Pipe

6 cases · 53 images

Crevice Corrosion in a Subsea System — Aspect Before Analysis

Condition: Damage Capture method: Nital Etched Micrography by OM clear all

Pipe — sub-branches

Centrifugally Cast Pipe 3Longitudinal Seam Welded Pipe 4Seamless Pipe 8

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Micrography of the pipe transverse section presenting a granular microstructure.
147
VIEW
ML00140 / May.2019
Preferential Corrosion of Pipe Seam Weld
M - Low Carbon SteelP - Longitudinal Seam Welded PipeAp - ShipCd - Preferential Dissolution
Cm - Nital Etched Micrography by OMDf - Transverse Section
Micrography of a transverse section of the pipe, external diameter 33.4 mm schedule XXS, in the center of the 9.1 mm thickness. The structure is predominantly ferritic. Small amount of pearlite.
556
VIEW
ML00112 / Dec.2017
1" XXS Pipe Not Qualified For Low Temp
M - Low Carbon SteelP - Seamless PipeAp - RefineryCd - Not according to spec
Cm - Nital Etched Micrography by OMDf - Predominantly Ferritic
Micrography of a transverse section of the pipe, external diameter 26.7 mm, in the center of the 7.85mm thickness. Refined structure but not uniform. Ferrite and pearlite.
512
VIEW
ML00111 / Dec.2017
3/4" XXS Pipe Not Qualified for Low Temp
M - Low Carbon SteelP - Seamless PipeAp - RefineryCd - Not according to spec
Cm - Nital Etched Micrography by OMDf - Ferrite and Pearlite
Micrography of the welded joint fusion line presenting the liquation cracking. The weld metal is in the right side (bottom) and the forged connector heat affected zone is in the left side (top).
83
VIEW
ML00072 / Jan.2018
Liquation Cracks in a High Strength Joint
M - Low Alloy Medium Carbon QTP - Longitudinal Seam Welded PipeAp - O&G Well DrillingCd - Welding Defect
Cm - Nital Etched Micrography by OMDf - Cracking
The microstructure of the pipe, presented in a longitudinal section, is an uniform tempered martensite.
105
VIEW
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 Micrography by OMDf - Martensite
The micrography of a longitudinal section of the pipe, close to the internal surface, shows a general corrosion mechanism (with slow wall thickness loss), although the graphite/matrix interface is corroded preferentially.
569
VIEW
ML00034 / Apr.2017
45 Years Old Acquaduct Grey Cast Iron
M - Gray Cast ironP - Centrifugally Cast PipeAp - AcquaductCd - General Corrosion
Cm - Nital Etched Micrography by OMDf - Corrosion

More from these cases

ML00140 — Preferential Corrosion of Pipe Seam WeldM - Low Carbon SteelP - Longitudinal Seam Welded PipeAp - ShipCd - Preferential Dissolution
Micrography of the pipe transverse section presenting a predominatly ferritic-perlitic microstructure.
132
VIEW
ML00140 / May.2019
Preferential Corrosion of Pipe Seam Weld
M - Low Carbon SteelP - Longitudinal Seam Welded PipeAp - ShipCd - Preferential Dissolution
Cm - Nital Etched Micrography by OMDf - Ferrite and Pearlite
Micrographic detail of the predominatly ferritic-perlitic microstructure. Pipe transverse section.
95
VIEW
ML00140 / May.2019
Preferential Corrosion of Pipe Seam Weld
M - Low Carbon SteelP - Longitudinal Seam Welded PipeAp - ShipCd - Preferential Dissolution
Cm - Nital Etched Micrography by OMDf - Ferrite and Pearlite
Micrography of the pipe in the leakage area, showing the preferential corrosion in the center of the autogenous weld and oxides inside the crevice, that appearas as a cracking but that is only a localized anodic process.
66
VIEW
ML00140 / May.2019
Preferential Corrosion of Pipe Seam Weld
M - Low Carbon SteelP - Longitudinal Seam Welded PipeAp - ShipCd - Preferential Dissolution
Cm - Nital Etched Micrography by OMDf - Localized Corrosion
Micrographic detail of the autogenous seam weld. The localized dissolution occurrs exactly at the weld metal that presents a bainitic structure of average hardness about 230HV, compared to the heat affected zone presenting average of 202 HV and the base metal presenting average of 180HV.
57
VIEW
ML00140 / May.2019
Preferential Corrosion of Pipe Seam Weld
M - Low Carbon SteelP - Longitudinal Seam Welded PipeAp - ShipCd - Preferential Dissolution
Cm - Nital Etched Micrography by OMDf - Localized Corrosion
Micrographic detail presenting the slighltly decarburized ferritic structure, with inclusions, in the center of the weld, surrounded by a bainitic structure and the preferential corrosion in the weld.
51
VIEW
ML00140 / May.2019
Preferential Corrosion of Pipe Seam Weld
M - Low Carbon SteelP - Longitudinal Seam Welded PipeAp - ShipCd - Preferential Dissolution
Cm - Nital Etched Micrography by OMDf - Localized Corrosion

+5 more from this case →

ML00112 — 1" XXS Pipe Not Qualified For Low TempM - Low Carbon SteelP - Seamless PipeAp - RefineryCd - Not according to spec
Micrography of a transverse section of the pipe, close to the external surface (OD). The pipe presented a predominatly ferritic structure.
43
VIEW
ML00112 / Dec.2017
1" XXS Pipe Not Qualified For Low Temp
M - Low Carbon SteelP - Seamless PipeAp - RefineryCd - Not according to spec
Cm - Nital Etched Micrography by OMDf - Close to the External Surface
Micrography of a transverse section of the pipe, close to the external surface (OD). The pipe presented a 0.2 mm decarburized layer, fully ferritic.
35
VIEW
ML00112 / Dec.2017
1" XXS Pipe Not Qualified For Low Temp
M - Low Carbon SteelP - Seamless PipeAp - RefineryCd - Not according to spec
Cm - Nital Etched Micrography by OMDf - Close to the External Surface
Micrography of a transverse section of the pipe, close to the external surface (OD). The pipe presented a predominatly ferritic structure.
31
VIEW
ML00112 / Dec.2017
1" XXS Pipe Not Qualified For Low Temp
M - Low Carbon SteelP - Seamless PipeAp - RefineryCd - Not according to spec
Cm - Nital Etched Micrography by OMDf - Predominantly Ferritic
Micrography of a transverse section of the pipe, close to the internal surface (ID). The pipe presented a predominatly ferritic structure.
29
VIEW
ML00112 / Dec.2017
1" XXS Pipe Not Qualified For Low Temp
M - Low Carbon SteelP - Seamless PipeAp - RefineryCd - Not according to spec
Cm - Nital Etched Micrography by OMDf - Close to the Internal Surface
Micrography of a transverse section of the pipe, close to the internal surface (ID). The pipe presented a predominatly ferritic structure.
22
VIEW
ML00112 / Dec.2017
1" XXS Pipe Not Qualified For Low Temp
M - Low Carbon SteelP - Seamless PipeAp - RefineryCd - Not according to spec
Cm - Nital Etched Micrography by OMDf - Close to the Internal Surface

+2 more from this case →

ML00111 — 3/4" XXS Pipe Not Qualified for Low TempM - Low Carbon SteelP - Seamless PipeAp - RefineryCd - Not according to spec
Micrography of a transverse section of the pipe, close to the internal surface (ID). Refined structure. Ferrite and pearlite.
64
VIEW
ML00111 / Dec.2017
3/4" XXS Pipe Not Qualified for Low Temp
M - Low Carbon SteelP - Seamless PipeAp - RefineryCd - Not according to spec
Cm - Nital Etched Micrography by OMDf - Close to the Internal Surface
Micrography of a transverse section of the pipe, close to the internal surface (ID). Refined structure, but not uniform. Ferrite and pearlite. The pearlite colonies appear in a network.
45
VIEW
ML00111 / Dec.2017
3/4" XXS Pipe Not Qualified for Low Temp
M - Low Carbon SteelP - Seamless PipeAp - RefineryCd - Not according to spec
Cm - Nital Etched Micrography by OMDf - Close to the Internal Surface
Micrography of a transverse section of the pipe, close to the internal surface (ID). Refined structure. Ferrite and pearlite. The structure is not uniform. There is a large variation in the ferritic grain size and the pearlite colonies appear forming a network.
39
VIEW
ML00111 / Dec.2017
3/4" XXS Pipe Not Qualified for Low Temp
M - Low Carbon SteelP - Seamless PipeAp - RefineryCd - Not according to spec
Cm - Nital Etched Micrography by OMDf - Ferrite and Pearlite
Micrography of a transverse section of the pipe, close to the external surface (OD). Refined structure. Ferrite and pearlite.
33
VIEW
ML00111 / Dec.2017
3/4" XXS Pipe Not Qualified for Low Temp
M - Low Carbon SteelP - Seamless PipeAp - RefineryCd - Not according to spec
Cm - Nital Etched Micrography by OMDf - Close to the External Surface
Micrography of a transverse section of the pipe, close to the external surface (OD). Refined structure. Ferrite and pearlite.
35
VIEW
ML00111 / Dec.2017
3/4" XXS Pipe Not Qualified for Low Temp
M - Low Carbon SteelP - Seamless PipeAp - RefineryCd - Not according to spec
Cm - Nital Etched Micrography by OMDf - Close to the External Surface

+2 more from this case →

ML00072 — Liquation Cracks in a High Strength JointM - Low Alloy Medium Carbon QTP - Longitudinal Seam Welded PipeAp - O&G Well DrillingCd - Welding Defect
The liquation crack is a hot crack in the base metal (at the HAZ) that induces a solidification crack in the weld metal.
66
VIEW
ML00072 / Jan.2018
Liquation Cracks in a High Strength Joint
M - Low Alloy Medium Carbon QTP - Longitudinal Seam Welded PipeAp - O&G Well DrillingCd - Welding Defect
Cm - Nital Etched Micrography by OMDf - Weld Metal
Micrographic detail of the cracks at the fusion line of the welded joint, at the connector side. The cracking presents morphology of melting regions of impurities at grain boundaries of the large grains of the heat affected zone (HAZ).
57
VIEW
ML00072 / Jan.2018
Liquation Cracks in a High Strength Joint
M - Low Alloy Medium Carbon QTP - Longitudinal Seam Welded PipeAp - O&G Well DrillingCd - Welding Defect
Cm - Nital Etched Micrography by OMDf - Fusion Line
The HAZ presents microcracks at previous austenite grain boundaries. These regions melted during welding and generated cracks associated to low melting temperature phases.
48
VIEW
ML00072 / Jan.2018
Liquation Cracks in a High Strength Joint
M - Low Alloy Medium Carbon QTP - Longitudinal Seam Welded PipeAp - O&G Well DrillingCd - Welding Defect
Cm - Nital Etched Micrography by OMDf - Microcracks
The HAZ presents microcracks at previous austenite grain boundaries. These regions melted during welding and generated cracks associated to low melting temperature phases.
43
VIEW
ML00072 / Jan.2018
Liquation Cracks in a High Strength Joint
M - Low Alloy Medium Carbon QTP - Longitudinal Seam Welded PipeAp - O&G Well DrillingCd - Welding Defect
Cm - Nital Etched Micrography by OMDf - Microcracks
Micrography of the AISI 4130 forging, 5/8" thickness, close to the welded region, in the longitudinal section.
42
VIEW
ML00072 / Jan.2018
Liquation Cracks in a High Strength Joint
M - Low Alloy Medium Carbon QTP - Longitudinal Seam Welded PipeAp - O&G Well DrillingCd - Welding Defect
Cm - Nital Etched Micrography by OMDf - Base Metal Left Side

+7 more from this case →

ML00068 — Corrosion Fatigue of a 5" Drill PipeM - Low Alloy Medium Carbon QTP - Seamless PipeAp - O&G Well DrillingCd - Corrosion Fatigue
The micrography of one of the (multiple) cracks shows the slightly irregular morphology of the cracking, typical of a corrosion-fatigue mechanism.
281
VIEW
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 Micrography by OMDf - Corrosion Cracking
Micrographic detail of the slightly irregular crack propagation, typical of a corrosion-fatigue mechanism.
76
VIEW
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 Micrography by OMDf - Corrosion Cracking
ML00034 — 45 Years Old Acquaduct Grey Cast IronM - Gray Cast ironP - Centrifugally Cast PipeAp - AcquaductCd - General Corrosion
Micrographic detail of the graphite/matrix interface corrosion, leading to a general corrosion loss.
189
VIEW
ML00034 / Apr.2017
45 Years Old Acquaduct Grey Cast Iron
M - Gray Cast ironP - Centrifugally Cast PipeAp - AcquaductCd - General Corrosion
Cm - Nital Etched Micrography by OMDf - Graphite in Flakes
Micrography of the longitudinal section of the pipe, close to the internal surface, showing graphite in flakes and ferritic matrix with small regions of perlite.
231
VIEW
ML00034 / Apr.2017
45 Years Old Acquaduct Grey Cast Iron
M - Gray Cast ironP - Centrifugally Cast PipeAp - AcquaductCd - General Corrosion
Cm - Nital Etched Micrography by OMDf - Predominantly Ferritic Matrix
Micrography of the longitudinal section of the pipe, close to the internal surface, showing graphite in flakes and ferritic matrix with small regions of perlite and eutetic in the middle of the perlite colonies.
192
VIEW
ML00034 / Apr.2017
45 Years Old Acquaduct Grey Cast Iron
M - Gray Cast ironP - Centrifugally Cast PipeAp - AcquaductCd - General Corrosion
Cm - Nital Etched Micrography by OMDf - Predominantly Ferritic Matrix
Micrography of the longitudinal section of the pipe, in the center of the thickness. Graphite in flakes and ferritic matrix with small regions of perlite.
179
VIEW
ML00034 / Apr.2017
45 Years Old Acquaduct Grey Cast Iron
M - Gray Cast ironP - Centrifugally Cast PipeAp - AcquaductCd - General Corrosion
Cm - Nital Etched Micrography by OMDf - Predominantly Ferritic Matrix
Micrography of the longitudinal section of the pipe, in the center of the thickness. Graphite in flakes and ferritic matrix with small regions of perlite.
162
VIEW
ML00034 / Apr.2017
45 Years Old Acquaduct Grey Cast Iron
M - Gray Cast ironP - Centrifugally Cast PipeAp - AcquaductCd - General Corrosion
Cm - Nital Etched Micrography by OMDf - Ferrite and Pearlite

+4 more from this case →