NItal Etched Macro

3 cases · 4 images

Crevice Corrosion in a Subsea System — Aspect Before Analysis

Macrography of a section longitudinal to the pipe and transverse to the weld. The thickness of the pipe is 12,7 mm (1/2") and it was welded in 6 passes, the root pass, one fill pass and four cap passes.
855
ML00153 / Jan.2019
X52 in a Tubular Structure
M - CMn SteelP - Seamless PipeAp - StructureCd - Qualified
Cm - NItal Etched MacroDf - Welded Joint
ML00066 / May.2017
GMAW Welded Joint in 9%Ni Alloy Steel
M - Nickel Alloy SteelP - Welded Testpiece for QualificationAp - PipelineCd - Welding
Cm - NItal Etched MacroDf - Welded Joint
The longitudinal section of the 1/2" thick pipe close to the washout position shows that the external tool marks are like notches that are corroded and cracks are iniciating from the corroded regions.  The top of the figure presents the external pipe surface and the bottom of the figure presents the internal pipe surface, with a green coating and the rusted washout.
154
ML00068 / Sep.2020
Corrosion Fatigue of a 5" Drill Pipe
M - Low Alloy Medium Carbon QTP - Seamless PipeAp - O&G Well DrillingCd - Corrosion Fatigue
Cm - NItal Etched MacroDf - Longitudinal Section

More from these cases

ML00068 — Corrosion Fatigue of a 5" Drill PipeM - Low Alloy Medium Carbon QTP - Seamless PipeAp - O&G Well DrillingCd - Corrosion Fatigue
Macrography of the longitudinal section of the pipe presenting multiple cracks from the tool marks.
122
ML00068 / Sep.2020
Corrosion Fatigue of a 5" Drill Pipe
M - Low Alloy Medium Carbon QTP - Seamless PipeAp - O&G Well DrillingCd - Corrosion Fatigue
Cm - NItal Etched MacroDf - Cracks Transverse to the Surface