Atlas

3 cases · 3 images

Crevice Corrosion in a Subsea System — Aspect Before Analysis

Internal surface detail of the 3 1/2" pipe, cut in a longitudinal section (transverse to the weld), presenting a localized corrosion at the margin of the welded joint (Keller etched), in the root.  The pipeline was assembled with pipes manufactured in two different aluminum alloys, AA 3003 (top of the figure) and AA 6063 (bottom of the figure), and the localized corrosion occurred at the fusion line of the 6063 pipe.
1296
ML00059 / Feb.2018
Intergranular Corrosion of Aluminum Piping
M - Aluminum ManganeseP - Welded JointAp - Chemical IndustryCd - Intergranular Corrosion
Cm - Surface AspectDf - Welded Joint
Macrography of the pipe to fitting welded joint, in a region where the thickness loss is almost uniform. The pipe is in the left of the figure and the elbow is in the right, with a general thinning (average of 2 mm, considering that the original thickness was 3.7 mm), and a slightly more intense thickness loss at the weld metal near the elbow side.
183
ML00065 / May.2017
Erosion Corrosion of Monel Piping
M - NiCu AlloyP - Seamless PipeAp - Chemical IndustryCd - Erosion Corrosion
Cm - Kalling Etched MacroDf - Welded Joint
External aspect of the 8" diameter pipe that suffered localized thinning and leakage associated to the welded regions.  The vertical weld is the pipe seam and the horizontal weld is the circunferential butt weld.
142
ML00005 / Apr.2017
Environmental Hydrogen Damage in Ti Pipe
M - Unalloyed TitaniumP - Longitudinal Seam Welded PipeAp - PipingCd - Hydride Formation
Cm - Aspect Before AnalysisDf - Welded Joint