the geometry of the pipeline’s intricacy and the unstable excavation environment.
After the data is gathered, more time is required to analyze and confirm the measurements locally before sending them to engineers for additional evaluation off-site.
The more precise the readings are for burst pressure estimates using manual methods, the finer the grid. Accordingly, a 2X smaller grid corresponds to 4X more measurements. It takes time to measure several data points, and the technician must return to the trench to repair any measurement mistakes when these data points need to be re-measured.
Since they may doubt the veracity and accessibility of the data, inspectors and engineers might lack the confidence to make their concluding remarks.
5 NDT 3D Scanning: a solution to every problem
Pipeline workers, stakeholders, and NDT service suppliers may all gain from using portable 3D scanners since they offer a simple, quick, and efficient tool for all kinds of pipeline integrity examinations. Including integrated “Pipecheck” software, handheld scanners provide a comprehensive 3D image (with structure, texture, geometry, and color).
As a result, it is highly simple to get precise data related to measurements on pipes of length up to 18m (in a single scan) and right at a particular inspection quadrant of the pipeline. Anyone may inspect a pipeline thanks to the handheld scanners’ distinctive self-positioning and adaptive reference capabilities. It just needs to get specialized training on your suitable 3D scanner & software; prior metrology knowledge or in-depth instruction on a variety of measuring methodologies are not necessary.
Regardless of human skill, 3D scanners employ optical technology to provide findings that are exceptionally precise, consistent, and trustworthy. With a reliable 3D scanner, you can take measurements up to 1,500,000 times every second with an accuracy of 0.05 millimeters and 0.1 millimeters resolution.
6 Integration of software with scanning
6.1 Corrosion
“Pipecheck” software carries a potential to assess internal and exterior corrosion so that provide a comprehensive 3D image of damage for more thorough, in-depth studies. This is made possible by UT or interior 3D scanning if it is feasible. As a result, all corroded regions may be captured in high resolution, and scanning performance for microscopic characteristics like pitting is increased.
The “Corrosion Analysis” feature of the program enables several automatic instructions that significantly reduce the labor of technicians. It contains a feature that uses actual pipe geometry for detection. It provides the ability to apply interaction rules automatically. Calculations of the expected burst pressure may be materialized. It provides improved simulated pit gauge functionality close to welds and barriers. These are all very important for pipeline corrosion inspection.
6.2 Mechanical Damage (Denting)
Key pipeline inspection features like the automated identification related to extreme depth, which might be hard to identify with conventional measuring techniques such as pit gauges & pipe calipers, are provided by Pipecheck.
The “Dent Analysis” feature of the program enables several automatic instructions that significantly lessen the labor of technicians. Automatic maximum depth detection is provided. With the use of pipe calipers and a straight edge, it provides depth measurement. It can conduct strain-based analyses.
It guarantees there will be a shoulder portion. Of them all, ASME Compliant: B31.8R, Strain Analysis, is the most significant.
6.3 Wrinkle Analysis
The wrinkle analysis module is designed to determine the wavelength, circumferential extent, diameter restriction, improving the accuracy of pipeline inspection studies and reporting. This enables quick and independent 360° measurements as well as the simultaneous scanning of several wrinkles in a single capture.
The “Wrinkle Analysis” feature of the program enables several automatic instructions that significantly reduce the labor of technicians. It provides a study of Wavelength and the depth of deformations from crest to trough. It serves as a measure of circumference. It oversees the limit on diameter.
7 NDT 3D scanning Procedure
Step One: Initial Inspection
Several places of corrosion beneath the pipe connections are discovered during the first visual assessment. CUS (Corrosion under supports), as the name implies, is corrosion that develops at the point where a metal component meets the support it is receiving. It is common for the liquids to get trapped in support sites like clamps and brackets, which may lead to corrosion. The production of pits and other types of corrosion damage are possible as a consequence of this sort of localized corrosion.
Figure 4 Initial Inspection
Step Two: Cleaning and Pipe Shot Blasting
Following the first examination, it is agreed that a 3D scanner would be needed to conduct more in-depth research on corrosion. The surface needed to be cleaned and stripped of all oil, corrosion, and scale in order to be ready for scanning.
Shot blasting is a kind of abrasive and mechanical cleaning that is generally used to protect the surface of an item, such as a pipeline, and to prepare it for coating or painting. Abrasive materials are pushed at the surface of the metal part under very high pressure during the procedure. Shot blasting strengthens, polishes, and cleans the metal. Additionally, before using any coating, any flaws may be found and fixed by the asset owner or an NDT service provider.
Step Three: Performing the 3D Scan
Target Acquisition and Surface Acquisition are the two major operational concepts for scanning in “Pipecheck.” In terms of precision, the target acquisition process is crucial. The white targets are essential to the precision of the scan since they provide the scanner with a constant sense of its location.
The lasers are used to do the surface acquisition. The surface bends the lasers. In addition, the cameras capture the bending to produce the surface.
The Pipecheck arrow, which may also be deployed to match the pipe to other forms of data like ILI and UT, enables the scan to be correctly aligned. To accurately reference it, it is often positioned at the 12 o’clock position, next to a girth weld. It needs to be positioned perpendicular to the pipe axis.
Figure 5 performing 3D scan
Step Four: Data Analysis
Coding Choice
There are two options available: Depth Analysis Only or ASME B31G.
Sflow Variables and Parameters
The B31G, Modified B31G, and Effective Area standards employ flow stress to determine the bursting pressure. It is crucial to choose the proper specifications right away since the inspection and Sflow parameters will eventually be shown in the report. Before doing any study, the asset owner should submit the Specified Minimum Yield Strength (SMYS), Pipe Material Grade, and Design Factor.
Parameters for pressure
The primary pressure metric used to evaluate the burst pressure is the MAOP (Maximum Allowable Operating Pressure). As per “The Barlows Equation,” the program automatically calculates this. Another significant number that the asset owner must provide to the inspection team is the MOP (Max. Operating Pressure).
Interactional Conditions
Corrosion characteristics are detected and documented for corroded regions throughout the analysis procedure. Depending on the circumstances of the interaction, their sizes and forms will change.
Circumferential and Axial Criteria
Various interaction rules may be used to combine adjacent corroded regions into a single feature (cluster).
In accordance with the chosen Interaction technique, the boundaries of each corroded region are set at the depth specified by the corroded area criteria.
Delimited regions are increased by a factor of 1/2 of the axial and circumferential criteria (red lines).
Two larger regions are joined together if they cross over one another. If two expanded regions do not overlap, the corroded areas must be separated from one another by a distance that is at least equal to the sum of the axial and circumferential requirements.
Figure 6 3D Scanner
Step Five: Results
Here, the final collection of data is produced. The Pipecheck program may also display a defect’s axial location, anomaly class, effective area, circumferential placement, and circumferential breadth. The customer receives a report when all of this data has been collected and entered into an excel document.
8 Conclusion
For inspection related to the corrosion, wrinkle, and mechanical impairment and damage of the pipelines, the portable 3D scanner technology is the logical advancement over conventional NDT methods. The most recent developments in this technology offer better quality of data thanks to a special dynamic referencing system and a useful reference surface. Without a doubt, this technology is the most suitable and a robust way to identify the issues related to the pipelines. It will continue to ameliorate the industrial regimes in the long run.
9 References
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- Kus, E. Unver, A. Taylor, A comparative study of 3D scanning in engineering, product and transport design and fashion design education, Comput. Appl. Eng. Educ. 17 (3) (2009 Sep) 263–271.
- Javaid, A. Haleem, L. Kumar, Current status and applications of 3D scanning in dentistry, Clin. Epidemiol. Global Health 7 (2) (2019 Jun 1) 228–233.
- ASME B31G-2009, Manual for Determining the Remaining Strength of Corroded Pipelines, American Society of Mechanical Engineer, 2009.
- https://www.wevolver.com/article/the-power-of-3d-scanning-for-corrosion-and-mechanical-damage-assessment (Figure 1)
- https://www.creaform3d.com/en/ndt-solutions/ndt-pipeline-inspection-oil-and-gas-industry (Figure2,3,6)
- https://proqc.com/industries/pipelines/ (Figure 4)
- https://www.industrysearch.com.au/3d-laser-scanning-pipecheck-pipeline-integrity-assessment/p/140604 (Figure 5)
