CWRM · Continuously Welded Rail Monitor

See how rail force changes with temperature and time

CWRM measures longitudinal force and temperature at instrumented rail locations and brings the information together for track-management and maintenance decisions. Review trends, exceptions and equipment status across distributed sites.

The system calculates stress-free temperature (SFT), also known as rail-neutral temperature (RNT), from calibrated rail-force and temperature measurements. Measurement locations, configuration and reporting are defined around the railway and the decisions the information needs to support.

Measurement to decision

Follow the rail from field measurement to decision

  1. Measure at the rail

    Retrofitted sensors measure longitudinal rail force and temperature without rail cutting or sleeper replacement.

  2. Collect and communicate

    Track Processors communicate to a Field Processor, or a combined wired processor serves wired sites. Cellular service or country-approved radio to a High Site connects the field to central reporting.

  3. Process and present

    Review line and station status, time-based trends, exceptions and equipment-health information in OTT’s central reporting environment.

  4. Support engineering decisions

    Combine current conditions, historical trends and forecast scenarios to inform inspection, maintenance and track management.

CWRM provides decision-support information and does not replace the railway owner’s engineering standards, inspection responsibilities or operational controls.

Operator views

Move from line overview to site detail

The web interface provides a line-level view of instrumented locations, using status indicators to help identify where attention may be required. Move into an individual site to review measurements and equipment information.

CWRM overview listing eight sites with equipment status, rail temperatures, forces and SFT values.
CWRM line overview showing monitored sites and current status. Customer identifiers anonymised. Enlarge image: CWRM overview listing eight sites with equipment status, rail temperatures, forces and SFT values.

Available views can include rail force, temperature, calculated SFT/RNT information and equipment status such as battery level and communications signal. Role-specific presentation helps track and signalling teams focus on the information relevant to their responsibilities.

CWRM display for Site 08 showing rail measurements and equipment and track-status legends.
CWRM site view showing measurements and equipment status. Customer identifiers anonymised. Enlarge image: CWRM display for Site 08 showing rail measurements and equipment and track-status legends.

Trends and forecasting

Use trends to add context to a measurement

Examine how rail force and temperature change over selected periods. Review calculated SFT/RNT and equipment-health trends alongside field measurements, and export available data for further analysis. Historical context helps users investigate exceptions, compare locations and plan follow-up.

CWRM graph comparing temperature, rail force and SFT for two rail legs over time.
CWRM trends showing rail temperature, force and calculated SFT over time. Customer identifiers anonymised. Enlarge image: CWRM graph comparing temperature, rail force and SFT for two rail legs over time.

Explore forecast conditions

The forecasting module allows a user to enter an air-temperature range and forecast the track forces and SFT/RNT behaviour likely under those conditions. This provides a structured way to explore what-if scenarios and consider how the monitored railway may respond.

Forecast results support engineering assessment and are not a guarantee of future field conditions.

Reporting

Focus reporting on conditions that need attention

Scheduled reporting can distribute exception information at agreed times, including around shift or work-period starts. Reports organise exceptions by parameter, severity and location to support prioritised review.

We agree recipients, report configuration and distribution schedules for the application. An exception is information for assessment, not an automatic diagnosis or instruction to take a particular operational action.

Field configuration

Connect remote and distributed locations

CWRM supports wireless and wired field configurations. A Field Processor can serve multiple instrumented rail legs, while additional processors extend larger or multi-line applications.

Solar-powered Field Processors and battery-powered Track Processors can reduce dependence on local infrastructure. A plug-in cellular module is selected for the available network. Where direct cellular service is unavailable, country-approved long-range radio can relay data to a High Site with cellular connectivity.

Configuration depends on line layout, coverage, terrain, communications, access and maintenance requirements.

CWRM field equipment installed beside a rail line.
CWRM field installation with rail-mounted sensing and trackside equipment.

Retrofit installation

Add monitoring without rebuilding the track

CWRM sensing equipment attached to the existing rail.
CWRM rail-mounted sensor detail.

CWRM sensors attach to the existing rail, avoiding rail cutting and sleeper replacement. The compact, modular arrangement reduces installation work and allows components to be removed and reinstalled for maintenance or repositioning.

Replaceable processors, batteries, communications modules and sensing components support maintenance without treating the whole installation as a disposable unit. Track access, installation time and maintenance arrangements are confirmed for each site.

Technical overview

Website-level equipment information

CWRM technical overview
ParameterValue
Track temperature measurement range−25 to +75°C
Absolute temperature accuracyBetter than 1.5°C
Longitudinal force measurement range±4,000 kN
Force accuracy±2%
Selectable measurement intervals1, 2, 5 or 10 minutes
Selectable transmission intervals10, 20, 30 or 60 minutes
Track Processor battery lifeUp to four years for the applicable wireless configuration
Ingress protectionIP67 for applicable wireless equipment; IP68 for applicable wired equipment

These figures describe particular equipment configurations and are not universal site-performance guarantees. The project specification identifies equipment type, power arrangement, environment, measurement method and communications configuration.

Application review

Start with the railway section and the information you need

Tell us which line or locations you need to monitor, the decisions the information should support and any known power, communications or access constraints. If coverage is still being defined, we can work through the requirements with you.

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