Vertical Split Head Detection - Eurailscout

Vertical Split Head Detection

The vertical split head (UIC 113, 213) type of defect can be ascribed mainly to metallurgical problems in the production of the rails. Steel production methods used in the past, such as the Thomas process generate a higher concentration of phosphorus, sulphur, nitrogen, manganese and hydrogen in the vertical plane of symmetry of the rail. If there are additional inclusions present in this level when the steel is produced, then this may lead to the formation of cracks in the rail over a length of up to 120 metres and thus to the breakage of the rail head over a great length. Thus, the vertical split head must be ranked as one of the most dangerous rail defects. In most cases it will inevitably result in a derailment. For  this  reason,  it  is  even  more  important  to  detect  the  vertical split head in its initial stage since this crack will increase steadily towards the running surface and the rail web with increasing train traffic volume and higher loads per axle. In the final phase of the crack growth, the rail head enlarges and it loses its strength and half the head completely brakes away over a length of many metres.
EURAILSCOUT  recently  deployed  a  patented  ultrasonic  testing technology on a worldwide exclusive basis which allows a reliable detection of a vertically split head in the initial stage. The testing method used delivers optimal test results irrespective of the wear condition  of  the  rails.  Our  clients,  for  example  from  Scandinavia and the Benelux (Belgium and Netherlands) countries, confirm our success.

Vertical split head in different growth phases up to the burst of the rail.