Published on 01-Nov-2023

Custom NDT Solutions for In-Service Wheel Rail Interface Testing

Custom NDT Solutions for In-Service Wheel Rail Interface Testing


As you watch a train pass by, you may count the rail cars carrying freight safely to its desired destination. Those in the rail transportation industry, however, know that the real action is in the wheels. The wheel rail interface is one of the most important components for a train’s operation. Its performance determines if the cargo will arrive on time, and regular inspection is necessary to ensure the integrity of this component. This article discusses why Phased Array Ultrasonic Testing (PAUT) and Eddy Current Testing (ECT) are critical for in-service wheel rail interface testing.

The transportation of valuable rail cargo depends on the reliability of the wheels they are sitting on. The enormous pressure that train wheels are constantly under means that they are susceptible to flaws. Thickness measurements must be performed routinely to make sure that the wheel can withstand this stress. But every time a wheelset is removed to be inspected, it increases the downtime for the railcar. The ability to address tight spaces in a fast-paced environment requires a Non-Destructive Testing (NDT) technique that can inspect a wheel rail interface with minimal downtime. That’s why custom NDT solutions for wheel rail interface testing are so important. These inspections can be done with either ultrasonic or eddy current testing methods, both of which can minimize downtime. Making sure the wheel rail interface is functioning at its highest level increases efficiency, protects property, and can even save lives.

The Need for Wheel Rail Interface Testing

NDT for the railway industry looks at several different components, including the strength of the rail itself. The rails are under constant pressure from the weight, strength, and speed of the train. Much of that pressure is centered on the wheels.

The flange on the wheel is critical for keeping it on the rail. Flanges must maintain a thickness level that helps prevent cracks and chips that can turn into huge problems. When the thickness decreases, damage can occur. The NDT technology used must measure both thickness and inspect for minute flaws on all of the irregular surfaces encountered within the wheel.

Regular inspections are vital and unavoidable (and indeed highly regulated). The number of required inspections can increase downtime. The key is to find an NDT solution that limits that downtime while maintaining the highest standards of efficacy and accuracy.

The Benefits of Custom NDT Solutions for Wheel Rail Interface Testing

The wheels on trains are bulky; they can be shaped irregularly and modern trains exist in complicated electromagnetic environments. Under these circumstances, an NDT solution often needs to be customized for the specific job in order to maximize its functionality. There are two primary types of NDT solutions for the wheel rail interface. Each of these solutions have different combinations of instruments, probes, scanners, and software. Finding the ones that are right for you are crucial to a successful wheel rail interface inspection.

Ultrasonic Testing

PAUT equipment is an ideal solution for the challenges of in-service wheel rail interface volumetric inspections due to its portability, affordability, and accuracy. When time is of the essence—as it often is—PAUT testing equipment gets the job done.

Though there are many different kinds, with different degrees of sophistication, advanced PAUT testing equipment offers significant benefits:

  • 2D Array focus technology
  • No need for interval or reverse detection
  • High performance
  • Rugged
  • Portable

Portability is important for wheel rail interface testing, especially in crowded trainyards or large lots. Being able to keep moving with equipment and test quickly as wheels come on and off can greatly limit downtime and increase efficiency getting trains back in service. Check out this application note on how to access proactive train axle integrity insights with phased array ultrasonic testing.

Eddy Current Testing

For surface and subsurface flaw detection, ECT tools are perfect for the unusual conditions of the railyard or shop. Handheld eddy current testing devices are ergonomic, rugged, and have a long battery life that lets technicians quickly inspect multiple wheelsets.

Another benefit of eddy current testing is that the work can be done quickly, with remote data acquisition units. The ability to have fully automatic positioning and retracting makes for a much smoother process.

Additionally, a highly flexible eddy current array probe is extremely easy to use and requires no interval or reverse detection. All you have to do is start from the front or the rear of the wheel and make one pass. This simplifies and improves the efficiency of the entire system.

Finding the NDT Solution that is Right for You

When determining which NDT solution for wheel rail interface testing is right for your needs, consider this: With the proper equipment, the detection time for a single wheelset can be under 60 seconds—that’s less than a minute to obtain a 2D or 3D rendering of thickness and defects, and enough time to make repairs avoiding lengthy downtime.

Not only that, but many advanced systems use data mining techniques to enable an educated estimation of flaws. The accumulated information helps technicians understand what needs to be repaired right away and what can be scheduled, allowing for a smarter use of resources.

Custom NDT solutions for wheel rail interface testing provides many benefits. These include:

  • Precise detection
  • High efficiency
  • Excellent stability
  • Time and labor savings
  • Strong adaptability
  • Intelligent decision making

Wheel rail interfaces are under a lot of pressure, but with the right custom NDT solution, technicians tasked with keeping them running don’t have to be. Eddyfi Technologies offers advanced NDT solutions for wheel rail interface volumetric inspections and so much more. Contact us to discuss your inspection requirements and stay Beyond Current.

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Application Notes