Atlas

5 cases · 75 images

Crevice Corrosion in a Subsea System — Aspect Before Analysis

The carcass was manufactured using niobium stabilized plates, grade AISI 347, with circumferential welds, where the through wall cracks were detected.
300
ML00174 / Jul.2021
Carburization of a 347 SS Welded Joint
M - Austenitic Stainless SteelP - Fabrication WeldAp - EnergyCd - Carburization
Cm - Field photoDf - General View
Aspect of a crevice corrosion of the flange, under the bolt head, showing evidences that the cathodic protection system was not connected to the stainless steel instrument.
1434
ML00122 / Feb.2018
Crevice Corrosion in a Subsea System
M - Austenitic Stainless SteelP - CaseAp - Oil and GasCd - Crevice
Cm - Aspect Before AnalysisDf - Localized Corrosion
Draft of the completion riser after removal of the external case showing the hydraulic line position where the 316 tubing is welded by orbital autogenous GTAW to the Nitronic fitting (stab).  In the design of these hydraulic lines, the position of the cracking in the fitting is associated to a slightly bent condition of the fitting due to the misaligment of the tubing axis and the stab axis in the connector, visible in the draft.
1081
ML00095 / Sep.2017
MIC of a Riser Control Line
M - Austenitic Stainless SteelP - Fabrication WeldAp - Oil and GasCd - Brittle Behavior
Cm - Identification drawingDf - General View
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 main pipe, ND 18", has suffered a pipe through wall cracking at the margin of the 1 1/2" branch socket weld.
664
ML00006 / Apr.2017
Vibration Induced Fatigue in 304SS
M - Austenitic Stainless SteelP - Longitudinal Seam Welded PipeAp - PipingCd - Vibration Induced Fatigue
Cm - Aspect Before AnalysisDf - Crack

More from these cases

ML00174 — Carburization of a 347 SS Welded JointM - Austenitic Stainless SteelP - Fabrication WeldAp - EnergyCd - Carburization
ML00174 / Jul.2021
Carburization of a 347 SS Welded Joint
M - Austenitic Stainless SteelP - Fabrication WeldAp - EnergyCd - Carburization
Cm - Aspect by NDTDf - Multiple cracks
ML00174 / Jul.2021
Carburization of a 347 SS Welded Joint
M - Austenitic Stainless SteelP - Fabrication WeldAp - EnergyCd - Carburization
Cm - Aspect Before AnalysisDf - At the Surface
ML00174 / Jul.2021
Carburization of a 347 SS Welded Joint
M - Austenitic Stainless SteelP - Fabrication WeldAp - EnergyCd - Carburization
Cm - Testpiece aspectDf - Fracture
ML00174 / Jul.2021
Carburization of a 347 SS Welded Joint
M - Austenitic Stainless SteelP - Fabrication WeldAp - EnergyCd - Carburization
Cm - Aspect Before AnalysisDf - Fracture
ML00174 / Jul.2021
Carburization of a 347 SS Welded Joint
M - Austenitic Stainless SteelP - Fabrication WeldAp - EnergyCd - Carburization
Cm - Fractography by SEMDf - Brittle Fracture

+10 more from this case →

ML00122 — Crevice Corrosion in a Subsea SystemM - Austenitic Stainless SteelP - CaseAp - Oil and GasCd - Crevice
Flanged case, 640mm long.  The photo presents a general view of the instrumentation system, destroyed after only 6 months in subsea service.  The system was manufactured using only 316 stainless steel and the case was 20 mm thick.
335
ML00122 / Feb.2018
Crevice Corrosion in a Subsea System
M - Austenitic Stainless SteelP - CaseAp - Oil and GasCd - Crevice
Cm - Aspect Before AnalysisDf - General View
Aspect of the instrument system after disassembling.  The internal part of the case, where the electronic device was operating, was wet by seawater and failed to send signals to the surface.
258
ML00122 / Feb.2018
Crevice Corrosion in a Subsea System
M - Austenitic Stainless SteelP - CaseAp - Oil and GasCd - Crevice
Cm - Aspect Before AnalysisDf - General View
Detail of the electronic device after removing the external case.  It is corroded because seawater entered in the equipment that was pressurized from the external sea environment.
228
ML00122 / Feb.2018
Crevice Corrosion in a Subsea System
M - Austenitic Stainless SteelP - CaseAp - Oil and GasCd - Crevice
Cm - Aspect Before AnalysisDf - Corrosion
After a longitudinal cut of the case it was possible to see that a localized corrosion has occurred associated to the regions where there were sealed holes, plugged, in a crevice condition, not related to any welded position.
193
ML00122 / Feb.2018
Crevice Corrosion in a Subsea System
M - Austenitic Stainless SteelP - CaseAp - Oil and GasCd - Crevice
Cm - Transverse Section AspectDf - Corrosion
Micrography of the case, observed in the center of the thickness, showing an equiaxial granular austenitic microstructure, free from carbides.  The structure is typical of a 316 SS, in a solution annealed condition.
176
ML00122 / Feb.2018
Crevice Corrosion in a Subsea System
M - Austenitic Stainless SteelP - CaseAp - Oil and GasCd - Crevice
Cm - Micrography by OM using A262 Method ADf - Austenite

+11 more from this case →

ML00095 — MIC of a Riser Control LineM - Austenitic Stainless SteelP - Fabrication WeldAp - Oil and GasCd - Brittle Behavior
Aspect of the hydraulic line samples removed from service to be analyzed.  Tubing and welded joint (bottom sample) between the 316 tubing (left side of the sample) and the nitronic fitting (right side of the sample).   The cracking is located 10 mm far from the weld, autogenous orbital GTAW.
108
ML00095 / Sep.2017
MIC of a Riser Control Line
M - Austenitic Stainless SteelP - Fabrication WeldAp - Oil and GasCd - Brittle Behavior
Cm - Aspect Before AnalysisDf - General View
ML00095 / Sep.2017
MIC of a Riser Control Line
M - Austenitic Stainless SteelP - Fabrication WeldAp - Oil and GasCd - Brittle Behavior
Cm - Surface Aspect by SEMDf - External Surface
ML00095 / Sep.2017
MIC of a Riser Control Line
M - Austenitic Stainless SteelP - Fabrication WeldAp - Oil and GasCd - Brittle Behavior
Cm - Surface Aspect by SEMDf - Branched Cracks
ML00095 / Sep.2017
MIC of a Riser Control Line
M - Austenitic Stainless SteelP - Fabrication WeldAp - Oil and GasCd - Brittle Behavior
Cm - Aspect Before AnalysisDf - Welded Joint
ML00095 / Sep.2017
MIC of a Riser Control Line
M - Austenitic Stainless SteelP - Fabrication WeldAp - Oil and GasCd - Brittle Behavior
Cm - Macro Oxalic Acid Electrolytic EtchedDf - Longitudinal Section

+10 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 →

ML00006 — Vibration Induced Fatigue in 304SSM - Austenitic Stainless SteelP - Longitudinal Seam Welded PipeAp - PipingCd - Vibration Induced Fatigue
The macro section transverse to the welded region, show that the through wall cracking occurred in the pipe base metal, from the margin of the weld.
191
ML00006 / Apr.2017
Vibration Induced Fatigue in 304SS
M - Austenitic Stainless SteelP - Longitudinal Seam Welded PipeAp - PipingCd - Vibration Induced Fatigue
Cm - Macro Oxalic Acid Electrolytic EtchedDf - Through Wall Cracking
Macro transverse to the weld showing that the fracture occurred in the main pipe, at the margin of the weld.
163
ML00006 / Apr.2017
Vibration Induced Fatigue in 304SS
M - Austenitic Stainless SteelP - Longitudinal Seam Welded PipeAp - PipingCd - Vibration Induced Fatigue
Cm - Macro Oxalic Acid Electrolytic EtchedDf - Fracture
The fracture surface of the main pipe is presented in low magnification (external pipe surface in the top) showing a flat propagation starting from the contour of the weld margin.
173
ML00006 / Apr.2017
Vibration Induced Fatigue in 304SS
M - Austenitic Stainless SteelP - Longitudinal Seam Welded PipeAp - PipingCd - Vibration Induced Fatigue
Cm - Fractography by SEMDf - Margin of the Weld Crack
Fracture surface micromechanism by striation, evidence of FATIGUE.
158
ML00006 / Apr.2017
Vibration Induced Fatigue in 304SS
M - Austenitic Stainless SteelP - Longitudinal Seam Welded PipeAp - PipingCd - Vibration Induced Fatigue
Cm - Fractography by SEMDf - Fatigue Striation
Fracture surface micromechanism by striation, evidence of FATIGUE.
147
ML00006 / Apr.2017
Vibration Induced Fatigue in 304SS
M - Austenitic Stainless SteelP - Longitudinal Seam Welded PipeAp - PipingCd - Vibration Induced Fatigue
Cm - Fractography by SEMDf - Fatigue Striation

+4 more from this case →