A vapour tank vessel had suffered chloride induced corrosion that required an urgent repair without the use of hot work. The design of the repair required a defect model that would reflect complete section loss of the welded connections for a series of nozzles, and the vessel head circumferential weld.
The tank had the following specifications:
Structure | Vapour tank vessel |
Surface Preparation | Sa 2.5 |
Design Pressure | 340 kPa |
Design Temperature | 2200C |
Application Temperature | 50-1100C |
Design Life | 5 years |
Wrap Length | 6.5 m |
Vessel Diameter | 2.0 m |
Geometry | Vessel circumference, nozzles on dome end, lifting lugs on vessel side |
Corrosion Type | External |
Defect Details | 3mm loss on circumferential weld and 25mm through-wall defect on nozzle welds |