Page 221 - Handbook Of Multiphase Flow Assurance

220 9. Flow assurance integrity issues

correlations with multiphase flow models such as point or drift flux slip, with varying suc-
cess. The uncertainty in corrosion rate prediction keeps the ILI inspection service companies
in demand. In some instances, best available in-house models for US-based and UK-based
integrated operators underpredicted the corrosion rate in deepwater dense fluid production
and in onshore sour service production. Other companies deploy artificial intelligence to fit
measured rates to corrosion models. Comparison of which flow parameters (calculated with
a commercial multiphase flow simulator) have the most impact showed that holdup and in-
side heat transfer were top (Liao et al., 2012).

Erosion

Besides mechanical degradation of pipe wall surface, erosion by impingement of liquid
droplets or solids such as sand or hydrates affects the integrity of the protective corrosion
inhibitor film or of a corrosion product layer formed on a passivated pipe wall. This may lead
to localized pitting corrosion.

References
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Dillon, C.P. (Ed.), 1982. Forms of Corrosion, Recognition and Prevention. Vol. 7. NACE.
Fischer, D., Li, C., Huang, W., Sun, W., 2016. Investigation of the sulfide stress cracking and stress corrosion cracking
behaviors of duplex and lean duplex stainless steel parent and welded materials in sour service. In: NACE-2016-
7325, Corrosion 2016, 6–10 March, Vancouver.
Fontana, M.G., 1975. The Eight Forms of Corrosion, Process Industries Corrosion. NACE, pp. 1–39.
Hedges, W., Bodington, A., 2004. A comparison of monitoring techniques for improved erosion control: a field study.
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gathering pipelines internal corrosion. Energies 5, 3892–3907.
Wang, S., Nesic, S., 2003. On coupling CO 2 corrosion and multiphase flow models. In: Paper 03631, Corrosion 2003,
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