Rail Stress Management (RSM) plays a critical role in ensuring the safety and reliability of railway infrastructure. Thermal forces acting on continuously welded rails (CWR) can result in buckling during high temperatures or rail breaks in low temperatures, both which pose significant risk to safe train operations. Central to managing these risks is the measurement and maintenance of Stress-Free-Temperature (SFT). Reducing the risk of derailment as a result of track buckles or rail breaks is a priority for many railway companies and track engineers. For Indian Railway, the measurement of SFT is considered essential for reducing risks which could adversely affect the rail network.
Indian Railway commissioned Pandrol VERSE to provide a trial of its equipment for the measurement of rail stresses and determine stress free temperature (SFT) of LWR (long welded rail) / CWR (continuous welded rail) in one zone, to assess the performance of the equipment in different climatic conditions in a year.
The system was required to measure the stress-free temperature in digital format and record reproducible electronic forms to enable accurate maintenance decisions to be made. This enables determination of weaknesses in the track and any risks to be identified and managed.
Indian Railway is a large network with the majority of its track set on Broad Gauge comprising of UIC 60kg / IRS 52kg continuously welded rails laid on pre-stressed mono-block concrete sleepers on a stone crushed ballast bed.
In the past, measuring the SFT would have been a time-consuming, expensive and often unreliable process that involved cutting and welding the rail.
Pandrol Rahee Technologies was successful in securing a pilot project with Indian Railway to trial the use of the VERSE for North Eastern Railways (NER) at different climatic conditions. For this contract, Pandrol supplied the equipment and their engineers carried out the SFT measurement of 500km of track.
VERSE (Vertical Rail Stress Equipment) is an internationally accredited scientific instrument developed by Pandrol to non-destructively measure the stress-free temperature of continuously welded rail. It is an essential tool in modern Rail Stress Management programmes to ensure management of track buckling and rail break risk.
VERSE system is compact and easy to carry to the location where the measurement will be conducted. It eliminates the need to cut the rail, significantly reducing both time and cost.
It also measures the SFT directly from the rail installed in track and therefore requires no prior knowledge of the rail residual stress at the time of manufacture. All measured data is stored in the handheld computer available in the system and can be used by the railway network for future reference purposes.
Indian Railway was impressed with the accuracy of the VERSE equipment on the North Eastern Railways project, therefore Pandrol Rahee Technologies was invited to tenders for further projects to carry out rail stress management for other zonal railways within India.
Following this project completion, Pandrol Rahee Technologies successfully secured a further four projects in India to carry out rail stress management of 500km of track using the VERSE technology. Indian Railways has also earmarked budget for 150 nos. of such SFT measurement equipment’s to be procured and implemented across all its zonal railways.
First launched in 2002, VERSE has registered over 200,00 readings and is now in use in over 20 countries worldwide.
