Damage

1 case · 8 images

Crevice Corrosion in a Subsea System — Aspect Before Analysis

Damage — sub-branches

Aspect of a transverse section of the 4" pipe showing the barnacles adhered to the internal pipe surface, and the leakage position (in the top of the figure).  It is possible to see that the deposits are attached all throught the internal pipe perimeter but the damage is localized.  The damage morphology suggests it is a crack, or a welding defect, but the microstructural analysis indicated that the damage is a galvanic effect at the autogenous seam weld.
1135
ML00140 / May.2019
Preferential Corrosion of Pipe Seam Weld
M - Low Carbon SteelP - Longitudinal Seam Welded PipeAp - ShipCd - Preferential Dissolution
Cm - Longitudinal Section AspectDf - Localized Corrosion

More from these cases

ML00140 — Preferential Corrosion of Pipe Seam WeldM - Low Carbon SteelP - Longitudinal Seam Welded PipeAp - ShipCd - Preferential Dissolution
Detail of the transverse section of the 4" pipe at the longitudinal seam weld evidencing the leakage position.  The damage appears as a through wall opening.  The pipe thickness is 8 mm and there are no evidences of general corrosion (the SCH 80 corresponds to 8.6 mm) or pitting at the internal surface.
100
ML00140 / May.2019
Preferential Corrosion of Pipe Seam Weld
M - Low Carbon SteelP - Longitudinal Seam Welded PipeAp - ShipCd - Preferential Dissolution
Cm - Transverse Section AspectDf - Leakage
ML00140 / May.2019
Preferential Corrosion of Pipe Seam Weld
M - Low Carbon SteelP - Longitudinal Seam Welded PipeAp - ShipCd - Preferential Dissolution
Cm - Transverse Section AspectDf - Transverse Section
ML00140 / May.2019
Preferential Corrosion of Pipe Seam Weld
M - Low Carbon SteelP - Longitudinal Seam Welded PipeAp - ShipCd - Preferential Dissolution
Cm - Transverse Section AspectDf - Transverse Section
ML00140 / May.2019
Preferential Corrosion of Pipe Seam Weld
M - Low Carbon SteelP - Longitudinal Seam Welded PipeAp - ShipCd - Preferential Dissolution
Cm - Transverse Section AspectDf - Transverse Section
ML00140 / May.2019
Preferential Corrosion of Pipe Seam Weld
M - Low Carbon SteelP - Longitudinal Seam Welded PipeAp - ShipCd - Preferential Dissolution
Cm - Transverse Section AspectDf - Localized Corrosion

+2 more from this case →