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A known rail defect left on a 52-week replacement window

Porthkerry, Vale of Glamorgan line, Wales · 2 October 2014

A rail defect was found two months before the derailment, but the standards then in force did not treat it as urgent, so replacement was scheduled within 52 weeks. The rail failed first.

What happened

At 02:30 on 2 October 2014, the last two wagons of a loaded coal train derailed at Porthkerry, between Barry and Rhoose, when the track beneath them collapsed.

No one was injured.

What the investigation found

  • A section of the left-hand rail failed because of a metallurgical defect from impurities present since manufacture. The rail had been installed at Porthkerry in 2008 after use elsewhere.
  • The defect was found on 30 July 2014 during an inspection for a different type of rail defect. Standards did not require urgent attention, so 52 weeks were allowed for replacement.
  • Visual inspections intended for this defect type had not been carried out, regular inspections had not found it, and staff did not identify that the rail needed urgent replacement.

Timeline

  1. 2008Rail, previously used elsewhere, installed at Porthkerry.
  2. 30 Jul 2014Defect found during an inspection for a different defect type; 52-week replacement allowed.
  3. 2 Oct 2014, 02:30Rail fails beneath the train; last two wagons derail.
  4. 6 Aug 2015RAIB publishes report 10/2015 with three recommendations.

Where Ralliyo fits

The evidence below is the kind Ralliyo records and keeps together. It shows how the capabilities map to the findings, not a claim about what would have happened.

Observation with priority and trendRail surface anomalyA recorded rail defect stays open on the asset with its priority, evidence image and every later inspection of the same rail, rather than sitting only in a work queue.
Maintenance loopThe defect links to its maintenance item and due date; the observation closes only after a post-maintenance inspection verifies the repair.
Re-assessment on new evidenceEach new inspection of the same rail is compared with the last, so a change in appearance prompts an engineer to revisit the severity.
Limits. Internal rail defects need ultrasonic or other non-destructive testing. Ralliyo can hold those results and track the defect, but it cannot see inside the rail from photographs.

RAIB recommendations

  1. Improve methods for detecting this type of rail defect.
  2. Improve techniques for assessing its severity.
  3. Assess the risk from similar rail at other locations.