Welded Joint

3 cases · 64 images

Crevice Corrosion in a Subsea System — Aspect Before Analysis

Image by scanning electron microscopy of the metallurgically bonded interface of the internally cladded pipe.  It is a longitudinal seam welded pipe, with substrate in low alloy steel X65 and clad plate in Alloy 625 (welded by a solid state process). The region is a detail in the side of the Ni alloy clad plate where a grain refinement has occurred probably due to recrystallization of a strain hardened region during later heat treatment. The microhardness of this region is a lot higher than the value obtained out of this region, in the clad plate.
904
ML00133 / May.2018
Seam Welded Pipe Cladded with Alloy 625
M - LAS / Ni AlloyP - Longitudinal Seam Welded PipeAp - Oil and GasCd - Welding
Cm - Oxalic Acid Electrolytic EtchDf - Clad Interface
Micrography of the welded joint, at the root, presenting hot cracks.  The imposed high energy in the root due to the ceramic backing support created a condition for cracking.
1100
ML00118 / Jan.2018
Non qualified GMAW of Aluminum Plates
M - Aluminum Magnesium ManganeseP - Welded Testpiece for QualificationAp - ShipCd - Non qualified
Cm - Keller Etched Micrography by OMDf - Hot cracking
Internal surface detail of the 3 1/2" pipe, cut in a longitudinal section (transverse to the weld), presenting a localized corrosion at the margin of the welded joint (Keller etched), in the root.  The pipeline was assembled with pipes manufactured in two different aluminum alloys, AA 3003 (top of the figure) and AA 6063 (bottom of the figure), and the localized corrosion occurred at the fusion line of the 6063 pipe.
1296
ML00059 / Feb.2018
Intergranular Corrosion of Aluminum Piping
M - Aluminum ManganeseP - Welded JointAp - Chemical IndustryCd - Intergranular Corrosion
Cm - Surface AspectDf - Welded Joint

More from these cases

ML00133 — Seam Welded Pipe Cladded with Alloy 625M - LAS / Ni AlloyP - Longitudinal Seam Welded PipeAp - Oil and GasCd - Welding
ML00133 / May.2018
Seam Welded Pipe Cladded with Alloy 625
M - LAS / Ni AlloyP - Longitudinal Seam Welded PipeAp - Oil and GasCd - Welding
Cm - Aspect Before AnalysisDf - Welded Joint
ML00133 / May.2018
Seam Welded Pipe Cladded with Alloy 625
M - LAS / Ni AlloyP - Longitudinal Seam Welded PipeAp - Oil and GasCd - Welding
Cm - Electrolytically Etched MacroDf - Longitudinal Section
ML00133 / May.2018
Seam Welded Pipe Cladded with Alloy 625
M - LAS / Ni AlloyP - Longitudinal Seam Welded PipeAp - Oil and GasCd - Welding
Cm - Nital Etched Micrography by OMDf - Base Metal
ML00133 / May.2018
Seam Welded Pipe Cladded with Alloy 625
M - LAS / Ni AlloyP - Longitudinal Seam Welded PipeAp - Oil and GasCd - Welding
Cm - Nital Etched Micrography by OMDf - Longitudinal Section
ML00133 / May.2018
Seam Welded Pipe Cladded with Alloy 625
M - LAS / Ni AlloyP - Longitudinal Seam Welded PipeAp - Oil and GasCd - Welding
Cm - Nital Etched Micrography by OMDf - Bainite

+12 more from this case →

ML00118 — Non qualified GMAW of Aluminum PlatesM - Aluminum Magnesium ManganeseP - Welded Testpiece for QualificationAp - ShipCd - Non qualified
Micrography of the welded joint, at the root, showing hot cracks with intergranular morphology.
146
ML00118 / Jan.2018
Non qualified GMAW of Aluminum Plates
M - Aluminum Magnesium ManganeseP - Welded Testpiece for QualificationAp - ShipCd - Non qualified
Cm - Keller Etched Micrography by OMDf - Hot cracking
Micrographic detail of the welded joint, at the root, presenting hot cracks.  The presence of these defects were responsible for reducing the material strenght (rupturing in lower strenght than the requirements) and ductility (cracking in bending tests).
116
ML00118 / Jan.2018
Non qualified GMAW of Aluminum Plates
M - Aluminum Magnesium ManganeseP - Welded Testpiece for QualificationAp - ShipCd - Non qualified
Cm - Keller Etched Micrography by OMDf - Hot cracking
The welded joint of the flat position is shown from the root side.  It is possible to see that the use of the backing generated the possibility for melting the base metal out of the groove, without detection of this condition during welding, responsible for creating defects and avoiding the WPS qualification.
102
ML00118 / Jan.2018
Non qualified GMAW of Aluminum Plates
M - Aluminum Magnesium ManganeseP - Welded Testpiece for QualificationAp - ShipCd - Non qualified
Cm - Aspect Before AnalysisDf - General View
The welded joint of the vertical up position is shown from the root side.  It is possible to see that the use of the backing generated the possibility for melting the base metal out of the groove, without detection of this condition during welding, responsible for creating defects and avoiding the WPS qualification.
122
ML00118 / Jan.2018
Non qualified GMAW of Aluminum Plates
M - Aluminum Magnesium ManganeseP - Welded Testpiece for QualificationAp - ShipCd - Non qualified
Cm - Aspect Before AnalysisDf - General View
Summary of the welding conditions and qualification test results.  NON QUALIFIED WPS. 
The individual parameters for each welding position are presented in the legend of each macrography, that also presents the amount of beads.
117
ML00118 / Jan.2018
Non qualified GMAW of Aluminum Plates
M - Aluminum Magnesium ManganeseP - Welded Testpiece for QualificationAp - ShipCd - Non qualified
Cm - WPS summaryDf - Welded Joint

+22 more from this case →

ML00059 — Intergranular Corrosion of Aluminum PipingM - Aluminum ManganeseP - Welded JointAp - Chemical IndustryCd - Intergranular Corrosion
The macrography of the welded joint shows the AA 6063 alloy pipe in the right and the AA 3003 pipe in the left, welded in two passes.  The root presents small regions of corrosion in the weld metal and a localized corrosion at the fusion line of the 6063 pipe (knife-line attack morphology).
397
ML00059 / Feb.2018
Intergranular Corrosion of Aluminum Piping
M - Aluminum ManganeseP - Welded JointAp - Chemical IndustryCd - Intergranular Corrosion
Cm - Keller Etched MacroDf - Localized Corrosion
Micrography of a longitudinal section of the pipe AA 3003. Granular structure that reveals the forming direction and dispersed particles.
229
ML00059 / Feb.2018
Intergranular Corrosion of Aluminum Piping
M - Aluminum ManganeseP - Welded JointAp - Chemical IndustryCd - Intergranular Corrosion
Cm - Keller Etched Micrography by OMDf - Base Metal Left Side
Micrographic detail of a longitudinal section of the pipe AA 3003. Granular structure and dispersed particles.
199
ML00059 / Feb.2018
Intergranular Corrosion of Aluminum Piping
M - Aluminum ManganeseP - Welded JointAp - Chemical IndustryCd - Intergranular Corrosion
Cm - Keller Etched Micrography by OMDf - Base Metal Left Side
Micrography of a longitudinal section of the pipe AA 6063. Granular structure and dispersed particles.
169
ML00059 / Feb.2018
Intergranular Corrosion of Aluminum Piping
M - Aluminum ManganeseP - Welded JointAp - Chemical IndustryCd - Intergranular Corrosion
Cm - Keller Etched Micrography by OMDf - Base Metal Right Side
Micrographic detail of a longitudinal section of the pipe AA 6063. Granular structure and dispersed particles.
138
ML00059 / Feb.2018
Intergranular Corrosion of Aluminum Piping
M - Aluminum ManganeseP - Welded JointAp - Chemical IndustryCd - Intergranular Corrosion
Cm - Keller Etched MacroDf - Base Metal Right Side

+12 more from this case →