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Stresses are introduced into the tube by the rolling operation. If these rolled connections leak-by, caustic from the boiler treatment concentrates in the crevice and leads to failure. Similar failures can occur on any tube with a leaking rolled connection.
Issue Type:Near or in weld or attachment
Locations:Riser tube at rolled connection in drum
Mechanism:Caustic Induced Stress Corrosion Cracking
Download a PDFTransverse cracking in the rolled portion of tube where it is inserted into the drum