Investigation of cold water pitting corrosion failure of deoxidized high phosphorus (DHP) copper tube: A case study, International Journal of Structural Integrity, Vol. 7 (5) (2016), pp 599-606
Purpose – The purpose of this paper is to identify the corrosion failure mechanism of a Cu
tube in a hydraulic installation and recommend corrective actions to improve the reliability
of the entire unit.
Design/methodology/approach – Failure investigation process includes mainly stereo-, light
optical microscopy and scanning electron microscopy as the main analytical tools for
material characterization and root-cause analysis.
Findings – The investigation findings, obtained by corroded surface analysis and
metallographic evaluation in transverse sections, suggest strongly that the failure was
caused by the operation of Type I pitting corrosion mechanism initiated from the inner side
and propagated towards the outer tube surface, assisted by the flowing medium
Originality/value – This paper deals with an applied failure analysis/case history, summarizes
the stages involved in the mechanism of pitting corrosion Type I, taken place in cold water
systems together with the main parameters and corrosive species that enhance corrosion
rates, shortening pipeline operation life.