RPI   RailProf Instruments BV | Kedichem | The Netherlands



  • Measuring length: 1,000 mm in accordance with the EN standards for weld geometry;
  • Sampling interval 5 mm.
  • Transducers: eddy current.
  • Both vertical and lateral rail geometry are measured.
  • The vertical sensor is positioned 35 mm from the gauge face.
  • The lateral sensor is measuring the gauge face at 20 mm below the top of the rail.

The present RAILPROF configuration is controlled by a Windows Phone running on Windows 10.

On the basis of research at TU Delft, in cooperation with the Dutch Infra Provider ProRail, force-based standards have been developed. The standards are expressed in terms of a quality index QI, which is directly related to the first derivative of the measured vertical rail geometry.

Vertical and lateral geometry are measured simultaneously. The measuring results are automatically sent to the Smart Phone, which carries out all the calculations like filtering and computing the first derivative of the vertical geometry, in accordance with the force-based weld standards of ProRail.

Due to the additional speed classes in the lower speed range the standards are also applicable to metro and tram networks. The RAILPROF will be kept awake as long as the operator is working in the measuring menu on the Smart Phone, whereas otherwise the RAILPROF is switches off after 10 minutes of not being used.


Railprof Instruments

Michiel van Loonstaat 23a

4247 ES Kedichem

Tel: +31 183564924

Email: info@railprof.com

Esveld Consulting Services is partner of Railprof Instruments

Training at KORAIL



Templates can be created for each measuring job via the Templates menu. The values of the active template are used when the measuring process is started. After tapping the command measure the values of the template are shown and can be altered.

If the weld is measured again or a new weld is measured the previous values are kept.


Glued Insulated Joints

For Glued Insulated Joints (GIJ) a special feature is available to clip out the part between the rail ends at the joint. The eddy current transducer sees this area as a large deviation. When the correction is set to 'Yes', the central 10 mm of the measurement is removed and replaced by values linearly interpolated between the measured values at both ends.


The Microsoft Lumia smartphone facilitates to send stored measurement files directly by email via Outlook. Files in the project directory can be selected and added as attachment.

As an alternative to email, files can be stored and synchronized via Microsoft's cloud service OneDrive.


  • Checking and acceptance of flash butt welds, thermit welds and glued insulated joints;
  • Positioning of rails before welding;
  • Production of glued insulated joints;
  • Assessment of rail corrugation;
  • Monitoring progress of grinding process;
  • Acceptance of grinding work;
  • Acceptance of rails for longitudinal geometry, including straightness of rail ends.


Special Windows based desktop software is provided for viewing, editing, printing and presentation of the measurement results, as illustrated in the screen shots below.

Example of Windows software to view measured profiles.

Example of a print preview.

Example of short wave irregularities (corrugation) to control grinding.

Example of comparing two measurements.

The desktop software offers the possibility to select records on the basis of the quality index QI. Via the find icon a screen is opened in which a choice can be made for QI Top, QI Hor, or both. The selection value is default 1.00, but the user can assign any other value. After OK the screen at the bottom left shows just the selected records, which can be moved now.

The software offers printing facilities to generate one integrated report for a series of measurements. In the above example the reports for Top Assessment are selected and can be printed as one pdf file.

To facilitate German grinding standards a special menu was added to the desktop software. In the wavebands 1-3 cm, 3-10 cm and 10-30 cm the percentage of exceedance of the standard is presented. The standards can be set per waveband as the admissible displacement in mm. Furthermore, the following grinding indices are produced: GA = Grinding Amplitude,

GG = Average Wavelength, GSD = Average Grinding Depth.


  1. Weight: less than 7 kg;
  2. Length: 116 cm;
  3. Microsoft Windows Phone, with Windows 10:
          - Wireless communication via Bluetooth to control measurements and data transfer;
          - Data analysis, such as filtering and computing of QI;
  4. Measuring length: 1,000 mm in accordance with the EN standards for weld geometry; sampling interval 5 mm;
  5. Measuring time: about  10 sec;
  6. Data transfer to Smart Phone and analysis: about 6 sec;
  7. Data storage: unlimited on Smart Phone internal memory, Secure Digital (SD) card, or in the Cloud;
  8. Data transfer to desktop PC via mobile network, wifi, or wired synchronization;
  9. Presentation of measurements on desktop PC via Windows menu. Easy generation of reports in pdf format;
  10. Accuracy:
         a. High accuracy at ambient temperatures between - 5 ºC and + 40 ºC;
         b. Vertical geometry: +/- 0.020 mm;
         c. Lateral geometry: +/- 0.050 mm;
         d. Inclination associated with QI: +/- 5 %;
  11. Measuring principle transducers: eddy current. The results are not influenced by moisture, rust, dirt and the real metal surface is measured;
  12. Bottom of RAILPROF is resistant to temperatures up to 150 ºC;
  13. Shipping information:
         a. Total weight of flight case, RAILPROF, PDA and carton protection box: ± 19 kg;
         b. Dimensions: approximately 137 x 43 x 17.5 cm.

RPI - Michiel van Loonstraat 23a, NL-4247ES Kedichem

email: info@railprof.com - tel: +31 183564924