DTK - Rail Infrastructure Measuring and Monitoring

Deutzer Technische Kohle (DTK) is a supplier of rail infrastructure measuring and monitoring services. Established in 1991, the company is well-known to public transport operators. Its customers can rely on the experience gained in more than 330 measurement and consulting services, performed in more than 17 countries.

DTK carries out its measurements in regular service and under normal traffic conditions. Thus the measured values show the infrastructure's real condition.

The company's range of rail infrastructure measuring and monitoring services and systems includes:

• Overhead line monitoring
• Track measurements
• Pantograph tests
• Optimisation of wheel and rail interactions
• Driving comfort measurements
• Third rail measurements
• Clearance measurements
• Surveying of handicapped accessible platforms
• Synchronous video and sound recording

Overhead-line monitoring

DTK's overhead-line monitoring system measures the stagger and height of the overhead wire, the shocks between overhead wire and contact strips, and the strength of electrical current and its direction for each contact strip.

Overhead wire voltage, contact force and contact resistance, rise and fall of the wire, wire wear, geographical coordinates, and interaction between pantograph, bogie and track can also be measured.

Track measurement

The following parameters can be measured by DTK's track measurement system during normal traffic running and under normal load conditions:

• Gauge
• Width of each groove – left and right
• Depth of each groove – left and right
• Wear of the rails (rail contour and bend of flanks)
• Curve radius
• Longitudinal height and lateral height
• Torsion
• Smooth and quiet run of the wheels
• Shocks between wheels and rails
• Coordinates
• Ramps
• Speed

Pantograph inspection

Pantographs have to ensure a continuous current transfer between overhead wire and vehicle. DTK's inspections allow for the necessary adjustments to meet this condition.

Train driving-comfort inspection

DTK can inspect and measure driving comfort in trains. Also under development is a monitoring system for flats on train wheels.

Train clearance measurement

The clearance measurement system finds all objects which enter the clearance space of rail vehicles or are within 8m of the rail axle.

Third-rail measurement

DTK's third-rail measurement system measures:

• Lateral position and height of the third rail
• Shocks between third rail and contact shoe
• Strength of electrical current and its direction for each contact shoe
• Current rail voltage
• Contact force and contact resistance
• Rise and fall of the third rail
• Third rail wear
• Coordinates
• Interaction between contact shoe and current rail

Train wheel and rail testing

Testing of the interaction between wheel and rail (sine run) and optimisation of wheel and rail profiles is also carried out by DTK.

Thickness-measurement for trolleybus overhead wires

Unlike overhead lines for tramways, whose contact strips only draw the current from underneath the wire, trolleybus overhead wires also wear out sideways.

DTK is currently developing an innovative type of measuring equipment which allows for the calculation of the wire's remaining cross-section. Two lasers and two cameras, which record the wire's contour, make this possible.

To perform the monitoring, DTK's measuring device is fitted to a service vehicle, which travels at approximately 20km/h. The wire contours are recorded at a rate of 200 measurements per second, or approximately every 30mm.

After-examination service and reports

Immediately after each examination clients receive:

• Test data, video films and audio files
• DTK software on DVD
• Instruction in the use of the analysis software (DTK also provides additional software training if requested)

Approximately four weeks after measurement, clients will get an investigation report.

Platform measurement system

The DTK system for platform measurement makes it possible to check the specified dimensions of disabled-access platforms. This includes the distance between the platform edge and the track (either left-hand or right-hand depending on which side of the train the platform is located), and the height of the platform edge in relation to the track.

So far employees of public transport have carried out random checks manually with a ruler, e.g. every 5m. The DTK system instead measures these values in a comfortable contactless way every 5cm (20 records per m). To perform this measurement, DT installs two laser/camera units on a sliding carriage, whose lateral guiding device is fixed to the vehicle's front bumper.

Infrared thermography system

DTK infrared thermal imaging systems make it possible to check the temperature at the contact point between overhead wire and contact strips.

• 60 measurements per s
• Accuracy of 0.17°C

This system is useful in all cases where energy can be transformed into heat as a result of an insufficient electric contact - e.g. energy recovery systems, control boxes and third-rail connections - or in order to control brake pads.