Transforming Penstock Inspection with AR in Hydropower Plants
A major hydroelectric power plant faced a critical challenge of —----- How to efficiently inspect the decades-old penstock lines plagued by external corrosion without inaccuracies, time delays, and heavy manpower required by traditional methods like spot ultrasonic testing. These lengthy and large pipes that handle pressurized water from reservoirs to turbines, were installed decades ago and needed accurate corrosion evaluation to ensure their safe continued operation and reliability.
Traditional inspection methods such as manual ultrasonic testing, visual checks, Rebound hammer testing, Dye Penetrant Testing (DPT) etc proved to be manpower-intensive, time-consuming and prone to errors when dealing with such complex, large surfaces.
To accelerate and modernize the inspection process, the hydropower plant implemented a hybrid approach combining Augmented Reality Remote Visual Assistance with In-situ 3D laser scanning technology.
This transformative approach not only enhanced and accelerated the inspection process and its accuracy, but also reduced labor costs, safety risks, downtime, — while empowering on-site inspectors to arrive better prepared with the right instructions, tools and expert support for more efficient execution.
Traditionally, penstock inspection was dependent almost exclusively on visual examination by inspectors using ultrasonic thickness gauging. These methods were limited and not ideal:
With corroded penstock posing a serious risk to the hydraulic efficiency and structural integrity of the system, a scalable, modern data-rich, and expert-driven inspection model was urgently needed to reduce manual effort, enabling more accurate and faster assessments, and ensuring cost-effective, safe inspection and maintenance planning.
To overcome these challenges, an innovative hybrid inspection model was adopted:
On-site field technicians used AR Genie Remote Assist App on their AR-enabled smart devices such as iPad/Tablet to connect with the remote inspection experts in real-time. On the other hand, the inspector was able to visually view the technician’s viewport in real-time.
Through the AR interface & live video streaming :
Outcome : Instead of relying on isolated technician judgment, this remote collaboration between the inspection expert and on-site technician enabled faster decision-making for proper inspection preparation process, reduced expert travel costs, rework, errors, and inspection time.
Once the surface preparation was done, portable 3D laser scanners were used to capture high resolution images of the penstock surfaces. 3D laser scanning is a non-destructing-testing (NDT) technology which is used to accurately measure metal loss or geometrical deformations and surface defects with a very high accuracy. In this case, the 3D laser scanning method was used for mechanical damage, external corrosion, pipeovality and profiling.
Outcome : High-density, reliable inspection data without needing manual grid markings, gauges, and physical templates.
Although plants do have their traditional or modern tools and techniques such as borescopes, laser scanners, ultrasonic testers, AR remote visual assistance brings a highly effective additional level of efficiency, skill, and coordination that essentially enhances the workflow of inspection.
Here’s how AR makes a critical difference:
In the proper assessment of penstock corrosion, preparing a clean surface ( like sandblasting ) for clear inspection is important. If not done properly, the ultrasonic tool or scanner can give misleading results. Using Augmented Reality:
Main Benefit:
By visually inspecting and preparing the surface before the actual laser scanning, this approach minimizes errors and eliminates costly repeat scans or rework, ensuring that high-quality data is acquired on the first attempt.
Rather than scanning blindly the entire structure, Augmented Reality Remote Visual Inspection helps experts or inspectors to prioritize where to scan based on clear signs of mechanical impairment, excessive corrosion, or prior maintenance activities.
Main Benefit:
Smarter and faster inspections — saving operational costs, manpower, and time while ensuring critical issues are addressed with precision.
AR AR can help in real-time troubleshooting and training. For example, if a field technician or local site personnel staff faces any issues in using the inspection tools, calibration errors, surface reflectivity problems, interpreting the laser scanner’s live feedback — AR remote support provides immediate expert troubleshooting guidance without waiting for a specialist to arrive on-site.
Main Benefit:
Improving first-time right results, reducing downtime, and building a smarter, more self-reliant workforce.
Using AR, remote experts can review 3D scan results instantaneously after the scan, helping them to quickly validate the full coverage achieved. They can have remote technical video conference discussions to:
Main Benefit:
Facilitated faster reporting and decision-making as the results are available quickly and the teams need not to wait to find out the corrosion severity.
Conventional toolkits traditionally measure — but AR enhances how you utilize those tools to their optimum.
Using AR-driven remote assistance combined with 3D laser scanning, the hydro plant was able to:
The deployment of AR-supported remote visual inspection along with 3D laser scanning technology transformed penstock examination at the hydro power plant to a complete extent. Not only was structural reliability and safety heightened, but also a model of scalability was demonstrated for infrastructure inspection in energy and utility industries with similar aging asset issues.
While industries are looking to find a balance between operational efficiency, worker safety, and equipment longevity, implementing AR technology with advanced non-destructive testing solutions is proving to be not just an innovation—but a necessity.
