Benefits of Automated Corrosion Mapping, TOFD and Phased Array Scan Technology

Corrosion mapping is a mainstay of NDT. Semi-autonomous delivery platforms are widely used to bring the technology to multiple assets and the data returned is globally accepted to ensure organisations meet their legal testing requirements. 

Traditional corrosion mapping equipment utilises data points ranging anywhere between 3 – 5mm. This was, until recently, considered the optimal way to shorten the testing window, reduce asset downtime and, ultimately, increase productivity. Adding modular Phased Array UT technology and TOFD capability into the testing mix dramatically upscales the testing process.  

The TOFD/Phased Array UT Advantage 

There are many benefits of using a combination of both technologies when mapping for corrosion. These include: 

• A far higher resolution, with 1mm x 1mm as standard 
• Increases the process speed – is around 10 times faster than traditional corrosion mapping 
• Increases the probability of flaw detection 

This improves the whole maintenance process. Not only does it reduce the risk of unexpected breakdown and repair, but it allows for more productive planning. The more that’s known about the condition of an asset, the easier it becomes to schedule necessary offline work periods, combining relevant repairs and shortening downtime. 

The issue has been how to bring both technologies to any ferrous surface. This NDT is used across a wide range of industries. Critical assets that need to be tested in this way include:  

• Storage tanks 
• Pipelines 
• Spheres 
• Marine vessels 
• Pressure vessels 

Until now, there hasn’t been a truly modular solution that can deliver both TOFD and PAUT to any asset surface at the same time. The introduction of Accutrack to the market, an automated, steerable 3-axis scanner/tank crawler that can scan virtually any contoured ferrous surface is proving game-changing. 

As a platform, Accutrack can rotate in multi-axis’. This unique ability provides it with near-perfect wheel contact to both flat and curved surfaces. It boasts magnetic wheels and two powerful X-axis drive motors, providing excellent stability even when traversing weld seams.  

The operator can switch the truck into either 2-axis or 3-axis scanning mode during use, making it steerable throughout the complete corrosion mapping operation. This control is actioned remotely, via a small joystick or computer mouse.  

Accutrack is further customisable. The standard configuration is that of a 3-axis scanner. If required, this arm can be removed in order to carry out simple weld or line scans. Other options that can be added include: 

• Multi-probe weld inspection 
• A battery powered green laser line for weld tracking 
• Brings pulse echo, PAUT and TOFD to the asset surface 

This highly practical solution is suitable for high temperature environments (> 300F), can be powered by VAC or battery pack, is compatible with any UT system (with encoder input) and is lightweight. 

Accutrack is just one example of how technology is changing the face of NDT. Nexxis work with customers to determine the right solution for their testing needs – something that naturally changes over time. Such customised solutions are essential to streamline maintenance costs and increase that all-essential bottom line. Our commitment to advancing technology and solving your testing challenges is what makes our procurement model unique. 

 Contact us to find out more about Non-Destructive Testing or any of our other custom solutions, or request a quote online.