AISI

2 cases · 9 images

Crevice Corrosion in a Subsea System — Aspect Before Analysis

Capture method: Optical Microscope Detail focus: Fatigue Crack clear all

AISI — sub-branches

1010 11020 11045 11070 1304 1304L 1310 1316 5347 Nb stabilized 1409 1410 24130 54140 4420 24330V 14340 24820 16150 28620 18630 1D2 1Dual grade 316/316L 1

Results

SortNewestOldestTitle A-ZTitle Z-A
Macrography of the longitudinal section of the valve body, at the cracked position, a little far from the actuator hole. The valve body is 40 mm thick at this position and it is possible to see that at this position only one region is welded in repair, close to the outer surface (top), and there is a crack, transverse to the thickness, that is difficult to see with this magnification and that is clearly the propagation in fatigue.
47
VIEW
ML00162 / Apr.2020
Valve Body Crack Growth from Weld Defects
M - Low Alloy Medium Carbon QTP - Valve BodyAp - O&G Well DrillingCd - Fatigue Induced by a Defect
Cm - Nital Etched Micrography by OMDf - Fatigue Crack
Micrography of a longitudinal section of the tubular tool, at the external surface close to the fracture position (it is to the top of the figure), showing multiple cracks, slightly branched, fully filled with corrosion products, typical of a corrosion fatigue mechanism. It propagates in a straight front, not affected by banded structures,
53
VIEW
ML00082 / Dec.2017
Corrosion Fatigue of a Drilling Tool
M - Low Alloy Medium Carbon QTP - Tubular ForgingAp - O&G Well DrillingCd - Corrosion Fatigue
Cm - Nital Etched Micrography by OMDf - Fatigue Crack

More from these cases

ML00162 — Valve Body Crack Growth from Weld DefectsM - Low Alloy Medium Carbon QTP - Valve BodyAp - O&G Well DrillingCd - Fatigue Induced by a Defect
Micrography in low magnification, as polished, of the crack in the valve thickness, showing the straight aspect of the fatigue propagation.
24
VIEW
ML00162 / Apr.2020
Valve Body Crack Growth from Weld Defects
M - Low Alloy Medium Carbon QTP - Valve BodyAp - O&G Well DrillingCd - Fatigue Induced by a Defect
Cm - As polished micrographyDf - Fatigue Crack
Micrography, as polished, of the crack in the valve thickness, showing the straight aspect of the fatigue propagation.
22
VIEW
ML00162 / Apr.2020
Valve Body Crack Growth from Weld Defects
M - Low Alloy Medium Carbon QTP - Valve BodyAp - O&G Well DrillingCd - Fatigue Induced by a Defect
Cm - As polished micrographyDf - Fatigue Crack
Micrographic detail of the straight crack that propagated by a fatigue mechanism.
18
VIEW
ML00162 / Apr.2020
Valve Body Crack Growth from Weld Defects
M - Low Alloy Medium Carbon QTP - Valve BodyAp - O&G Well DrillingCd - Fatigue Induced by a Defect
Cm - As polished micrographyDf - Fatigue Crack
Micrography in low magnification of the straight crack in the valve thickness. The crack propagates without following any microstructural aspect. Fatigue is not influenced by microstructure, but by tensile stresses.
23
VIEW
ML00162 / Apr.2020
Valve Body Crack Growth from Weld Defects
M - Low Alloy Medium Carbon QTP - Valve BodyAp - O&G Well DrillingCd - Fatigue Induced by a Defect
Cm - Nital Etched Micrography by OMDf - Fatigue Crack
Micrographic detail of the fatigue cracking, straight and without microstructural influence.
25
VIEW
ML00162 / Apr.2020
Valve Body Crack Growth from Weld Defects
M - Low Alloy Medium Carbon QTP - Valve BodyAp - O&G Well DrillingCd - Fatigue Induced by a Defect
Cm - Nital Etched Micrography by OMDf - Fatigue Crack

+2 more from this case →