Corrosion behavior of bottom plates of a potable water storage tank

الملخص EN

This paper describes the investigation of a corrosion behavior of bottom Plates of a potable water storage tank.

The tank was internally inspected for the first time after fourteen years of service.

Paint blisters and rust spots were observed on the bottom plates.

Sand blasting and repainting the bottom plates and shell plates were to be used as a remedial work.

However, during the sand blasting, holes and deep pitting were observed on the bottom plates.

On-site visual inspection, magnetic flux leakage (MFL) inspection.

Ultrasonic testing (UT), and evaluation of the external catholic protection (CP) system were used in the failure analysis.

The failure is attributed to the ingress of water and its impoundment under the tank bottom along the periphery inside the ring wall and failure of water side epoxy coating.