Digitizing switch points for optimization of maintenance
A major responsibility for owners of railway infrastructure is to ensure high uptime. Growing traffic rates in combination with demands for higher speed and heavier rolling stock is causing increasing wear on the infrastructure, and owners are fighting a never-ending battle to keep up with these requirements. While also being subject to continuous demands for savings pushes owners as well as contractors to find innovative ways to deal with excessive and cumbersome tasks in order to enable more effective maintenance of the railway.
According to the statistics, rail switches take up around 20% of the total yearly maintenance budget and around 25% of the renewal budget in the railway industry. This amount is partly because of the demand for frequent inspections on the electrified switch points. Switches are the most vulnerable part of the railway, as moving parts and intense curves are exposed to more wear and tear as well as operating failures. This make switches one of the biggest sinners in the terms of downtime and delays in railway traffic. These disruptions and delays of train operations are very costly and inconvenient for operators as well as for passengers.
Condition monitoring of railway switches
A handful of companies provide solutions that monitor railway switches. These systems mostly measure the amount of energy used by the switch motor. Values are then compared to an earlier set reference value derived from the switch in question when in an optimal state. Hereby it’s possible, at least to some extent, to show the switch degradation state, and some systems even vaguely predict a breakdown. However, monitoring the energy consumption profile of the switch motor gives only a limited and indirect indication of the current system health.
Railmonitor’s switch monitoring system takes a different approach and installs sensors directly onto the switch. This setup gives a real-time overview of the position of different components in the switch. The system monitors the position of the switch rail as well as the gap between the stock and switch rail, and lastly, rail temperature is monitored. We are currently working on implementing other measurements for a complete replication of the regular inspection.
Statistics for trend analysis
The system provides real-time overview of the switch, showing the current switch position and gap between the stock and switch rail. Additionally, it stores statistics for each individual switch, which include the duration of the switch, the speed that the switch rail moves at, the gap between the switch and stock rail and the rail temperature.
Furthermore, the system also stores information about how many times a switch has occurred, and how outer limits of the switch rail develop.
Gathering this data for each individual switch makes the system able to provide trend statistics for all the different measurement points. The objective of these statistics is to offer insight into the switch and being able to plan maintenance according to actual needs and hereby transition into a condition-based maintenance process. Consequently, being able to monitor directly on the switch itself, could provide valuable information, that monitoring of the power would not be able to show.
The solution is very flexible, and dependent on the requirements for the specific switch, the sensors can be mounted in different positions of the switch.
Visualization of data
The information gathered by the system is integrated into Railmonitor’s software solution, which purpose is to present the data in an easy and accessible form for anyone this system would be relevant for. Additionally, the system can be set up to deliver warnings when any critical tendencies are occurring.
The goal of the sensors is to provide infrastructure owners and operators with an understanding of problematic switches and prevent downtime.
The Railmonitor switch monitoring system has been tested in a real environment for several months. The system is running smoothly without any downtime and provides reliable values in real-time. Further validation is about to take place on several other locations subject to high traffic load. Problematic as well as normal-functioning switches will be included in these next projects.
Read more about Railmonitor on their website