Evaluation of the effects of seawater ingress into 316L lined pipes on corrosion performance

Abstract

The potential effects of seawater ingress into 316L lined pipes during subsea tie-in operations on corrosion performance were investigated. Immersion and accelerated corrosion tests were conducted on 316L in different mixtures of treated seawater. In particular, we examined the effect of oxygen and microorganisms in seawater on the performance of the alloy at the different mixtures of treated seawater to assess the risk of localized corrosion in the event of seawater ingress into pipelines. Results showed that oxygen has a negative impact on the biocidal and oxygen scavenging efficiency of the chemical treatments and a detrimental effect on pitting corrosion.

X‐ray micro‐computed tomography analysis of accumulated corrosion products in deep‐water shipwrecks

“…Figure a shows the presence of assemblages of corrosion products as bacillary forms. These morphologies have been previously observed in the rusticles from other shipwrecks and have been associated with the prolonged activity of metal‐precipitating bacteria, which ultimately leads to the entombment of the cells within the corrosion products. Extensive voids (cavities) were also observed on the surface in Figure a and similar observations were reported in the literature of rusticles formation on shipwrecks .…”

Filtration–UV irradiation as an option for mitigating the risk of microbiologically influenced corrosion of subsea construction alloys in seawater

“…The use of natural seawater in the hydrotesting of subsea pipelines prior to commissioning is becoming an issue of increasing importance to the oil and gas industry. This practice can contaminate the internal surface with microorganisms, sand and salts, even after the water has been removed, increasing the possibility of internal localized corrosion, particularly MIC [28][29][30]. Therefore, hydrotest seawater must be properly treated in order to reduce the possibility of contamination and severe corrosion damage and to prolong pipeline and equipment service life [31,32].…”

The influence of sulphate‐reducing bacteria on heterogeneous electrochemical corrosion behavior of Q235 carbon steel in seawater

“…In marine environments, sulphate-reducing bacteria (SRB) are regarded as the main culprits that affect electrochemical corrosion behavior of metal in anaerobic condition [1][2][3][4]. As one kind of typical localized corrosion, SRB induced corrosion has been investigated extensively, and many mechanisms were proposed [5][6][7][8][9].…”