479

2 cases · 28 images

Crevice Corrosion in a Subsea System — Aspect Before Analysis

479 — sub-branches

Aspect of the male part of the coupling, a pin, presenting the thermal spray layer detachment (right side of the figure). The pin was manufactured in a superduplex stainless steel tubular forging; the external surface was partially coated by thermal spray and machined.  The sealing is only elastomeric but a coating is required to avoid galling between the two materials of the coupling.
1154
ML00146 / Jul.2018
Plastic Deformation of a SDSS Riser Pin
M - Super Duplex Stainless SteelP - PinAp - O&G Well DrillingCd - Bending
Cm - Aspect Before AnalysisDf - Layer Detachment
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

More from these cases

ML00146 — Plastic Deformation of a SDSS Riser PinM - Super Duplex Stainless SteelP - PinAp - O&G Well DrillingCd - Bending
The longitudinal section of the pin shows that it was deformed in a localized position, where the layer was detached, top side of the figure. The pin wall was plastically deformed decreasing the internal diameter.
222
ML00146 / Jul.2018
Plastic Deformation of a SDSS Riser Pin
M - Super Duplex Stainless SteelP - PinAp - O&G Well DrillingCd - Bending
Cm - Longitudinal Section AspectDf - Plastic Deformation
Micrography of the longitudinal section, in the center of the thickness of the pin, presenting an aligned ferritic-austeinitic structure.
180
ML00146 / Jul.2018
Plastic Deformation of a SDSS Riser Pin
M - Super Duplex Stainless SteelP - PinAp - O&G Well DrillingCd - Bending
Cm - NaOH Electrolytic Etched MicroDf - Ferrite and Austenite
Micrography of a longitudinal section, at the surface of the pin, where the thermal spray layer is sound. The thickness of the layer is about 0.3 mm.
168
ML00146 / Jul.2018
Plastic Deformation of a SDSS Riser Pin
M - Super Duplex Stainless SteelP - PinAp - O&G Well DrillingCd - Bending
Cm - NaOH Electrolytic Etched MicroDf - Coating Layer
Micrographic detail of a longitudinal section of the pin, at the surface, evidencing the thermal spray layer, about 0.3 mm.  The layer presents typical characteristics of multiple layers, low amount of entrapped oxides and pores.  The interface presents a high roughness level for a good adherence and some entrapped oxides. The structure of the SDSS substrate did not show thermal effects.
154
ML00146 / Jul.2018
Plastic Deformation of a SDSS Riser Pin
M - Super Duplex Stainless SteelP - PinAp - O&G Well DrillingCd - Bending
Cm - NaOH Electrolytic Etched MicroDf - Coating Layer
The longitudinal section of the pin at the region of the thermal spray layer detachment, showing that the pin suffered a localized lateral bending with strong plastic deformation, responsible for the layer detachment.  The figure shows the external surface (top of the figure) with the layer detachment (gray aspect), the thickness of the pin (deformed) and the internal surface (bright aspect).
124
ML00146 / Jul.2018
Plastic Deformation of a SDSS Riser Pin
M - Super Duplex Stainless SteelP - PinAp - O&G Well DrillingCd - Bending
Cm - Longitudinal Section AspectDf - Plastic Deformation

+2 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 →