Use of conservatism in cathodic protection design
- Det Norske Veritas, Hoevik (Norway)
Sacrificial anode cathodic protection offers cost-effective corrosion protection of submerged marine structures. However, it should be appreciated that longevity of the protection systems can only be estimated with a limited degree of accuracy. To ensure a certain reliability, i.e. probability that a cathodic protection system will achieve its design life, some intentional overcapacity must be included in the design. In contemporary design, specific parameters are defined with an intrinsic conservation rather than using some overall design factor. The paper discusses how design parameters should be selected to provide adequate reliability, taking account of the additional investment cost for an overcapacity which may not be utilized on the one hand, and comparing this with the potential costs associated with increased monitoring and maintenance, including subsea retrofitting of anodes, if the design capacity initially installed proves to be insufficient. A comparison is made between pertinent design parameters in DNV RP B401 (1993), NACE RP0176-94 and NORSOK M-CR-503 (1994).
- OSTI ID:
- 379702
- Report Number(s):
- CONF-960389-; TRN: IM9644%%158
- Resource Relation:
- Conference: National Association of Corrosion Engineers (NACE) annual corrosion conference and exposition: water and waste water industries, Denver, CO (United States), 24-29 Mar 1996; Other Information: PBD: 1996; Related Information: Is Part Of Corrosion/96 conference papers; PB: [6615] p.
- Country of Publication:
- United States
- Language:
- English
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