Corrosion of Flowline

Description of Incident

An impermeable insulation was fitted to a flowline as a coating repair.

This repair trapped moisture underneath it leading to corrosion.

Findings:

• The assessment that identified the coating repair as suitable did not identify that the flowlines known movement would compromise the coatings seal once applied. This resulted in the seal being ineffective allowing moisture in.
• The visual inspections post application did not detect the faulty seal; this was influenced by site ergonomics.

Good Practice Guidance

• Risk assess known and future site conditions and use this to inform risk-based inspection and repair strategies
• Always ensure the correct insulation is used for the correct repair and that it is fitted correctly