Session: OAC-06-01 Operation and Maintenance of Pressure Vessels, Heat Exchangers, Piping and Supports

Paper Number: 60447

Start Time: Wednesday, July 14, 2021, 09:00 AM

60447 - Storage Tanks Settlement Assessment and Repair Optimization With the Presence of Bottom Plate Corrosion 

This paper discusses the assessment and repair methodology for the above-ground liquid storage tank. The subject tank experienced combined damages of edge settlement and corrosion at the bottom plate side. Rehabilitation of corroded bottom plates with the tank settlement presence has a significant effect on its structural stability and will lead to tank failure if it was not appropriately addressed. An interrelated damage mechanism requires a systematic analysis to identify the optimum repair methodology. The impacted tank was assessed, evaluated, and recommended to be repaired as per API-653 standard requirements. A specific repair procedure was proposed to tackle this failure. Feasibility and cost-effectiveness of the tank settlement, age, and structural durability were considered while repairing it. The current tank settlement condition repair was not required. However, due to the corrosion severity on the bottom plate at numerous locations, a specific repair procedure was proposed to repair and replace all defected portion. The repair procedure focuses on the tank critical zone because of its impact on the structure strength. An investigation was carried out to identify the cause of bottom plate corrosion and tank settlement. Two main causes of this tank failure are the absence of the tank drip plates and an ineffective cathodic protection system to prevent the tank bottom plate.    

Presenting Author: Meshal Al Saiari Saudi Aramco

Authors:

Meshal Al Saiari Saudi Aramco
Abdulaziz Moshaweh Saudi Aramco