Stress corrosion cracking of a copper elbow fitting. (August 2018)

• Record Type: Journal Article
• Authors: Metcalfe, R.G.; Pearce-Boltec, N.
• Is Part Of: Engineering failure analysis. Volume 90(2018)
• Page Start: 197
• Page End: 201
• Publication Date: 2018-08
• Subjects: Amines -- DHP copper -- Elbow fitting -- Intergranular SCC -- Liquid nitrogen pipeline -- Polyurethane insulation; System failures (Engineering) -- Periodicals; Fracture mechanics -- Periodicals; Reliability (Engineering) -- Periodicals; Pannes -- Périodiques; Rupture, Mécanique de la -- Périodiques; Fiabilité -- Périodiques; Fracture mechanics; Reliability (Engineering); System failures (Engineering); Periodicals; Electronic journals; 620.112
• DOI: 10.1016/j.engfailanal.2018.03.016
• Languages: English
• ISSNs: 1350-6307

Abstract

Abstract: This paper presents the results of an examination of cracking in a phosphorous deoxidised copper fitting that had been installed in a liquid nitrogen line. The service life of the fitting was reported to be three to four years. Failure was a result of the Stress Corrosion Cracking (SCC) from the outside surface that had been placed in tension by the pipeline being chocked with a block of wood to locally raise the line above a cable tray. The active species for SCC was suspected of being Amines in the Polyurethane insulation. Highlights: The room temperature Intergranular SCC of a high purity copper fitting is described. The active species is proposed to be amines associated with the polyurethane foam insulation. Stresses present associated with installation