182

6 cases · 35 images

Crevice Corrosion in a Subsea System — Aspect Before Analysis

Capture method: Scanning Electron Microscope clear all

182 — sub-branches

grade F22 1grade F51 1grade F53 1grade F55 2grade F6NM 1

Results

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Fusion line at the forging side. The weld metal to the top and the heat affected zone to the bottom.
84
VIEW
ML00178 / Jan.2022
Cold cracks in Cr-Mo Welded Forging
M - CrMo SteelP - ForgingAp - O&G Well DrillingCd - Welding Defect
Cm - Nital Etched Micrography by SEMDf - Fusion Line
The same fracture appearance of the previous figure, looking at a higher magnification by scanning electron microscopy. The fracture is clean, flat, starting in the right side of the figure, at the margem of the weld and propagating into the pipe thickness. The external side of the pipe is to the right side of the figure and the internal side of the pipe is to the left side of the figure.
154
VIEW
ML00150 / Dec.2018
Vibration Induced Fatigue in a SS Oil Piping
M - Duplex Stainless SteelP - PipingAp - FPSOCd - Vibration Induced Fatigue
Cm - Fractography by SEMDf - Fracture
Microstructural analysis of the valve body structure, close to the position where the cracking has occurred. The structure is ferritic austenitic, with a large amount of detrimental phases associated to the ferritic structure, probably sigma phase.
92
VIEW
ML00134 / Aug.2020
Brittle Fracture of a Superduplex Valve Body
M - Super Duplex Stainless SteelP - Fabrication WeldAp - SubseaCd - Brittle Fracture
Cm - Micrography by SEMDf - Sigma
Fractographic detail of the longitudinal Charpy V testpiece, broken at -46°C and presenting energy of 64J (the average energy of three tespieces was 70J). The Charpy V testpiece was removed from the center of the bar. The micromechanism is quasicleavage and the test in this direction presented energy values superior than the minimum requirement of 45J.
944
VIEW
ML00123 / Feb.2018
Non Qualified Superduplex for Subsea
M - Super Duplex Stainless SteelP - BarAp - Oil and GasCd - Not according to spec
Cm - Fractography by SEMDf - Broken Testpiece
Fusion line micrographic detail. The weld metal is in the right and HAZ in the left.
27
VIEW
ML00045 / Aug.2017
Subsea Tubular F6NM Martensitic SS
M - Martensitic Stainless SteelP - Fabrication WeldAp - OffshoreCd - Welding
Cm - Kalling Etched Micrography by SEMDf - Fusion Line
External surface aspect of the flange showing preferential dissolution, responsible for nucleation of the through wall cracking.
245
VIEW
ML00002 / Jan.2018
Preferential Dissolution and Cracks in SDSS
M - Super Duplex Stainless SteelP - Fabrication WeldAp - PipingCd - Preferential Dissolution
Cm - Surface Aspect by SEMDf - Preferential Dissolution

More from these cases

ML00178 — Cold cracks in Cr-Mo Welded ForgingM - CrMo SteelP - ForgingAp - O&G Well DrillingCd - Welding Defect
Quenched and tempered heat affected zone of the forging.
75
VIEW
ML00178 / Jan.2022
Cold cracks in Cr-Mo Welded Forging
M - CrMo SteelP - ForgingAp - O&G Well DrillingCd - Welding Defect
Cm - Nital Etched Micrography by SEMDf - Heat Affected Zone
The cracking is located at the margin of the weld in the forging side. It is 1.2 mm deep.
66
VIEW
ML00178 / Jan.2022
Cold cracks in Cr-Mo Welded Forging
M - CrMo SteelP - ForgingAp - O&G Well DrillingCd - Welding Defect
Cm - Nital Etched Micrography by SEMDf - Cracking
The intergranular morphology of the cracks, at the heat affected zone of the forging, indicates it is a cold cracking probably formed when the welded joint was not yet post welding heat treated. The actual hardness values at the HAZ is 270HV10, and when it was cracked it was probably a lot higher.
71
VIEW
ML00178 / Jan.2022
Cold cracks in Cr-Mo Welded Forging
M - CrMo SteelP - ForgingAp - O&G Well DrillingCd - Welding Defect
Cm - Nital Etched Micrography by SEMDf - Intergranular Cracking
Detail of the cold cracking at the previous austenite grain boundary of the martensitic structure.
62
VIEW
ML00178 / Jan.2022
Cold cracks in Cr-Mo Welded Forging
M - CrMo SteelP - ForgingAp - O&G Well DrillingCd - Welding Defect
Cm - Nital Etched Micrography by SEMDf - Cold cracking
Detail of the cold cracking at the previous austenite grain boundary of the martensitic structure.
55
VIEW
ML00178 / Jan.2022
Cold cracks in Cr-Mo Welded Forging
M - CrMo SteelP - ForgingAp - O&G Well DrillingCd - Welding Defect
Cm - Nital Etched Micrography by SEMDf - Intergranular Cracking

+3 more from this case →

ML00150 — Vibration Induced Fatigue in a SS Oil PipingM - Duplex Stainless SteelP - PipingAp - FPSOCd - Vibration Induced Fatigue
Fracture apperance by scanning electron microscopy of the region where the fatigue crack started, from the piping outside . The fracture is flat, presents some smashed regions close to the surface (to the right side) and there are some thin secondary cracks.
140
VIEW
ML00150 / Dec.2018
Vibration Induced Fatigue in a SS Oil Piping
M - Duplex Stainless SteelP - PipingAp - FPSOCd - Vibration Induced Fatigue
Cm - Fractography by SEMDf - Fatigue Fracture
Fracture detail by scanning electron microscopy of the region where the cracking started, from the piping outside . The fracture is flat and shows fatigue striation.
138
VIEW
ML00150 / Dec.2018
Vibration Induced Fatigue in a SS Oil Piping
M - Duplex Stainless SteelP - PipingAp - FPSOCd - Vibration Induced Fatigue
Cm - Fractography by SEMDf - Fatigue Striation
Fracture apperance by scanning electron microscopy in the center of the thickness where the crack propagated through wall. The fracture is flat and the striation is not so clear at this magnification.
133
VIEW
ML00150 / Dec.2018
Vibration Induced Fatigue in a SS Oil Piping
M - Duplex Stainless SteelP - PipingAp - FPSOCd - Vibration Induced Fatigue
Cm - Fractography by SEMDf - Fatigue Fracture
Fracture detail by scanning electron microscopy of the region cloin the center of the thockness. The fracture is flat and shows fatigue striation.
118
VIEW
ML00150 / Dec.2018
Vibration Induced Fatigue in a SS Oil Piping
M - Duplex Stainless SteelP - PipingAp - FPSOCd - Vibration Induced Fatigue
Cm - Fractography by SEMDf - Fatigue Striation
ML00134 — Brittle Fracture of a Superduplex Valve BodyM - Super Duplex Stainless SteelP - Fabrication WeldAp - SubseaCd - Brittle Fracture
Micrographic details by scaning electron microscopy. The structure is ferritic austenitic, with a large amount of detrimental phases associated to the ferritic structure, probably sigma phase.
85
VIEW
ML00134 / Aug.2020
Brittle Fracture of a Superduplex Valve Body
M - Super Duplex Stainless SteelP - Fabrication WeldAp - SubseaCd - Brittle Fracture
Cm - Micrography by SEMDf - Sigma
High magnification details by scaning electron microscopy. The structure is ferritic austenitic, with a large amount of detrimental phases associated to the ferritic structure, probably sigma phase.
81
VIEW
ML00134 / Aug.2020
Brittle Fracture of a Superduplex Valve Body
M - Super Duplex Stainless SteelP - Fabrication WeldAp - SubseaCd - Brittle Fracture
Cm - Micrography by SEMDf - Sigma
Higher magnification detail of the sigma phase by scaning electron microscopy.
76
VIEW
ML00134 / Aug.2020
Brittle Fracture of a Superduplex Valve Body
M - Super Duplex Stainless SteelP - Fabrication WeldAp - SubseaCd - Brittle Fracture
Cm - Micrography by SEMDf - Sigma
Fractographic aspect of the valve body fracture surface after opening the crack. The fracture micromechanism is brittle, by cleavage, with several secondary microcracks associated to the sigma phase.
54
VIEW
ML00134 / Aug.2020
Brittle Fracture of a Superduplex Valve Body
M - Super Duplex Stainless SteelP - Fabrication WeldAp - SubseaCd - Brittle Fracture
Cm - Fractography by SEMDf - Cleavage Facets
Fractographic detail of the valve body fracture surface after opening the crack. The fracture micromechanism is brittle, by cleavage, with several secondary microcracks associated to the sigma phase.
52
VIEW
ML00134 / Aug.2020
Brittle Fracture of a Superduplex Valve Body
M - Super Duplex Stainless SteelP - Fabrication WeldAp - SubseaCd - Brittle Fracture
Cm - Fractography by SEMDf - Cleavage Facets

+1 more from this case →

ML00123 — Non Qualified Superduplex for SubseaM - Super Duplex Stainless SteelP - BarAp - Oil and GasCd - Not according to spec
Fractography of the broken Charpy V testpiece, longitudinal, broken at -46°C and presenting energy of 64J (the average of three values was 70J). In this direction the material presented an energy value higher than the minimum requirement of 45J.
109
VIEW
ML00123 / Feb.2018
Non Qualified Superduplex for Subsea
M - Super Duplex Stainless SteelP - BarAp - Oil and GasCd - Not according to spec
Cm - Fractography by SEMDf - Broken Testpiece
Fractography of the Charpy V testpiece, transverse section, broken at -46°C and presenting energy of 20J (the average of three results was 33J). The coarse structure and the alignement created a condition for low energy results in this specific direction, and the material did not present the minimum requirement of 45J.
103
VIEW
ML00123 / Feb.2018
Non Qualified Superduplex for Subsea
M - Super Duplex Stainless SteelP - BarAp - Oil and GasCd - Not according to spec
Cm - Fractography by SEMDf - Broken Testpiece
ML00045 — Subsea Tubular F6NM Martensitic SSM - Martensitic Stainless SteelP - Fabrication WeldAp - OffshoreCd - Welding
Micrographic detail of the base metal tempered martensite.
24
VIEW
ML00045 / Aug.2017
Subsea Tubular F6NM Martensitic SS
M - Martensitic Stainless SteelP - Fabrication WeldAp - OffshoreCd - Welding
Cm - Kalling Etched Micrography by SEMDf - Base Metal
Micrographic detail of the weld metal tempered martensitic microstructure.
25
VIEW
ML00045 / Aug.2017
Subsea Tubular F6NM Martensitic SS
M - Martensitic Stainless SteelP - Fabrication WeldAp - OffshoreCd - Welding
Cm - Kalling Etched Micrography by SEMDf - Weld Metal
ML00002 — Preferential Dissolution and Cracks in SDSSM - Super Duplex Stainless SteelP - Fabrication WeldAp - PipingCd - Preferential Dissolution
Detail of the region at the flange external surface where the material is suffering the preferential corrosion.
177
VIEW
ML00002 / Jan.2018
Preferential Dissolution and Cracks in SDSS
M - Super Duplex Stainless SteelP - Fabrication WeldAp - PipingCd - Preferential Dissolution
Cm - Surface Aspect by SEMDf - Preferential Dissolution
Micrographic detail of the through wall cracking in the middle of the thickness, showing that the cracking is associated to ferrite network in the (super)duplex microstructure.
128
VIEW
ML00002 / Jan.2018
Preferential Dissolution and Cracks in SDSS
M - Super Duplex Stainless SteelP - Fabrication WeldAp - PipingCd - Preferential Dissolution
Cm - Micrography by SEMDf - Crack
Micrographic detail of the cracking, associated to the ferrite network, that presents both corrosion (preferential dissolution) and fracture (clevage) aspects.
128
VIEW
ML00002 / Jan.2018
Preferential Dissolution and Cracks in SDSS
M - Super Duplex Stainless SteelP - Fabrication WeldAp - PipingCd - Preferential Dissolution
Cm - Electrolytic Etch Micrography by SEMDf - Crack
The fracture surface, although presenting a large amount of corrosion products, shows also evidences of a brittle behavior with regions of cleavage micromechanism.
116
VIEW
ML00002 / Jan.2018
Preferential Dissolution and Cracks in SDSS
M - Super Duplex Stainless SteelP - Fabrication WeldAp - PipingCd - Preferential Dissolution
Cm - Fractography by SEMDf - Cleavage Facets
Micrographic detail of the ferrite network with evidences of precipitation/formation of detrimental phases. NaOH solution was adopted for the electrolytic etching.
86
VIEW
ML00002 / Jan.2018
Preferential Dissolution and Cracks in SDSS
M - Super Duplex Stainless SteelP - Fabrication WeldAp - PipingCd - Preferential Dissolution
Cm - Electrolytic Etch Micrography by SEMDf - Delta ferrite

+2 more from this case →