A

4 cases · 56 images

Crevice Corrosion in a Subsea System — Aspect Before Analysis

A — sub-branches

Micrographic detail of the longitudinal section of the tube, close to the external surface. 
The carburizing layer consists of a bainitic structure, with intergranular and intragranular carbide precipitation.
1185
ML00107 / Dec.2017
Carburized 9Cr1MoV Superheater Tube
M - Heat Resistant SteelP - Seamless tubeAp - BoilerCd - Carburization
Cm - Nital Etched Micrography by OMDf - Carburized Layer
The scanning electron microscopy image of the internal surface of the tube in position 2 shows a localized  corrosion region with intergranular morphology, as well a crack from the corroded region.
1237
ML00086 / Nov.2017
Intergranular Corrosion of Sensitized 304SS
M - Austenitic Stainless SteelP - Seamless tubeAp - Heat ExchangerCd - Intergranular Corrosion
Cm - Surface Aspect by SEMDf - Intergranular Corrosion
Macrography showing the different regions of a pipe-to-plate fillet weld. See the schematic drawing in the next image
954
ML00052 / Apr.2017
Cold Cracks in API 5CT L80 Tube Welded to a Structural Part
M - Low Alloy SteelP - Seamless tubeAp - OffshoreCd - Welding Defect
Cm - NItal Etched MacroDf - Fracture
Image by scanning electron microscopy of the metallurgically bonded interface of the composite seamless tube (carbon steel externally claded with stainless steel), in the side of the stainless steel where a strain hardening effect plus a carbide precipitation in twins is shown.  The hardness of this region (279 HV0.3) is a lot higher than the value obtained out of this region (167 HV0.3) for the same stainless steel.
814
ML00056 / May.2018
Seamless Tube Externally Cladded with SS
M - Carbon Steel / Stainless SteelP - CladdingAp - Pulp and PaperCd - Removed From Service
Cm - Electrolytic Etch Micrography by SEMDf - Clad Interface

More from these cases

ML00107 — Carburized 9Cr1MoV Superheater TubeM - Heat Resistant SteelP - Seamless tubeAp - BoilerCd - Carburization
Micrography of the longitudinal section of the tube, close to the internal surface. 
A thick scale is evident, but no microstructural changes compared to the center of the tube.
183
ML00107 / Dec.2017
Carburized 9Cr1MoV Superheater Tube
M - Heat Resistant SteelP - Seamless tubeAp - BoilerCd - Carburization
Cm - Nital Etched Micrography by OMDf - Bainite
Aspect of the superheater ND 1" tube that was in operation for about 35,000 hours and presented a thick deposit at the external surface.
211
ML00107 / Dec.2017
Carburized 9Cr1MoV Superheater Tube
M - Heat Resistant SteelP - Seamless tubeAp - BoilerCd - Carburization
Cm - Aspect Before AnalysisDf - General View
Micrography of a longitudinal section of the tube in the center of the thickness, showing a ferritic-bainitic structure of this CrMoV steel.
156
ML00107 / Dec.2017
Carburized 9Cr1MoV Superheater Tube
M - Heat Resistant SteelP - Seamless tubeAp - BoilerCd - Carburization
Cm - Nital Etched Micrography by OMDf - Bainite
Micrography of a longitudinal section of the tube in the center of the thickness, showing a ferritic-bainitic structure of this CrMoV steel.
137
ML00107 / Dec.2017
Carburized 9Cr1MoV Superheater Tube
M - Heat Resistant SteelP - Seamless tubeAp - BoilerCd - Carburization
Cm - Nital Etched Micrography by OMDf - Bainite
Micrography of a longitudinal section of the tube in the center of the thickness, showing a ferritic-bainitic structure of this CrMoV steel.
142
ML00107 / Dec.2017
Carburized 9Cr1MoV Superheater Tube
M - Heat Resistant SteelP - Seamless tubeAp - BoilerCd - Carburization
Cm - Nital Etched Micrography by OMDf - Bainite

+9 more from this case →

ML00086 — Intergranular Corrosion of Sensitized 304SSM - Austenitic Stainless SteelP - Seamless tubeAp - Heat ExchangerCd - Intergranular Corrosion
Micrography of the 1.65 mm thickness tube, in the middle of the thickness of the longitudinal section.  This part of the tube is located in the colder part of the equipment, position 1.  The material presented carbide precipitation at grain boundaries (not yet fully surrounding the grains) and at this point the tube presented no internal corrosion.
338
ML00086 / Nov.2017
Intergranular Corrosion of Sensitized 304SS
M - Austenitic Stainless SteelP - Seamless tubeAp - Heat ExchangerCd - Intergranular Corrosion
Cm - Micrography by OM using A262 Method ADf - Austenite
Micrography of the 1.65 mm thickness tube, in the middle of the thickness of the longitudinal section.  This part of the tube is located in position 2, where the temperature was higher and the carbide precipitation increased during service.
272
ML00086 / Nov.2017
Intergranular Corrosion of Sensitized 304SS
M - Austenitic Stainless SteelP - Seamless tubeAp - Heat ExchangerCd - Intergranular Corrosion
Cm - Micrography by OM using A262 Method ADf - Intergranular Precipitation
Micrography of the 1.65 mm thickness tube, in the middle of the thickness of the longitudinal section.  This part of the tube is located in position 3, where intergranular and transgranular carbide precipitation occurred during service.
234
ML00086 / Nov.2017
Intergranular Corrosion of Sensitized 304SS
M - Austenitic Stainless SteelP - Seamless tubeAp - Heat ExchangerCd - Intergranular Corrosion
Cm - Micrography by OM using A262 Method ADf - Intragranular Secondary Precipitation
The low magnification image of the internal surface of the tube, in position 2, shows several points of localized corrosion, with intergranular morphology.
193
ML00086 / Nov.2017
Intergranular Corrosion of Sensitized 304SS
M - Austenitic Stainless SteelP - Seamless tubeAp - Heat ExchangerCd - Intergranular Corrosion
Cm - Surface Aspect by SEMDf - Intergranular Corrosion
Micrography of a longitudinal section of the tube in position 2, presenting thinning by intergranular corrosion at the internal surface.
193
ML00086 / Nov.2017
Intergranular Corrosion of Sensitized 304SS
M - Austenitic Stainless SteelP - Seamless tubeAp - Heat ExchangerCd - Intergranular Corrosion
Cm - Micrography by OM using A262 Method ADf - Intergranular Corrosion

+3 more from this case →

ML00052 — Cold Cracks in API 5CT L80 Tube Welded to a Structural PartM - Low Alloy SteelP - Seamless tubeAp - OffshoreCd - Welding Defect
ML00052 / Apr.2017
Cold Cracks in API 5CT L80 Tube Welded to a Structural Part
M - Low Alloy SteelP - Seamless tubeAp - OffshoreCd - Welding Defect
Cm - Identification drawingDf - Fracture
ML00052 / Apr.2017
Cold Cracks in API 5CT L80 Tube Welded to a Structural Part
M - Low Alloy SteelP - Seamless tubeAp - OffshoreCd - Welding Defect
Cm - NItal Etched MacroDf - Welded Joint
ML00052 / Apr.2017
Cold Cracks in API 5CT L80 Tube Welded to a Structural Part
M - Low Alloy SteelP - Seamless tubeAp - OffshoreCd - Welding Defect
Cm - Identification drawingDf - Welded Joint
ML00052 / Apr.2017
Cold Cracks in API 5CT L80 Tube Welded to a Structural Part
M - Low Alloy SteelP - Seamless tubeAp - OffshoreCd - Welding Defect
Cm - Nital Etched Micrography by OMDf - Cracking
ML00052 / Apr.2017
Cold Cracks in API 5CT L80 Tube Welded to a Structural Part
M - Low Alloy SteelP - Seamless tubeAp - OffshoreCd - Welding Defect
Cm - Nital Etched Micrography by OMDf - Base Metal

+13 more from this case →

ML00056 — Seamless Tube Externally Cladded with SSM - Carbon Steel / Stainless SteelP - CladdingAp - Pulp and PaperCd - Removed From Service
The 2 1/2" nominal diameter seamless tube is externally cladded with stainless steel.
196
ML00056 / May.2018
Seamless Tube Externally Cladded with SS
M - Carbon Steel / Stainless SteelP - CladdingAp - Pulp and PaperCd - Removed From Service
Cm - Aspect Before AnalysisDf - Welded Joint
The macrography of a transverse section shows the carbon steel tube, externally cladded with stainless steel.  The tube was removed from service where it was welded to other tubes to form a wall.
156
ML00056 / May.2018
Seamless Tube Externally Cladded with SS
M - Carbon Steel / Stainless SteelP - CladdingAp - Pulp and PaperCd - Removed From Service
Cm - Kalling Etched MacroDf - Transverse Section
Macrography of the tube transversal section presenting the studied assembly.
138
ML00056 / May.2018
Seamless Tube Externally Cladded with SS
M - Carbon Steel / Stainless SteelP - CladdingAp - Pulp and PaperCd - Removed From Service
Cm - Macro Oxalic Acid Electrolytic EtchedDf - Transverse Section
Micrography of a longitudinal section of the pipe showing that the carbon steel pipe is slightly banded and there is a decarburized layer at the solid solution welded interface. The stainless steel structure (in the right side of the figure) is not revealed using the Nital etch.
126
ML00056 / May.2018
Seamless Tube Externally Cladded with SS
M - Carbon Steel / Stainless SteelP - CladdingAp - Pulp and PaperCd - Removed From Service
Cm - Nital Etched Micrography by OMDf - Longitudinal Section
Micrography of a longitudinal section of the pipe showing the carbon steel pipe , internal.
123
ML00056 / May.2018
Seamless Tube Externally Cladded with SS
M - Carbon Steel / Stainless SteelP - CladdingAp - Pulp and PaperCd - Removed From Service
Cm - Nital Etched Micrography by OMDf - Ferrite and Pearlite

+7 more from this case →