Tim Norman, principal materials consultant, Infrastructure Services, explores how metallurgical investigation and testing can help rail operators ensure they not only offer a safe rail service for passengers, but minimise future maintenance requirements too.
For many years, SOCOTEC has been providing a wide range of infrastructure materials testing services to the rail sector, with a network of laboratories across the UK dedicated to testing a host of substances, including metals, polymers and plastics, concrete and paint.
Metallurgical testing has historically been a crucial service across the rail sector, due to the breadth of information it provides regarding the long-term performance of track and train components, as well as structural elements of buildings.
Using the results of metallurgical analysis, operators can make key decisions that will help them to prevent component failures and minimise maintenance in the future. In doing so, they can streamline the cost of looking after assets while upholding the highest standards of safety for passengers and workers too.
The uses of metallurgy
Consultants will investigate and test components that are particularly worn, corroded, or broken to understand why they failed, so that steps can be taken to prevent the same issues happening in the future.
Testing is carried out on a wide range of metal items, including rail sections, fish plates, bolts and other ancillary parts of a rail track. On rolling stock, failed engineering components can be investigated, as can the breakdown of paint and other corrosion protection systems. Structures can also be investigated to determine the properties of the construction materials and their condition.
According to design, the failure of components and materials can occur for a number of reasons. For example, mechanical failure could be a result of deficiencies in the components design, the use of incorrect materials or overload in service.
Conducting the tests
There is a suite of tests that can be carried out by metallurgists on components from the rail industry. Regardless of the specific reason for undertaking metallurgical investigation, the studying of failures normally follows a set procedure so all evidence relating to the failure can be captured to determine the root cause.
The investigation can involve a number of techniques, including: detailed visual and low magnification examination, scanning electron microscopy and energy dispersive analysis. Metallography, chemical analysis and a suite of mechanical tests can also be used.
Once all of these tests have been carried out, consultants can then draw up an in-depth report, explaining the findings of the analysis to clients. If requested, the report can contain guidance and recommendations for corrective action, to help operators understand what they need to do to prevent a similar incident in the future.
Working with experts
Even the highest quality metal components wear or fail over time, requiring regular maintenance and repair to ensure they continue to offer optimum performance.
With in-depth metallurgical analysis of components - broken or otherwise - operators can access the information they need to minimise the risk of premature repairs in the future and to extend the lifetime of the assets in their care.
If you would like to find out more about SOCOTEC's metallurgical investigation and testing, contact the SOCOTEC team.