Cathodic protection monitoring and survey requirements for offshore platforms and pipelines: Part 3

Abstract

Equipment and typical results from cathodic protection surveying systems. In the simplest form, cathodic protection surveying of fixed offshore platforms is achieved by the so called ‘dipping’ technique, dipping a reference electrode into the sea and measuring a steel/sea potential with respect to it via an indicating voltmeter and a metallic connection to the topside steelwork. This procedure is allowed in NACE RP‐01–76 REF 36 but the standard does address the importance of placing the electrode close to platform members, distant from anodes and into areas of greatest shielding. The conventionally undertaken dip survey, particularly in geographic regions with substantial sea currents which cany the electrode away from structure members, is nothing better than a general indication of the overall level of protection. The probability is of errors indicating better levels than actually exist, due to the IR related voltage drops in the sea between the electrode location and the platform member.

Citation

Wyatt, B.S. (1985), "Cathodic protection monitoring and survey requirements for offshore platforms and pipelines: Part 3", Anti-Corrosion Methods and Materials, Vol. 32 No. 8, pp. 7-11. https://doi.org/10.1108/eb020367