A

10 cases · 115 images

Crevice Corrosion in a Subsea System — Aspect Before Analysis

Optical micrography of a longitudinal section of the fractured bolt, at the thread.  The material is austenitic, free from carbides, and the threads were almost removed by the stress corrosion cracks.
756
ML00157 / Feb.2020
Bolts Under Chloride SCC Conditions
M - Austenitic Stainless SteelP - BoltAp - Oil and GasCd - Stress Corrosion
Cm - Oxalic Acid Electrolytic EtchDf - Stress Corrosion Cracks
Nitronic 60 cylinder. Scanning electron microscopy image of a corroded region at the external surface of the cylinder, that is austenitic.  The image shows the localized corroded regions in form of pits.
1228
ML00121 / Feb.2018
Pitting Corrosion in a Subsea System
M - Austenitic / MartensiticP - Rod & CylinderAp - SubseaCd - Pitting Corrosion
Cm - Surface Aspect by SEMDf - Localized Corrosion
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
Micrography of the new tube close to a region of a casting defect (shrinkage), presenting only austenitic structure with a network of primary precipitates.
351
ML00097 / Nov.2017
Cast SS Tube Removed From High Temperature Service
M - Heat Resistant SteelP - Centrifugally Cast PipeAp - SiderurgyCd - High Temperature
Cm - Glyceregia Etched Micrography by OMDf - Austenitic with Primary Carbides
Micrographic detail of the fatigue cracking at the margin of the flange to shell fillet weld.
484
ML00050 / Nov.2017
Fatigue Failure of a 316SS Pressure Stabilizer
M - Austenitic Stainless SteelP - Fabrication WeldAp - Chemical IndustryCd - Mechanical Fatigue
Cm - Micrography by OM using A262 Method ADf - Fatigue Crack
Aspect of the cracking after Dye Check Test (Liquid Penetrant) in the external side of the line that operates at 800°C, insulated, and presented the leakage associated to the longitudinal seam weld of the fitting. The circumferential butt weld of the fitting to a pipe did not fail. See the schematic drawing in the next figure
371
ML00061 / Apr.2017
Creep in a Seam Weld of a 304H SS Fitting
M - Austenitic Stainless SteelP - Fabrication WeldAp - Chemical IndustryCd - Creep
Cm - Aspect by NDTDf - Through Wall Cracking
The micrography of the transverse section of the plate, as polished, close to the surface.  The material presents intergranular corrosion and some grains were lost.
1184
ML00015 / Oct.2017
Intergranular Corrosion of 304SS Plate
M - Austenitic Stainless SteelP - Rolled PlateAp - RefineryCd - Intergranular Corrosion
Cm - Micrography by OMDf - Intergranular Corrosion
Micrography of the transverse section of the NEW TUBE, in the center of the thickness, showing the austenitic structure with primary carbides network.
410
ML00038 / Apr.2017
Cast SS Tube for High Temperature Service
M - Heat Resistant SteelP - Centrifugally Cast PipeAp - SiderurgyCd - Creep
Cm - Glyceregia Etched Micrography by OMDf - Austenitic with Primary Carbides

More from these cases

ML00157 — Bolts Under Chloride SCC ConditionsM - Austenitic Stainless SteelP - BoltAp - Oil and GasCd - Stress Corrosion
Aspect of a 5/16" bolt manufactured in an AISI 316 austenitic stainless steel, that was also operating inside the pressure vessel, but was not yet damaged.  It is a hexagonal head bolt, 1 1/2" long, fastened with a hexagonal nut and a lock washer.
118
ML00157 / Feb.2020
Bolts Under Chloride SCC Conditions
M - Austenitic Stainless SteelP - BoltAp - Oil and GasCd - Stress Corrosion
Cm - Aspect Before AnalysisDf - General View
Low magnification micrography, by optical microscope, of the longitudinal section of a damaged bolt, in the center of the thickness. The microstructure is austenitic, free from carbides.
100
ML00157 / Feb.2020
Bolts Under Chloride SCC Conditions
M - Austenitic Stainless SteelP - BoltAp - Oil and GasCd - Stress Corrosion
Cm - Oxalic Acid Electrolytic EtchDf - Austenite
ML00157 / Feb.2020
Bolts Under Chloride SCC Conditions
M - Austenitic Stainless SteelP - BoltAp - Oil and GasCd - Stress Corrosion
Cm - Nital Etched Micrography by OMDf - Strain Hardened
ML00157 / Feb.2020
Bolts Under Chloride SCC Conditions
M - Austenitic Stainless SteelP - BoltAp - Oil and GasCd - Stress Corrosion
Cm - Oxalic Acid Electrolytic EtchDf - Strain Hardened
ML00157 / Feb.2020
Bolts Under Chloride SCC Conditions
M - Austenitic Stainless SteelP - BoltAp - Oil and GasCd - Stress Corrosion
Cm - Aspect Before AnalysisDf - Fracture

+8 more from this case →

ML00121 — Pitting Corrosion in a Subsea SystemM - Austenitic / MartensiticP - Rod & CylinderAp - SubseaCd - Pitting Corrosion
Aspect of the Nitronic 60 cylinder, OD 36.4mm, presenting pits at the external surface.
219
ML00121 / Feb.2018
Pitting Corrosion in a Subsea System
M - Austenitic / MartensiticP - Rod & CylinderAp - SubseaCd - Pitting Corrosion
Cm - Aspect Before AnalysisDf - External Surface
Nitronic 60 cylinder. Detailed aspect of the pitting in a low magnification microscope.
197
ML00121 / Feb.2018
Pitting Corrosion in a Subsea System
M - Austenitic / MartensiticP - Rod & CylinderAp - SubseaCd - Pitting Corrosion
Cm - Surface AspectDf - Pitting
Nitronic 60 cylinder. Micrography of the longitudinal section in the center of the thickness, presenting a fully austenitic microstructure, equiaxial grains, and evidences of the manufacturing process by hot forming.
179
ML00121 / Feb.2018
Pitting Corrosion in a Subsea System
M - Austenitic / MartensiticP - Rod & CylinderAp - SubseaCd - Pitting Corrosion
Cm - Micrography by OM using A262 Method ADf - Austenite
Nitronic 60 cylinder. Micrography of the longitudinal section in the center of the thickness, presenting a fully austenitic microstructure, with some aligned non metallic inclusions.
157
ML00121 / Feb.2018
Pitting Corrosion in a Subsea System
M - Austenitic / MartensiticP - Rod & CylinderAp - SubseaCd - Pitting Corrosion
Cm - Micrography by OM using A262 Method ADf - Austenite
Nitronic 60 cylinder. Micrographic detail of the longitudinal section in the center of the thickness, presenting a fully austenitic microstructure, equiaxial grains, typical of a solution annealed condition.
136
ML00121 / Feb.2018
Pitting Corrosion in a Subsea System
M - Austenitic / MartensiticP - Rod & CylinderAp - SubseaCd - Pitting Corrosion
Cm - Micrography by OM using A262 Method ADf - Austenite

+14 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 →

ML00097 — Cast SS Tube Removed From High Temperature ServiceM - Heat Resistant SteelP - Centrifugally Cast PipeAp - SiderurgyCd - High Temperature
ML00097 / Nov.2017
Cast SS Tube Removed From High Temperature Service
M - Heat Resistant SteelP - Centrifugally Cast PipeAp - SiderurgyCd - High Temperature
Cm - Transverse Section AspectDf - Casting Structure
ML00097 / Nov.2017
Cast SS Tube Removed From High Temperature Service
M - Heat Resistant SteelP - Centrifugally Cast PipeAp - SiderurgyCd - High Temperature
Cm - As polished micrographyDf - Close to the External Surface
ML00097 / Nov.2017
Cast SS Tube Removed From High Temperature Service
M - Heat Resistant SteelP - Centrifugally Cast PipeAp - SiderurgyCd - High Temperature
Cm - As polished micrographyDf - Close to the Internal Surface
ML00097 / Nov.2017
Cast SS Tube Removed From High Temperature Service
M - Heat Resistant SteelP - Centrifugally Cast PipeAp - SiderurgyCd - High Temperature
Cm - Glyceregia Etched Micrography by OMDf - Intragranular Secondary Precipitation
ML00097 / Nov.2017
Cast SS Tube Removed From High Temperature Service
M - Heat Resistant SteelP - Centrifugally Cast PipeAp - SiderurgyCd - High Temperature
Cm - Transverse Section AspectDf - Casting Structure

+2 more from this case →

ML00050 — Fatigue Failure of a 316SS Pressure StabilizerM - Austenitic Stainless SteelP - Fabrication WeldAp - Chemical IndustryCd - Mechanical Fatigue
Aspect of the equipment presenting a through wall cracking at the margin of the fillet weld.
142
ML00050 / Nov.2017
Fatigue Failure of a 316SS Pressure Stabilizer
M - Austenitic Stainless SteelP - Fabrication WeldAp - Chemical IndustryCd - Mechanical Fatigue
Cm - Aspect Before AnalysisDf - Cracking
Macrography of the welded joint between the flange and the shell, indicating the position where the cracking   was detected, at 90°.
116
ML00050 / Nov.2017
Fatigue Failure of a 316SS Pressure Stabilizer
M - Austenitic Stainless SteelP - Fabrication WeldAp - Chemical IndustryCd - Mechanical Fatigue
Cm - Macro Oxalic Acid Electrolytic EtchedDf - Welded Joint
The shell plate micrography showed an austenitic structure.
101
ML00050 / Nov.2017
Fatigue Failure of a 316SS Pressure Stabilizer
M - Austenitic Stainless SteelP - Fabrication WeldAp - Chemical IndustryCd - Mechanical Fatigue
Cm - Micrography by OM using A262 Method ADf - Austenite
ML00050 / Nov.2017
Fatigue Failure of a 316SS Pressure Stabilizer
M - Austenitic Stainless SteelP - Fabrication WeldAp - Chemical IndustryCd - Mechanical Fatigue
Cm - Transverse Section AspectDf - Cracking
Fracture surface after opening the shell cracking, presenting fatigue striation.  The fracture presents also foreign particles.
132
ML00050 / Nov.2017
Fatigue Failure of a 316SS Pressure Stabilizer
M - Austenitic Stainless SteelP - Fabrication WeldAp - Chemical IndustryCd - Mechanical Fatigue
Cm - Fractography by SEMDf - Fatigue Striation

+3 more from this case →

ML00061 — Creep in a Seam Weld of a 304H SS FittingM - Austenitic Stainless SteelP - Fabrication WeldAp - Chemical IndustryCd - Creep
ML00061 / Apr.2017
Creep in a Seam Weld of a 304H SS Fitting
M - Austenitic Stainless SteelP - Fabrication WeldAp - Chemical IndustryCd - Creep
Cm - Identification drawingDf - Through Wall Cracking
ML00061 / Apr.2017
Creep in a Seam Weld of a 304H SS Fitting
M - Austenitic Stainless SteelP - Fabrication WeldAp - Chemical IndustryCd - Creep
Cm - Macro Oxalic Acid Electrolytic EtchedDf - Transverse Section
Through wall cracking in the longitudinal seam weld of the fitting.  Several cracks, longitudinal to the weld, were created by the connection of voids in the weld metal, associated to a strong microstructural evolution.
191
ML00061 / Apr.2017
Creep in a Seam Weld of a 304H SS Fitting
M - Austenitic Stainless SteelP - Fabrication WeldAp - Chemical IndustryCd - Creep
Cm - Micrography by OM using A262 Method ADf - Cracks
ML00061 / Apr.2017
Creep in a Seam Weld of a 304H SS Fitting
M - Austenitic Stainless SteelP - Fabrication WeldAp - Chemical IndustryCd - Creep
Cm - Micrography by OM using A262 Method ADf - Base Metal
ML00061 / Apr.2017
Creep in a Seam Weld of a 304H SS Fitting
M - Austenitic Stainless SteelP - Fabrication WeldAp - Chemical IndustryCd - Creep
Cm - Micrography by OM using A262 Method ADf - Base Metal

+10 more from this case →

ML00015 — Intergranular Corrosion of 304SS PlateM - Austenitic Stainless SteelP - Rolled PlateAp - RefineryCd - Intergranular Corrosion
Microstructure of the plate in the center of the ¼” thickness.  Equiaxed austenitic grains with delta ferrite stringers and grain boundary carbide precipitation (sensitization).
303
ML00015 / Oct.2017
Intergranular Corrosion of 304SS Plate
M - Austenitic Stainless SteelP - Rolled PlateAp - RefineryCd - Intergranular Corrosion
Cm - Micrography by OM using A262 Method ADf - Intergranular Precipitation
Microstructure of the plate in the center of the ¼” thickness.  Equiaxed austenitic grains with delta ferrite stringers and grain boundary carbide precipitation (sensitization).
201
ML00015 / Oct.2017
Intergranular Corrosion of 304SS Plate
M - Austenitic Stainless SteelP - Rolled PlateAp - RefineryCd - Intergranular Corrosion
Cm - Micrography by OM using A262 Method ADf - Intergranular Precipitation
Micrographic aspect of a longitudinal section of the plate, close to the surface, in a region where it was detected intergranular corrosion up to 0,5 mm depth.  As polished.
188
ML00015 / Oct.2017
Intergranular Corrosion of 304SS Plate
M - Austenitic Stainless SteelP - Rolled PlateAp - RefineryCd - Intergranular Corrosion
Cm - Micrography by OMDf - Intergranular Corrosion
Micrographic detail of intergranular corrosion, up to 0,5 mm depth.  As polished.
171
ML00015 / Oct.2017
Intergranular Corrosion of 304SS Plate
M - Austenitic Stainless SteelP - Rolled PlateAp - RefineryCd - Intergranular Corrosion
Cm - Micrography by OMDf - Intergranular Corrosion
Micrographic aspect of a longitudinal section of the plate, close to the surface, in a region with intergranular corrosion. Several loose grains were removed, indicating that the structure was embrittled by the intergranular corrosion.
171
ML00015 / Oct.2017
Intergranular Corrosion of 304SS Plate
M - Austenitic Stainless SteelP - Rolled PlateAp - RefineryCd - Intergranular Corrosion
Cm - Micrography by OM using A262 Method ADf - Intergranular Corrosion

+5 more from this case →

ML00038 — Cast SS Tube for High Temperature ServiceM - Heat Resistant SteelP - Centrifugally Cast PipeAp - SiderurgyCd - Creep
ML00038 / Apr.2017
Cast SS Tube for High Temperature Service
M - Heat Resistant SteelP - Centrifugally Cast PipeAp - SiderurgyCd - Creep
Cm - Glyceregia Etched Micrography by OMDf - Close to the External Surface
ML00038 / Apr.2017
Cast SS Tube for High Temperature Service
M - Heat Resistant SteelP - Centrifugally Cast PipeAp - SiderurgyCd - Creep
Cm - Kalling Etched MacroDf - Transverse Section
ML00038 / Apr.2017
Cast SS Tube for High Temperature Service
M - Heat Resistant SteelP - Centrifugally Cast PipeAp - SiderurgyCd - Creep
Cm - Micrography by OMDf - Close to the External Surface
ML00038 / Apr.2017
Cast SS Tube for High Temperature Service
M - Heat Resistant SteelP - Centrifugally Cast PipeAp - SiderurgyCd - Creep
Cm - Micrography by OMDf - Transverse Section
ML00038 / Apr.2017
Cast SS Tube for High Temperature Service
M - Heat Resistant SteelP - Centrifugally Cast PipeAp - SiderurgyCd - Creep
Cm - Glyceregia Etched Micrography by OMDf - Intragranular Secondary Precipitation

+4 more from this case →