One of the most important mechanical systems on any train is its wheel interface. Wheels bear the lion’s share of the force experienced by a train in motion and, therefore, wheel-rail interfaces can become flawed after prolonged use. Ultrasonic testing and eddy current testing are two non-destructive methods which can identify cracks and corrosion in the surface material and structural material of rail and wheel interfaces. If faulty parts are not identified using NDT and replaced, dangerous risk levels can result and threaten the safety of cargo, crew and passengers.
The most important non-destructive test used to evaluate the working condition of wheel interfaces in rail vehicles is a thickness test. There is an issue of efficiency here, though, as removing every wheel on a rail vehicle, measuring it and restoring it would take an exceptionally long time. Non-destructive testing can be used instead to increase the speed of evaluation. Ultrasonic testing methods may be employed to reduce downtime when inspecting wheel-rail flaws.
How Does Ultrasonic Testing Work?
Non-destructive ultrasonic testing works using a transmitter and receiver. The transmitter broadcasts a wavelength through a test item and the receiver measures the time it took to get there. By knowing the length and speed of the wavelength used engineering crews can calculate the thickness of a component and determine if it’s still in working condition.
Changes in thickness in a rail wheel can result from applied force for an extended duration. Changes in thickness if left unattended can result in chips and cracks in rail wheels which poses a danger to all cargo, crew and passengers. If a damaged wheel-rail interface is not able to withstand the powerful forces that act upon it during transit trains can bounce and become derailed. Ultrasonic testing can prevent this by identifying when changes in a wheel-rail component’s thickness have occurred. In these instances, a replacement part can be fitted to ensure safety is maintained.
Eddy Current Testing
Given the complex electromagnetic environment in wheel-rail interfaces, surface and subsurface components may experience fault which can lead to serious risk; as mentioned above. Eddy current testing can be used to identify surface and subsurface inconsistencies resulting from electromagnetic interference. Eddy current testing uses induction as its primary function. A current is passed through a non-resistant material by a transmitter and is measured for consistency. If measurement of the current by a receiver demonstrates structural inconsistencies, the part can be removed and replaced accordingly.
Buy Non-Destructive Testing Equipment
If your railroad operation is considering handling regulated non-destructive testing of wheel-rail interfaces, you will assuredly need equipment. You want to keep your trains safe and in good condition for the sake of safety and risk reduction. You need to make sure that they can withstand large forces during the transport of goods or passengers. You are probably wondering, ‘Where can I buy NDT equipment?’
NDT Australia supplies both ultrasonic and eddy current testing machines across the nation. Contact us via our contact form or on (02) 9524 0558 to make an enquiry about any of the NDT equipment we have listed on our website. We are available from 7:30am to 4:00pm Monday to Friday.
