Recoating: coating repair and replacement
We repair or replace damaged coating on buried pipes to restore the first barrier against corrosion and reduce the system’s current demand.
What it is
Recoating is the repair or replacement of the coating on a buried pipe. The pipe is excavated, the damaged coating is removed, the steel surface is prepared and a new coating, compatible with the existing one, is applied. The coating is the first barrier against corrosion; cathodic protection covers the defects that remain.
When it is needed
- When an inspection, such as the Direct Current Voltage Gradient (DCVG), identifies coating defects to repair.
- When the system needs more and more current because the coating has deteriorated.
- On sections with aged or disbonded coating, or with corrosion underneath.
- On weld joints and connections in new works or repairs.
How we do it
We locate the defect with the survey’s georeferencing and excavate until the pipe is exposed.
We remove the damaged coating and record the condition of the steel.
We prepare the surface according to the coating specification, usually by power tool cleaning.
We apply the new coating, compatible with the existing one and with the right material for each project, for example EasyCoat or anticorrosive tapes.
With liquid coatings, we check wet film thickness during application and dry film thickness at the end. We verify continuity with a holiday detector and backfill.
Equipment
- Manual and mechanical excavation equipment
- Power tool cleaning equipment
- Thermo-hygrometer, to check application conditions
- Wet and dry film thickness gauges
- Holiday detector
Deliverables
- Sheet for each repaired point: location, condition of the steel and coating, and before-and-after photos.
- Thickness and continuity test records.
- Final report in PDF.
- Instrument calibration certificates and personnel certifications.
Standards
ISO 21809-11 – ISO 21809-3 – ISO 8501-1 – SSPC-PA 2 – ASTM D4414 – NACE SP0274
Where we apply it
Pipelines – Industrial plants – Service stations and fuel depots