Failure of pipework in fuel tanks

  • Safety Flash
  • Published on 21 September 2017
  • Generated on 24 April 2025
  • IMCA SF 23/17
  • 2 minute read

Water ingress into a fuel tank was discovered to be from leaking pipework. 

What happened?

Water ingress was reported into a fuel tank from two seawater lines running through the tank.

Engineers investigating a high-level alarm on the fuel tank initially thought it was due to vessel movement. But upon inspection of the pipework, a leak was found on a sea water pipe approximately 150 mm outboard from the Pump Room bulkhead.

23175

What went wrong? What were the causes?

There was a hole of around 13mm diameter in the pipe, which had caused seawater leakage into the tank and thus, a rise in level. Fuel was transferred from this tank to the port side settling tank and shortly after starting the transfer, the port side fuel separator tripped out.

The 3rd engineer went to clean the strainer and quickly realised that a large amount of water was present in the system. A check on the settling tank drain confirmed that there was water present.

The cause was a failure of pipework installed on the vessel at build stage.

What lessons were learnt? What actions were taken?

  • Clarification of fuel tanks on vessels if pipework lengths run through tanks.

  • Inspection of pipework in tanks for integrity through visual and ultrasonic thickness baseline measurements.

On the IMCA website, entering corrosion into the safety flash webpage search bar generates around 60 results which Members may wish to check for themselves.

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