Back to Austenitic Stainless Steel
ML00050 - Nov.2017

Fatigue Failure of a 316SS Pressure Stabilizer

The micrography of the welded joint between the flange and the shell, in a region that was not yet macroscopically cracked, presented a fatigue crack from the margin of the fillet weld.

9

72
The of the between the and the shell, in a region that was not yet macroscopically cracked, presented a from the margin of the .
M

Material

Austenitic Stainless Steel
  • UNS S31603
  • ASTM A 240 TP 316L
Ds

Description

The equipment has failed by after a very short time in operation, less than one month. The iniciated at the margin of the connecting the to the shell, and propagated through the shell wall thickness. The analysis showed striation as the . No manufacturing problems were identified.

C

Chemistry (% in weight)

Shell Plate Product Analysis

0.03C; 0.55Si; 1.80Mn; 0.023P; 0.005S; 16.5Cr; 10.5Ni; 2.1Mo.

Associated Images
Micrographic detail of the fatigue cracking at the margin of the flange to shell fillet weld.
485
VIEW
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 equipment presenting a through wall cracking at the margin of the fillet weld.
143
VIEW
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°.
117
VIEW
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
VIEW
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
The macrography of a transverse section of the shell to flange weld (Lepto's etch) shows that the cracking occurred through the shell plate thickness, at the margin of the fillet weld.
93
VIEW
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
VIEW
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
Schematic drawing presenting the position of the crack at the margin of the weld, through thickness of the shell plate.
75
VIEW
ML00050 / Nov.2017
Fatigue Failure of a 316SS Pressure Stabilizer
M - Austenitic Stainless SteelP - Fabrication WeldAp - Chemical IndustryCd - Mechanical Fatigue
Cm - Identification drawingDf - At the Surface
The micrography of the welded joint between the flange and the shell, in a region that was through wall cracked, the fracture propagating in the shell plate base metal.
74
VIEW
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 - Welded Joint
The micrography of the welded joint between the flange and the shell, in a region that was not yet macroscopically cracked, presented a fatigue crack from the margin of the fillet weld.
72
VIEW
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 - Welded Joint